1# @ohos.display (Display) 2 3The Display module provides APIs for managing displays, such as obtaining information about the default display, obtaining information about all displays, and listening for the addition and removal of displays. 4 5> **NOTE** 6> 7> The initial APIs of this module are supported since API version 7. Newly added APIs will be marked with a superscript to indicate their earliest API version. 8 9## Modules to Import 10 11```ts 12import { display } from '@kit.ArkUI'; 13``` 14 15## DisplayState 16 17Enumerates the states of a display. 18 19**Atomic service API**: This API can be used in atomic services since API version 12. 20 21**System capability**: SystemCapability.WindowManager.WindowManager.Core 22 23| Name| Value| Description| 24| -------- | -------- | -------- | 25| STATE_UNKNOWN | 0 | Unknown.| 26| STATE_OFF | 1 | The display is shut down.| 27| STATE_ON | 2 | The display is powered on.| 28| STATE_DOZE | 3 | The display is in sleep mode.| 29| STATE_DOZE_SUSPEND | 4 | The display is in sleep mode, and the CPU is suspended.| 30| STATE_VR | 5 | The display is in VR mode.| 31| STATE_ON_SUSPEND | 6 | The display is powered on, and the CPU is suspended.| 32 33## Orientation<sup>10+</sup> 34 35Enumerates the orientations of a display. 36 37**Atomic service API**: This API can be used in atomic services since API version 12. 38 39**System capability**: SystemCapability.WindowManager.WindowManager.Core 40 41| Name| Value| Description| 42| -------- | -------- | -------- | 43| PORTRAIT | 0 | The display is in portrait mode.| 44| LANDSCAPE | 1 | The display is in landscape mode.| 45| PORTRAIT_INVERTED | 2 | The display is in reverse portrait mode.| 46| LANDSCAPE_INVERTED | 3 | The display is in reverse landscape mode.| 47 48## FoldStatus<sup>10+</sup> 49 50Enumerates the fold statuses of a foldable device. 51 52**Atomic service API**: This API can be used in atomic services since API version 12. 53 54**System capability**: SystemCapability.Window.SessionManager 55 56| Name| Value| Description| 57| -------- | -------- | -------- | 58| FOLD_STATUS_UNKNOWN | 0 | The fold status of the device is unknown.| 59| FOLD_STATUS_EXPANDED | 1 | The device is fully open. | 60| FOLD_STATUS_FOLDED | 2 | The device is folded (completely closed). | 61| FOLD_STATUS_HALF_FOLDED | 3 | The device is half-folded, somehow between fully open and completely closed. | 62 63## FoldDisplayMode<sup>10+</sup> 64 65Enumerates the display modes of a foldable device. 66 67**Atomic service API**: This API can be used in atomic services since API version 12. 68 69**System capability**: SystemCapability.Window.SessionManager 70 71| Name| Value| Description| 72| -------- | -------- | -------- | 73| FOLD_DISPLAY_MODE_UNKNOWN | 0 | The display mode of the device is unknown.| 74| FOLD_DISPLAY_MODE_FULL | 1 | The device is displayed in full screen.| 75| FOLD_DISPLAY_MODE_MAIN | 2 | The main screen of the device is displayed.| 76| FOLD_DISPLAY_MODE_SUB | 3 | The subscreen of the device is displayed.| 77| FOLD_DISPLAY_MODE_COORDINATION | 4 | Both screens of the device are displayed in collaborative mode.| 78 79>**NOTE**<br> 80>• For large-screen inward-foldable devices, the inner screen is the **FOLD_DISPLAY_MODE_FULL** state, and the outer screen is in the **FOLD_DISPLAY_MODE_MAIN** state.<br> 81>• For small-screen inward-foldable devices, the inner screen is the **FOLD_DISPLAY_MODE_MAIN** state, and the outer screen is in the **FOLD_DISPLAY_MODE_SUB** state. 82 83## FoldCreaseRegion<sup>10+</sup> 84 85Defines the crease region of a foldable device. 86 87**Atomic service API**: This API can be used in atomic services since API version 12. 88 89**System capability**: SystemCapability.Window.SessionManager 90 91| Name | Type| Readable| Writable| Description | 92| ------ | -------- | ---- | ---- | ------------------ | 93| displayId | number | Yes | No | ID of the display where the crease is located.| 94| creaseRects | Array\<[Rect](#rect9)> | Yes | No | Crease region.| 95 96## Rect<sup>9+</sup> 97 98Describes a rectangle on the display. 99 100**Atomic service API**: This API can be used in atomic services since API version 12. 101 102**System capability**: SystemCapability.WindowManager.WindowManager.Core 103 104| Name | Type| Readable| Writable| Description | 105| ------ | -------- | ---- | ---- | ------------------ | 106| left | number | Yes | Yes | Left boundary of the rectangle, in px. The value must be an integer.| 107| top | number | Yes | Yes | Top boundary of the rectangle, in px. The value must be an integer.| 108| width | number | Yes | Yes | Width of the rectangle, in px. The value must be an integer. | 109| height | number | Yes | Yes | Height of the rectangle, in px. The value must be an integer. | 110 111## WaterfallDisplayAreaRects<sup>9+</sup> 112 113Describes the curved area on a waterfall display. 114 115**Atomic service API**: This API can be used in atomic services since API version 12. 116 117**System capability**: SystemCapability.WindowManager.WindowManager.Core 118 119| Name | Type | Readable| Writable| Description | 120| ------ | ------------- | ---- | ---- | ------------------ | 121| left | [Rect](#rect9) | Yes | No | Rectangle of the curved area on the left of the waterfall display.| 122| top | [Rect](#rect9) | Yes | No | Rectangle of the curved area on the top of the waterfall display.| 123| right | [Rect](#rect9) | Yes | No | Rectangle of the curved area on the right of the waterfall display.| 124| bottom | [Rect](#rect9) | Yes | No | Rectangle of the curved area at the bottom of the waterfall display.| 125 126## CutoutInfo<sup>9+</sup> 127 128Describes the unusable area of a display, including punch hole, notch, and curved area of a waterfall display. 129 130**Atomic service API**: This API can be used in atomic services since API version 12. 131 132**System capability**: SystemCapability.WindowManager.WindowManager.Core 133 134| Name | Type | Readable| Writable| Description | 135| --------------------------- | ------------- | ---- | ---- | ------------------ | 136| boundingRects | Array\<[Rect](#rect9)> | Yes | No | Unusable areas (bounding rectangles) designed for punch holes and notches.| 137| waterfallDisplayAreaRects | [WaterfallDisplayAreaRects](#waterfalldisplayarearects9) | Yes| No| Curved area on a waterfall display.| 138 139## DisplayPhysicalResolution<sup>12+</sup> 140Describes the display mode of a foldable device and the corresponding physical screen resolution information. 141 142**Atomic service API**: This API can be used in atomic services since API version 12. 143 144**System capability**: SystemCapability.WindowManager.WindowManager.Core 145 146| Name | Type | Read-Only| Optional| Description | 147| --------------------------- | ------------- | ---- | ---- | ------------------ | 148| foldDisplayMode | [FoldDisplayMode](#folddisplaymode10) | Yes | No | Display mode of the foldable device.| 149| physicalWidth | number | Yes| No| Width of the foldable device, in px. The value must be an integer greater than 0.| 150| physicalHeight | number | Yes| No| Height of the foldable device, in px. The value must be an integer greater than 0.