# Multi-device Collaboration (for System Applications Only)
## When to Use
...
...
@@ -47,18 +47,18 @@ On device A, touch the **Start** button provided by the initiator application to
### How to Develop
1. Request the **ohos.permission.DISTRIBUTED_DATASYNC** permission. For details, see [Permission Application Guide](../security/accesstoken-guidelines.md#declaring-permissions-in-the-configuration-file).
1. Request the **ohos.permission.DISTRIBUTED_DATASYNC** permission. For details, see [Applying for Permissions](../security/accesstoken-guidelines.md#stage-model).
2. Request the data synchronization permission. The sample code for displaying a dialog box to request the permission is as follows:
console.info("Succeed to request permission from user with data: "+JSON.stringify(data));
console.info("Succeed to request permission from user with data: "+JSON.stringify(data))
}).catch((error)=>{
console.info("Failed to request permission from user with error: "+JSON.stringify(error));
console.info("Failed to request permission from user with error: "+JSON.stringify(error))
})
}
```
...
...
@@ -129,18 +129,18 @@ On device A, touch the **Start** button provided by the initiator application to
### How to Develop
1. Request the **ohos.permission.DISTRIBUTED_DATASYNC** permission. For details, see [Permission Application Guide](../security/accesstoken-guidelines.md#declaring-permissions-in-the-configuration-file).
1. Request the **ohos.permission.DISTRIBUTED_DATASYNC** permission. For details, see [Applying for Permissions](../security/accesstoken-guidelines.md#stage-model).
2. Request the data synchronization permission. The sample code for displaying a dialog box to request the permission is as follows:
console.info("Succeed to request permission from user with data: "+JSON.stringify(data));
console.info("Succeed to request permission from user with data: "+JSON.stringify(data))
}).catch((error)=>{
console.info("Failed to request permission from user with error: "+JSON.stringify(error));
console.info("Failed to request permission from user with error: "+JSON.stringify(error))
})
}
```
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...
@@ -218,18 +218,30 @@ A system application can connect to a service on another device by calling [conn
### How to Develop
1. Request the **ohos.permission.DISTRIBUTED_DATASYNC** permission. For details, see [Permission Application Guide](../security/accesstoken-guidelines.md#declaring-permissions-in-the-configuration-file).
1. Configure the data synchronization permission in the **module.json5** file. The sample code is as follows:
```json
{
"module":{
"requestPermissions":[
{
"name":"ohos.permission.DISTRIBUTED_DATASYNC",
}
]
}
}
```
2. Request the data synchronization permission. The sample code for displaying a dialog box to request the permission is as follows:
console.info("Succeed to request permission from user with data: "+JSON.stringify(data));
console.info("Succeed to request permission from user with data: "+JSON.stringify(data))
}).catch((error)=>{
console.info("Failed to request permission from user with error: "+JSON.stringify(error));
console.info("Failed to request permission from user with error: "+JSON.stringify(error))
})
}
```
...
...
@@ -279,10 +291,10 @@ A system application can connect to a service on another device by calling [conn
});
},
onDisconnect(elementName){
console.info('onDisconnect callback');
console.info('onDisconnect callback')
},
onFailed(code){
console.info('onFailed callback');
console.info('onFailed callback')
}
}
// The ID returned after the connection is set up must be saved. The ID will be passed for service disconnection.
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...
@@ -305,7 +317,7 @@ A system application can connect to a service on another device by calling [conn
## Using Cross-Device Ability Call
The basic principle of cross-device ability call is the same as that of intra-device ability call. For details, see [Using Ability Call to Implement UIAbility Interaction](uiability-intra-device-interaction.md#using-ability-call-to-implement-uiability-interaction).
The basic principle of cross-device ability call is the same as that of intra-device ability call. For details, see [Using Ability Call to Implement UIAbility Interaction (for System Applications Only)](uiability-intra-device-interaction.md#using-ability-call-to-implement-uiability-interaction-for-system-applications-only).
The following describes how to implement multi-device collaboration through cross-device ability call.
