QML: Move a frameless window by dragging - qml

Question

I have a frameless QQuickWindow, and I want to move it with the mouse by dragging. Before trying in my big application, I have created a simple test application to try what I found here, using cursor position from C++ class to avoid problems from QML:
http://www.tickanswer.com/solved/5390888353/dragging-frameless-window-jiggles-in-qml
But I failed with the code below. When I press over the red RECT and move the mouse, my yellow rect (root RECT) moves, but only inside the original size it had (in this case, 500x500)... What am I doing wrong?
Thanks in advance
In my main.cpp:
int main(int argc, char *argv[])
{
QtQuickControlsApplication a(argc, argv);
QQuickView* pView = new QQuickView();
CursorPosProvider mousePosProvider;
pView->rootContext()->setContextProperty("mousePosition", &mousePosProvider);
pView->setSource(QUrl("qrc:/Test.qml"));
pView->setFlags(Qt::FramelessWindowHint);
pView->show();
return a.exec();
}
Test.qml:
import QtQuick 2.0
Rectangle {
id: myWindow
width: 500; height: 500
color: "yellow"
Rectangle {
anchors.centerIn: parent
width: 200; height: 200
color: "red"
MouseArea {
id: titleBarMouseRegion
property var clickPos
anchors.fill: parent
onPressed: clickPos = { x: mousePosition.cursorPos().x, y: mousePosition.cursorPos().y }
onPositionChanged: {
myWindow.x = mousePosition.cursorPos().x - clickPos.x
myWindow.y = mousePosition.cursorPos().y - clickPos.y
}
}
}
}
cursorprovider.h:
#ifndef CURSORPOSPROVIDER_H
#define CURSORPOSPROVIDER_H
#include <QObject>
#include <QPointF>
#include <QCursor>
class CursorPosProvider : public QObject
{
Q_OBJECT
public:
explicit CursorPosProvider(QObject *parent = nullptr) : QObject(parent)
{
}
virtual ~CursorPosProvider() = default;
Q_INVOKABLE QPointF cursorPos()
{
return QCursor::pos();
}
};
#endif // CURSORPOSPROVIDER_H

Answer 1

I wrote this example and I see no jiggle (running on Linux)
ApplicationWindow {
id: iWindow
visible: true
title: "My title"
color: "gray"
width: 500
height: 500
MouseArea{
id: iMouseArea
property int prevX: 0
property int prevY: 0
anchors.fill: parent
onPressed: {prevX=mouse.x; prevY=mouse.y}
onPositionChanged:{
var deltaX = mouse.x - prevX;
iWindow.x += deltaX;
prevX = mouse.x - deltaX;
var deltaY = mouse.y - prevY
iWindow.y += deltaY;
prevY = mouse.y - deltaY;
}
}
}

Answer 2

I have changed the structure, I have used a QQuickWidget with a QML inside, and now I have what I wanted. Here is my code in case anyone needs something similar
main.cpp
...
MovableWidget *view = new MovableWidget;
view->setSource(QUrl("qrc:/Test.qml"));
view->setWindowFlags(Qt::FramelessWindowHint);
view->show();
...
Test.qml
import QtQuick 2.0
Rectangle {
id: myWindow
width: 500; height: 500
color: "yellow"
Rectangle {
anchors.centerIn: parent
width: 200; height: 200
color: "red"
}
}
MovableWidget.cpp
#include "movableWidget.h"
#include <QMouseEvent>
// ****************************************************************************
MovableWidget::MovableWidget(QWidget *parent)
: QQuickWidget(parent),
m_previousPos(0,0)
{
installEventFilter(this);
}
// ****************************************************************************
bool MovableWidget::eventFilter(QObject *obj, QEvent *event)
{
if (event->type() == QEvent::MouseButtonPress)
{
m_previousPos = QCursor:os();
}
else if (event->type() == QEvent::MouseMove)
{
QMouseEvent *mouseEvent = static_cast<QMouseEvent*>(event);
if(mouseEvent->buttons() == Qt::LeftButton)
{
QPoint offset = m_previousPos - QCursor:os();
m_previousPos = QCursor:os();
move(pos() - offset);
}
}
return false;
}