如何使用C ++生成的键事件更改QML TextField文本属性

Question

I have a QML LineEdit like:

TextField
{
  id: testEdit
  text: "0"
  Keys.onPressed:
  {
    console.log("Press = " + event.key)
    console.log("Current text is " + text)
  }
  Keys.onReleased:
  {
    console.log("Release = " + event.key)
    console.log("Current text is " + text)
  }
}

I want to change its text property by simulating key events . So I have C++ object (eventHandler) exposed to QML generating key events:

void normalKeyPress(QQuickItem *receiver, QString keys)
{
  receiver->forceActiveFocus();

  QKeySequence keysSeq = QKeySequence(keys);
  for (auto idx = 0; idx < keysSeq.count(); ++idx)
  {
    auto keyCode = keysSeq[idx];
    auto keyEvent = new QKeyEvent(QEvent::KeyPress, keyCode, Qt::NoModifier);
    auto keyEventSent = QApplication::sendEvent(receiver, keyEvent);

    keyEvent = new QKeyEvent(QEvent::KeyRelease, keyCode, Qt::NoModifier);
    keyEventSent = QApplication::sendEvent(receiver, keyEvent);
  }
}

Now in QML, when I do:

testEdit.forceActiveFocus()
eventHandler.normalKeyPress(testEdit, "4")
eventHandler.normalKeyPress(testEdit, "Enter")

I get the following output:

qml: Press = 52
qml: Current text is 0
qml: Release = 52
qml: Current text is 0
qml: Press = 16777221
qml: Current text is 0
qml: Release = 16777221
qml: Current text is 0

So key events are correctly received by the QML LineEdit.

But why text property is not updated accordingly?

UPDATE #1: if I use a TextInput instead of a TextField , then it works as expected.

Answer 1

Well, looking at your code, I think the solution in adding setProperty() method to your reciever . So your code will be:

void normalKeyPress(QQuickItem *receiver, QString keys)
{
  receiver->forceActiveFocus();
  receiver->setProperty("text", keys);

  <...>
}