java - 如何在 Dashclock 扩展中维护持久的 BroadcastReceiver？

Question

这是我的 Dashclock 扩展的脚手架代码。它从 GCM 接收消息并显示信息。

public class ComputerWidget extends DashClockExtension {

    private MessageReceiver objMessageReceiver;
    private class MessageReceiver extends BroadcastReceiver {    
        @Override
        public void onReceive(Context ctxContext, Intent ittIntent) {    
            GoogleCloudMessaging gcm = GoogleCloudMessaging.getInstance(ctxContext);
            String strType = gcm.getMessageType(ittIntent);    
            if (GoogleCloudMessaging.MESSAGE_TYPE_MESSAGE.equals(strType)) {    
                showInformation(ittIntent.getExtras());    
            }    
        }    
    }

    @Override
    protected void onInitialize(boolean booReconnect) {    
        super.onInitialize(booReconnect);    
        if (objMessageReceiver != null) {    
            try {    
                unregisterReceiver(objMessageReceiver);    
            } catch (Exception e) {
                e.printStackTrace();
            }    
        }

        IntentFilter intentFilter = new IntentFilter("com.google.android.c2dm.intent.RECEIVE");
        intentFilter.addCategory("com.something.something");    
        objMessageReceiver = new MessageReceiver();
        registerReceiver(objMessageReceiver, intentFilter);
    }

    public void onCreate() {    
        super.onCreate();    
    }

    protected void showInformation(Bundle bndBundle) {    
        final ExtensionData edtInformation = new ExtensionData();
        setUpdateWhenScreenOn(true);    
        try {    
            if (bndBundle.getString("event").equalsIgnoreCase("logon")) {    
                edtInformation.visible(true);
                    edtInformation.expandedTitle(bndBundle.getString("machine"));
                edtInformation.expandedBody(getString(R.string.logon, bndBundle.getString("username")));
                    }    
        } catch (Exception e) {
            edtInformation.visible(false);
        }    
        edtInformation.icon(R.drawable.ic_dashclock);
        publishUpdate(edtInformation);
    }

    public void onDestroy() {    
        super.onDestroy();    
        if (objMessageReceiver != null) {    
            try {    
                unregisterReceiver(objMessageReceiver);    
            } catch (Exception e) {
                e.printStackTrace();
            }    
        }    
    }

    @Override
    protected void onUpdateData(int arg0) {    
        setUpdateWhenScreenOn(true);
        System.out.println("Update");    
    }

}

如您所见，我在初始化扩展时注册我的 GCM BroadcastReceiver，在销毁扩展时注销它。

只要接收器已初始化，这段代码就可以正常工作，但 Dashclock 在一段时间不活动后会破坏扩展，因此我无法接收任何 GCM 消息。

如何让 BroadcastReceiver 保持 Activity 状态以便接收 GCM 消息？有没有办法以编程方式而不是通过 list 文件来完成此操作？

在我最后一个关于 BroadcastRecievers 的问题之后，我想到了这个解决方案 — How do I publish an update to Dashclock when my application receives an Intent?

Answer 1

How can I keep the BroadcastReceiver alive so that I can receive GCM messages?

按照 GCM 示例向您展示的方式在 list 中注册它。

Is there a way to accomplish this programatically and not through the manifest file?

不可以，但您可以通过 PackageManager 和 setComponentEnabledSetting() 启用和禁用 list 注册接收器。