@@ -25,7 +25,7 @@ Carry out the following operations to develop the widget provider based on the [
1. Implement lifecycle callbacks by using the **LifecycleForm** APIs.
2. Create a **FormBindingData** instance.
3. Update a widget by using the **FormProvider** APIs.
4. Develop the widget UI pages.
4. Develop the widget UI page.
## Available APIs
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@@ -231,7 +231,7 @@ You should override **onDestroy** to implement widget data deletion.
}
```
For details about how to implement persistent data storage, see [Lightweight Data Store Development](../database/database-preference-guidelines.md).
For details about how to implement persistent data storage, see [Data Persistence by User Preferences](../database/data-persistence-by-preferences.md).
The **Want** object passed in by the widget host to the widget provider contains a flag that specifies whether the requested widget is normal or temporary.
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@@ -402,3 +402,5 @@ The code snippet is as follows:
@@ -6,7 +6,7 @@ Ability continuation is to continue the current mission of an application, inclu
## Available APIs
The following table lists the APIs used for ability continuation. For details about the APIs, see [Ability](../reference/apis/js-apis-application-ability.md).
The following table lists the APIs used for ability continuation. For details about the APIs, see [UIAbility](../reference/apis/js-apis-app-ability-uiAbility.md).
**Table 1** Ability continuation APIs
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@@ -48,12 +48,9 @@ The code snippets provided below are all from [Sample](https://gitee.com/openhar
}
```
- Configure the application startup type.
If **launchType** is set to **standard** in the **module.json5** file, the application is of the multi-instance launch type. During ability continuation, regardless of whether the application is already open, the target starts the application and restores the UI page. If **launchType** is set to **singleton**, the application is of the singleton launch type. If the application is already open, the target clears the existing page stack and restores the UI page. For more information, see "Launch Type" in [Ability Development](./stage-ability.md).
If **launchType** is set to **multiton** in the **module.json5** file, the application is of the multi-instance launch type. During ability continuation, regardless of whether the application is already open, the target starts the application and restores the UI page. If **launchType** is set to **singleton**, the application is of the singleton launch type. If the application is already open, the target clears the existing page stack and restores the UI page. For more information, see "Launch Type" in [Ability Development](./stage-ability.md).
Configure a multi-instance application as follows:
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@@ -62,7 +59,7 @@ The code snippets provided below are all from [Sample](https://gitee.com/openhar
"module":{
"abilities":[
{
"launchType": "standard"
"launchType":"multiton"
}
]
}
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@@ -83,8 +80,6 @@ The code snippets provided below are all from [Sample](https://gitee.com/openhar
}
```
- Apply for the distributed permissions.
Declare the **DISTRIBUTED_DATASYNC** permission in the **module.json5** file for the application.
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@@ -96,8 +91,6 @@ The code snippets provided below are all from [Sample](https://gitee.com/openhar
},
```
This permission must be granted by the user in a dialog box when the application is started for the first time. To enable the application to display a dialog box to ask for the permission, add the following code to **onWindowStageCreate** of the **Ability** class:
```javascript
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@@ -139,7 +132,6 @@ The code snippets provided below are all from [Sample](https://gitee.com/openhar
2. Implement the **onContinue()** API.
The **onContinue()** API is called by the initiator to save the UI component state variables and memory data and prepare for continuation. After the application completes the continuation preparation, the system must return either **OnContinueResult.AGREE(0)** to accept the continuation request or an error code to reject the request. If this API is not implemented, the system rejects the continuation request by default.
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@@ -155,7 +147,7 @@ The code snippets provided below are all from [Sample](https://gitee.com/openhar
You can obtain the target device ID (identified by the key **targetDevice**) and the version number (identified by the key **version**) of the application installed on the target device from the **wantParam** parameter of this API. The version number can be used for compatibility check. If the current application version is incompatible with that on the target device, **OnContinueResult.MISMATCH** can be returned to reject the continuation request.
Example
Example:
```javascript
onContinue(wantParam:{[key:string]:any}){
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@@ -168,8 +160,6 @@ The code snippets provided below are all from [Sample](https://gitee.com/openhar
}
```
3. Implement the continuation logic in the **onCreate()** or **onNewWant()** API.
The **onCreate()** API is called by the target. When the ability is started on the target device, this API is called to instruct the application to synchronize the memory data and UI component state, and triggers page restoration after the synchronization is complete. If the continuation logic is not implemented, the ability will be started in common startup mode and the page cannot be restored.