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@@ -319,26 +331,38 @@ The following describes how to implement multi-device collaboration through cros
| startAbilityByCall(want: Want): Promise<Caller>; | Starts a UIAbility in the foreground or background and obtains the caller object for communicating with the UIAbility.|
| 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.|
| callWithResult(method: string, data: rpc.Sequenceable): Promise<rpc.MessageParcel> | Sends agreed sequenceable data to the callee ability and obtains the agreed sequenceable data returned by the callee ability.|
| call(method: string, data: rpc.Parcelable): Promise<void> | Sends agreed parcelable data to the callee ability.|
| callWithResult(method: string, data: rpc.Parcelable): Promise<rpc.MessageSequence> | Sends agreed parcelable data to the callee ability and obtains the agreed parcelable data returned by the callee ability.|
| release(): void | Releases the caller object.|
| on(type: "release", callback: OnReleaseCallback): void | Callback invoked when the caller object is released.|
| on(type: "release", callback: OnReleaseCallback): void | Callback invoked when the caller object is released.|
### How to Develop
1. Request the **ohos.permission.DISTRIBUTED_DATASYNC** permission. For details, see [Permission Application Guide](../security/accesstoken-guidelines.md#declaring-permissions-in-the-configuration-file).
1. Configure the data synchronization permission in the **module.json5** file. The sample code is as follows:
```json
{
"module":{
"requestPermissions":[
{
"name":"ohos.permission.DISTRIBUTED_DATASYNC",
}
]
}
}
```
2. Request the data synchronization permission. The sample code for displaying a dialog box to request the permission is as follows:
console.info("Succeed to request permission from user with data: "+JSON.stringify(data));
console.info("Succeed to request permission from user with data: "+JSON.stringify(data))
}).catch((error)=>{
console.info("Failed to request permission from user with error: "+JSON.stringify(error));
console.info("Failed to request permission from user with error: "+JSON.stringify(error))
})
}
```
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@@ -357,7 +381,6 @@ The following describes how to implement multi-device collaboration through cros
An example of the UIAbility configuration is as follows:
```json
"abilities":[{
"name": ".CalleeAbility",
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@@ -373,15 +396,15 @@ The following describes how to implement multi-device collaboration through cros
2. Import the **UIAbility** module.
```ts
importAbilityfrom'@ohos.app.ability.UIAbility';
importAbilityfrom'@ohos.app.ability.UIAbility'
```
3. Define the agreed sequenceable data.
3. Define the agreed parcelable data.
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.
```ts
exportdefaultclassMySequenceable{
export default class MyParcelable {
num: number = 0
str: string = ""
...
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@@ -390,15 +413,15 @@ The following describes how to implement multi-device collaboration through cros
this.str = string
}
marshalling(messageParcel){
messageParcel.writeInt(this.num)
messageParcel.writeString(this.str)
marshalling(messageSequence) {
messageSequence.writeInt(this.num)
messageSequence.writeString(this.str)
return true
}
unmarshalling(messageParcel){
this.num=messageParcel.readInt()
this.str=messageParcel.readString()
unmarshalling(messageSequence) {
this.num = messageSequence.readInt()
this.str = messageSequence.readString()
return true
}
}
...
...
@@ -406,7 +429,7 @@ The following describes how to implement multi-device collaboration through cros
4. Implement **Callee.on** and **Callee.off**.
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.
In the following example, the **MSG_SEND_METHOD** listener is registered in **onCreate()** of the ability and deregistered in **onDestroy()**. After receiving parcelable data, the application processes the data and returns the data result. You need to implement processing based on service requirements.
```ts
const TAG: string = '[CalleeAbility]'
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@@ -415,14 +438,14 @@ The following describes how to implement multi-device collaboration through cros
function sendMsgCallback(data) {
console.info('CalleeSortFunc called')
// Obtain the sequenceable data sent by the caller ability.
letreceivedData=newMySequenceable(0,'')
data.readSequenceable(receivedData)
// Obtain the parcelable data sent by the caller ability.
// Return the parcelable data result to the caller ability.
return new MyParcelable(receivedData.num + 1, `send ${receivedData.str} succeed`)
}
export default class CalleeAbility extends Ability {
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...