| 151 152## display.getDisplayByIdSync<sup>12+</sup> 153 154getDisplayByIdSync(displayId: number): Display 155 156Obtains a **Display** object based on the display ID. 157 158**System capability**: SystemCapability.WindowManager.WindowManager.Core 159 160**Atomic service API**: This API can be used in atomic services since API version 12. 161 162**Parameters** 163 164| Name| Type | Mandatory| Description | 165| ------ | ------------------------- | ---- |----------| 166| displayId | number | Yes | Display ID. The value must be an integer greater than or equal to 0. An object can be obtained only when the passed-in display ID is correct. You can use the value of the **displayId** property in [WindowProperties](js-apis-window.md#windowproperties) as the input parameter.| 167 168**Return value** 169 170| Type | Description | 171| ------------------------------| ----------------------------------------------| 172| [Display](#display) | **Display** object.| 173 174**Error codes** 175 176For details about the error codes, see [Universal Error Codes](../errorcode-universal.md) and [Display Error Codes](errorcode-display.md). 177 178| ID| Error Message| 179| ------- | ----------------------- | 180| 401 | Parameter error. Possible causes: 1. Mandatory parameters are left unspecified.2. Incorrect parameter types. 3. Parameter verification failed.| 181| 1400003 | This display manager service works abnormally. | 182 183**Example** 184 185```ts 186import { display } from '@kit.ArkUI'; 187 188let displayClass: display.Display | null = null; 189 190try { 191 // Use the value of the displayId property in WindowProperties as the input parameter. 192 let displayId = 0; 193 displayClass = display.getDisplayByIdSync(displayId); 194} catch (exception) { 195 console.error(`Failed to get display. Code: ${exception.code}, message: ${exception.message}`); 196} 197``` 198 199## display.getAllDisplayPhysicalResolution<sup>12+</sup> 200 201getAllDisplayPhysicalResolution(): Promise<Array<DisplayPhysicalResolution>> 202 203Obtains the display mode of the current foldable device and the corresponding physical screen resolution information. 204 205**Atomic service API**: This API can be used in atomic services since API version 12. 206 207**System capability**: SystemCapability.WindowManager.WindowManager.Core 208 209**Return value** 210 211| Type| Description| 212| ----------------------------------------------- | ------------------------------------------------------- | 213| Promise<Array<[DisplayPhysicalResolution](#displayphysicalresolution12)>> | Promise used to return all the **DisplayPhysicalResolution** objects.| 214 215**Error codes** 216 217For details about the error codes, see [Display Error Codes](errorcode-display.md). 218 219| ID| Error Message| 220| ------- | ----------------------- | 221| 1400003 | This display manager service works abnormally. | 222 223**Example** 224 225```ts 226import { BusinessError } from '@kit.BasicServicesKit'; 227import { display } from '@kit.ArkUI'; 228 229let promise = display.getAllDisplayPhysicalResolution(); 230promise.then((resolutionObjects) => { 231 console.info('Obtaining physical resolution length: ' + resolutionObjects.length); 232 for (let i = 0; i < resolutionObjects.length; i++) { 233 console.info(`resolutionObjects[${i}].foldDisplayMode: ${resolutionObjects[i].foldDisplayMode}`); 234 console.info(`resolutionObjects[${i}].physicalWidth: ${resolutionObjects[i].physicalWidth}`); 235 console.info(`resolutionObjects[${i}].physicalHeight: ${resolutionObjects[i].physicalHeight}`); 236 } 237}).catch((err: BusinessError) => { 238 console.error(`Failed to obtain physical resolution. Code: ${err.code}, message: ${err.message}`); 239}); 240``` 241 242## display.getDefaultDisplaySync<sup>9+</sup> 243 244getDefaultDisplaySync(): Display 245 246Obtains the default display object. This API returns the result synchronously. 247 248**System capability**: SystemCapability.WindowManager.WindowManager.Core 249 250**Atomic service API**: This API can be used in atomic services since API version 11. 251 252**Return value** 253 254| Type | Description | 255| ------------------------------| ----------------------------------------------| 256| [Display](#display) | Default display object.| 257 258**Error codes** 259 260For details about the error codes, see [Display Error Codes](errorcode-display.md). 261 262| ID| Error Message| 263| ------- | ----------------------- | 264| 1400001 | Invalid display or screen. | 265 266**Example** 267 268```ts 269import { display } from '@kit.ArkUI'; 270 271let displayClass: display.Display | null = null; 272 273displayClass = display.getDefaultDisplaySync(); 274``` 275 276## display.getPrimaryDisplaySync<sup>14+</sup> 277 278getPrimaryDisplaySync(): Display 279 280Obtains the information about the primary display. For devices other than 2-in-1 devices, the **Display** object obtained is the built-in screen. For 2-in-1 devices with an external screen, the **Display** object obtained is the primary screen. For 2-in-1 devices without an external screen, the Display object obtained is the built-in screen. 281 282**System capability**: SystemCapability.WindowManager.WindowManager.Core 283 284**Atomic service API**: This API can be used in atomic services since API version 14. 285 286**Return value** 287 288| Type | Description | 289| ------------------------------| ----------------------------------------------| 290| [Display](#display) | **Display** object of the primary screen.| 291 292**Error codes** 293 294For details about the error codes, see [Display Error Codes](errorcode-display.md). 295 296| ID| Error Message| 297| ------- | ----------------------- | 298| 1400001 | Invalid display or screen. | 299 300**Example** 301 302```ts 303import { display } from '@kit.ArkUI'; 304 305let displayClass: display.Display | null = null; 306 307displayClass = display.getPrimaryDisplaySync(); 308``` 309 310## display.getAllDisplays<sup>9+</sup> 311 312getAllDisplays(callback: AsyncCallback<Array<Display>>): void 313 314Obtains all display objects. This API uses an asynchronous callback to return the result. 315 316**Atomic service API**: This API can be used in atomic services since API version 12. 317 318**System capability**: SystemCapability.WindowManager.WindowManager.Core 319 320**Parameters** 321 322| Name| Type| Mandatory| Description| 323| -------- | ---------------------------------------------------- | ---- | ------------------------------- | 324| callback | AsyncCallback<Array<[Display](#display)>> | Yes| Callback used to return all the display objects.| 325 326**Error codes** 327 328For details about the error codes, see [Display Error Codes](errorcode-display.md). 