Question

我正在编写一个使用Firebase实施通知的应用程序。在我的MainActivity中，我有一个带有某些URL的WebView，但事实是，当用户单击通知时，我想在WebView中使用不同的URL打开MainActiviy。我已经阅读了很多书，并且向意图（当单击通知时将打开MainActivity）添加了一个捆绑包，该捆绑包包含所需的网址。但是，当我单击通知时，MainActivity重新启动，这意味着它不会转到onNewIntent，而是运行在onCreate上。这就是我的实现方式：

private void sendNotification(String messageTitle, String messageBody, String url){

    Intent intent = new Intent(this, MainActivity.class);
    intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);

    //This adds the url to the intent
    if(!url.equals("")){
        Bundle bundle = new Bundle();
        bundle.putString("url", url);
        intent.putExtras(bundle);
    }

    PendingIntent pendingIntent = PendingIntent.getActivity(this, 0,intent, PendingIntent.FLAG_ONE_SHOT);

    String channelId = getString(R.string.default_notification_channel_id);

    NotificationCompat.Builder notificationBuilder = new NotificationCompat
            .Builder(this, channelId)
            .setContentTitle(messageTitle)
            .setContentText(messageBody)
            .setPriority(NotificationCompat.PRIORITY_DEFAULT)
            .setAutoCancel(true)
            .setSmallIcon(R.drawable.ic_launcher_background)
            .setContentIntent(pendingIntent);

    NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);

    if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.O){
        NotificationChannel channel = new NotificationChannel(channelId,
                "Notification channel",
                NotificationManager.IMPORTANCE_DEFAULT);
        notificationManager.createNotificationChannel(channel);
    }

    notificationManager.notify(0, notificationBuilder.build());

}

onNewIntent我有这个：

Bundle bundle = intent.getExtras();
        if (bundle != null) {
            String url = bundle.getString("url");
            mWebView.loadUrl(url);
        }

但是当单击通知时，活动仅重新启动，因此它不会在onNewIntent上运行，并且日志显示此错误：

02-08 12:51:12.140 19056-19056/com.example.android.app E/ActivityThread: Activity com.example.android.app.MainActivity has leaked IntentReceiver com.example.android.app.MainActivity$1@d7818db that was originally registered here. Are you missing a call to unregisterReceiver()?
android.app.IntentReceiverLeaked: Activity com.example.android.app.MainActivity has leaked IntentReceiver com.example.android.app.MainActivity$1@d7818db that was originally registered here. Are you missing a call to unregisterReceiver()?
    at android.app.LoadedApk$ReceiverDispatcher.<init>(LoadedApk.java:999)
    at android.app.LoadedApk.getReceiverDispatcher(LoadedApk.java:795)
    at android.app.ContextImpl.registerReceiverInternal(ContextImpl.java:1329)
    at android.app.ContextImpl.registerReceiver(ContextImpl.java:1309)
    at android.app.ContextImpl.registerReceiver(ContextImpl.java:1303)
    at android.content.ContextWrapper.registerReceiver(ContextWrapper.java:554)
    at com.example.android.app.MainActivity.onCreate(MainActivity.java:264)
    at android.app.Activity.performCreate(Activity.java:6367)
    at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1110)
    at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2404)
    at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2511)
    at android.app.ActivityThread.access$900(ActivityThread.java:165)
    at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1375)
    at android.os.Handler.dispatchMessage(Handler.java:102)
    at android.os.Looper.loop(Looper.java:150)
    at android.app.ActivityThread.main(ActivityThread.java:5621)
    at java.lang.reflect.Method.invoke(Native Method)
    at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:794)
    at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:684)

我读过一个关于stackoverflow的类似问题，就是要注销BroadCastReceiver来修复此错误，但是我对如何做到这一点有些迷失。

我尝试将sendNotification的意图更改为

Intent intent = new Intent("android.intent.action.MAIN");

但是在这种情况下，当用户单击通知时，它什么也没做。

有人知道如何解决它，以便在用户单击时加载URL吗？预先谢谢你

Answer 1

在Android docs中声明：

如果它已将其启动模式声明为“多个”（默认），并且您未将FLAG_ACTIVITY_SINGLE_TOP设置为相同的意图，则它将完成并重新创建；对于所有其他启动模式，或者如果设置了FLAG_ACTIVITY_SINGLE_TOP，则此Intent将被传递到当前实例的onNewIntent（）。

因此，看起来在创建新的Intent时设置FLAG_ACTIVITY_SINGLE_TOP标志应该解决并运行onNewIntent（）方法，而不是重新创建应用程序。

Answer 2

创建这样的方法

private PendingIntent retrievePlaybackAction(final String action) {
    Intent intent = new Intent(action);
    return PendingIntent.getBroadcast(this, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
}

现在添加您的意图

builder.setContentIntent(retrievePlaybackAction("OPEN_MAIN")); //change action text as you want

创建一个我想您已经创建的简单类NotificationReceiver，现在从您要发送通知的位置创建该类的对象

private NotificationReceiver notificationReceiver;

在onCreate()中注册您的接收者

notificationReceiver = new NotificationReceiver();

IntentFilter intentFilterNextClick = new IntentFilter("OPEN_MAIN");

registerReceiver(notificationReceiver, intentFilterNextClick); 
//can create exception, better to surround with try catch

在onDestroy()中取消注册接收者

unregisterReceiver(notificationReceiver); 
//can create exception, better to surround with try catch

要打开或执行某些操作，请将其添加到接收器中

@Override
public void onReceive(Context context, Intent intent) {
    Log.e(TAG, "onReceive: received " + intent.getAction());

    String action = intent.getAction();

    //no need to create switch you can also use if
    switch (action) {
        case "OPEN_MAIN":
            openMain();
            break;
    }

}

//here is openMain();
private void openMain(Context context) {
    Intent openMainIntent = new Intent(context, MainActivity.class);
    openMainIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK); //this flag is important
    context.startActivity(openMainIntent);
}

如果应用程序最小化或关闭，这也将起作用

希望这会有所帮助！

请询问是否需要更多帮助！

Firebase-用户单击通知时，活动将重新启动

2 个答案: