Move internals of QgsColorDialogV2 to new QgsCompoundColorWidget widget

This allows reuse of the full options from the color dialog when
required in a widget form.

python/gui/gui.sip

@@ -53,6 +53,7 @@
 %Include qgscomposeritemcombobox.sip
 %Include qgscomposerruler.sip
 %Include qgscomposerview.sip
+%Include qgscompoundcolorwidget.sip
 %Include qgscredentialdialog.sip
 %Include qgsdatadefinedbutton.sip
 %Include qgsdetaileditemdata.sip

python/gui/qgscolordialog.sip

@@ -114,11 +114,4 @@ class QgsColorDialogV2 : QDialog
 
     void closeEvent( QCloseEvent* e );
 
-    void mousePressEvent( QMouseEvent* e );
-
-    void mouseMoveEvent( QMouseEvent *e );
-
-    void mouseReleaseEvent( QMouseEvent *e );
-
-    void keyPressEvent( QKeyEvent *e );
 };

python/gui/qgscompoundcolorwidget.sip

@@ -0,0 +1,64 @@
+
+/** \ingroup gui
+ * \class QgsCompoundColorWidget
+ * A custom QGIS widget for selecting a color, including options for selecting colors via
+ * hue wheel, color swatches, and a color sampler.
+ * \note Added in version 2.16
+ */
+
+class QgsCompoundColorWidget : QWidget
+{
+%TypeHeaderCode
+#include <qgscompoundcolorwidget.h>
+%End
+
+  public:
+
+    /** Constructor for QgsCompoundColorWidget
+     * @param parent parent widget
+     * @param color initial color for dialog
+     */
+    QgsCompoundColorWidget( QWidget *parent /TransferThis/ = nullptr, const QColor& color = QColor() );
+
+    ~QgsCompoundColorWidget();
+
+    /** Returns the current color for the dialog
+     * @returns dialog color
+     */
+    QColor color() const;
+
+    /** Sets whether alpha modification (transparency) is permitted
+     * for the color dialog. Defaults to true.
+     * @param allowAlpha set to false to disable alpha modification
+     */
+    void setAllowAlpha( const bool allowAlpha );
+
+  signals:
+
+    /** Emitted when the dialog's color changes
+     * @param color current color
+     */
+    void currentColorChanged( const QColor &color );
+
+  public slots:
+
+    /** Sets the current color for the dialog
+     * @param color desired color
+     */
+    void setColor( const QColor &color );
+
+    /** Sets the color to show in an optional "previous color" section
+     * @param color previous color
+     */
+    void setPreviousColor( const QColor& color );
+
+  protected:
+
+    void mousePressEvent( QMouseEvent* e );
+
+    void mouseMoveEvent( QMouseEvent *e );
+
+    void mouseReleaseEvent( QMouseEvent *e );
+
+    void keyPressEvent( QKeyEvent *e );
+};

src/gui/CMakeLists.txt

@@ -181,6 +181,7 @@ SET(QGIS_GUI_SRCS
   qgscomposeritemcombobox.cpp
   qgscomposerruler.cpp
   qgscomposerview.cpp
+  qgscompoundcolorwidget.cpp
   qgscredentialdialog.cpp
   qgscursors.cpp
   qgsdatadefinedbutton.cpp
@@ -328,6 +329,7 @@ SET(QGIS_GUI_MOC_HDRS
   qgscomposeritemcombobox.h
   qgscomposerruler.h
   qgscomposerview.h
+  qgscompoundcolorwidget.h
   qgscredentialdialog.h
   qgsdatadefinedbutton.h
   qgsdatumtransformdialog.h