329 330| ID| Error Message| 331| ------- | ----------------------- | 332| 1400001 | Invalid display or screen. | 333 334**Example** 335 336```ts 337import { BusinessError } from '@kit.BasicServicesKit'; 338import { display } from '@kit.ArkUI'; 339 340let displayClass: Array<display.Display> = []; 341display.getAllDisplays((err: BusinessError, data: Array<display.Display>) => { 342 displayClass = data; 343 const errCode: number = err.code; 344 if (errCode) { 345 console.error(`Failed to obtain all the display objects. Code: ${err.code}, message: ${err.message}`); 346 return; 347 } 348 console.info('Succeeded in obtaining all the display objects. Data: ' + JSON.stringify(data)); 349}); 350``` 351 352## display.getAllDisplays<sup>9+</sup> 353 354getAllDisplays(): Promise<Array<Display>> 355 356Obtains all display objects. This API uses a promise to return the result. 357 358**Atomic service API**: This API can be used in atomic services since API version 12. 359 360**System capability**: SystemCapability.WindowManager.WindowManager.Core 361 362**Return value** 363 364| Type| Description| 365| ----------------------------------------------- | ------------------------------------------------------- | 366| Promise<Array<[Display](#display)>> | Promise used to return all the display objects.| 367 368**Error codes** 369 370For details about the error codes, see [Display Error Codes](errorcode-display.md). 371 372| ID| Error Message| 373| ------- | ----------------------- | 374| 1400001 | Invalid display or screen. | 375 376**Example** 377 378```ts 379import { BusinessError } from '@kit.BasicServicesKit'; 380import { display } from '@kit.ArkUI'; 381 382let displayClass: Array<display.Display> =[]; 383let promise: Promise<Array<display.Display>> = display.getAllDisplays(); 384promise.then((data: Array<display.Display>) => { 385 displayClass = data; 386 console.info('Succeeded in obtaining all the display objects. Data: ' + JSON.stringify(data)); 387}).catch((err: BusinessError) => { 388 console.error(`Failed to obtain all the display objects. Code: ${err.code}, message: ${err.message}`); 389}); 390``` 391 392## display.on('add'|'remove'|'change') 393 394on(type: 'add'|'remove'|'change', callback: Callback<number>): void 395 396Subscribes to display changes. 397 398**Atomic service API**: This API can be used in atomic services since API version 12. 399 400**System capability**: SystemCapability.WindowManager.WindowManager.Core 401 402**Parameters** 403 404| Name| Type| Mandatory| Description | 405| -------- | -------- | -------- |---------------------------------------------------------------------------------------------------------------------------------| 406| type | string | Yes| Event type.<br>- **add**, indicating the display addition event. Example: event that a display is connected.<br>- **remove**, indicating the display removal event. Example: event that a display is disconnected.<br>- **change**, indicating the display change event. Example: event that the display orientation is changed.| 407| callback | Callback<number> | Yes| Callback used to return the ID of the display, which is an integer. | 408 409**Error codes** 410 411For details about the error codes, see [Universal Error Codes](../errorcode-universal.md). 412 413| ID| Error Message| 414| ------- | ----------------------- | 415| 401 | Parameter error. Possible causes: 1.Mandatory parameters are left unspecified. 2.Incorrect parameter types.| 416 417**Example** 418 419```ts 420import { Callback } from '@kit.BasicServicesKit'; 421 422let callback: Callback<number> = (data: number) => { 423 console.info('Listening enabled. Data: ' + JSON.stringify(data)); 424}; 425 426display.on("add", callback); 427``` 428 429## display.off('add'|'remove'|'change') 430 431off(type: 'add'|'remove'|'change', callback?: Callback<number>): void 432 433Unsubscribes from display changes. 434 435**Atomic service API**: This API can be used in atomic services since API version 12. 436 437**System capability**: SystemCapability.WindowManager.WindowManager.Core 438 439**Parameters** 440 441| Name| Type| Mandatory| Description| 442| -------- | -------- | -------- | -------- | 443| type | string | Yes| Event type.<br>- **add**, indicating the display addition event. Example: event that a display is connected.<br>- **remove**, indicating the display removal event. Example: event that a display is disconnected.<br>- **change**, indicating the display change event. Example: event that the display orientation is changed.| 444| callback | Callback<number> | No| Callback used for unsubscription. If this parameter is not specified, all callbacks of the specified type will be unregistered.| 445 446**Error codes** 447 448For details about the error codes, see [Universal Error Codes](../errorcode-universal.md). 449 450| ID| Error Message| 451| ------- | ----------------------- | 452| 401 | Parameter error. Possible causes: 1.Mandatory parameters are left unspecified. 2.Incorrect parameter types.| 453 454**Example** 455 456```ts 457 458// Unregister all the callbacks that have been registered through on(). 459display.off("remove"); 460 461let callback: Callback<number> = (data: number) => { 462 console.info('Succeeded in unregistering the callback for display remove. Data: ' + JSON.stringify(data)) 463}; 464// Unregister the specified callback. 465display.off('remove', callback); 466``` 467 468## display.isFoldable<sup>10+</sup> 469isFoldable(): boolean 470 471Checks whether the current device is foldable. 472 473**Atomic service API**: This API can be used in atomic services since API version 12. 474 475**System capability**: SystemCapability.Window.SessionManager 476 477**Return value** 478 479| Type| Description| 480| ----------------------------------------------- | ------------------------------------------------------- | 481| boolean | Returns **true** if the device is foldable, and returns **false** otherwise.| 482 483**Error codes** 484 485For details about the error codes, see [Display Error Codes](errorcode-display.md). 486 487| ID| Error Message| 488| ------- | ----------------------- | 489| 1400003 | This display manager service works abnormally. | 490 491**Example** 492 493```ts 494import { display } from '@kit.ArkUI'; 495 496let ret: boolean = false; 497ret = display.isFoldable(); 498``` 499 500## display.getFoldStatus<sup>10+</sup> 501getFoldStatus(): FoldStatus 502 503Obtains the fold status of the foldable device. 504 505**Atomic service API**: This API can be used in atomic services since API version 12. 506 507**System capability**: SystemCapability.Window.SessionManager 508 509**Return value** 510 511| Type| Description| 512| ----------------------------------------------- | ------------------------------------------------------- | 513| [FoldStatus](#foldstatus10) | Fold status of the device.| 514 515**Error codes** 516 517For details about the error codes, see [Display Error Codes](errorcode-display.md). 518 519| ID| Error Message| 520| ------- | ----------------------- | 521| 1400003 | This display manager service works abnormally. | 522 523**Example** 524 525```ts 526import { display } from '@kit.ArkUI'; 527 528let data: display.FoldStatus = display.getFoldStatus(); 529console.info('Succeeded in obtaining fold status. Data: ' + JSON.stringify(data)); 530``` 531 532## display.getFoldDisplayMode<sup>10+</sup> 533getFoldDisplayMode(): FoldDisplayMode 534 535Obtains the display mode of the foldable device. 536 537**Atomic service API**: This API can be used in atomic services since API version 12. 