# AbilityContext

> ![icon-note.gif](public_sys-resources/icon-note.gif) **NOTE**
> The initial APIs of this module are supported since API 9. Newly added APIs will be marked with a superscript to indicate their earliest API version.


Implements the ability context. This module is inherited from **Context**.


## Usage


Before using the **AbilityContext** module, you must define a child class that inherits from **Ability**.


  
```
import Ability from '@ohos.application.Ability'
class MainAbility extends Ability {
    onWindowStageCreate(windowStage) {
        let context = this.context;
    }
}
```


## Attributes

| Name| Type| Readable| Writable| Description| 
| -------- | -------- | -------- | -------- | -------- |
| abilityInfo | AbilityInfo | Yes| No| Ability information.| 
| currentHapModuleInfo | HapModuleInfo | Yes| No| Information about the current HAP.| 


## startAbility

startAbility(want: Want, callback: AsyncCallback<void>): void

Starts an ability. This method uses a callback to return the result.

**System capabilities**

SystemCapability.Ability.AbilityRuntime.Core

- Parameters
  | Name| Type| Mandatory| Description| 
  | -------- | -------- | -------- | -------- |
  | want | [Want](js-apis-featureAbility.md#Want)| Yes| Information about the **Want** used for starting an ability.| 
  | callback | AsyncCallback<void> | Yes| Callback used to return the result.| 

- Example
  ```
  var want = {
  	"deviceId": "",
  	"bundleName": "com.extreme.test",
  	"abilityName": "com.extreme.test.MainAbility"
  };
  this.context.startAbility(want, (error) => {
      console.log("error.code = " + error.code)
  })
  ```


## startAbility

startAbility(want: Want, options: StartOptions, callback: AsyncCallback<void>): void

Starts an ability. This method uses a callback to return the result.

**System capabilities**

SystemCapability.Ability.AbilityRuntime.Core

- Parameters
    | Name| Type| Mandatory| Description| 
  | -------- | -------- | -------- | -------- |
  | want | [Want](js-apis-featureAbility.md#Want) | Yes| Information about the **Want** used for starting an ability.| 
  | options | StartOptions | Yes| Parameters used for starting the ability.|
  | callback | AsyncCallback<void> | Yes| Callback used to return the result.| 

- Example
    
  ```
  var want = {
  	"deviceId": "",
  	"bundleName": "com.extreme.test",
  	"abilityName": "com.extreme.test.MainAbility"
  };
  var options = {
  	windowMode: 0,
  };
  this.context.startAbility(want, options, (error) => {
      console.log("error.code = " + error.code)
  })
  ```


## startAbility

startAbility(want: Want, options: StartOptions): Promise<void>;

Starts an ability. This method uses a promise to return the result.

**System capabilities**

SystemCapability.Ability.AbilityRuntime.Core

- Parameters
  | Name| Type| Mandatory| Description| 
  | -------- | -------- | -------- | -------- |
  | want | [Want](js-apis-featureAbility.md#Want)| Yes| Information about the **Want** used for starting an ability.| 
  | options | StartOptions | Yes| Parameters used for starting the ability.|

- Return value
  | Type| Description| 
  | -------- | -------- |
  | Promise<void> | Promise used to return the result.| 

- Example
  ```
  var want = {
  	"deviceId": "",
  	"bundleName": "com.extreme.test",
  	"abilityName": "com.extreme.test.MainAbility"
  };
  var options = {
  	windowMode: 0,
  };
  this.context.startAbility(want, options)
  .then((data) => {
      console.log('Operation successful.')
  }).catch((error) => {
      console.log('Operation failed.');
  })
  ```


## startAbilityForResult

startAbilityForResult(want: Want, callback: AsyncCallback<AbilityResult>): void;

Starts an ability. This method uses a callback to return the execution result when the ability is terminated.

**System capabilities**

SystemCapability.Ability.AbilityRuntime.Core

- Parameters
  | Name| Type| Mandatory| Description|
  | -------- | -------- | -------- | -------- |
  | want |[Want](js-apis-featureAbility.md#Want)| Yes| Information about the **Want** used for starting an ability.|
  | callback | AsyncCallback<[AbilityResult](js-apis-featureAbility.md#abilityresult)> | Yes| Callback used to return the result.|


- Example
  ```
  this.context.startAbilityForResult(
      {bundleName: "com.extreme.myapplication", abilityName: "MainAbilityDemo2"},
      (error, result) => {
          console.log("startAbilityForResult AsyncCallback is called, error.code = " + error.code)
          console.log("startAbilityForResult AsyncCallback is called, result.resultCode = " + result.resultCode)
       }
  );
  ```

## startAbilityForResult

startAbilityForResult(want: Want, options: StartOptions, callback: AsyncCallback<AbilityResult>): void;

Starts an ability. This method uses a callback to return the execution result when the ability is terminated.