@@ -448,14 +471,13 @@ The following describes how to implement multi-device collaboration through cros
1. Import the **UIAbility** module.
```ts
importAbilityfrom'@ohos.app.ability.UIAbility';
importAbilityfrom'@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.
```ts
async onButtonGetRemoteCaller() {
var caller = undefined
...
...
@@ -469,7 +491,7 @@ The following describes how to implement multi-device collaboration through cros
if (data != null) {
caller = data
console.info('get remote caller success')
// Register the onRelease() listener of the caller ability.
// 注册caller的release监听
caller.onRelease((msg) => {
console.info(`remote caller onRelease is called ${msg}`)
})
...
...
@@ -483,38 +505,39 @@ The following describes how to implement multi-device collaboration through cros
For details about how to implement **getRemoteDeviceId()**, see [Starting UIAbility and ServiceExtensionAbility Across Devices (No Data Returned)](#starting-uiability-and-serviceextensionability-across-devices-no-data-returned).
5. Sends agreed sequenceable data to the callee ability.
1. 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.
5. Sends agreed parcelable data to the callee ability.
1. The parcelable data can be sent to the callee ability with or without a return value. The method and parcelable data must be consistent with those of the callee ability. The following example describes how to send data to the callee ability.
```ts
constMSG_SEND_METHOD:string='CallSendMsg';
constMSG_SEND_METHOD:string='CallSendMsg'
asynconButtonCall(){
try{
letmsg=newMySequenceable(1,'origin_Msg');
awaitthis.caller.call(MSG_SEND_METHOD,msg);
letmsg=newMyParcelable(1,'origin_Msg')
awaitthis.caller.call(MSG_SEND_METHOD,msg)
}catch(error){
console.info(`caller call failed with ${error}`);
console.info(`caller call failed with ${error}`)
}
}
```
2. 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**.
@@ -416,7 +416,7 @@ In summary, when a UIAbility instance of application A has been created and the
> When the [launch type of the callee UIAbility](uiability-launch-type.md) is set to **standard**, a new instance is created each time the callee UIAbility is started. In this case, the [onNewWant()](../reference/apis/js-apis-app-ability-uiAbility.md#abilityonnewwant) callback will not be invoked.
## Using Ability Call to Implement UIAbility Interaction (System Applications Only)
## Using Ability Call to Implement UIAbility Interaction (for System Applications Only)
Ability call is an extension of the UIAbility capability. It enables the UIAbility to be invoked by and communicate with external systems. The UIAbility invoked can be either started in the foreground or created and run in the background. You can use the ability call to implement data sharing between two UIAbility instances (caller ability and callee ability) through IPC.
...
...
@@ -443,9 +443,9 @@ Ability call is usually used in the following scenarios:
The following figure shows the ability call process.
**Figure 1** Ability call process
Figure 1 Ability call process
- The caller ability uses **startAbilityByCall** to obtain a caller object and uses **call()** of the caller object to send data to the callee ability.
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...
@@ -463,15 +463,15 @@ The following figure shows the ability call process.
The following table describes the main APIs used for the ability call. For details, see [AbilityContext](../reference/apis/js-apis-app-ability-uiAbility.md#caller).
**Table 2** Ability call APIs
**Table 2** Ability call APIs
| API| Description|
| -------- | -------- |
| startAbilityByCall(want: Want): Promise<Caller> | Starts a UIAbility in the foreground (through the **want** configuration) or background (default) and obtains the caller object for communication with the UIAbility. For details, see [AbilityContext](../reference/apis/js-apis-inner-application-uiAbilityContext.md#abilitycontextstartabilitybycall) or [ServiceExtensionContext](../reference/apis/js-apis-inner-application-serviceExtensionContext.md#serviceextensioncontextstartabilitybycall).|
| 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.|
| callWithResult(method: string, data: rpc.Sequenceable): Promise<rpc.MessageParcel> | Sends agreed sequenceable data to the callee ability and obtains the agreed sequenceable data returned by the callee ability.|
| call(method: string, data: rpc.Parcelable): Promise<void> | Sends agreed parcelable data to the callee ability.|
| callWithResult(method: string, data: rpc.Parcelable): Promise<rpc.MessageSequence> | Sends agreed parcelable data to the callee ability and obtains the agreed parcelable data returned by the callee ability.|
| release(): void | Releases the caller object.|
| on(type: "release", callback: OnReleaseCallback): void | Callback invoked when the caller object is released.|
...
