@ohos.application.Ability (Ability)

The Ability module manages the ability lifecycle and context, such as creating and destroying an ability, and dumping client information.

This module provides the following common ability-related functions:

• Caller: implements sending of sequenceable data to the target ability when an ability (caller ability) invokes the target ability (callee ability).
• Callee: implements callbacks for registration and deregistration of caller notifications.

NOTE

The APIs of this module are deprecated since API version 9. You are advised to use @ohos.app.ability.UIAbility (UIAbility) instead.

The initial APIs of this module are supported since API version 9. Newly added APIs will be marked with a superscript to indicate their earliest API version.

The APIs of this module can be used only in the stage model.

Modules to Import

import UIAbility from '@ohos.application.Ability';

Attributes

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Ability.onCreate

onCreate(want: Want, param: AbilityConstant.LaunchParam): void;

Called to initialize the service logic when an ability is created.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Example

  export default class EntryAbility extends UIAbility {
      onCreate(want, param) {
          console.log('onCreate, want:' + want.abilityName);
      }
  }

Ability.onWindowStageCreate

onWindowStageCreate(windowStage: window.WindowStage): void

Called when a WindowStage is created for this ability.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Example

  export default class EntryAbility extends UIAbility {
      onWindowStageCreate(windowStage) {
          console.log('onWindowStageCreate');
      }
  }

Ability.onWindowStageDestroy

onWindowStageDestroy(): void

Called when the WindowStage is destroyed for this ability.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Example

  export default class EntryAbility extends UIAbility {
      onWindowStageDestroy() {
          console.log('onWindowStageDestroy');
      }
  }

Ability.onWindowStageRestore

onWindowStageRestore(windowStage: window.WindowStage): void

Called when the WindowStage is restored during the migration of this ability, which is a multi-instance ability.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Example

  export default class EntryAbility extends UIAbility {
      onWindowStageRestore(windowStage) {
          console.log('onWindowStageRestore');
      }
  }

Ability.onDestroy

onDestroy(): void;

Called when this ability is destroyed to clear resources.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Example

  export default class EntryAbility extends UIAbility {
      onDestroy() {
          console.log('onDestroy');
      }
  }

Ability.onForeground

onForeground(): void;

Called when this ability is switched from the background to the foreground.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Example

  export default class EntryAbility extends UIAbility {
      onForeground() {
          console.log('onForeground');
      }
  }

Ability.onBackground

onBackground(): void;

Called when this ability is switched from the foreground to the background.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Example

  export default class EntryAbility extends UIAbility {
      onBackground() {
          console.log('onBackground');
      }
  }

Ability.onContinue

onContinue(wantParam : {[key: string]: any}): AbilityConstant.OnContinueResult;

Called to save data during the ability migration preparation process.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Return value

Example

  import AbilityConstant from "@ohos.app.ability.AbilityConstant";
  
  export default class EntryAbility extends UIAbility {
      onContinue(wantParams) {
          console.log('onContinue');
          wantParams["myData"] = "my1234567";
          return AbilityConstant.OnContinueResult.AGREE;
      }
  }

Ability.onNewWant

onNewWant(want: Want, launchParams: AbilityConstant.LaunchParam): void;

Called when a new Want is passed in and this UIAbility is started again.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Example

  export default class EntryAbility extends UIAbility {
      onNewWant(want, launchParams) {
          console.log('onNewWant, want:' + want.abilityName);
          console.log('onNewWant, launchParams:' + JSON.stringify(launchParams));
      }
  }

Ability.onConfigurationUpdated

onConfigurationUpdated(config: Configuration): void;

Called when the global configuration is updated.

System capability: SystemCapability.Ability.AbilityRuntime.Core

Parameters

Example

  export default class EntryAbility extends UIAbility {
      onConfigurationUpdated(config) {
          console.log('onConfigurationUpdated, language:' + config.language);
      }
  }

Ability.dump

dump(params: Array<string>): Array<string>;

Dumps client information.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Example

  export default class EntryAbility extends UIAbility {
      dump(params) {
          console.log('dump, params:' + JSON.stringify(params));
          return ["params"]
      }
  }

Ability.onMemoryLevel

onMemoryLevel(level: AbilityConstant.MemoryLevel): void;

Called when the system has decided to adjust the memory level. For example, this API can be used when there is not enough memory to run as many background processes as possible.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Example

  export default class EntryAbility extends UIAbility {
    onMemoryLevel(level) {
        console.log('onMemoryLevel, level:' + JSON.stringify(level));
    } 
  }

Ability.onSaveState

onSaveState(reason: AbilityConstant.StateType, wantParam : {[key: string]: any}): AbilityConstant.OnSaveResult;

Called when the framework automatically saves the ability state in the case of an application fault. This API is used together with appRecovery.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Return value

Example

import AbilityConstant from '@ohos.app.ability.AbilityConstant';

export default class EntryAbility extends UIAbility {
    onSaveState(reason, wantParam) {
        console.log('onSaveState');
        wantParam["myData"] = "my1234567";
        return AbilityConstant.OnSaveResult.RECOVERY_AGREE;
    }
}

Caller

Implements sending of sequenceable data to the target ability when an ability (caller ability) invokes the target ability (callee ability).

