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BroadcastReceiverWifi またはモバイル ネットワークへの接続状態を監視する があります。これの要点は、ハンドセットが接続を確立したときにBroadcastReceiverにアクセスすることです。SQLite Database

したがって、私のonPause方法では、受信者を登録します。

networkMonitor = new CaseQueueReceiver();
IntentFilter filter = new IntentFilter(ConnectivityManager.CONNECTIVITY_ACTION);        
registerReceiver(networkMonitor, filter);

そして私のonDestory方法では、登録を解除します

unregisterReceiver(networkMonitor);

このネットワークに渡って モニター受信機

public class CaseQueueReceiver extends BroadcastReceiver {

    public boolean available;
    DatabaseHandler db;
    QueueDB queueDB; 
    HashMap<String, String> queueHashMap;

    public CaseQueueReceiver() {
        db = new DatabaseHandler(ContextHelper.context());
        queueDB = new QueueDB(ContextHelper.context()); 
        queueHashMap = new HashMap<String, String>(); 
    }

    @Override
    public void onReceive(Context context, Intent intent) {
        if (intent.getAction().equals(ConnectivityManager.CONNECTIVITY_ACTION)) {
            NetworkInfo info = intent.getParcelableExtra(ConnectivityManager.EXTRA_NETWORK_INFO);
            String typeName = info.getTypeName();
            String subtypeName = info.getSubtypeName();
            available = info.isAvailable();
            Log.i("Network Monitor", "Network Type: " + typeName 
                + ", subtype: " + subtypeName
                + ", available: " + available);

          //call a method which will get all the unsent cases from the database, and update their field of sent status
         //in order to do so, add an extra column in the database, also remember to delete the cases.    

         if(available) {

             int count = queueDB.countUnsentCases();
             Log.i("Count unsentCases: ", Integer.toString(count));
             queueDB.getUnsetCases();

            // Iterator<Entry<String, String>> it = queueHashMap.entrySet().iterator();
//           while (it.hasNext()) {
//                  Map.Entry pairs = (Map.Entry)it.next();
//                  Log.i("In the Queue: ", "PCN: " + pairs.getKey() + " Nist-File: " + pairs.getValue());
//           }

         }
        }
    }

そして、QueueDB からの私の 2 つのメソッド

public int countUnsentCases() {

        String SQLQuery = "SELECT COUNT(" + PCN + ") FROM "
                + TABLE_CASES_IN_QUEUE + ";";
        SQLiteDatabase db = this.getWritableDatabase();

        Cursor cursor = db.rawQuery(SQLQuery, null);
        cursor.moveToFirst();
        int count = cursor.getInt(0);
        cursor.close();
        db.close();

        return count;
    }

    public HashMap<String, String> getUnsetCases() {

        HashMap<String, String> queueHashMap = new HashMap<String, String>();

        SQLiteDatabase db = this.getWritableDatabase();
        String query = "SELECT * FROM " + TABLE_CASES_IN_QUEUE + ";";
        Cursor cursor = db.rawQuery(query, null);

        if (cursor.moveToFirst()) {
            do {

                Log.i("CURSOR(0)", cursor.getString(0));
                // queueHashMap.put(cursor.getString(0), cursor.getString(1));
            } while (cursor.moveToNext());
        }
        cursor.close();
        db.close();

        return queueHashMap;
    }

私が経験している問題は、onReceiveWifi をオンにするとメソッドが無限に呼び出されることです。これにより例外が発生することはありません。アプリケーションがハングアップし、ヒープのメモリが消費されます。スレッドでデータベースの読み取り/書き込みを行う必要があることを認識しています。onReceiveこのメソッドが何度も呼び出される理由を説明できる人はいますか? この問題を解決する最善の方法は何ですか?

前もって感謝します！

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public static final String CONNECTIVITY_ACTION

Added in API level 1
A change in network connectivity has occurred. A connection has either been established or lost. The NetworkInfo for the affected network is sent as an extra; it should be consulted to see what kind of connectivity event occurred.

If this is a connection that was the result of failing over from a disconnected network, then the FAILOVER_CONNECTION boolean extra is set to true.

For a loss of connectivity, if the connectivity manager is attempting to connect (or has already connected) to another network, the NetworkInfo for the new network is also passed as an extra. This lets any receivers of the broadcast know that they should not necessarily tell the user that no data traffic will be possible. Instead, the reciever should expect another broadcast soon, indicating either that the failover attempt succeeded (and so there is still overall data connectivity), or that the failover attempt failed, meaning that all connectivity has been lost.

For a disconnect event, the boolean extra EXTRA_NO_CONNECTIVITY is set to true if there are no connected networks at all.

Constant Value: "android.net.conn.CONNECTIVITY_CHANGE"
于 2012-11-24T12:58:50.450 に答える