Implemented uiColorButton on GTK+.

unix/GNUfiles.mk

@@ -7,6 +7,7 @@ CFILES += \
 	unix/button.c \
 	unix/checkbox.c \
 	unix/child.c \
+	unix/colorbutton.c \
 	unix/combobox.c \
 	unix/control.c \
 	unix/datetimepicker.c \

unix/colorbutton.c

@@ -0,0 +1,80 @@
+// 15 may 2016
+#include "uipriv_unix.h"
+
+struct uiColorButton {
+	uiUnixControl c;
+	GtkWidget *widget;
+	GtkButton *button;
+	GtkColorButton *cb;
+	GtkColorChooser *cc;
+	void (*onChanged)(uiColorButton *, void *);
+	void *onChangedData;
+};
+
+uiUnixControlAllDefaults(uiColorButton)
+
+static void onColorSet(GtkColorButton *button, gpointer data)
+{
+	uiColorButton *b = uiColorButton(data);
+
+	(*(b->onChanged))(b, b->onChangedData);
+}
+
+static void defaultOnChanged(uiColorButton *b, void *data)
+{
+	// do nothing
+}
+
+void uiColorButtonColor(uiColorButton *b, double *r, double *g, double *bl, double *a)
+{
+	GdkRGBA rgba;
+
+	gtk_color_chooser_get_rgba(b->cc, &rgba);
+	*r = rgba.red;
+	*g = rgba.green;
+	*bl = rgba.blue;
+	*a = rgba.alpha;
+}
+
+void uiColorButtonSetColor(uiColorButton *b, double r, double g, double bl, double a)
+{
+	GdkRGBA rgba;
+
+	rgba.red = r;
+	rgba.green = g;
+	rgba.blue = bl;
+	rgba.alpha = a;
+	// no need to inhibit the signal; color-set is documented as only being sent when the user changes the color
+	gtk_color_chooser_set_rgba(b->cc, &rgba);
+}
+
+void uiColorButtonOnChanged(uiColorButton *b, void (*f)(uiColorButton *, void *), void *data)
+{
+	b->onChanged = f;
+	b->onChangedData = data;
+}
+
+uiColorButton *uiNewColorButton(void)
+{
+	uiColorButton *b;
+	GdkRGBA black;
+
+	uiUnixNewControl(uiColorButton, b);
+
+	// I'm not sure what the initial color is; set up a real one
+	black.red = 0.0;
+	black.green = 0.0;
+	black.blue = 0.0;
+	black.alpha = 1.0;
+	b->widget = gtk_color_button_new_with_rgba(&black);
+	b->button = GTK_BUTTON(b->widget);
+	b->cb = GTK_COLOR_BUTTON(b->widget);
+	b->cc = GTK_COLOR_CHOOSER(b->widget);
+
+	gtk_color_chooser_set_use_alpha(b->cc, TRUE);
+
+	g_signal_connect(b->widget, "color-set", G_CALLBACK(onColorSet), b);
+	uiColorButtonOnChanged(b, defaultOnChanged, NULL);
+
+	return b;
+}