gtk2/demos/gtk-demo/clipboard.c
2020-01-30 10:53:43 +01:00

403 lines
12 KiB
C

/* Clipboard
*
* GdkClipboard is used for clipboard handling. This demo shows how to
* copy and paste text to and from the clipboard.
*
* It also shows how to transfer images via the clipboard or via
* drag-and-drop, and how to make clipboard contents persist after
* the application exits. Clipboard persistence requires a clipboard
* manager to run.
*/
#include <glib/gi18n.h>
#include <gtk/gtk.h>
#include <string.h>
static GtkWidget *window = NULL;
void
copy_button_clicked (GtkWidget *button,
gpointer user_data)
{
GtkWidget *entry;
GdkClipboard *clipboard;
entry = GTK_WIDGET (user_data);
/* Get the clipboard object */
clipboard = gtk_widget_get_clipboard (entry);
/* Set clipboard text */
gdk_clipboard_set_text (clipboard, gtk_editable_get_text (GTK_EDITABLE (entry)));
}
void
paste_received (GObject *source_object,
GAsyncResult *result,
gpointer user_data)
{
GdkClipboard *clipboard;
GtkWidget *entry;
char *text;
GError *error = NULL;
clipboard = GDK_CLIPBOARD (source_object);
entry = GTK_WIDGET (user_data);
/* Get the resulting text of the read operation */
text = gdk_clipboard_read_text_finish (clipboard, result, &error);
if (text)
{
/* Set the entry text */
gtk_editable_set_text (GTK_EDITABLE (entry), text);
g_free (text);
}
else
{
GtkWidget *dialog;
/* Show an error about why pasting failed.
* Usually you probably want to ignore such failures,
* but for demonstration purposes, we show the error.
*/
dialog = gtk_message_dialog_new (GTK_WINDOW (window),
GTK_DIALOG_DESTROY_WITH_PARENT | GTK_DIALOG_MODAL,
GTK_MESSAGE_ERROR,
GTK_BUTTONS_CLOSE,
"Could not paste text: %s",
error->message);
g_signal_connect (dialog, "response",
G_CALLBACK (gtk_widget_destroy), NULL);
gtk_widget_show (dialog);
g_error_free (error);
}
}
void
paste_button_clicked (GtkWidget *button,
gpointer user_data)
{
GtkWidget *entry;
GdkClipboard *clipboard;
entry = GTK_WIDGET (user_data);
/* Get the clipboard object */
clipboard = gtk_widget_get_clipboard (entry);
/* Request the contents of the clipboard, contents_received will be
called when we do get the contents.
*/
gdk_clipboard_read_text_async (clipboard, NULL, paste_received, entry);
}
static GdkPaintable *
get_image_paintable (GtkImage *image)
{
const gchar *icon_name;
GtkIconTheme *icon_theme;
GtkIcon *icon;
switch (gtk_image_get_storage_type (image))
{
case GTK_IMAGE_PAINTABLE:
return g_object_ref (gtk_image_get_paintable (image));
case GTK_IMAGE_ICON_NAME:
icon_name = gtk_image_get_icon_name (image);
icon_theme = gtk_icon_theme_get_for_display (gtk_widget_get_display (GTK_WIDGET (image)));
icon = gtk_icon_theme_lookup_icon (icon_theme, icon_name, 48, 1, GTK_ICON_LOOKUP_GENERIC_FALLBACK);
if (icon == NULL)
return NULL;
return GDK_PAINTABLE (icon);
default:
g_warning ("Image storage type %d not handled",
gtk_image_get_storage_type (image));
return NULL;
}
}
static void
drag_begin (GtkDragSource *source,
GdkDrag *drag,
GtkWidget *widget)
{
GdkPaintable *paintable;
paintable = get_image_paintable (GTK_IMAGE (widget));
if (paintable)
{
gtk_drag_source_set_icon (source, paintable, -2, -2);
g_object_unref (paintable);
}
}
static void
get_texture (GValue *value,
gpointer data)
{
GdkPaintable *paintable = get_image_paintable (GTK_IMAGE (data));
if (GDK_IS_TEXTURE (paintable))
g_value_set_object (value, paintable);
}
static GdkContentProvider *
prepare_drag (GtkDragSource *source,
double x,
double y,
GtkWidget *image)
{
return gdk_content_provider_new_with_callback (GDK_TYPE_TEXTURE, get_texture, image);
}
static void
got_texture (GObject *source,