Caller.call

call(method: string, data: rpc.Sequenceable): Promise&lt;void&gt;;

Sends sequenceable data to the target ability.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Return value

Error codes

Example

  import UIAbility from '@ohos.app.ability.UIAbility';
  
  class MyMessageAble{ // Custom sequenceable data structure.
    name:""
    str:""
    num: 1
    constructor(name, str) {
      this.name = name;
      this.str = str;
    }
    marshalling(messageParcel) {
      messageParcel.writeInt(this.num);
      messageParcel.writeString(this.str);
      console.log('MyMessageAble marshalling num[' + this.num + '] str[' + this.str + ']');
      return true;
    }
    unmarshalling(messageParcel) {
      this.num = messageParcel.readInt();
      this.str = messageParcel.readString();
      console.log('MyMessageAble unmarshalling num[' + this.num + '] str[' + this.str + ']');
      return true;
    }
  };
  var method = 'call_Function'; // Notification message string negotiated by the two abilities
  var caller;
  export default class EntryAbility extends UIAbility {
    onWindowStageCreate(windowStage) {
      this.context.startAbilityByCall({
        bundleName: "com.example.myservice",
        abilityName: "EntryAbility",
        deviceId: ""
      }).then((obj) => {
        caller = obj;
        let msg = new MyMessageAble("msg", "world"); // See the definition of Sequenceable.
        caller.call(method, msg)
          .then(() => {
            console.log('Caller call() called');
          })
          .catch((callErr) => {
            console.log('Caller.call catch error, error.code: ' + JSON.stringify(callErr.code) +
              ' error.message: ' + JSON.stringify(callErr.message));
          });
      }).catch((err) => {
        console.log('Caller GetCaller error, error.code: ' + JSON.stringify(err.code) +
          ' error.message: ' + JSON.stringify(err.message));
      });
    }
  }

Caller.callWithResult

callWithResult(method: string, data: rpc.Sequenceable): Promise&lt;rpc.MessageParcel&gt;;

Sends sequenceable data to the target ability and obtains the sequenceable data returned by the target ability.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Return value

Error codes

Example

  import UIAbility from '@ohos.app.ability.UIAbility';
  
  class MyMessageAble{
    name:""
    str:""
    num: 1
    constructor(name, str) {
      this.name = name;
      this.str = str;
    }
    marshalling(messageParcel) {
      messageParcel.writeInt(this.num);
      messageParcel.writeString(this.str);
      console.log('MyMessageAble marshalling num[' + this.num + '] str[' + this.str + ']');
      return true;
    }
    unmarshalling(messageParcel) {
      this.num = messageParcel.readInt();
      this.str = messageParcel.readString();
      console.log('MyMessageAble unmarshalling num[' + this.num + '] str[' + this.str + ']');
      return true;
    }
  };
  var method = 'call_Function';
  var caller;
  export default class EntryAbility extends UIAbility {
    onWindowStageCreate(windowStage) {
      this.context.startAbilityByCall({
        bundleName: "com.example.myservice",
        abilityName: "EntryAbility",
        deviceId: ""
      }).then((obj) => {
        caller = obj;
        let msg = new MyMessageAble(1, "world");
        caller.callWithResult(method, msg)
          .then((data) => {
            console.log('Caller callWithResult() called');
            let retmsg = new MyMessageAble(0, "");
            data.readSequenceable(retmsg);
          })
          .catch((callErr) => {
            console.log('Caller.callWithResult catch error, error.code: ' + JSON.stringify(callErr.code) +
              ' error.message: ' + JSON.stringify(callErr.message));
          });
      }).catch((err) => {
        console.log('Caller GetCaller error, error.code: ' + JSON.stringify(err.code) +
          ' error.message: ' + JSON.stringify(err.message));
      });
    }
  }

Caller.release

release(): void;

Releases the caller interface of the target ability.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Error codes

