如果有人在 Android 设备上按下后退键,我需要阻止我正在执行的应用程序退出,这样我就可以发送一个消息框来询问用户是否想离开该应用程序,我发现使用:
@Override
void MainWindow::onBackPressed()
{
...
}
我可以处理那个事件,我在我的 necessitas 项目上尝试过,但没有成功。 qtkeyevent 可以处理这个吗?或者还有其他方法吗?
我用这个来阻止它:
@Override
public boolean onKeyDown(int keyCode, KeyEvent event)
{
if ( (keyCode == KeyEvent.KEYCODE_BACK) )
{
//moveTaskToBack(true);
return true;
}
if (QtApplication.m_delegateObject != null &&
QtApplication.onKeyDown != null)
return (Boolean)
QtApplication.invokeDelegateMethod(QtApplication.onKeyDown, keyCode, event);
else
return super.onKeyDown(keyCode, event);
}
现在我需要在 Qt 上捕获事件以便发送消息
最佳答案
解决方法如下:
@Override
public boolean onKeyDown(int keyCode, KeyEvent event)
{
int newKeyCode = keyCode;
if ( (keyCode == KeyEvent.KEYCODE_BACK) )
{
newKeyCode = KeyEvent.KEYCODE_MEDIA_PREVIOUS;
}
if (QtApplication.m_delegateObject != null &&
QtApplication.onKeyDown != null)
return (Boolean)
QtApplication.invokeDelegateMethod(QtApplication.onKeyDown, newKeyCode,
event);
else
return super.onKeyDown(newKeyCode, event);
}
public boolean super_onKeyDown(int keyCode, KeyEvent event)
{
return super.onKeyDown(keyCode, event);
}
//---------------------------------------------------------------------------
@Override
public boolean onKeyMultiple(int keyCode, int repeatCount, KeyEvent
event)
{
int newKeyCode = keyCode;
if ( (keyCode == KeyEvent.KEYCODE_BACK) )
{
newKeyCode = KeyEvent.KEYCODE_MEDIA_PREVIOUS;
}
if (QtApplication.m_delegateObject != null &&
QtApplication.onKeyMultiple != null)
return (Boolean)
QtApplication.invokeDelegateMethod(QtApplication.onKeyMultiple ,newKeyCode,
repeatCount, event);
else
return super.onKeyMultiple(newKeyCode, repeatCount, event);
}
public boolean super_onKeyMultiple(int keyCode, int repeatCount,
KeyEvent event)
{
return super.onKeyMultiple(keyCode, repeatCount, event);
}
//---------------------------------------------------------------------------
@Override
public boolean onKeyUp(int keyCode, KeyEvent event)
{
int newKeyCode = keyCode;
if ( (keyCode == KeyEvent.KEYCODE_BACK) )
{
newKeyCode = KeyEvent.KEYCODE_MEDIA_PREVIOUS;
}
if (QtApplication.m_delegateObject != null &&
QtApplication.onKeyDown != null)
return (Boolean)
QtApplication.invokeDelegateMethod(QtApplication.onKeyUp, newKeyCode,
event);
else
return super.onKeyUp(newKeyCode, event);
}
public boolean super_onKeyUp(int keyCode, KeyEvent event)
{
return super.onKeyUp(keyCode, event);
}
然后在 Qt 中:
void MainWindow::keyPressEvent(QKeyEvent *k)
{
if( k->key() == Qt::Key_MediaPrevious )
{
int ret = messageBox( QMessageBox::Yes | QMessageBox::No, "¿Desea salir de la aplicación?", QMessageBox::Question);
switch(ret)
{
case QMessageBox::Yes:
this->close();
break;
case QMessageBox::No:
break;
}
}
}
感谢 Koying 在此处发布此解决方案 http://groups.google.com/group/android-qt/browse_thread/thread/676c24e94bb9a200?pli=1
关于android - 使用Qt时如何在android中阻止后退键,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/9219747/