Ensure press-and-hold event keeps selection

This concerns TextField and TextArea.

It is an almost universal UX pattern on touch platforms where
the user long presses to pop the context menu up. In many
cases the context menu is used for copy and cut operations,
which means that poping it up should keep the selection.

The implementation works by not forwarding the initial mouse
press event to the parent class until we're sure it's not going
to be a long press. If the long press timer is cancelled for any
reason, we will then send the delayed mouse press event to the
parent class followed by whichever event triggered the cancellation.

Auto-tests refactored and updated.

Change-Id: If3aa8075f07a80929f4bd723895d9599bf8d169e
Reviewed-by: J-P Nurmi <jpnurmi@theqtcompany.com>

src/controls/qquickpressandholdhelper.cpp

@@ -45,17 +45,22 @@
 QT_BEGIN_NAMESPACE
 
 QQuickPressAndHoldHelper::QQuickPressAndHoldHelper()
-    : control(Q_NULLPTR), longPress(false), pressAndHoldSignalIndex(-1)
+    : control(Q_NULLPTR)
+    , longPress(false)
+    , pressAndHoldSignalIndex(-1)
+    , delayedMousePressEvent(Q_NULLPTR)
 { }
 
 void QQuickPressAndHoldHelper::mousePressEvent(QMouseEvent *event)
 {
     longPress = false;
     pressPos = event->localPos();
-    if (Qt::LeftButton == (event->buttons() & Qt::LeftButton))
+    if (Qt::LeftButton == (event->buttons() & Qt::LeftButton)) {
         timer.start(QGuiApplication::styleHints()->mousePressAndHoldInterval(), control);
-    else
+        delayedMousePressEvent = new QMouseEvent(event->type(), event->pos(), event->button(), event->buttons(), event->modifiers());
+    } else {
         timer.stop();
+    }
 }
 
 void QQuickPressAndHoldHelper::mouseMoveEvent(QMouseEvent *event)
@@ -73,6 +78,7 @@ void QQuickPressAndHoldHelper::mouseReleaseEvent(QMouseEvent *)
 void QQuickPressAndHoldHelper::timerEvent(QTimerEvent *)
 {
     timer.stop();
+    clearDelayedMouseEvent();
 
     if (pressAndHoldSignalIndex == -1)
         pressAndHoldSignalIndex = control->metaObject()->indexOfSignal("pressAndHold(QQuickMouseEvent*)");
@@ -92,4 +98,17 @@ void QQuickPressAndHoldHelper::timerEvent(QTimerEvent *)
     }
 }
 
+void QQuickPressAndHoldHelper::clearDelayedMouseEvent()
+{
+    if (delayedMousePressEvent) {
+        delete delayedMousePressEvent;
+        delayedMousePressEvent = 0;
+    }
+}
+
+bool QQuickPressAndHoldHelper::isActive()
+{
+    return !(timer.isActive() || longPress);
+}
+
 QT_END_NAMESPACE

src/controls/qquickpressandholdhelper_p.h

@@ -55,11 +55,15 @@ struct QQuickPressAndHoldHelper
     void mouseReleaseEvent(QMouseEvent *event);
     void timerEvent(QTimerEvent *event);
 
+    void clearDelayedMouseEvent();
+    bool isActive();
+
     QQuickItem *control;
     QBasicTimer timer;
     QPointF pressPos;
     bool longPress;
     int pressAndHoldSignalIndex;
+    QMouseEvent *delayedMousePressEvent;
 };
 
 QT_END_NAMESPACE

src/controls/qquicktextarea.cpp

@@ -260,23 +260,39 @@ void QQuickTextArea::mousePressEvent(QMouseEvent *event)
 {
     Q_D(QQuickTextArea);
     d->pressAndHoldHelper.mousePressEvent(event);
-    QQuickTextEdit::mousePressEvent(event);
+    if (d->pressAndHoldHelper.isActive()) {
+        if (d->pressAndHoldHelper.delayedMousePressEvent) {
+            QQuickTextEdit::mousePressEvent(d->pressAndHoldHelper.delayedMousePressEvent);
+            d->pressAndHoldHelper.clearDelayedMouseEvent();
+        }
+        QQuickTextEdit::mousePressEvent(event);
+    }
 }
 