**System capabilities**

SystemCapability.Ability.AbilityRuntime.Core

- Parameters
  | Name| Type| Mandatory| Description|
  | -------- | -------- | -------- | -------- |
  | want |[Want](js-apis-featureAbility.md#Want)| Yes| Information about the **Want** used for starting an ability.|
  | options | StartOptions | Yes| Parameters used for starting the ability.|
  | callback | AsyncCallback<[AbilityResult](js-apis-featureAbility.md#abilityresult)> | Yes| Callback used to return the result.|


- Example
  ```
  var options = {
    windowMode: 0,
  };
  this.context.startAbilityForResult(
      {bundleName: "com.extreme.myapplication", abilityName: "MainAbilityDemo2"}, options,
      (error, result) => {
          console.log("startAbilityForResult AsyncCallback is called, error.code = " + error.code)
          console.log("startAbilityForResult AsyncCallback is called, result.resultCode = " + result.resultCode)
       }
  );
  ```


## startAbilityForResult

startAbilityForResult(want: Want, options: StartOptions): Promise<AbilityResult>;

Starts an ability. This method uses a promise to return the execution result when the ability is terminated.

**System capabilities**

SystemCapability.Ability.AbilityRuntime.Core

- Parameters
  | Name| Type| Mandatory| Description| 
  | -------- | -------- | -------- | -------- |
  | want | [Want](js-apis-featureAbility.md#Want)| Yes| Information about the **Want** used for starting an ability.|
  | options | StartOptions | Yes| Parameters used for starting the ability.|


- Return value
  | Type| Description|
  | -------- | -------- |
  | Promise<[AbilityResult](js-apis-featureAbility.md#abilityresult)> | Promise used to return the result.|

- Example
  ```
  var options = {
    windowMode: 0,
  };
  this.context.startAbilityForResult({bundleName: "com.extreme.myapplication", abilityName: "MainAbilityDemo2"}, options).then((result) => {
      console.log("startAbilityForResult Promise.resolve is called, result.resultCode = " + result.resultCode)
  }, (error) => {
      console.log("startAbilityForResult Promise.Reject is called, error.code = " + error.code)
  })
  ```


## terminateSelf

terminateSelf(callback: AsyncCallback<void>): void;

Terminates this ability. This method uses a callback to return the result.

**System capabilities**

SystemCapability.Ability.AbilityRuntime.Core

- Parameters
  | Name| Type| Mandatory| Description| 
  | -------- | -------- | -------- | -------- |
  | callback | AsyncCallback<void> | Yes| Callback used to return the result indicating whether the method is successfully called.| 

- Example
  ```
  this.context.terminateSelf((err) => {
      console.log('terminateSelf result:' + JSON.stringfy(err));
  });
  ```


## terminateSelf

terminateSelf(): Promise<void>;

Terminates this ability. This method uses a promise to return the result.

**System capabilities**

SystemCapability.Ability.AbilityRuntime.Core

- Return value
  | Type| Description| 
  | -------- | -------- |
  | Promise<void> | Promise used to return the result indicating whether the method is successfully called.| 

- Example
  ```
  this.context.terminateSelf(want).then((data) => {
      console.log('success:' + JSON.stringfy(data));
  }).catch((error) => {
      console.log('failed:' + JSON.stringfy(error));
  });
  ```


## terminateSelfWithResult

terminateSelfWithResult(parameter: AbilityResult, callback: AsyncCallback<void>): void;

Terminates this ability. This method uses a callback to return the information to the caller of **startAbilityForResult**.

**System capabilities**

SystemCapability.Ability.AbilityRuntime.Core

- Parameters
  | Name| Type| Mandatory| Description|
  | -------- | -------- | -------- | -------- |
  | parameter | [AbilityResult](js-apis-featureAbility.md#abilityresult) | Yes| Information returned to the caller.|
  | callback | AsyncCallback<void> | Yes| Callback used to return the result.|

- Example
  ```
  this.context.terminateSelfWithResult(
     {
          want: {bundleName: "com.extreme.myapplication", abilityName: "MainAbilityDemo"},
          resultCode: 100
      }, (error) => {
          console.log("terminateSelfWithResult is called = " + error.code)
      }
  );
  ```


## terminateSelfWithResult

terminateSelfWithResult(parameter: AbilityResult): Promise<void>;

Terminates this ability. This method uses a promise to return information to the caller of **startAbilityForResult**.