538 539**System capability**: SystemCapability.Window.SessionManager 540 541**Return value** 542 543| Type| Description| 544| ----------------------------------------------- | ------------------------------------------------------- | 545| [FoldDisplayMode](#folddisplaymode10) | Display mode of the device.| 546 547**Error codes** 548 549For details about the error codes, see [Display Error Codes](errorcode-display.md). 550 551| ID| Error Message| 552| ------- | ----------------------- | 553| 1400003 | This display manager service works abnormally. | 554 555**Example** 556 557```ts 558import { display } from '@kit.ArkUI'; 559 560let data: display.FoldDisplayMode = display.getFoldDisplayMode(); 561console.info('Succeeded in obtaining fold display mode. Data: ' + JSON.stringify(data)); 562``` 563 564## display.getCurrentFoldCreaseRegion<sup>10+</sup> 565getCurrentFoldCreaseRegion(): FoldCreaseRegion 566 567Obtains the crease region of the foldable device in the current display mode. 568 569**Atomic service API**: This API can be used in atomic services since API version 12. 570 571**System capability**: SystemCapability.Window.SessionManager 572 573**Return value** 574 575| Type| Description| 576| ----------------------------------------------- | ------------------------------------------------------- | 577| [FoldCreaseRegion](#foldcreaseregion10) | Crease region of the device.| 578 579**Error codes** 580 581For details about the error codes, see [Display Error Codes](errorcode-display.md). 582 583| ID| Error Message| 584| ------- | ----------------------- | 585| 1400003 | This display manager service works abnormally. | 586 587**Example** 588 589```ts 590import { display } from '@kit.ArkUI'; 591 592let data: display.FoldCreaseRegion = display.getCurrentFoldCreaseRegion(); 593console.info('Succeeded in obtaining current fold crease region. Data: ' + JSON.stringify(data)); 594``` 595 596## display.on('foldStatusChange')<sup>10+</sup> 597 598on(type: 'foldStatusChange', callback: Callback<FoldStatus>): void 599 600Subscribes to fold status change events of the foldable device. 601 602Note that [display.on('foldDisplayModeChange')](#displayonfolddisplaymodechange10) subscribes to display mode change events of the foldable device. 603 604The two are different. In terms of time sequence, the fold status changes first, and the bottom layer matches the display mode status based on the fold status. 605 606To check whether the content is displayed on the inner or outer screen of the foldable device, use [display.on('foldDisplayModeChange')](#displayonfolddisplaymodechange10). 607 608**Atomic service API**: This API can be used in atomic services since API version 12. 609 610**System capability**: SystemCapability.Window.SessionManager 611 612**Parameters** 613 614| Name | Type | Mandatory| Description | 615| -------- |------------------------------------------| ---- | ------------------------------------------------------- | 616| type | string | Yes | Event type. The event **'foldStatusChange'** is triggered when the fold status of the device changes.| 617| callback | Callback<[FoldStatus](#foldstatus10)> | Yes | Callback used to return the fold status.| 618 619**Error codes** 620 621For details about the error codes, see [Universal Error Codes](../errorcode-universal.md) and [Display Error Codes](errorcode-display.md). 622 623| ID| Error Message| 624| ------- | ----------------------- | 625| 401 | Parameter error. Possible causes: 1.Mandatory parameters are left unspecified. 2.Incorrect parameter types.| 626| 1400003 | This display manager service works abnormally. | 627 628**Example** 629 630```ts 631import { Callback } from '@kit.BasicServicesKit'; 632 633/** 634 * The callback parameter used for subscription must be passed as an object. 635 * If an anonymous function is used for registration, a new underlying object is created each time the function is called, causing memory leakage. 636*/ 637let callback: Callback<display.FoldStatus> = (data: display.FoldStatus) => { 638 console.info('Listening enabled. Data: ' + JSON.stringify(data)); 639}; 640display.on('foldStatusChange', callback); 641``` 642 643## display.off('foldStatusChange')<sup>10+</sup> 644 645off(type: 'foldStatusChange', callback?: Callback<FoldStatus>): void 646 647Unsubscribes from fold status change events of the foldable device. 648 649**Atomic service API**: This API can be used in atomic services since API version 12. 650 651**System capability**: SystemCapability.Window.SessionManager 652 653**Parameters** 654 655| Name | Type | Mandatory| Description | 656| -------- |------------------------------------------| ---- | ------------------------------------------------------- | 657| type | string | Yes | Event type. The event **'foldStatusChange'** is triggered when the fold status of the device changes.| 658| callback | Callback<[FoldStatus](#foldstatus10)> | No | Callback used for unsubscription. If this parameter is not specified, all callbacks of the specified type will be unregistered.| 659 660**Error codes** 661 662For details about the error codes, see [Universal Error Codes](../errorcode-universal.md) and [Display Error Codes](errorcode-display.md). 663 664| ID| Error Message| 665| ------- | ----------------------- | 666| 401 | Parameter error. Possible causes: 1.Mandatory parameters are left unspecified. 2.Incorrect parameter types.| 667| 1400003 | This display manager service works abnormally. | 668 669**Example** 670 671```ts 672 673// Unregister all the callbacks that have been registered through on(). 674display.off('foldStatusChange'); 675 676let callback: Callback<display.FoldStatus> = (data: display.FoldStatus) => { 677 console.info('unregistering FoldStatus changes callback. Data: ' + JSON.stringify(data)); 678}; 679// Unregister the specified callback. 680display.off('foldStatusChange', callback); 681``` 682 683## display.on('foldAngleChange')<sup>12+</sup> 684 685on(type: 'foldAngleChange', callback: Callback<Array<number>>): void 686 687Subscribes to folding angle change events of the foldable device. 688 689**Atomic service API**: This API can be used in atomic services since API version 12. 690 691**System capability**: SystemCapability.Window.SessionManager 692 693**Parameters** 694 695| Name | Type | Mandatory| Description | 696| -------- |------------------------------------------| ---- | ------------------------------------------------------- | 697| type | string | Yes| Event type. The event **'foldAngleChange'** is triggered when the folding angle of the device changes.| 698| callback | Callback<Array<number>> | Yes| Callback used to return the folding angle (0–180 degrees). | 699 700**Error codes** 701 702For details about the error codes, see [Universal Error Codes](../errorcode-universal.md) and [Display Error Codes](errorcode-display.md). 703 704| ID| Error Message| 705| ------- | ----------------------- | 706| 401 | Parameter error. Possible causes: 1.Mandatory parameters are left unspecified. 2.Incorrect parameter types.