...
@@ -487,14 +487,13 @@ The implementation of using the ability call for UIAbility interaction involves
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.
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:
An example of the ability configuration is as follows:
```json
...
...
@@ -515,13 +514,12 @@ An example of the ability configuration is as follows:
importAbilityfrom'@ohos.app.ability.UIAbility';
```
3. Define the agreed sequenceable data.
3. Define the agreed parcelable data.
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.
```ts
exportdefaultclassMySequenceable{
exportdefaultclassMyParcelable{
num:number=0
str:string=""
...
...
@@ -530,23 +528,22 @@ An example of the ability configuration is as follows:
this.str=string
}
marshalling(messageParcel){
messageParcel.writeInt(this.num)
messageParcel.writeString(this.str)
marshalling(messageSequence){
messageSequence.writeInt(this.num)
messageSequence.writeString(this.str)
returntrue
}
unmarshalling(messageParcel){
this.num=messageParcel.readInt()
this.str=messageParcel.readString()
unmarshalling(messageSequence){
this.num=messageSequence.readInt()
this.str=messageSequence.readString()
returntrue
}
}
```
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 sample code is as follows:
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 parcelable data, the application processes the data and returns the data result. You need to implement processing based on service requirements. The sample code is as follows:
```ts
...
...
@@ -556,14 +553,14 @@ An example of the ability configuration is as follows:
functionsendMsgCallback(data){
console.info('CalleeSortFunc called');
// Obtain the sequenceable data sent by the caller ability.
letreceivedData=newMySequenceable(0,'');
data.readSequenceable(receivedData);
// Obtain the parcelable data sent by the caller ability.
@@ -595,7 +592,6 @@ An example of the ability configuration is as follows:
```
2. Obtain the caller interface.
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 **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](#caller): implements sending of sequenceable data to the target ability when an ability (caller ability) invokes the target ability (callee ability).
-[Callee](#callee): implements callbacks for registration and deregistration of caller notifications.
...
...
@@ -151,7 +152,6 @@ Called when this ability is switched from the background to the foreground.
@@ -278,7 +278,7 @@ Called when the framework automatically saves the ability state in the case of a
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| reason | [AbilityConstant.StateType](js-apis-application-abilityConstant.md#abilityconstantstatetype) | Yes| Reason for triggering the callback to save the ability state.|
| reason | [AbilityConstant.StateType](js-apis-app-ability-abilityConstant.md#abilityconstantstatetype) | Yes| Reason for triggering the callback to save the ability state.|
@@ -319,8 +319,8 @@ Sends sequenceable data to the target ability.
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| method | string | Yes| Notification message string negotiated between the two abilities. The message is used to instruct the callee to register a function to receive the sequenceable data.|
| data | [rpc.Sequenceable](js-apis-rpc.md#sequenceabledeprecated) | Yes| Sequenceable data. You need to customize the data.|
| method | string | Yes| Notification message string negotiated between the two abilities. The message is used to instruct the callee to register a function to receive the parcelable data.|
| data | [rpc.Parcelable](js-apis-rpc.md#parcelable9) | Yes| Parcelable data. You need to customize the data.|
**Return value**
...
...
@@ -333,14 +333,13 @@ Sends sequenceable data to the target ability.
| ID| Error Message|
| ------- | -------------------------------- |
| 401 | If the input parameter is not valid parameter. |
For details about the error codes, see [Ability Error Codes](../errorcodes/errorcode-ability.md).
**Example**
```ts
importAbilityfrom'@ohos.app.ability.UIAbility';
classMyMessageAble{// ԶSequenceableݽṹ
classMyMessageAble{// Custom parcelable data structure.
name:''
str:''
num:1
...
...