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@@ -178,11 +168,9 @@ The code snippets provided below are all from [Sample](https://gitee.com/openhar
After data restore is complete, call **restoreWindowStage** to trigger page restoration.
You can also use **want.parameters.version** in the **want** parameter to obtain the application version number of the initiator.
Example
Example:
```javascript
importUIAbilityfrom'@ohos.app.ability.UIAbility';
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@@ -211,7 +199,7 @@ For a singleton ability, use **onNewWant()** to achieve the same implementation.
Use distributed objects.
Distributed objects allow cross-device data synchronization like local variables. For two devices that form a Super Device, when data in the distributed data object of an application is added, deleted, or modified on a device, the data for the same application is also updated on the other device. Both devices can listen for the data changes and online and offline states of the other. For details, see [Distributed Data Object Development](../database/database-distributedobject-guidelines.md).
Distributed objects allow cross-device data synchronization like local variables. For two devices that form a Super Device, when data in the distributed data object of an application is added, deleted, or modified on a device, the data for the same application is also updated on the other device. Both devices can listen for the data changes and online and offline states of the other. For details, see [Sharing Distributed Data Objects](../database/data-sync-of-distributed-data-object.md).
In the ability continuation scenario, the distributed data object is used to synchronize the memory data from the local device to the target device.
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@@ -249,8 +237,6 @@ In the ability continuation scenario, the distributed data object is used to syn
});
```
- The target device obtains the session ID from **onCreate()**, creates a distributed object, and associates the distributed object with the session ID. In this way, the distributed object can be synchronized. Before calling **restoreWindowStage**, ensure that all distributed objects required for continuation have been associated.
```javascript
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@@ -283,8 +269,6 @@ In the ability continuation scenario, the distributed data object is used to syn
}
```
### More Information
1. Timeout
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@@ -294,15 +278,13 @@ In the ability continuation scenario, the distributed data object is used to syn
2. By default, the system supports page stack information migration, which means that the page stack of the initiator will be automatically migrated to the target device. No adaptation is required.
### Restrictions
1. The continuation must be performed between the same ability, which means the same bundle name, module name, and ability name. For details, see [Application Package Structure Configuration File](../quick-start/module-configuration-file.md).
2. Currently, the application can only implement the continuation capability. The continuation action must be initiated by the system.
### Best Practice
For better user experience, you are advised to use the **wantParam** parameter to transmit data smaller than 100 KB and use distributed objects to transmit data larger than 100 KB.
@@ -12,8 +12,8 @@ An ability can be launched in the **standard**, **singleton**, or **specified**
| Launch Type | Description |Action |
| ----------- | ------- |---------------- |
| standard | Standard mode | A new instance is started each time an ability starts.|
| singleton | Singleton mode | The ability has only one instance in the system. If an instance already exists when an ability is started, that instance is reused.|
| multiton | Multi-instance mode| A new instance is started each time an ability starts.|
| singleton | Singleton mode | Default type. The ability has only one instance in the system. If an instance already exists when an ability is started, that instance is reused.|
| specified | Instance-specific| The internal service of an ability determines whether to create multiple instances during running.|
By default, the singleton mode is used. The following is an example of the **module.json5** file:
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@@ -39,7 +39,7 @@ The table below describes the APIs provided by the **AbilityStage** class, which
|onAcceptWant(want: Want): string|Called when a specified ability is started.|
|onConfigurationUpdated(config: Configuration): void|Called when the global configuration is updated.|
The table below describes the APIs provided by the **Ability** class. For details about the APIs, see [Ability](../reference/apis/js-apis-application-ability.md).
The table below describes the APIs provided by the **Ability** class. For details about the APIs, see [UIAbility](../reference/apis/js-apis-app-ability-uiAbility.md).
The **Ability** class has the **context** attribute, which belongs to the **AbilityContext** class. The **AbilityContext** class has the **abilityInfo**, **currentHapModuleInfo**, and other attributes as well as the APIs used for starting abilities. For details, see [AbilityContext](../reference/apis/js-apis-ability-context.md).
