diff options
Diffstat (limited to 'packages/gtk2/examples/scribble_simple/scribble_simple.pas')
| -rw-r--r-- | packages/gtk2/examples/scribble_simple/scribble_simple.pas | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/packages/gtk2/examples/scribble_simple/scribble_simple.pas b/packages/gtk2/examples/scribble_simple/scribble_simple.pas new file mode 100644 index 0000000000..7f43717689 --- /dev/null +++ b/packages/gtk2/examples/scribble_simple/scribble_simple.pas @@ -0,0 +1,170 @@ +program scribble_simple; + +{$mode objfpc} {$H+} + +uses glib2, gtk2, gdk2; + +var + pixmap : PGdkPixmap; (* Backing pixmap for drawing area *) + + + +(* Create a new backing pixmap of the appropriate size *) + +function configure_event ( widget : PGtkWidget; + event : PGdkEventConfigure): gboolean; cdecl; +begin + + if pixmap <> nil then + g_object_unref (pixmap); + + pixmap := gdk_pixmap_new (widget^.window, + widget^.allocation.width, + widget^.allocation.height, + -1); + gdk_draw_rectangle (pixmap, + widget^.style^.white_gc, + gTRUE, + 0, 0, + widget^.allocation.width, + widget^.allocation.height); + + configure_event := TRUE; +end; + +(* Redraw the screen from the backing pixmap *) +function expose_event ( widget : PGtkWidget; + event : PGdkEventExpose) : gboolean; cdecl; +begin + gdk_draw_drawable (widget^.window, + widget^.style^.fg_gc[GTK_WIDGET_STATE (widget)], + pixmap, + event^.area.x, event^.area.y, + event^.area.x, event^.area.y, + event^.area.width, event^.area.height); + + expose_event := FALSE; +end; + + +(* Draw a rectangle on the screen *) +procedure draw_brush (widget : PGtkWidget; + x, y : gdouble); cdecl; +var + update_rect : TGdkRectangle; + +begin + update_rect.x := round (x - 5.0); + update_rect.y := round (y - 5.0); + update_rect.width := 10; + update_rect.height := 10; + + gdk_draw_rectangle (pixmap, + widget^.style^.black_gc, + gTRUE, + update_rect.x, update_rect.y, + update_rect.width, update_rect.height); + + gtk_widget_queue_draw_area (widget, + update_rect.x, update_rect.y, + update_rect.width, update_rect.height); +end; + +function button_press_event ( widget : PGtkWidget; + event : PGdkEventbutton): gboolean; cdecl; +begin + if (event^.button = 1) and (pixmap <> NULL) then + draw_brush (widget, event^.x, event^.y); + + button_press_event := TRUE; +end; + +function motion_notify_event ( widget: PGtkWidget; + event : PGdkEventMotion): gboolean; cdecl; +var + x, y : gint; + state : TGdkModifierType; + +begin + if event^.is_hint = gTRUE then + gdk_window_get_pointer (event^.window, @x, @y, @state) + else begin + x := round (event^.x); + y := round (event^.y); + state := event^.state; + end; + + if ((state and GDK_BUTTON1_MASK) <> 0) and (pixmap <> NULL) then + draw_brush (widget, x, y); + + motion_notify_event := TRUE; +end; + +procedure quit; +begin + halt; +end; + +var + window, + drawing_area, + vbox : PGtkWidget; + + button : PGtkWidget; + +begin + gtk_init (@argc, @argv); + + window := gtk_window_new (GTK_WINDOW_TOPLEVEL); + gtk_widget_set_name (window, 'Test Input'); + + vbox := gtk_vbox_new (FALSE, 0); + gtk_container_add (GTK_CONTAINER (window), vbox); + gtk_widget_show (vbox); + + g_signal_connect (G_OBJECT (window), 'destroy', + G_CALLBACK (@quit), NULL); + + (* Create the drawing area *) + + drawing_area := gtk_drawing_area_new (); + gtk_widget_set_size_request (GTK_WIDGET (drawing_area), 200, 200); + gtk_box_pack_start (GTK_BOX (vbox), drawing_area, TRUE, TRUE, 0); + + gtk_widget_show (drawing_area); + + (* Signals used to handle backing pixmap *) + + g_signal_connect (G_OBJECT (drawing_area), 'expose_event', + G_CALLBACK (@expose_event), NULL); + + g_signal_connect (G_OBJECT (drawing_area),'configure_event', + G_CALLBACK (@configure_event), NULL); + + (* Event signals *) + + g_signal_connect (G_OBJECT (drawing_area), 'motion_notify_event', + G_CALLBACK (@motion_notify_event), NULL); + + g_signal_connect (G_OBJECT (drawing_area), 'button_press_event', + G_CALLBACK (@button_press_event), NULL); + + gtk_widget_set_events (drawing_area, GDK_EXPOSURE_MASK + or GDK_LEAVE_NOTIFY_MASK + or GDK_BUTTON_PRESS_MASK + or GDK_POINTER_MOTION_MASK + or GDK_POINTER_MOTION_HINT_MASK); + + (* .. And a quit button *) + button := gtk_button_new_with_label ('Quit'); + gtk_box_pack_start (GTK_BOX (vbox), button, FALSE, FALSE, 0); + + g_signal_connect_swapped (G_OBJECT (button), 'clicked', + G_CALLBACK (@gtk_widget_destroy), + window); + gtk_widget_show (button); + + gtk_widget_show (window); + + gtk_main (); +end. |