@@ -348,15 +347,15 @@ For details about the error codes, see [Ability Error Codes](../errorcodes/error
@@ -402,21 +400,20 @@ Sends sequenceable data to the target ability and obtains the sequenceable data
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| method | string | Yes| Notification message string negotiated between the two abilities. The message is used to instruct the callee to register a function to receive the sequenceable data.|
| data | [rpc.Sequenceable](js-apis-rpc.md#sequenceabledeprecated) | Yes| Sequenceable data. You need to customize the data.|
| method | string | Yes| Notification message string negotiated between the two abilities. The message is used to instruct the callee to register a function to receive the parcelable data.|
| data | [rpc.Parcelable](js-apis-rpc.md#parcelable9) | Yes| Parcelable data. You need to customize the data.|
**Return value**
| Type| Description|
| -------- | -------- |
| Promise<[rpc.MessageParcel](js-apis-rpc.md#sequenceabledeprecated)> | Promise used to return the sequenceable data from the target ability.|
| Promise<[rpc.MessageSequence](js-apis-rpc.md#messagesequence9)> | Promise used to return the parcelable data from the target ability.|
**Error codes**
| ID| Error Message|
| ------- | -------------------------------- |
| 401 | If the input parameter is not valid parameter. |
For details about the error codes, see [Ability Error Codes](../errorcodes/errorcode-ability.md).
**Example**
...
...
@@ -431,15 +428,15 @@ For details about the error codes, see [Ability Error Codes](../errorcodes/error
@@ -581,7 +578,6 @@ Registers a callback that is invoked when the stub on the target ability is disc
| ID| Error Message|
| ------- | -------------------------------- |
| 401 | If the input parameter is not valid parameter. |
For details about the error codes, see [Ability Error Codes](../errorcodes/errorcode-ability.md).
**Example**
...
...
@@ -633,7 +629,7 @@ Deregisters a callback that is invoked when the stub on the target ability is di
| ID| Error Message|
| ------- | -------------------------------- |
| 401 | If the input parameter is not valid parameter. |
For other IDs, see [Ability Error Codes](../errorcodes/errorcode-ability.md).
For details about the error codes, see [Ability Error Codes](../errorcodes/errorcode-ability.md).
**Example**
...
...
@@ -684,7 +680,7 @@ Deregisters a callback that is invoked when the stub on the target ability is di
| ID| Error Message|
| ------- | -------------------------------- |
| 401 | If the input parameter is not valid parameter. |
For other IDs, see [Ability Error Codes](../errorcodes/errorcode-ability.md).
For details about the error codes, see [Ability Error Codes](../errorcodes/errorcode-ability.md).
**Example**
...
...
@@ -733,14 +729,13 @@ Registers a caller notification callback, which is invoked when the target abili
| Name| Type| Mandatory| Description|
| -------- | -------- | -------- | -------- |
| method | string | Yes| Notification message string negotiated between the two abilities.|
| callback | [CalleeCallback](#calleecallback) | Yes| JS notification synchronization callback of the [rpc.MessageParcel](js-apis-rpc.md#sequenceabledeprecated) type. The callback must return at least one empty [rpc.Sequenceable](js-apis-rpc.md#sequenceabledeprecated) object. Otherwise, the function execution fails.|
| callback | [CalleeCallback](#calleecallback) | Yes| JS notification synchronization callback of the [rpc.MessageSequence](js-apis-rpc.md#messagesequence9) type. The callback must return at least one empty [rpc.Parcelable](js-apis-rpc.md#parcelable9) object. Otherwise, the function execution fails.|
**Error codes**
| ID| Error Message|
| ------- | -------------------------------- |
| 401 | If the input parameter is not valid parameter. |
For details about the error codes, see [Ability Error Codes](../errorcodes/errorcode-ability.md).
**Example**
...
...
@@ -755,15 +750,15 @@ For details about the error codes, see [Ability Error Codes](../errorcodes/error
| (indata: [rpc.MessageParcel](js-apis-rpc.md#sequenceabledeprecated)) | Yes| No| [rpc.Sequenceable](js-apis-rpc.md#sequenceabledeprecated) | Prototype of the listener function registered by the callee.|
| (indata: [rpc.MessageSequence](js-apis-rpc.md#messagesequence9)) | Yes| No| [rpc.Parcelable](js-apis-rpc.md#parcelable9) | Prototype of the listener function registered by the callee.|