 void QQuickTextArea::mouseMoveEvent(QMouseEvent *event)
 {
     Q_D(QQuickTextArea);
     d->pressAndHoldHelper.mouseMoveEvent(event);
-    if (!d->pressAndHoldHelper.timer.isActive())
+    if (d->pressAndHoldHelper.isActive()) {
+        if (d->pressAndHoldHelper.delayedMousePressEvent) {
+            QQuickTextEdit::mousePressEvent(d->pressAndHoldHelper.delayedMousePressEvent);
+            d->pressAndHoldHelper.clearDelayedMouseEvent();
+        }
         QQuickTextEdit::mouseMoveEvent(event);
+    }
 }
 
 void QQuickTextArea::mouseReleaseEvent(QMouseEvent *event)
 {
     Q_D(QQuickTextArea);
     d->pressAndHoldHelper.mouseReleaseEvent(event);
-    if (!d->pressAndHoldHelper.longPress)
+    if (d->pressAndHoldHelper.isActive()) {
+        if (d->pressAndHoldHelper.delayedMousePressEvent) {
+            QQuickTextEdit::mousePressEvent(d->pressAndHoldHelper.delayedMousePressEvent);
+            d->pressAndHoldHelper.clearDelayedMouseEvent();
+        }
         QQuickTextEdit::mouseReleaseEvent(event);
+    }
 }
 
 void QQuickTextArea::timerEvent(QTimerEvent *event)

src/controls/qquicktextfield.cpp

@@ -292,23 +292,39 @@ void QQuickTextField::mousePressEvent(QMouseEvent *event)
 {
     Q_D(QQuickTextField);
     d->pressAndHoldHelper.mousePressEvent(event);
-    QQuickTextInput::mousePressEvent(event);
+    if (d->pressAndHoldHelper.isActive()) {
+        if (d->pressAndHoldHelper.delayedMousePressEvent) {
+            QQuickTextInput::mousePressEvent(d->pressAndHoldHelper.delayedMousePressEvent);
+            d->pressAndHoldHelper.clearDelayedMouseEvent();
+        }
+        QQuickTextInput::mousePressEvent(event);
+    }
 }
 
 void QQuickTextField::mouseMoveEvent(QMouseEvent *event)
 {
     Q_D(QQuickTextField);
     d->pressAndHoldHelper.mouseMoveEvent(event);
-    if (!d->pressAndHoldHelper.timer.isActive())
+    if (d->pressAndHoldHelper.isActive()) {
+        if (d->pressAndHoldHelper.delayedMousePressEvent) {
+            QQuickTextInput::mousePressEvent(d->pressAndHoldHelper.delayedMousePressEvent);
+            d->pressAndHoldHelper.clearDelayedMouseEvent();
+        }
         QQuickTextInput::mouseMoveEvent(event);
+    }
 }
 
 void QQuickTextField::mouseReleaseEvent(QMouseEvent *event)
 {
     Q_D(QQuickTextField);
     d->pressAndHoldHelper.mouseReleaseEvent(event);
-    if (!d->pressAndHoldHelper.longPress)
+    if (d->pressAndHoldHelper.isActive()) {
+        if (d->pressAndHoldHelper.delayedMousePressEvent) {
+            QQuickTextInput::mousePressEvent(d->pressAndHoldHelper.delayedMousePressEvent);
+            d->pressAndHoldHelper.clearDelayedMouseEvent();
+        }
         QQuickTextInput::mouseReleaseEvent(event);
+    }
 }
 
 void QQuickTextField::timerEvent(QTimerEvent *event)

