func gtkAreaNew() *C.GtkWidget {
drawingarea := C.gtk_drawing_area_new()
// the Area's size will be set later
// we need to explicitly subscribe to mouse events with GtkDrawingArea
C.gtk_widget_add_events(drawingarea,
C.GDK_BUTTON_PRESS_MASK|C.GDK_BUTTON_RELEASE_MASK|C.GDK_POINTER_MOTION_MASK|C.GDK_BUTTON_MOTION_MASK|C.GDK_ENTER_NOTIFY_MASK|C.GDK_LEAVE_NOTIFY_MASK)
// and we need to allow focusing on a GtkDrawingArea to enable keyboard events
C.gtk_widget_set_can_focus(drawingarea, C.TRUE)
scrollarea := C.gtk_scrolled_window_new((*C.GtkAdjustment)(nil), (*C.GtkAdjustment)(nil))
// need a viewport because GtkDrawingArea isn't natively scrollable
C.gtk_scrolled_window_add_with_viewport((*C.GtkScrolledWindow)(unsafe.Pointer(scrollarea)), drawingarea)
return scrollarea
}
func newArea(ab *areabase) Area {
widget := C.gtk_drawing_area_new()
// the Area's size will be set later
// we need to explicitly subscribe to mouse events with GtkDrawingArea
C.gtk_widget_add_events(widget,
C.GDK_BUTTON_PRESS_MASK|C.GDK_BUTTON_RELEASE_MASK|C.GDK_POINTER_MOTION_MASK|C.GDK_BUTTON_MOTION_MASK|C.GDK_ENTER_NOTIFY_MASK|C.GDK_LEAVE_NOTIFY_MASK)
// and we need to allow focusing on a GtkDrawingArea to enable keyboard events
C.gtk_widget_set_can_focus(widget, C.TRUE)
textfieldw := C.gtk_entry_new()
a := &area{
areabase: ab,
_widget: widget,
drawingarea: (*C.GtkDrawingArea)(unsafe.Pointer(widget)),
scroller: newScroller(widget, false, false, true), // not natively scrollable; no border; have an overlay for OpenTextFieldAt()
clickCounter: new(clickCounter),
textfieldw: textfieldw,
textfield: (*C.GtkEntry)(unsafe.Pointer(textfieldw)),
textfielddone: newEvent(),
}
for _, c := range areaCallbacks {
g_signal_connect(
C.gpointer(unsafe.Pointer(a.drawingarea)),
c.name,
c.callback,
C.gpointer(unsafe.Pointer(a)))
}
a.SetSize(a.width, a.height)
C.gtk_overlay_add_overlay(a.scroller.overlay, a.textfieldw)
g_signal_connect(
C.gpointer(unsafe.Pointer(a.scroller.overlay)),
"get-child-position",
area_get_child_position_callback,
C.gpointer(unsafe.Pointer(a)))
// this part is important
// entering the context menu is considered focusing out
// so we connect to populate-popup to mark that we're entering the context menu (thanks slaf in irc.gimp.net/#gtk+)
// and we have to connect_after to focus-out-event so that it runs after the populate-popup
g_signal_connect(
C.gpointer(unsafe.Pointer(a.textfield)),
"populate-popup",
area_textfield_populate_popup_callback,
C.gpointer(unsafe.Pointer(a)))
g_signal_connect_after(
C.gpointer(unsafe.Pointer(a.textfield)),
"focus-out-event",
area_textfield_focus_out_event_callback,
C.gpointer(unsafe.Pointer(a)))
// the widget shows up initially
C.gtk_widget_set_no_show_all(a.textfieldw, C.TRUE)
return a
}
// SetMapped is a wrapper around gtk_widget_set_mapped().
func (v *Widget) SetMapped(mapped bool) {
C.gtk_widget_set_can_focus(v.native(), gbool(mapped))
}
// SetCanFocus is a wrapper around gtk_widget_set_can_focus().
func (v *Widget) SetCanFocus(canFocus bool) {
C.gtk_widget_set_can_focus(v.native(), gbool(canFocus))
}