android - 调用 onDestroy 函数时 Receiver not registered 错误

Question

当我创建扩展 BrodcastReceiver 的类并注册它时。 错误 Unable to destroy activity, Receiver not registered: null onDestroy()函数在MainActivity时调用unregisterReceiver。

onCreate():

ConnectionChangeReceiver connectionChangeReceiver = new ConnectionChangeReceiver();
IntentFilter filter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);
registerReceiver(connectionChangeReceiver, filter);

onDestroy():

@Override
protected void onDestroy() {
    Log.v("YourActivity", "onDestroy");
    unregisterReceiver(connectionChangeReceiver);
    super.onDestroy();
}

ConnectionChangeReceiver 类:

public class ConnectionChangeReceiver extends BroadcastReceiver
{
    @Override
    public void onReceive( Context context, Intent intent )
    {
        Toast.makeText(context, "CONN", Toast.LENGTH_SHORT).show();
    }
}

list :UPDATE:添加后<action android:name="android.net.conn.CONNECTIVITY_CHANGE" />

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.mamrezo.mapapp" >

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<application
    android:allowBackup="true"
    android:icon="@drawable/ic_launcher"
    android:label="@string/app_name"
    android:theme="@style/AppTheme" >


    <activity
        android:name="com.example.mamrezo.mapapp.MainActivity"
        android:label="@string/app_name"
        android:theme="@style/AppTheme" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />

            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
    <receiver android:name=".ConnectionChangeReceiver" >
        <intent-filter>
            <action android:name="android.net.conn.CONNECTIVITY_CHANGE" />
        </intent-filter>
    </receiver>

</application>

</manifest>

Answer 1

我总是在onStart 中注册 接收器并在onStop 中取消注册。由于这个答案，我知道了这一点:https://stackoverflow.com/a/24391706/1203797

如果它在您的情况下仍然不起作用，只需 wrapunregisterReceiver(connectionChangeReceiver); 一个 try-catch block 就是答案，如我发布的链接中所述以上。

或者你可以在manifest中注册它，例如:

    <receiver android:name=".ConnectionChangeReceiver" >
        <intent-filter>
            <action android:name="android.intent.action.BOOT_COMPLETED" />
        </intent-filter>
    </receiver>