**System capabilities**

SystemCapability.Ability.AbilityRuntime.Core

- Parameters
  | Name| Type| Mandatory| Description|
  | -------- | -------- | -------- | -------- |
  | parameter | [AbilityResult](js-apis-featureAbility.md#abilityresult) | Yes| Information returned to the caller.|

- Return value
  | Type| Description| 
  | -------- | -------- |
  | Promise<void> | Promise used to return the result.| 

- Example
  ```
  this.context.terminateSelfWithResult(
  {
      want: {bundleName: "com.extreme.myapplication", abilityName: "MainAbilityDemo"},
      resultCode: 100
  }).then((result) => {
      console.log("terminateSelfWithResult")
  }
  )
  ```


## startAbilityByCall

startAbilityByCall(want: Want): Promise<Caller>;

Obtains the caller interface of the specified ability, and if the specified ability is not started, starts the ability in the background.

**System capabilities**

SystemCapability.Ability.AbilityRuntime.Core

- Parameters
    | Name| Type| Mandatory| Description| 
  | -------- | -------- | -------- | -------- |
  | want | [Want](js-apis-featureAbility.md#Want)| Yes| Information about the ability to start, including the ability name, bundle name, and device ID. If the device ID is left blank or the default value is used, the local ability will be started.| 

- Return value
    | Type| Description| 
  | -------- | -------- |
  | Promise<> | Promise used to return the caller object to communicate with.| 

- Example
    
  ```
  import Ability from '@ohos.application.Ability';
  var caller;
  export default class MainAbility extends Ability {
      onWindowStageCreate(windowStage) {
          this.context.startAbilityByCall({
              bundleName: "com.example.myservice",
              abilityName: "com.example.myservice.MainAbility",
              deviceId: ""
          }).then((obj) => {
              caller = obj;
              console.log('Caller GetCaller Get ' + call);
          }).catch((e) => {
              console.log('Caller GetCaller error ' + e);
          });
      }
  }
  ```


## requestPermissionsFromUser

requestPermissionsFromUser(permissions: Array<string>, requestCallback: AsyncCallback<PermissionRequestResult>) : void;

Requests permissions from the user by displaying a pop-up window. This method uses a callback to return the result.

**System capabilities**

SystemCapability.Ability.AbilityRuntime.Core

- Parameters
    | Name| Type| Mandatory| Description| 
  | -------- | -------- | -------- | -------- |
  | permissions | Array<string> | Yes| Permissions to request.| 
  | callback | AsyncCallback<[PermissionRequestResult](js-apis-permissionrequestresult.md)> | Yes| Callback used to return the result indicating whether the method is successfully called.| 

- Example
    
  ```
  this.context.requestPermissionsFromUser(permissions,(result) => {
      console.log('requestPermissionsFromUserresult:' + JSON.stringfy(result));
  });
  ```


## requestPermissionsFromUser

requestPermissionsFromUser(permissions: Array<string>) : Promise<PermissionRequestResult>;

Requests permissions from the user by displaying a pop-up window. This method uses a promise to return the result.

**System capabilities**

SystemCapability.Ability.AbilityRuntime.Core

- Parameters
    | Name| Type| Mandatory| Description| 
  | -------- | -------- | -------- | -------- |
  | permissions | Array<string> | Yes| Permissions to request.| 

- Return value
    | Type| Description| 
  | -------- | -------- |
  | Promise<[PermissionRequestResult](js-apis-permissionrequestresult.md)> | Promise used to return the result indicating whether the method is successfully called.| 

- Example
    
  ```
  this.context.requestPermissionsFromUser(permissions).then((data) => {
      console.log('success:' + JSON.stringfy(data));
  }).catch((error) => {
      console.log('failed:' + JSON.stringfy(error));
  });
  ```


## setMissionLabel

setMissionLabel(label: string, callback:AsyncCallback<void>): void;

Sets the label of the ability displayed in the task. This method uses a callback to return the result.

**System capabilities**

SystemCapability.Ability.AbilityRuntime.Core

- Parameters
    | Name| Type| Mandatory| Description| 
  | -------- | -------- | -------- | -------- |
  | label | string | Yes| Label of the ability to set.| 
  | callback | AsyncCallback<void> | Yes| Callback used to return the result indicating whether the method is successfully called.| 

- Example
    
  ```
  this.context.setMissionLabel("test",(result) => {
      console.log('requestPermissionsFromUserresult:' + JSON.stringfy(result));
  });
  ```


## setMissionLabel

setMissionLabel(label: string): Promise<void>

Sets the label of the ability displayed in the task. This method uses a promise to return the result.

**System capabilities**

SystemCapability.Ability.AbilityRuntime.Core

- Parameters
    | Name| Type| Mandatory| Description| 
  | -------- | -------- | -------- | -------- |
  | label | string | Yes| Label of the ability to set.| 

- Return value
    | Type| Description| 
  | -------- | -------- |
  | Promise<void> | Promise used to return the result indicating whether the method is successfully called.| 

- Example
    
  ```
  this.context.setMissionLabel("test").then((data) => {
      console.log('success:' + JSON.stringfy(data));
  }).catch((error) => {
      console.log('failed:' + JSON.stringfy(error));
  });
  ```