1 files changed, 119 insertions, 1 deletions

diff --git a/src/widgets/dialogs/qcolordialog.cpp b/src/widgets/dialogs/qcolordialog.cpp
index d6254076c5..5edf883e5a 100644
--- a/src/widgets/dialogs/qcolordialog.cpp
+++ b/src/widgets/dialogs/qcolordialog.cpp
@@ -63,6 +63,8 @@
 #include "qmimedata.h"
 #include "qspinbox.h"
 #include "qdialogbuttonbox.h"
+#include "qscreen.h"
+#include "qcursor.h"
 
 QT_BEGIN_NAMESPACE
 
@@ -1417,6 +1419,15 @@ bool QColorDialogPrivate::selectColor(const QColor &col)
     return false;
 }
 
+QColor QColorDialogPrivate::grabScreenColor(const QPoint &p)
+{
+    const QDesktopWidget *desktop = QApplication::desktop();
+    const QPixmap pixmap = QGuiApplication::screens().at(desktop->screenNumber())->grabWindow(desktop->winId(),
+                                                                                              p.x(), p.y(), 1, 1);
+    QImage i = pixmap.toImage();
+    return i.pixel(0, 0);
+}
+
 //sets all widgets except cs to display rgb
 void QColorDialogPrivate::_q_newColorTypedIn(QRgb rgb)
 {
@@ -1442,6 +1453,48 @@ void QColorDialogPrivate::_q_newStandard(int r, int c)
         custom->setSelected(-1,-1);
 }
 
+void QColorDialogPrivate::_q_pickScreenColor()
+{
+    Q_Q(QColorDialog);
+    screenColorPicking = true;
+    // If user pushes Escape, the last color before picking will be restored.
+    beforeScreenColorPicking = cs->currentColor();
+    /*For some reason, q->grabMouse(Qt::CrossCursor) doesn't change
+     * the cursor, and therefore I have to change it manually.
+     */
+    q->grabMouse();
+    q->setCursor(Qt::CrossCursor);
+    q->grabKeyboard();
+    /* With setMouseTracking(true) the desired color can be more precisedly picked up,
+     * and continuously pushing the mouse button is not necessary.
+     */
+    q->setMouseTracking(true);
+
+    addCusBt->setDisabled(true);
+    buttons->setDisabled(true);
+    screenColorPickerButton->setDisabled(true);
+
+    q->setCurrentColor(grabScreenColor(QCursor::pos()));
+    lblScreenColorInfo->setText(QColorDialog::tr("Cursor at %1, %2, color: %3\nPress ESC to cancel")
+                                .arg(QCursor::pos().x())
+                                .arg(QCursor::pos().y())
+                                .arg(q->currentColor().name()));
+}
+
+void QColorDialogPrivate::releaseColorPicking()
+{
+    Q_Q(QColorDialog);
+    screenColorPicking = false;
+    q->releaseMouse();
+    q->releaseKeyboard();
+    q->setCursor(Qt::ArrowCursor);
+    q->setMouseTracking(false);
+    lblScreenColorInfo->setText(QLatin1String("\n"));
+    addCusBt->setDisabled(false);
+    buttons->setDisabled(false);
+    screenColorPickerButton->setDisabled(false);
+}
+
 void QColorDialogPrivate::init(const QColor &initial)
 {
     Q_Q(QColorDialog);
@@ -1450,7 +1503,7 @@ void QColorDialogPrivate::init(const QColor &initial)
     q->setWindowTitle(QColorDialog::tr("Select Color"));
 
     nativeDialogInUse = (platformColorDialogHelper() != 0);
-
+    screenColorPicking = false;
     nextCust = 0;
     QVBoxLayout *mainLay = new QVBoxLayout(q);
     // there's nothing in this dialog that benefits from sizing up
@@ -1486,6 +1539,15 @@ void QColorDialogPrivate::init(const QColor &initial)
         leftLay->addWidget(lblBasicColors);
         leftLay->addWidget(standard);
 
+#if !defined(Q_OS_WINCE) && !defined(QT_SMALL_COLORDIALOG)
+        // The screen color picker button
+        screenColorPickerButton = new QPushButton(QColorDialog::tr("Pick Screen Color"));
+        leftLay->addWidget(screenColorPickerButton);
+        lblScreenColorInfo = new QLabel(QLatin1String("\n"));
+        leftLay->addWidget(lblScreenColorInfo);
+        q->connect(screenColorPickerButton, SIGNAL(clicked()), SLOT(_q_pickScreenColor()));
+#endif
+
 #if !defined(Q_OS_WINCE)
         leftLay->addStretch();
 #endif
@@ -1658,6 +1720,11 @@ static const Qt::WindowFlags DefaultWindowFlags =
     during the execution of the program. Use setCustomColor() to set
     the custom colors, and use customColor() to get them.
 
+    When pressing the "Pick Screen Color" button, the cursor changes to a haircross
+    and the colors on the screen are scanned. The user can pick up one by clicking
+    the mouse or the Enter button. Pressing Escape restores the last color selected
+    before entering this mode.
+
     The \l{dialogs/standarddialogs}{Standard Dialogs} example shows
     how to use QColorDialog as well as other built-in Qt dialogs.
 
@@ -1972,6 +2039,57 @@ void QColorDialog::changeEvent(QEvent *e)
 }
 
 /*!
+    \reimp
+*/
+void QColorDialog::mouseMoveEvent(QMouseEvent *e)
+{
+    Q_D(QColorDialog);
+    if (d->screenColorPicking) {
+        setCurrentColor(d->grabScreenColor(e->globalPos()));
+        d->lblScreenColorInfo->setText(QColorDialog::tr("Cursor at %1, %2, color: %3\nPress ESC to cancel")
+                                       .arg(e->globalPos().x())
+                                       .arg(e->globalPos().y())
+                                       .arg(currentColor().name()));
+        return;
+    }
+    QDialog::mouseMoveEvent(e);
+}
+
+/*!
+    \reimp
+*/
+void QColorDialog::mouseReleaseEvent(QMouseEvent *e)
+{
+    Q_D(QColorDialog);
+    if (d->screenColorPicking) {
+        setCurrentColor(d->grabScreenColor(e->globalPos()));
+        d->releaseColorPicking();
+        return;
+    }
+    QDialog::mouseReleaseEvent(e);
+}
+
+/*!
+    \reimp
+*/
+void QColorDialog::keyPressEvent(QKeyEvent *e)
+{
+    Q_D(QColorDialog);
+    if (d->screenColorPicking) {
+        if (e->key() == Qt::Key_Escape) {
+            d->releaseColorPicking();
+            d->setCurrentColor(d->beforeScreenColorPicking);
+        } else if (e->key() == Qt::Key_Return || e->key() == Qt::Key_Enter) {
+            setCurrentColor(d->grabScreenColor(QCursor::pos()));
+            d->releaseColorPicking();
+        }
+        e->accept();
+        return;
+    }
+    QDialog::keyPressEvent(e);
+}
+
+/*!
   Closes the dialog and sets its result code to \a result. If this dialog
   is shown with exec(), done() causes the local event loop to finish,
   and exec() to return \a result.