Custom QQuickItem in iOS not working

Hi all,

I’m going insane with a strange behaviour in iOS. I create a custom QQuickItem based on the MaskedMouseArea from the examples.

It works perfectly with Android and Desktop. But when I click on my component in iOS I get only the message:

“stale focus object QQuickloader…” and nothing happens. I can see from the logs that the component constructor in c++ was called and I get no other

message that something is wrong. But after the stale message no mouse event is triggered.


#ifndef MASKEDMOUSEAREA_H
#define MASKEDMOUSEAREA_H

#include <QImage>
#include <QQuickItem>
#include <QQmlEngine>

class MaskedMouseArea : public QQuickItem
{
    Q_OBJECT
    Q_PROPERTY(bool pressed READ isPressed NOTIFY pressedChanged)
    Q_PROPERTY(bool containsMouse READ containsMouse NOTIFY containsMouseChanged)
    Q_PROPERTY(QUrl maskSource READ maskSource WRITE setMaskSource NOTIFY maskSourceChanged)
    Q_PROPERTY(qreal alphaThreshold READ alphaThreshold WRITE setAlphaThreshold NOTIFY alphaThresholdChanged)

public:
    MaskedMouseArea(QQuickItem *parent = 0);

    Q_INVOKABLE void scaleToSized(int width, int height);
    bool contains(const QPointF &point) const;

    bool isPressed() const { return m_pressed; }
    bool containsMouse() const { return m_containsMouse; }

    QUrl maskSource() const { return m_maskSource; }
    void setMaskSource(const QUrl &source);

    qreal alphaThreshold() const { return m_alphaThreshold; }
    void setAlphaThreshold(qreal threshold);

signals:
    void pressed();
    void released();
    void clicked();
    void canceled();
    void pressedChanged();
    void maskSourceChanged();
    void containsMouseChanged();
    void alphaThresholdChanged();

protected:
    void setPressed(bool pressed);
    void setContainsMouse(bool containsMouse);
    void mousePressEvent(QMouseEvent *event);
    void mouseReleaseEvent(QMouseEvent *event);
    void hoverEnterEvent(QHoverEvent *event);
    void hoverLeaveEvent(QHoverEvent *event);
    void mouseUngrabEvent();

private:
    bool m_pressed;
    QUrl m_maskSource;
    QImage m_maskImage;
    QPointF m_pressPoint;
    qreal m_alphaThreshold;
    bool m_containsMouse;
};

#endif

#include "maskedmousearea.h"

#include <QStyleHints>
#include <QGuiApplication>
#include <qqmlfile.h>
#include <QDebug>

MaskedMouseArea::MaskedMouseArea(QQuickItem *parent)
    : QQuickItem(parent),
      m_pressed(false),
      m_alphaThreshold(0.0),
      m_containsMouse(false)
{
    setAcceptHoverEvents(true);
    setAcceptedMouseButtons(Qt::LeftButton);
}

void MaskedMouseArea::setPressed(bool pressed)
{
    if (m_pressed != pressed) {
        m_pressed = pressed;
        emit pressedChanged();
    }
}

void MaskedMouseArea::setContainsMouse(bool containsMouse)
{
    if (m_containsMouse != containsMouse) {
        m_containsMouse = containsMouse;
        emit containsMouseChanged();
    }
}
void MaskedMouseArea::scaleToSized(int width, int height){
    m_maskImage = m_maskImage.scaledToWidth(width);
  //  m_maskImage = m_maskImage.scaledToHeight(height);
    qDebug() << "target Size: " << m_maskImage.width();
}

void MaskedMouseArea::setMaskSource(const QUrl &source)
{
    if (m_maskSource != source) {
        m_maskSource = source;
        m_maskImage = QImage(QQmlFile::urlToLocalFileOrQrc(source));
        qDebug() << "target Width: " << width();
        emit maskSourceChanged();
    }
}

void MaskedMouseArea::setAlphaThreshold(qreal threshold)
{
    if (m_alphaThreshold != threshold) {
        m_alphaThreshold = threshold;
        emit alphaThresholdChanged();
    }
}

bool MaskedMouseArea::contains(const QPointF &point) const
{
    if (!QQuickItem::contains(point) || m_maskImage.isNull())
        return false;

    QPoint p = point.toPoint();

//    if (p.x() < 0 || p.x() >= m_maskImage.width() ||
//        p.y() < 0 || p.y() >= m_maskImage.height()){
//        return false;
//    } else {

//        qDebug() << " in image";
//    }

    if (p.x() < 0 || p.x() >= width() ||
        p.y() < 0 || p.y() >= height()){
        return false;
    } else {

      //  qDebug() << " in image";
    }


    qreal r = qBound<int>(0, m_alphaThreshold * 255, 255);
//    if (qAlpha(m_maskImage.pixel(p)) > r)
//        qDebug() << "inside";
    return qAlpha(m_maskImage.pixel(p)) > r;
}

void MaskedMouseArea::mousePressEvent(QMouseEvent *event)
{
    qDebug() << "mouse" ;
    setPressed(true);
    m_pressPoint = event->pos();
    event->setAccepted(false);
    emit pressed();
}

void MaskedMouseArea::mouseReleaseEvent(QMouseEvent *event)
{
    setPressed(false);
    emit released();

    const int threshold = qApp->styleHints()->startDragDistance();
    const bool isClick = (threshold >= qAbs(event->x() - m_pressPoint.x()) &&
                          threshold >= qAbs(event->y() - m_pressPoint.y()));

    if (isClick)
        emit clicked();
    event->setAccepted(false);
}

void MaskedMouseArea::mouseUngrabEvent()
{
    setPressed(false);
    emit canceled();
}

void MaskedMouseArea::hoverEnterEvent(QHoverEvent *event)
{
    Q_UNUSED(event);
    setContainsMouse(true);
    event->setAccepted(false);
}

void MaskedMouseArea::hoverLeaveEvent(QHoverEvent *event)
{
    Q_UNUSED(event);
    setContainsMouse(false);
    event->setAccepted(false);
}

    qmlRegisterType<MaskedMouseArea>("com.pxx.pd", 1,0, "MaskedMouseArea");

AppImage {
    id: mainImage
    property string sourceImage
    property string region
    anchors.fill: parent
    fillMode: Image.PreserveAspectFit
    smooth: true
    source: sourceImage
    MaskedMouseArea {
        id: imageMask
        anchors.fill: parent
        alphaThreshold: 0.8
        maskSource: sourceImage
        onPressed: {
            showRegion(parent, mainImage.region)
        }
        Component.onCompleted: {
            scaleToSized(width, height)
        }
    }
    Behavior on scale {
        NumberAnimation { duration: 400 }
    }
}

As I said it works on the other plattforms. So is there anything else I have to do on iOS?

Thx,

patrik