tests/auto/controls/data/PressAndHoldTests.qml

@@ -0,0 +1,139 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd.
+** Contact: http://www.qt.io/licensing/
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:BSD$
+** You may use this file under the terms of the BSD license as follows:
+**
+** "Redistribution and use in source and binary forms, with or without
+** modification, are permitted provided that the following conditions are
+** met:
+**   * Redistributions of source code must retain the above copyright
+**     notice, this list of conditions and the following disclaimer.
+**   * Redistributions in binary form must reproduce the above copyright
+**     notice, this list of conditions and the following disclaimer in
+**     the documentation and/or other materials provided with the
+**     distribution.
+**   * Neither the name of The Qt Company Ltd nor the names of its
+**     contributors may be used to endorse or promote products derived
+**     from this software without specific prior written permission.
+**
+**
+** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+import QtQuick 2.6
+import QtTest 1.0
+
+QtObject {
+
+    property SignalSpy pressAndHoldSpy: SignalSpy {
+        signalName: "pressAndHold"
+    }
+
+    function basicPressAndHold(control) {
+        control.width = 200
+        pressAndHoldSpy.target = control
+
+        mouseClick(control)
+        compare(pressAndHoldSpy.count, 0)
+        var interval = Qt.styleHints.mousePressAndHoldInterval
+
+        // Short press duration => nothing happens
+        mousePress(control)
+        wait(interval * 0.3)
+        mouseRelease(control)
+        compare(pressAndHoldSpy.count, 0)
+
+        // Long enough press duration => signal emitted
+        mousePress(control, 10, 10)
+        // Add 20% extra time to allow the control to
+        // receive the timer event before we come back here
+        wait(interval * 1.2)
+        compare(pressAndHoldSpy.count, 1)
+        mouseRelease(control)
+        compare(pressAndHoldSpy.count, 1)
+
+        // Long enough, but move in between => nothing happens
+        pressAndHoldSpy.clear()
+        mousePress(control)
+        wait(interval * 0.6)
+        mouseMove(control, 5, 5, Qt.LeftButton)
+        wait(interval * 0.6)
+        compare(pressAndHoldSpy.count, 0)
+        mouseRelease(control)
+        compare(pressAndHoldSpy.count, 0)
+
+        // Long enough, but 2nd press in between => nothing happens
+        pressAndHoldSpy.clear()
+        mousePress(control, 10, 10)
+        wait(interval * 0.6)
+        mousePress(control, 10, 10, Qt.RightButton)
+        wait(interval * 0.6)
+        compare(pressAndHoldSpy.count, 0)
+        mouseRelease(control, 10, 10, Qt.LeftButton|Qt.RightButton)
+        compare(pressAndHoldSpy.count, 0)
+    }
+
+    function pressAndHoldKeepsSelection(control) {
+        control.width = 200
+        control.text = "Cool stuff"
+        control.selectAll()
+        compare(control.selectedText, control.text)
+
+        mouseClick(control)
+        compare(control.selectedText, "")
+
+        control.selectAll()
+        compare(control.selectedText, control.text)
+
+        var interval = Qt.styleHints.mousePressAndHoldInterval
+        pressAndHoldSpy.target = control
+        mousePress(control, 10, 10)
+        // Add 20% extra time to allow the control to
+        // receive the timer event before we come back here
+        wait(interval * 1.2)
+        mouseRelease(control)
+        compare(pressAndHoldSpy.count, 1)
+        compare(control.selectedText, control.text)
+        pressAndHoldSpy.clear()
+
+        // Pre-timeout canceled pressAndHold should clear as usual
+        mousePress(control, 10, 10)
+        wait(interval * 0.5)
+        mouseRelease(control)
+        compare(pressAndHoldSpy.count, 0)
+        compare(control.selectedText, "")
+
+        control.selectAll()
+        compare(control.selectedText, control.text)
+
+        // Second button canceled pressAndHold should clear as usual
+        mousePress(control, 10, 10)
+        wait(interval * 0.6)
+        mouseRelease(control)
+        mousePress(control, 10, 10, Qt.RightButton)
+        compare(control.selectedText, "")
+        wait(interval * 0.6)
+        compare(pressAndHoldSpy.count, 0)
+        mouseRelease(control, 10, 10, Qt.LeftButton|Qt.RightButton)
+        compare(pressAndHoldSpy.count, 0)
+        compare(control.selectedText, "")
+    }
+}

tests/auto/controls/data/tst_textarea.qml

@@ -61,55 +61,17 @@ TestCase {
         control.destroy()
     }
 
-    SignalSpy {
-        id: pressAndHoldSpy
-        signalName: "pressAndHold"
-    }
+    PressAndHoldTests { id: pah }
 