The **Ability** class has the **context** attribute, which belongs to the **AbilityContext** class. The **AbilityContext** class has the **abilityInfo**, **currentHapModuleInfo**, and other attributes as well as the APIs used for starting abilities. For details, see [AbilityContext](../reference/apis/js-apis-inner-application-uiAbilityContext.md).
**Table 3** AbilityContext APIs
|API|Description|
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@@ -207,7 +207,7 @@ The **Ability** class has the **context** attribute, which belongs to the **Abil
An application can obtain the context of an **Ability** instance through **this.context** and then use the **startAbility** API in the **AbilityContext** class to start the ability. The ability can be started by specifying **Want**, **StartOptions**, and **accountId**, and the operation result can be returned using a callback or **Promise** instance. The sample code is as follows:
@@ -31,12 +31,12 @@ The ability call process is as follows:
> Currently, only system applications can use the ability call.
## Available APIs
The table below describes the ability call APIs. For details, see [Ability](../reference/apis/js-apis-application-ability.md#caller).
The table below describes the ability call APIs. For details, see [UIAbility](../reference/apis/js-apis-app-ability-uiAbility.md#caller).
**Table 2** Ability call APIs
|API|Description|
|:------|:------|
|startAbilityByCall(want: Want): Promise\<Caller>|Starts an ability in the foreground (through the **want** configuration) or background (default) and obtains the **Caller** object for communication with the ability. For details, see [AbilityContext](../reference/apis/js-apis-ability-context.md#abilitycontextstartabilitybycall) or **ServiceExtensionContext**.|
|startAbilityByCall(want: Want): Promise\<Caller>|Starts an ability in the foreground (through the **want** configuration) or background (default) and obtains the **Caller** object for communication with the ability. For details, see [AbilityContext](../reference/apis/js-apis-inner-application-uiAbilityContext.md#uiabilitycontextstartabilitybycall) or **ServiceExtensionContext**.|
|on(method: string, callback: CalleeCallBack): void|Callback invoked when the callee ability registers a method.|
|off(method: string): void|Callback invoked when the callee ability deregisters a method.|
|call(method: string, data: rpc.Sequenceable): Promise\<void>|Sends agreed sequenceable data to the callee ability.|
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@@ -47,40 +47,45 @@ The table below describes the ability call APIs. For details, see [Ability](../r
## How to Develop
The procedure for developing the ability call is as follows:
1. Create a callee ability.
2. Access the callee ability.
### Creating a Callee Ability
For the callee ability, implement the callback to receive data and the methods to marshal and unmarshal data. When data needs to be received, use **on()** to register a listener. When data does not need to be received, use **off()** to deregister the listener.
**1. Configure the ability launch type.**
1.**Configure the ability launch type.**
Set **launchType** of the callee ability to **singleton** in the **module.json5** file.
|JSON Field|Description|
|:------|:------|
|"launchType"|Ability launch type. Set this parameter to **singleton**.|
|JSON Field|Description|
|:------|:------|
|"launchType"|Ability launch type. Set this parameter to **singleton**.|
An example of the ability configuration is as follows:
```json
"abilities":[{
An example of the ability configuration is as follows:
The data formats sent and received by the caller and callee abilities must be consistent. In the following example, the data formats are number and string. The code snippet is as follows:
```ts
exportdefaultclassMySequenceable{
```ts
exportdefaultclassMySequenceable{
num:number=0
str:string=""
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@@ -100,16 +105,18 @@ export default class MySequenceable {
this.str=messageParcel.readString()
returntrue
}
}
```
**4. Implement Callee.on and Callee.off.**
}
```
4.**Implement Callee.on and Callee.off.**
The time to register a listener for the callee ability depends on your application. The data sent and received before the listener is registered and that after the listener is deregistered are not processed. In the following example, the **MSG_SEND_METHOD** listener is registered in **onCreate** of the ability and deregistered in **onDestroy**. After receiving sequenceable data, the application processes the data and returns the data result. You need to implement processing based on service requirements. The code snippet is as follows:
```ts
constTAG:string='[CalleeAbility]'
constMSG_SEND_METHOD:string='CallSendMsg'
functionsendMsgCallback(data){
```ts
constTAG:string='[CalleeAbility]'
constMSG_SEND_METHOD:string='CallSendMsg'
functionsendMsgCallback(data){
console.log('CalleeSortFunc called')
// Obtain the sequenceable data sent by the caller ability.
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@@ -120,9 +127,9 @@ function sendMsgCallback(data) {
// Process the data.
