Harmony 简单的跨设备迁移代码

开发步骤（简单的迁移）

01 添加权限

在config.json文件中添加权限"ohos.permission.DISTRIBUTED_DATASYNC，允许不同设备间的数据交换。

  "module": {
    "reqPermissions": [
      {
        "name": "ohos.permission.DISTRIBUTED_DATASYNC"
      }
    ],
      .....
  }

02 实现IAbilityContinuation接口

在需要实现迁移的Ability中实现IAbilityContinuation接口，同时，该Page下的所有AbilitySlice也需要实现IAbilityContinuation接口

public class MainAbility implements IAbilityContinuation {
    ......
}

public class MainAbilitySlice implements IAbilityContinuation {
    ......
}

03 在Ability中的onStart()方法中通过requestPermissionsFromUser()获取用户授权

public class MainAbility implements IAbilityContinuation {
    private void onStart(Intent intent) {
        super.onStart(intent);
        super.setMainRoute(MainAbilitySlice.class.getName());
        requestPermissionsFromUser(new String[] {"ohos.permission.DISTRIBUTED_DATASYNC"},0);
    }
}

完成以上三个步骤，一个简答的迁移基本就完成了，最后再通过调用continuation()来请求迁移即可

try {
    continuation();
}catch (Exception e) {
    e.printStackTrace();
}

04 根据需要重写IABilityContinuation接口中的方法

    @Override
    public boolean onStartContinuation() {
        System.out.println("this is onStartContinuation");
        return true;
    }

    @Override
    public boolean onSaveData(IntentParams intentParams) {
        System.out.println("this is onSavaData");
        intentParams.setParam("input",input.getText());
        return true;
    }

    @Override
    public boolean onRestoreData(IntentParams intentParams) {
        if(intentParams.getParam("input") instanceof String) {
            text = (String) intentParams.getParam("input");
            flag = true;
        }
        return true;
    }

    @Override
    public void onCompleteContinuation(int i) {
        terminate();
    }