     function test_pressAndHold() {
         var control = textArea.createObject(testCase)
-        control.width = 200
-        pressAndHoldSpy.target = control
-
-        mouseClick(control)
-        compare(pressAndHoldSpy.count, 0)
-        var interval = Qt.styleHints.mousePressAndHoldInterval
-
-        // Short press duration => nothing happens
-        mousePress(control)
-        wait(interval * 0.3)
-        mouseRelease(control)
-        compare(pressAndHoldSpy.count, 0)
-
-        // Long enough press duration => signal emitted
-        mousePress(control, 10, 10)
-        // Add 20% extra time to allow the control to
-        // receive the timer event before we come back here
-        wait(interval * 1.2)
-        compare(pressAndHoldSpy.count, 1)
-        mouseRelease(control)
-        compare(pressAndHoldSpy.count, 1)
-
-        // Long enough, but move in between => nothing happens
-        pressAndHoldSpy.clear()
-        mousePress(control)
-        wait(interval * 0.6)
-        mouseMove(control, 5, 5, Qt.LeftButton)
-        wait(interval * 0.6)
-        compare(pressAndHoldSpy.count, 0)
-        mouseRelease(control)
-        compare(pressAndHoldSpy.count, 0)
-
-        // Long enough, but 2nd press in between => nothing happens
-        pressAndHoldSpy.clear()
-        mousePress(control, 10, 10)
-        wait(interval * 0.6)
-        mousePress(control, 10, 10, Qt.RightButton)
-        wait(interval * 0.6)
-        compare(pressAndHoldSpy.count, 0)
-        mouseRelease(control, 10, 10, Qt.LeftButton|Qt.RightButton)
-        compare(pressAndHoldSpy.count, 0)
+        pah.basicPressAndHold(control)
+        control.destroy()
+    }
 
+    function test_pressAndHoldKeepsSelection() {
+        var control = textArea.createObject(testCase)
+        pah.pressAndHoldKeepsSelection(control)
         control.destroy()
     }
 }

tests/auto/controls/data/tst_textfield.qml

@@ -61,58 +61,20 @@ TestCase {
         control.destroy()
     }
 
-    SignalSpy {
-        id: pressAndHoldSpy
-        signalName: "pressAndHold"
-    }
+    PressAndHoldTests { id: pah }
 
     function test_pressAndHold() {
         if (Qt.platform.os === "osx")
             skip("QTBUG-47963");
 
         var control = textField.createObject(testCase)
-        control.width = 200
-        pressAndHoldSpy.target = control
-
-        mouseClick(control)
-        compare(pressAndHoldSpy.count, 0)
-        var interval = Qt.styleHints.mousePressAndHoldInterval
-
-        // Short press duration => nothing happens
-        mousePress(control)
-        wait(interval * 0.3)
-        mouseRelease(control)
-        compare(pressAndHoldSpy.count, 0)
-
-        // Long enough press duration => signal emitted
-        mousePress(control, 10, 10)
-        // Add 20% extra time to allow the control to
-        // receive the timer event before we come back here
-        wait(interval * 1.2)
-        compare(pressAndHoldSpy.count, 1)
-        mouseRelease(control)
-        compare(pressAndHoldSpy.count, 1)
-
-        // Long enough, but move in between => nothing happens
-        pressAndHoldSpy.clear()
-        mousePress(control)
-        wait(interval * 0.6)
-        mouseMove(control, 5, 5, Qt.LeftButton)
-        wait(interval * 0.6)
-        compare(pressAndHoldSpy.count, 0)
-        mouseRelease(control)
-        compare(pressAndHoldSpy.count, 0)
-
-        // Long enough, but 2nd press in between => nothing happens
-        pressAndHoldSpy.clear()
-        mousePress(control, 10, 10)
-        wait(interval * 0.6)
-        mousePress(control, 10, 10, Qt.RightButton)
-        wait(interval * 0.6)
-        compare(pressAndHoldSpy.count, 0)
-        mouseRelease(control, 10, 10, Qt.LeftButton|Qt.RightButton)
-        compare(pressAndHoldSpy.count, 0)
+        pah.basicPressAndHold(control)
+        control.destroy()
+    }
 
+    function test_pressAndHoldKeepsSelection() {
+        var control = textField.createObject(testCase)
+        pah.pressAndHoldKeepsSelection(control)
         control.destroy()
     }
 }