// Return the sequenceable data result to the caller ability.
console.error(TAG,`${MSG_SEND_METHOD} unregister failed with error ${JSON.stringify(error)}`)
}
}
}
```
}
```
### Accessing the Callee Ability
**1. Import the Ability module.**
```ts
importAbilityfrom'@ohos.app.ability.UIAbility'
```
**2. Obtain the Caller object.**
1.**Import the Ability module.**
```ts
importUIAbilityfrom'@ohos.app.ability.UIAbility';
```
2.**Obtain the Caller object.**
The **context** attribute of the ability implements **startAbilityByCall** to obtain the **Caller** object for communication. The following example uses **this.context** to obtain the **context** attribute of the ability, uses **startAbilityByCall** to start the callee ability, obtain the **Caller** object, and register the **onRelease** listener of the caller ability. You need to implement processing based on service requirements. The code snippet is as follows:
```ts
// Register the onRelease listener of the caller ability.
privateregOnRelease(caller){
```ts
// Register the onRelease listener of the caller ability.
console.error(`get remote caller failed with ${error}`)
})
}
```
}
```
Obtain the ID of the peer device from **DeviceManager**. Note that the **getTrustedDeviceListSync** API is open only to system applications. The code snippet is as follows:
console.log("Failed to request permission from user with error: "+JSON.stringify(error))
})
}
```
**3. Send agreed sequenceable data.**
}
```
3.**Send agreed sequenceable data.**
The sequenceable data can be sent to the callee ability with or without a return value. The method and sequenceable data must be consistent with those of the callee ability. The following example describes how to send data to the callee ability. The code snippet is as follows:
```ts
constMSG_SEND_METHOD:string='CallSendMsg'
asynconButtonCall(){
```ts
constMSG_SEND_METHOD:string='CallSendMsg'
asynconButtonCall(){
try{
letmsg=newMySequenceable(1,'origin_Msg')
awaitthis.caller.call(MSG_SEND_METHOD,msg)
}catch(error){
console.log(`caller call failed with ${error}`)
}
}
```
}
```
In the following, **CallWithResult** is used to send data **originMsg** to the callee ability and assign the data processed by the **CallSendMsg** method to **backMsg**. The code snippet is as follows:
| name | Name of the Extension ability. This field must be specified. | String | No |
| srcEntrance | Path of the Extension ability lifecycle code. This field must be specified.| String | No |
| srcEntry | Path of the Extension ability lifecycle code. This field must be specified.| String | No |
| description | Description of the Extension ability. The value can be a string or a resource index to descriptions in multiple languages.| String | Yes (initial value: left empty)|
| icon | Index of the Extension ability icon file. | String | Yes (initial value: left empty)|
| label | Descriptive information about the Extension ability presented externally. The value can be a string or a resource index to the description.| String | Yes (initial value: left empty)|
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@@ -150,7 +150,7 @@ To create a widget in the stage model, you need to implement lifecycle callbacks
@@ -242,7 +242,7 @@ You should override **onDestroy** to implement widget data deletion.
}
```
For details about how to implement persistent data storage, see [Lightweight Data Store Development](../database/database-preference-guidelines.md).
For details about how to implement persistent data storage, see [Application Data Persistence Overview](../database/app-data-persistence-overview.md).
The **Want** object passed in by the widget host to the widget provider contains a flag that specifies whether the requested widget is normal or temporary.
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@@ -366,7 +366,7 @@ You can set router and message events for components on a widget. The router eve
1. Set the **onclick** field in the HML file to **routerEvent** or **messageEvent**, depending on the **actions** settings in the JSON file.
2. Set the router event.
- **action**: **"router"**, which indicates a router event.
- **abilityName**: target ability name, for example, **EntryAbility**, which is the default UIAbility name in DevEco Studio for the stage model.
- **abilityName**: target ability name, for example, **EntryAbility**, which is the default main ability name in DevEco Studio for the stage model.
- **params**: custom parameters of the target ability. Set them as required. The value can be obtained from **parameters** in **want** used for starting the target ability. For example, in the lifecycle function **onCreate** of the EntryAbility in the stage model, you can obtain **want** and its **parameters** field.
3. Set the message event.
- **action**: **"message"**, which indicates a message event.
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@@ -413,3 +413,5 @@ The code snippet is as follows:
