Support touchscreen tap and hold to be used instead of right mouse click.

sdrgui/gui/crightclickenabler.cpp

@@ -1,13 +1,93 @@
-/*
- * crightclickenabler.cpp
- *
- *  Created on: Mar 26, 2018
- *      Author: f4exb
- */
+///////////////////////////////////////////////////////////////////////////////////
+// Copyright (C) 2018 F4EXB                                                      //
+// written by Edouard Griffiths                                                  //
+//                                                                               //
+// This program is free software; you can redistribute it and/or modify          //
+// it under the terms of the GNU General Public License as published by          //
+// the Free Software Foundation as version 3 of the License, or                  //
+// (at your option) any later version.                                           //
+//                                                                               //
+// This program is distributed in the hope that it will be useful,               //
+// but WITHOUT ANY WARRANTY; without even the implied warranty of                //
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the                  //
+// GNU General Public License V3 for more details.                               //
+//                                                                               //
+// You should have received a copy of the GNU General Public License             //
+// along with this program. If not, see <http://www.gnu.org/licenses/>.          //
+///////////////////////////////////////////////////////////////////////////////////
+
+#include <QMouseEvent>
+#include <QGestureEvent>
+#include <QGesture>
+#include <QTapAndHoldGesture>
 
 #include "crightclickenabler.h"
 
-CRightClickEnabler::CRightClickEnabler(QAbstractButton *button): QObject(button), _button(button) {
-        button->installEventFilter(this);
-};
+CRightClickEnabler::CRightClickEnabler(QWidget *widget) :
+    QObject(widget),
+    m_widget(widget),
+    m_mousePressed(false)
+{
+    m_widget->installEventFilter(this);
+    m_widget->grabGesture(Qt::TapAndHoldGesture);
+}
 
+bool CRightClickEnabler::eventFilter(QObject *obj, QEvent *event)
+{
+    if (event->type() == QEvent::MouseButtonPress)
+    {
+        auto mouseEvent = (QMouseEvent*) event;
+
+        if (mouseEvent->button() == Qt::RightButton)
+        {
+            emit rightClick(mouseEvent->globalPos());
+            mouseEvent->setAccepted(true);
+            return true;
+        }
+
+        if (mouseEvent->button() == Qt::LeftButton)
+        {
+            if (mouseEvent->source() == Qt::MouseEventNotSynthesized) {
+                m_mousePressed = true;
+            } else {
+                m_mousePressed = false; // Mouse event generated from touch event
+            }
+        }
+    }
+    else if (event->type() == QEvent::MouseButtonRelease)
+    {
+        auto mouseEvent = (QMouseEvent*) event;
+
+        if (mouseEvent->button() == Qt::RightButton)
+        {
+            mouseEvent->setAccepted(true);
+            return true;
+        }
+
+        if (mouseEvent->button() == Qt::LeftButton) {
+            m_mousePressed = false;
+        }
+    }
+    else if (event->type() == QEvent::Gesture)
+    {
+        // Use tap and hold as right click on touch screens
+        if (!m_mousePressed)
+        {
+            QGestureEvent *gestureEvent = static_cast<QGestureEvent *>(event);
+            if (QTapAndHoldGesture *tapAndHold = static_cast<QTapAndHoldGesture *>(gestureEvent->gesture(Qt::TapAndHoldGesture)))
+            {
+                if (tapAndHold->state() == Qt::GestureFinished) {
+                    emit rightClick(tapAndHold->position().toPoint());
+                }
+                return true;
+            }
+        }
+    }
+    else if (event->type() == QEvent::ContextMenu)
+    {
+        // Filter ContextMenu events, so we don't get popup menus as well
+        return true;
+    }
+
+    return QObject::eventFilter(obj, event);
+}

sdrgui/gui/crightclickenabler.h

@@ -19,38 +19,24 @@
 #ifndef SDRGUI_GUI_CRIGHTCLICKENABLER_H_
 #define SDRGUI_GUI_CRIGHTCLICKENABLER_H_
 
-#include <QAbstractButton>
-#include <QMouseEvent>
+#include <QWidget>
 
 #include "export.h"
 
 class SDRGUI_API CRightClickEnabler : public QObject {
     Q_OBJECT
 public:
-    CRightClickEnabler(QAbstractButton *button);
+    CRightClickEnabler(QWidget *widget);
 
 signals:
-    void rightClick(const QPoint&);
+    void rightClick(const QPoint&);  // Emitted for right mouse click and touch tap and hold
 
 protected:
-    inline bool eventFilter(QObject *watched, QEvent *event) override
-    {
-        (void) watched;
-
-        if (event->type() == QEvent::MouseButtonPress)
-        {
-            auto mouseEvent = (QMouseEvent*) event;
-
-            if (mouseEvent->button() == Qt::RightButton) {
-                emit rightClick(mouseEvent->globalPos());
-            }
-        }
-
-        return false;
-    }
+    bool eventFilter(QObject *watched, QEvent *event) override;
 
 private:
-    QAbstractButton* _button;
+    QWidget* m_widget;
+    bool m_mousePressed;
 };
 
 #endif /* SDRGUI_GUI_CRIGHTCLICKENABLER_H_ */