GAsyncResult *result,
gpointer data)
{
GdkDrop *drop = GDK_DROP (source);
GtkWidget *image = data;
const GValue *value;
GError *error = NULL;
value = gdk_drop_read_value_finish (drop, result, &error);
if (value)
{
GdkTexture *texture = g_value_get_object (value);
gtk_image_set_from_paintable (GTK_IMAGE (image), GDK_PAINTABLE (texture));
}
else
{
g_print ("Failed to get data: %s\n", error->message);
g_error_free (error);
}
}
static gboolean
drag_drop (GtkDropTarget *dest,
GdkDrop *drop,
int x,
int y,
GtkWidget *widget)
{
if (gdk_drop_has_value (drop, GDK_TYPE_TEXTURE))
{
gdk_drop_read_value_async (drop, GDK_TYPE_TEXTURE, G_PRIORITY_DEFAULT, NULL, got_texture, widget);
return TRUE;
}
return FALSE;
}
static void
copy_image (GSimpleAction *action,
GVariant *value,
gpointer data)
{
GdkClipboard *clipboard = gtk_widget_get_clipboard (GTK_WIDGET (data));
GdkPaintable *paintable = get_image_paintable (GTK_IMAGE (data));
if (GDK_IS_TEXTURE (paintable))
gdk_clipboard_set_texture (clipboard, GDK_TEXTURE (paintable));
if (paintable)
g_object_unref (paintable);
}
static void
paste_image_received (GObject *source,
GAsyncResult *result,
gpointer data)
{
GdkTexture *texture;
texture = gdk_clipboard_read_texture_finish (GDK_CLIPBOARD (source), result, NULL);
if (texture == NULL)
return;
gtk_image_set_from_paintable (GTK_IMAGE (data), GDK_PAINTABLE (texture));
g_object_unref (texture);
}
static void
paste_image (GSimpleAction *action,
GVariant *value,
gpointer data)
{
GdkClipboard *clipboard = gtk_widget_get_clipboard (GTK_WIDGET (data));
gdk_clipboard_read_texture_async (clipboard, NULL, paste_image_received, data);
}
static void
pressed_cb (GtkGesture *gesture,
int n_press,
double x,
double y,
GtkWidget *image)
{
GtkWidget *popover;
GMenu *menu;
GMenuItem *item;
menu = g_menu_new ();
item = g_menu_item_new (_("_Copy"), "clipboard.copy");
g_menu_append_item (menu, item);
item = g_menu_item_new (_("_Paste"), "clipboard.paste");
g_menu_append_item (menu, item);
popover = gtk_popover_menu_new_from_model (image, G_MENU_MODEL (menu));
gtk_popover_set_pointing_to (GTK_POPOVER (popover), &(GdkRectangle) { x, y, 1, 1});
gtk_popover_popup (GTK_POPOVER (popover));
g_object_unref (menu);
}
GtkWidget *
do_clipboard (GtkWidget *do_widget)
{
if (!window)
{
GtkWidget *vbox, *hbox;
GtkWidget *label;
GtkWidget *entry, *button;
GtkWidget *image;
GtkGesture *gesture;
GActionEntry entries[] = {
{ "copy", copy_image, NULL, NULL, NULL },
{ "paste", paste_image, NULL, NULL, NULL },
};
GActionGroup *actions;
GtkDragSource *source;
GtkDropTarget *dest;
GdkContentFormats *formats;
window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
gtk_window_set_display (GTK_WINDOW (window),
gtk_widget_get_display (do_widget));
gtk_window_set_title (GTK_WINDOW (window), "Clipboard");
g_signal_connect (window, "destroy",
G_CALLBACK (gtk_widget_destroyed), &window);
vbox = gtk_box_new (GTK_ORIENTATION_VERTICAL, 0);
g_object_set (vbox, "margin", 8, NULL);
gtk_container_add (GTK_CONTAINER (window), vbox);
label = gtk_label_new ("\"Copy\" will copy the text\nin the entry to the clipboard");
gtk_container_add (GTK_CONTAINER (vbox), label);
hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 4);
g_object_set (hbox, "margin", 8, NULL);
gtk_container_add (GTK_CONTAINER (vbox), hbox);
/* Create the first entry */
entry = gtk_entry_new ();
gtk_container_add (GTK_CONTAINER (hbox), entry);
/* Create the button */
button = gtk_button_new_with_mnemonic (_("_Copy"));
gtk_container_add (GTK_CONTAINER (hbox), button);
g_signal_connect (button, "clicked",
G_CALLBACK (copy_button_clicked), entry);
label = gtk_label_new ("\"Paste\" will paste the text from the clipboard to the entry");
gtk_container_add (GTK_CONTAINER (vbox), label);
hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 4);
g_object_set (hbox, "margin", 8, NULL);
gtk_container_add (GTK_CONTAINER (vbox), hbox);
/* Create the second entry */
entry = gtk_entry_new ();
gtk_container_add (GTK_CONTAINER (hbox), entry);
/* Create the button */
button = gtk_button_new_with_mnemonic (_("_Paste"));
gtk_container_add (GTK_CONTAINER (hbox), button);
g_signal_connect (button, "clicked",
G_CALLBACK (paste_button_clicked), entry);
label = gtk_label_new ("Images can be transferred via the clipboard, too");
gtk_container_add (GTK_CONTAINER (vbox), label);
hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 4);
g_object_set (hbox, "margin", 8, NULL);
gtk_container_add (GTK_CONTAINER (vbox), hbox);
/* Create the first image */
image = gtk_image_new_from_icon_name ("dialog-warning");
gtk_image_set_pixel_size (GTK_IMAGE (image), 48);
gtk_container_add (GTK_CONTAINER (hbox), image);
/* make image a drag source */
source = gtk_drag_source_new ();
g_signal_connect (source, "prepare", G_CALLBACK (prepare_drag), NULL);
g_signal_connect (source, "drag-begin", G_CALLBACK (drag_begin), image);
gtk_widget_add_controller (image, GTK_EVENT_CONTROLLER (source));
/* accept drops on image */
formats = gdk_content_formats_new_for_gtype (GDK_TYPE_TEXTURE);
dest = gtk_drop_target_new (formats, GDK_ACTION_COPY);
gdk_content_formats_unref (formats);
g_signal_connect (dest, "drag-drop", G_CALLBACK (drag_drop), image);
gtk_widget_add_controller (image, GTK_EVENT_CONTROLLER (dest));
/* context menu on image */
gesture = gtk_gesture_click_new ();
gtk_gesture_single_set_button (GTK_GESTURE_SINGLE (gesture), GDK_BUTTON_SECONDARY);
g_signal_connect (gesture, "pressed", G_CALLBACK (pressed_cb), image);
gtk_widget_add_controller (image, GTK_EVENT_CONTROLLER (gesture));
actions = G_ACTION_GROUP (g_simple_action_group_new ());
g_action_map_add_action_entries (G_ACTION_MAP (actions), entries, G_N_ELEMENTS (entries), image);
gtk_widget_insert_action_group (image, "clipboard", actions);
g_object_unref (actions);
/* Create the second image */
image = gtk_image_new_from_icon_name ("process-stop");
gtk_image_set_pixel_size (GTK_IMAGE (image), 48);
gtk_container_add (GTK_CONTAINER (hbox), image);
/* make image a drag source */
source = gtk_drag_source_new ();
g_signal_connect (source, "prepare", G_CALLBACK (prepare_drag), NULL);
g_signal_connect (source, "drag-begin", G_CALLBACK (drag_begin), image);
gtk_widget_add_controller (image, GTK_EVENT_CONTROLLER (source));
/* accept drops on image */
formats = gdk_content_formats_new_for_gtype (GDK_TYPE_TEXTURE);
dest = gtk_drop_target_new (formats, GDK_ACTION_COPY);
gdk_content_formats_unref (formats);
g_signal_connect (dest, "drag-drop", G_CALLBACK (drag_drop), image);
gtk_widget_add_controller (image, GTK_EVENT_CONTROLLER (dest));
/* context menu on image */
gesture = gtk_gesture_click_new ();
gtk_gesture_single_set_button (GTK_GESTURE_SINGLE (gesture), GDK_BUTTON_SECONDARY);
g_signal_connect (gesture, "pressed", G_CALLBACK (pressed_cb), image);
gtk_widget_add_controller (image, GTK_EVENT_CONTROLLER (gesture));
actions = G_ACTION_GROUP (g_simple_action_group_new ());
g_action_map_add_action_entries (G_ACTION_MAP (actions), entries, G_N_ELEMENTS (entries), image);
gtk_widget_insert_action_group (image, "clipboard", actions);
g_object_unref (actions);
}
if (!gtk_widget_get_visible (window))
gtk_widget_show (window);
else
gtk_widget_destroy (window);
return window;
}