| 707| 1400003 | This display manager service works abnormally. | 708 709**Example** 710 711```ts 712import { Callback } from '@kit.BasicServicesKit'; 713 714let callback: Callback<Array<number>> = (angles: Array<number>) => { 715 console.info('Listening fold angles length: ' + angles.length); 716}; 717display.on('foldAngleChange', callback); 718``` 719 720## display.off('foldAngleChange')<sup>12+</sup> 721 722off(type: 'foldAngleChange', callback?: Callback<Array<number>>): void 723 724Unsubscribes from folding angle change events of the foldable device. 725 726**Atomic service API**: This API can be used in atomic services since API version 12. 727 728**System capability**: SystemCapability.Window.SessionManager 729 730**Parameters** 731 732| Name | Type | Mandatory| Description | 733| -------- |-------------------------------------------| ---- | ------------------------------------------------------- | 734| type | string | Yes | Event type. The event **'foldAngleChange'** is triggered when the folding angle of the device changes.| 735| callback | Callback<Array<number>> | No | Callback used for unsubscription. If this parameter is not specified, all callbacks of the specified type will be unregistered.| 736 737**Error codes** 738 739For details about the error codes, see [Universal Error Codes](../errorcode-universal.md) and [Display Error Codes](errorcode-display.md). 740 741| ID| Error Message| 742| ------- | ----------------------- | 743| 401 | Parameter error. Possible causes: 1.Mandatory parameters are left unspecified. 2.Incorrect parameter types.| 744| 1400003 | This display manager service works abnormally. | 745 746**Example** 747 748```ts 749display.off('foldAngleChange'); 750``` 751 752## display.on('captureStatusChange')<sup>12+</sup> 753 754on(type: 'captureStatusChange', callback: Callback<boolean>): void 755 756Subscribes to screen capture, casting, or recording status changes. 757 758**Atomic service API**: This API can be used in atomic services since API version 12. 759 760**System capability**: SystemCapability.Window.SessionManager 761 762**Parameters** 763 764| Name | Type | Mandatory| Description | 765| -------- |-------------------------------------------| ---- | ------------------------------------------------------- | 766| type | string | Yes| Event type. The event **'captureStatusChange'** is triggered when the screen capture, casting, or recording status changes.| 767| callback | Callback<boolean> | Yes| Callback used to return the screen capture, casting, or recording status change. The value **true** means that the device starts screen capture, casting, or recording, and **false** means that the device stops screen capture, casting, or recording.| 768 769**Error codes** 770 771For details about the error codes, see [Universal Error Codes](../errorcode-universal.md) and [Display Error Codes](errorcode-display.md). 772 773| ID| Error Message| 774| ------- | ----------------------- | 775| 401 | Parameter error. Possible causes: 1.Mandatory parameters are left unspecified. 2.Incorrect parameter types.| 776| 1400003 | This display manager service works abnormally. | 777 778**Example** 779 780```ts 781import { Callback } from '@kit.BasicServicesKit'; 782 783let callback: Callback<boolean> = (captureStatus: boolean) => { 784 console.info('Listening capture status: ' + captureStatus); 785}; 786display.on('captureStatusChange', callback); 787``` 788 789## display.off('captureStatusChange')<sup>12+</sup> 790 791off(type: 'captureStatusChange', callback?: Callback<boolean>): void 792 793Unsubscribes from screen capture, casting, or recording status changes. 794 795**Atomic service API**: This API can be used in atomic services since API version 12. 796 797**System capability**: SystemCapability.Window.SessionManager 798 799**Parameters** 800 801| Name | Type | Mandatory| Description | 802| -------- |-------------------------------------------| ---- | ------------------------------------------------------- | 803| type | string | Yes| Event type. The event **'captureStatusChange'** is triggered when the screen capture, casting, or recording status changes.| 804| callback | Callback<boolean> | No| Callback used for unsubscription. If this parameter is not specified, all callbacks of the specified type will be unregistered.| 805 806**Error codes** 807 808For details about the error codes, see [Universal Error Codes](../errorcode-universal.md) and [Display Error Codes](errorcode-display.md). 809 810| ID| Error Message| 811| ------- | ----------------------- | 812| 401 | Parameter error. Possible causes: 1.Mandatory parameters are left unspecified. 2.Incorrect parameter types.| 813| 1400003 | This display manager service works abnormally. | 814 815**Example** 816 817```ts 818display.off('captureStatusChange'); 819``` 820 821## display.isCaptured<sup>12+</sup> 822isCaptured(): boolean 823 824Checks whether the display is being captured, projected, or recorded. 825 826**Atomic service API**: This API can be used in atomic services since API version 12. 827 828**System capability**: SystemCapability.Window.SessionManager 829 830**Return value** 831 832| Type| Description| 833| ----------------------------------------------- | ------------------------------------------------------- | 834| boolean | **true**: The display is being captured, projected, or recorded.<br> **false**: The display is not being captured, projected, or recorded.| 835 836**Error codes** 837 838For details about the error codes, see [Display Error Codes](errorcode-display.md). 839 840| ID| Error Message| 841| ------- | ----------------------- | 842| 1400003 | This display manager service works abnormally. | 843 844**Example** 845 846```ts 847import { display } from '@kit.ArkUI'; 848 849let ret: boolean = false; 850ret = display.isCaptured(); 851``` 852 853## display.on('foldDisplayModeChange')<sup>10+</sup> 854 855on(type: 'foldDisplayModeChange', callback: Callback<FoldDisplayMode>): void 856 857Subscribes to display mode change events of the foldable device. 858 859Subscribes to display mode change events of the foldable device. Note that [display.on('foldStatusChange')](#displayonfoldstatuschange10) subscribes to fold status change events of the foldable device. 860 861The two are different. In terms of time sequence, the fold status changes first, and the bottom layer matches the display mode status based on the fold status. 862 863**Atomic service API**: This API can be used in atomic services since API version 12. 864 865**System capability**: SystemCapability.Window.SessionManager 866 867**Parameters** 868 869| Name | Type | Mandatory| Description | 870| -------- |------------------------------------------| ---- | ------------------------------------------------------- | 871| type | string | Yes | Event type. The event **'foldDisplayModeChange'** is triggered when the display mode of the device changes.| 872| callback | Callback<[FoldDisplayMode](#folddisplaymode10)> | Yes | Callback used to return the display mode.| 873 874**Error codes** 875 876For details about the error codes, see [Universal Error Codes](../errorcode-universal.md) and [Display Error Codes](errorcode-display.md). 877 878| ID| Error Message| 879| ------- | ----------------------- | 880| 401 | Parameter error. Possible causes: 1.Mandatory parameters are left unspecified. 