title: QT qml Button emits Signal clicked although disabled
body: <p>I am working on a QT Quick Controls 2 application for Android and using Qt Bluetooth for communication with the device.
  By clicking a button (using the <code>onClicked()</code> signal) the app calls a function of my c++ class for the Bluetooth communication. It sends the command to the device and waits for an answer. So far it´s working well.</p>
  
  <p>Now my Problem:
  I disable the button when clicked, call the Bluetooth function, then enable the button again, to prevent multiple clicks while waiting for an answer, but however, the button emits the <code>onClicked()</code> signal while waiting although its property enabled is false.</p>
  
  <p>When I don't enable the button once the Bluetooth dialog is finished, it can only be clicked once (like expected), but I want it to be enabled again.</p>
  
  <p>Multiple emission of the signal causes relevant problems on the hardware backend.</p>
  
  <p>Any idea how to fix this? </p>
  
  <p>Button onClicked() signal:</p>
  
  <pre><code>    bEdit.onClicked: {
          bEdit.enabled = false;
          btConnect.fill("1", "30");
          bEdit.enabled = true;
  }
  </code></pre>
  
  <p>Bluetooth write and read:</p>
  
  <pre><code>unsigned int Bluetooth::fill(QString slot, QString volume)
  {
      QString output = ("CK Fill " + slot + " " + volume + "\r\n");
      QByteArray baOutput = output.toLatin1();
      static const QString serviceUuid(QStringLiteral("00001101-0000-1000-8000-00805F9B34FB"));
      socket-&gt;connectToService(QBluetoothAddress("98:d3:32:20:46:b9"), QBluetoothUuid(serviceUuid), QIODevice::ReadWrite);
      socket-&gt;write(baOutput);
      QString input = "";
      while(input == "")
      {
          input = socket-&gt;readAll();
      }
      qDebug() &lt;&lt; input;
      return 0;
  }
  </code></pre>