Example

  import UIAbility from '@ohos.app.ability.UIAbility';
  
  var caller;
  
  export default class EntryAbility extends UIAbility {
    onWindowStageCreate(windowStage) {
      this.context.startAbilityByCall({
        bundleName: "com.example.myservice",
        abilityName: "EntryAbility",
        deviceId: ""
      }).then((obj) => {
        caller = obj;
        try {
          caller.release();
        } catch (releaseErr) {
          console.log('Caller.release catch error, error.code: ' + JSON.stringify(releaseErr.code) +
            ' error.message: ' + JSON.stringify(releaseErr.message));
        }
      }).catch((err) => {
        console.log('Caller GetCaller error, error.code: ' + JSON.stringify(err.code) +
          ' error.message: ' + JSON.stringify(err.message));
      });
    }
  }

Caller.onRelease

onRelease(callback: OnReleaseCallBack): void;

Registers a callback that is invoked when the stub on the target ability is disconnected.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Example

  import UIAbility from '@ohos.app.ability.UIAbility';
  
  var caller;
  
  export default class EntryAbility extends UIAbility {
    onWindowStageCreate(windowStage) {
      this.context.startAbilityByCall({
        bundleName: "com.example.myservice",
        abilityName: "EntryAbility",
        deviceId: ""
      }).then((obj) => {
          caller = obj;
          try {
            caller.onRelease((str) => {
                console.log(' Caller OnRelease CallBack is called ' + str);
            });
          } catch (error) {
            console.log('Caller.on catch error, error.code: ' + JSON.stringify(error.code) +
              ' error.message: ' + JSON.stringify(error.message));
          }
      }).catch((err) => {
        console.log('Caller GetCaller error, error.code: ' + JSON.stringify(err.code) +
          ' error.message: ' + JSON.stringify(err.message));
      });
    }
  }

Callee

Implements callbacks for caller notification registration and deregistration.

Callee.on

on(method: string, callback: CalleeCallBack): void;

Registers a caller notification callback, which is invoked when the target ability registers a function.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Error codes

Example

  import UIAbility from '@ohos.app.ability.UIAbility';
  class MyMessageAble{
      name:""
      str:""
      num: 1
      constructor(name, str) {
        this.name = name;
        this.str = str;
      }
      marshalling(messageParcel) {
          messageParcel.writeInt(this.num);
          messageParcel.writeString(this.str);
          console.log('MyMessageAble marshalling num[' + this.num + '] str[' + this.str + ']');
          return true;
      }
      unmarshalling(messageParcel) {
          this.num = messageParcel.readInt();
          this.str = messageParcel.readString();
          console.log('MyMessageAble unmarshalling num[' + this.num + '] str[' + this.str + ']');
          return true;
      }
  };
  var method = 'call_Function';
  function funcCallBack(pdata) {
      console.log('Callee funcCallBack is called ' + pdata);
      let msg = new MyMessageAble("test", "");
      pdata.readSequenceable(msg);
      return new MyMessageAble("test1", "Callee test");
  }
  export default class EntryAbility extends UIAbility {
    onCreate(want, launchParam) {
      console.log('Callee onCreate is called');
      try {
        this.callee.on(method, funcCallBack);
      } catch (error) {
        console.log('Callee.on catch error, error.code: ' + JSON.stringify(error.code) +
          ' error.message: ' + JSON.stringify(error.message));
      }
    }
  }

Callee.off

off(method: string): void;

Deregisters a caller notification callback, which is invoked when the target ability registers a function.

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

Parameters

Error codes

Example

  import UIAbility from '@ohos.app.ability.UIAbility';
  
  var method = 'call_Function';
  
  export default class EntryAbility extends UIAbility {
    onCreate(want, launchParam) {
      console.log('Callee onCreate is called');
      try {
        this.callee.off(method);
      } catch (error) {
        console.log('Callee.off catch error, error.code: ' + JSON.stringify(error.code) +
          ' error.message: ' + JSON.stringify(error.message));
      }
    }
  }

OnReleaseCallBack

(msg: string): void;

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

CalleeCallBack

(indata: rpc.MessageParcel): rpc.Sequenceable;

System capability: SystemCapability.Ability.AbilityRuntime.AbilityCore

你可能感兴趣的鸿蒙文章

harmony 鸿蒙APIs

harmony 鸿蒙System Common Events

harmony 鸿蒙System Common Events

harmony 鸿蒙API Reference Document Description

harmony 鸿蒙BundleStatusCallback

harmony 鸿蒙@ohos.bundle.innerBundleManager (innerBundleManager)

harmony 鸿蒙@ohos.distributedBundle (Distributed Bundle Management)

harmony 鸿蒙@ohos.bundle (Bundle)

harmony 鸿蒙@ohos.enterprise.EnterpriseAdminExtensionAbility (EnterpriseAdminExtensionAbility)

harmony 鸿蒙@ohos.WorkSchedulerExtensionAbility (Work Scheduler Callbacks)