2.Incorrect parameter types.| 881| 1400003 | This display manager service works abnormally. | 882 883**Example** 884 885```ts 886import { Callback } from '@kit.BasicServicesKit'; 887 888/** 889 * The callback parameter used for subscription must be passed as an object. 890 * If an anonymous function is used for registration, a new underlying object is created each time the function is called, causing memory leakage. 891*/ 892let callback: Callback<display.FoldDisplayMode> = (data: display.FoldDisplayMode) => { 893 console.info('Listening enabled. Data: ' + JSON.stringify(data)); 894}; 895display.on('foldDisplayModeChange', callback); 896``` 897 898## display.off('foldDisplayModeChange')<sup>10+</sup> 899 900off(type: 'foldDisplayModeChange', callback?: Callback<FoldDisplayMode>): void 901 902Unsubscribes from display mode change events of the foldable device. 903 904**Atomic service API**: This API can be used in atomic services since API version 12. 905 906**System capability**: SystemCapability.Window.SessionManager 907 908**Parameters** 909 910| Name | Type | Mandatory| Description | 911| -------- |------------------------------------------| ---- | ------------------------------------------------------- | 912| type | string | Yes | Event type. The event **'foldDisplayModeChange'** is triggered when the display mode of the device changes.| 913| callback | Callback<[FoldDisplayMode](#folddisplaymode10)> | No | Callback used for unsubscription. If this parameter is not specified, all callbacks of the specified type will be unregistered.| 914 915**Error codes** 916 917For details about the error codes, see [Universal Error Codes](../errorcode-universal.md) and [Display Error Codes](errorcode-display.md). 918 919| ID| Error Message| 920| ------- | ----------------------- | 921| 401 | Parameter error. Possible causes: 1.Mandatory parameters are left unspecified. 2.Incorrect parameter types.| 922| 1400003 | This display manager service works abnormally. | 923 924**Example** 925 926```ts 927 928// Unregister all the callbacks that have been registered through on(). 929display.off('foldDisplayModeChange'); 930 931let callback: Callback<display.FoldDisplayMode> = (data: display.FoldDisplayMode) => { 932 console.info('unregistering FoldDisplayMode changes callback. Data: ' + JSON.stringify(data)); 933}; 934// Unregister the specified callback. 935display.off('foldDisplayModeChange', callback); 936``` 937 938 939## display.getDefaultDisplay<sup>(deprecated)</sup> 940 941getDefaultDisplay(callback: AsyncCallback<Display>): void 942 943Obtains the default display object. This API uses an asynchronous callback to return the result. 944 945> **NOTE** 946> 947> This API is supported since API version 7 and deprecated since API version 9. You are advised to use [getDefaultDisplaySync()](#displaygetdefaultdisplaysync9) instead. 948 949**System capability**: SystemCapability.WindowManager.WindowManager.Core 950 951**Parameters** 952 953| Name| Type| Mandatory| Description| 954| -------- | -------- | -------- | -------- | 955| callback | AsyncCallback<[Display](#display)> | Yes| Callback used to return the default display object.| 956 957**Example** 958 959```ts 960import { BusinessError } from '@kit.BasicServicesKit'; 961 962let displayClass: display.Display | null = null; 963display.getDefaultDisplay((err: BusinessError, data: display.Display) => { 964 const errCode: number = err.code; 965 if (errCode) { 966 console.error(`Failed to obtain the default display object. Code: ${err.code}, message: ${err.message}`); 967 return; 968 } 969 console.info('Succeeded in obtaining the default display object. Data:' + JSON.stringify(data)); 970 displayClass = data; 971}); 972``` 973 974## display.getDefaultDisplay<sup>(deprecated)</sup> 975 976getDefaultDisplay(): Promise<Display> 977 978Obtains the default display object. This API uses a promise to return the result. 979 980> **NOTE** 981> 982> This API is supported since API version 7 and deprecated since API version 9. You are advised to use [getDefaultDisplaySync()](#displaygetdefaultdisplaysync9) instead. 983 984**System capability**: SystemCapability.WindowManager.WindowManager.Core 985 986**Return value** 987 988| Type | Description | 989| ---------------------------------- | ---------------------------------------------- | 990| Promise<[Display](#display)> | Promise used to return the default display object.| 991 992**Example** 993 994```ts 995import { BusinessError } from '@kit.BasicServicesKit'; 996 997let displayClass: display.Display | null = null; 998let promise: Promise<display.Display> = display.getDefaultDisplay(); 999promise.then((data: display.Display) => { 1000 displayClass = data; 1001 console.info('Succeeded in obtaining the default display object. Data:' + JSON.stringify(data)); 1002}).catch((err: BusinessError) => { 1003 console.error(`Failed to obtain the default display object. Code: ${err.code}, message: ${err.message}`); 1004}); 1005``` 1006 1007## display.getAllDisplay<sup>(deprecated)</sup> 1008 1009getAllDisplay(callback: AsyncCallback<Array<Display>>): void 1010 1011Obtains all display objects. This API uses an asynchronous callback to return the result. 1012 1013> **NOTE** 1014> 1015> This API is supported since API version 7 and deprecated since API version 9. You are advised to use [getAllDisplays()](#displaygetalldisplays9) instead. 1016 1017**System capability**: SystemCapability.WindowManager.WindowManager.Core 1018 1019**Parameters** 1020 1021| Name | Type | Mandatory| Description | 1022| -------- | ---------------------------------------------------- | ---- | ------------------------------- | 1023| callback | AsyncCallback<Array<[Display](#display)>> | Yes | Callback used to return all the display objects.| 1024 1025**Example** 1026 1027```ts 1028import { BusinessError } from '@kit.BasicServicesKit'; 1029 1030display.getAllDisplay((err: BusinessError, data: Array<display.Display>) => { 1031 const errCode: number = err.code; 1032 if (errCode) { 1033 console.error(`Failed to obtain all the display objects. Code: ${err.code}, message: ${err.message}`); 1034 return; 1035 } 1036 console.info('Succeeded in obtaining all the display objects. Data: ' + JSON.stringify(data)); 1037}); 1038``` 1039 1040## display.getAllDisplay<sup>(deprecated)</sup> 1041 1042getAllDisplay(): Promise<Array<Display>> 1043 1044Obtains all display objects. This API uses a promise to return the result. 1045 1046> **NOTE** 1047> 1048> This API is supported since API version 7 and deprecated since API version 9. You are advised to use [getAllDisplays()](#displaygetalldisplays9-1) instead. 1049 1050**System capability**: SystemCapability.WindowManager.WindowManager.Core 1051 1052**Return value** 1053 1054| Type | Description | 1055| ----------------------------------------------- | ------------------------------------------------------- | 1056| Promise<Array<[Display](#display)>> | Promise used to return all the display objects.| 1057 1058**Example** 1059 1060```ts 1061import { BusinessError } from '@kit.BasicServicesKit'; 1062 1063let promise: Promise<Array<display.Display>> = display.getAllDisplay(); 1064promise.then((data: Array<display.Display>) => { 1065 console.info('Succeeded in obtaining all the display objects. Data: ' + JSON.stringify(data)); 1066}).catch((err: BusinessError) => { 1067 console.error(`Failed to obtain all the display objects. Code: ${err.code}, message: ${err.message}`); 1068}); 1069``` 1070 1071## Display 1072Implements a **Display** instance, with properties and APIs defined. 1073 1074Before calling any API in **Display**, you must use [getAllDisplays()](#displaygetalldisplays9) or [getDefaultDisplaySync()](#displaygetdefaultdisplaysync9) to obtain a **Display** instance. 1075 1076### Properties 1077 1078**System capability**: SystemCapability.WindowManager.WindowManager.Core 1079 1080| Name| Type| Read-Only| Optional| Description | 1081| -------- | -------- | -------- | -------- |---------------------------------------------------------------------------------------------------------------| 1082| id | number | Yes| No| ID of the display. The value must be an integer.<br>**Atomic service API**: This API can be used in atomic services since API version 12. | 1083| name | string | Yes| No| Name of the display.<br>**Atomic service API**: This API can be used in atomic services since API version 12. | 1084| alive | boolean | Yes| No| Whether the display is alive.<br>**Atomic service API**: This API can be used in atomic services since API version 12. | 1085| state | [DisplayState](#displaystate) | Yes| No| State of the display.<br>**Atomic service API**: This API can be used in atomic services since API version 12. | 1086| refreshRate | number | Yes| No| Refresh rate of the display, in hz. The value must be an integer.<br>**Atomic service API**: This API can be used in atomic services since API version 12. | 1087| rotation | number | Yes| No| Clockwise rotation angle of the display.<br>The value **0** indicates that the display rotates clockwise by 0°.<br>The value **1** indicates that the display rotates clockwise by 90°.<br>The value **2** indicates that the display rotates clockwise by 180°.<br>The value **3** indicates that the display rotates clockwise by 270°.<br>**Atomic service API**: This API can be used in atomic services since API version 11.| 1088| width | number | Yes| No| Width of the display, in px. The value must be an integer.<br>**Atomic service API**: This API can be used in atomic services since API version 11. | 1089| height | number | Yes| No| Height of the display, in px. The value must be an integer.<br>**Atomic service API**: This API can be used in atomic services since API version 11. | 1090| densityDPI | number | Yes| No| Physical pixel density of the display, that is, the number of pixels per inch. The value is a floating point number, in px. Generally, the value is **160.0** or **480.0**. The actual value depends on the optional values provided by the device in use.<br>**Atomic service API**: This API can be used in atomic services since API version 12. | 1091| orientation<sup>10+</sup> | [Orientation](#orientation10) | Yes| No| Orientation of the display.<br>**Atomic service API**: This API can be used in atomic services since API version 12. | 1092| densityPixels | number | Yes| No| Logical pixel density of the display, which is the scaling coefficient between physical pixels and logical pixels. The calculation method is as follows:<br><br>The value is a floating point number and is restricted by the range of **densityDPI**. The value range is [0.5, 4.0]. Generally, the value is **1.0** or **3.0**. The actual value depends on the density DPI provided by the device in use.<br>**Atomic service API**: This API can be used in atomic services since API version 11. | 1093| scaledDensity | number | Yes| No| Scaling factor for fonts displayed on the display. The value must be a floating point number. Generally, the value is the same as that of **densityPixels**.<br>**Atomic service API**: This API can be used in atomic services since API version 12. | 1094| xDPI | number | Yes| No| Exact physical pixels per inch of the display in the X dimension. The value must be a floating point number.<br>**Atomic service API**: This API can be used in atomic services since API version 12. | 1095| yDPI | number | Yes| No| Exact physical pixels per inch of the display in the Y dimension. The value must be a floating point number.<br>**Atomic service API**: This API can be used in atomic services since API version 12. | 1096| colorSpaces<sup>11+</sup> | Array<[colorSpaceManager.ColorSpace](../apis-arkgraphics2d/js-apis-colorSpaceManager.md)> | Yes| No| All color spaces supported by the display.<br>**Atomic service API**: This API can be used in atomic services since API version 12. | 1097| hdrFormats<sup>11+</sup> | Array<[hdrCapability.HDRFormat](../apis-arkgraphics2d/js-apis-hdrCapability.md)> | Yes| No| All HDR formats supported by the display.<br>**Atomic service API**: This API can be used in atomic services since API version 12. | 1098| availableWidth<sup>12+</sup> | number | Yes| No| Width of the available area on a 2-in-1 device, in px. The value is an integer greater than 0.<br>**Atomic service API**: This API can be used in atomic services since API version 12. | 1099| availableHeight<sup>12+</sup> | number | Yes| No| Height of the available area on a 2-in-1 device, in px. The value is an integer greater than 0.<br>**Atomic service API**: This API can be used in atomic services since API version 12. | 1100 1101### getCutoutInfo<sup>9+</sup> 1102getCutoutInfo(callback: AsyncCallback<CutoutInfo>): void 1103 1104Obtains the cutout information of the display. This API uses an asynchronous callback to return the result. You are advised not to use the cutout area during application layout. 1105 1106**Atomic service API**: This API can be used in atomic services since API version 12. 1107 1108**System capability**: SystemCapability.WindowManager.WindowManager.Core 1109 1110**Parameters** 1111 1112| Name | Type | Mandatory| Description | 1113| ----------- | --------------------------- | ---- | ------------------------------------------------------------ | 1114| callback | AsyncCallback<[CutoutInfo](#cutoutinfo9)> | Yes | Callback used to return the **CutoutInfo** object.| 1115 1116**Error codes** 1117 1118For details about the error codes, see [Display Error Codes](errorcode-display.md). 1119 1120| ID| Error Message| 1121| ------- | ----------------------- | 1122| 1400001 | Invalid display or screen. | 1123 1124**Example** 1125 1126```ts 1127import { BusinessError } from '@kit.BasicServicesKit'; 1128 1129let displayClass: display.Display | null = null; 1130displayClass = display.getDefaultDisplaySync(); 1131 1132displayClass.getCutoutInfo((err: BusinessError, data: display.CutoutInfo) => { 1133 const errCode: number = err.code; 1134 if (errCode) { 1135 console.error(`Failed to get cutoutInfo. Code: ${err.code}, message: ${err.message}`); 1136 return; 1137 } 1138 console.info('Succeeded in getting cutoutInfo. data: ' + JSON.stringify(data)); 1139}); 1140``` 1141### getCutoutInfo<sup>9+</sup> 1142getCutoutInfo(): Promise<CutoutInfo> 1143 1144Obtains the cutout information of the display. This API uses a promise to return the result. You are advised not to use the cutout area during application layout. 1145 1146**Atomic service API**: This API can be used in atomic services since API version 12. 1147 1148**System capability**: SystemCapability.WindowManager.WindowManager.Core 1149 1150**Return value** 1151 1152| Type | Description | 1153| ------------------- | ------------------------- | 1154| Promise<[CutoutInfo](#cutoutinfo9)> | Promise used to return the **CutoutInfo** object.| 1155 1156**Error codes** 1157 1158For details about the error codes, see [Display Error Codes](errorcode-display.md). 1159 1160| ID| Error Message| 1161| ------- | ----------------------- | 1162| 1400001 | Invalid display or screen. | 1163 1164**Example** 1165 1166```ts 1167import { BusinessError } from '@kit.BasicServicesKit'; 1168 1169let displayClass: display.Display | null = null; 1170displayClass = display.getDefaultDisplaySync(); 1171let promise: Promise<display.CutoutInfo> = displayClass.getCutoutInfo(); 1172promise.then((data: display.CutoutInfo) => { 1173 console.info('Succeeded in getting cutoutInfo. Data: ' + JSON.stringify(data)); 1174}).catch((err: BusinessError) => { 1175 console.error(`Failed to obtain all the display objects. Code: ${err.code}, message: ${err.message}`); 1176}); 1177``` 1178 1179### getAvailableArea<sup>12+</sup> 1180getAvailableArea(): Promise<Rect> 1181 1182Obtains the available area of the display of the current device. This API uses a promise to return the result. 1183 1184**Atomic service API**: This API can be used in atomic services since API version 12. 1185 1186**System capability**: SystemCapability.Window.SessionManager 1187 1188**Return value** 1189 1190| Type | Description | 1191| ------------------- | ------------------------- | 1192| Promise<[Rect](#rect9)> | Promise used to return the available area, which is a rectangle.| 1193 1194**Error codes** 1195 1196For details about the error codes, see [Universal Error Codes](../errorcode-universal.md) and [Display Error Codes](errorcode-display.md). 1197 1198| ID| Error Message| 1199| ------- | ----------------------- | 1200| 801 | Capability not supported. Failed to call the API due to limited device capabilities. | 1201| 1400001 | Invalid display or screen. | 1202 1203**Example** 1204 1205```ts 1206import { BusinessError } from '@kit.BasicServicesKit'; 1207import { display } from '@kit.ArkUI'; 1208 1209let displayClass: display.Display | null = null; 1210try { 1211 displayClass = display.getDefaultDisplaySync(); 1212 let promise = displayClass.getAvailableArea(); 1213 promise.then((data) => { 1214 console.info('Succeeded get the available area in this display. data: ' + JSON.stringify(data)); 1215 }).catch((err: BusinessError) => { 1216 console.error(`Failed to get the available area in this display. Code: ${err.code}, message: ${err.message}`); 1217 }) 1218} catch (exception) { 1219 console.error(`Failed to obtain the default display object. Code: ${exception.code}, message: ${exception.message}`); 1220} 1221``` 1222 1223### on('availableAreaChange')<sup>12+</sup> 1224on(type: 'availableAreaChange', callback: Callback<Rect>): void 1225 1226Subscribes to changes of the available area on the display of the current device. This API uses an asynchronous callback to return the result. 1227 1228**Atomic service API**: This API can be used in atomic services since API version 12. 1229 1230**System capability**: SystemCapability.Window.SessionManager 1231 1232**Parameters** 1233 1234| Name | Type | Mandatory| Description | 1235| -------- |------------------------------------------| ---- | ------------------------------------------------------- | 1236| type | string | Yes | Event type. The event **'availableAreaChange'** is triggered when the available area of the display changes.| 1237| callback | Callback<[Rect](#rect9)> | Yes | Callback used to return the new available area.| 1238 1239**Error codes** 1240 1241For details about the error codes, see [Universal Error Codes](../errorcode-universal.md) and [Display Error Codes](errorcode-display.md). 1242 1243| ID| Error Message| 1244| ------- | ----------------------- | 1245| 401 | Parameter error. Possible causes: 1.Mandatory parameters are left unspecified. 2.Incorrect parameter types.| 1246| 801 | Capability not supported. Failed to call the API due to limited device capabilities. | 1247| 1400003 | This display manager service works abnormally. | 1248 1249**Example** 1250 1251```ts 1252import { Callback } from '@kit.BasicServicesKit'; 1253import { display } from '@kit.ArkUI'; 1254 1255let callback: Callback<display.Rect> = (data: display.Rect) => { 1256 console.info('Listening enabled. Data: ' + JSON.stringify(data)); 1257}; 1258let displayClass: display.Display | null = null; 1259try { 1260 displayClass = display.getDefaultDisplaySync(); 1261 displayClass.on("availableAreaChange", callback); 1262} catch (exception) { 1263 console.error(`Failed to register callback. Code: ${exception.code}, message: ${exception.message}`); 1264} 1265``` 1266 1267### off('availableAreaChange')<sup>12+</sup> 1268 1269off(type: 'availableAreaChange', callback?: Callback<Rect>): void 1270 1271Unsubscribes from changes of the available area on the display of the current device. 1272 1273**Atomic service API**: This API can be used in atomic services since API version 12. 1274 1275**System capability**: SystemCapability.Window.SessionManager 1276 1277**Parameters** 1278 1279| Name | Type | Mandatory| Description | 1280| -------- |------------------------------------------| ---- | ------------------------------------------------------- | 1281| type | string | Yes | Event type. The event **'availableAreaChange'** is triggered when the available area of the display changes.| 1282| callback | Callback<[Rect](#rect9)> | No | Callback used for unsubscription. If no value is passed in, all subscriptions to the specified event are canceled.| 1283 1284**Error codes** 1285 1286For details about the error codes, see [Universal Error Codes](../errorcode-universal.md) and [Display Error Codes](errorcode-display.md). 1287 1288| ID| Error Message| 1289| ------- | ----------------------- | 1290| 401 | Parameter error. Possible causes: 1.Mandatory parameters are left unspecified. 2.Incorrect parameter types.| 1291| 801 | Capability not supported. Failed to call the API due to limited device capabilities. | 1292| 1400003 | This display manager service works abnormally. | 1293 1294**Example** 1295 1296```ts 1297import { Callback } from '@kit.BasicServicesKit'; 1298import { display } from '@kit.ArkUI'; 1299 1300let callback: Callback<display.Rect> = (data: display.Rect) => { 1301 console.info('Listening enabled. Data: ' + JSON.stringify(data)); 1302}; 1303let displayClass: display.Display | null = null; 1304try { 1305 displayClass = display.getDefaultDisplaySync(); 1306 displayClass.off("availableAreaChange", callback); 1307} catch (exception) { 1308 console.error(`Failed to unregister callback. Code: ${exception.code}, message: ${exception.message}`); 1309} 1310``` 1311
