gtk2/demos/gtk-demo/clipboard.c
2017-12-03 05:46:49 +01:00

361 lines
11 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_entry_get_text (GTK_ENTRY (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_entry_set_text (GTK_ENTRY (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 GdkTexture *
get_image_texture (GtkImage *image)
{
const gchar *icon_name;
GtkIconTheme *icon_theme;
GtkIconInfo *icon_info;
switch (gtk_image_get_storage_type (image))
{
case GTK_IMAGE_TEXTURE:
return g_object_ref (gtk_image_get_texture (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_info = gtk_icon_theme_lookup_icon (icon_theme, icon_name, 48, GTK_ICON_LOOKUP_GENERIC_FALLBACK);
if (icon_info == NULL)
return NULL;
return gtk_icon_info_load_texture (icon_info);
default:
g_warning ("Image storage type %d not handled",
gtk_image_get_storage_type (image));
return NULL;
}
}
static void
drag_begin (GtkWidget *widget,
GdkDragContext *context,
gpointer data)
{
GdkTexture *texture;
texture = get_image_texture (GTK_IMAGE (widget));
if (texture)
gtk_drag_set_icon_texture (context, texture, -2, -2);
}
void
drag_data_get (GtkWidget *widget,
GdkDragContext *context,
GtkSelectionData *selection_data,
guint info,
guint time,
gpointer data)
{
GdkTexture *texture;
texture = get_image_texture (GTK_IMAGE (widget));
if (texture)
gtk_selection_data_set_texture (selection_data, texture);
}
static void
drag_data_received (GtkWidget *widget,
GdkDragContext *context,
gint x,
gint y,
GtkSelectionData *selection_data,
guint32 time,
gpointer data)
{
if (gtk_selection_data_get_length (selection_data) > 0)
{
GdkTexture *texture;
texture = gtk_selection_data_get_texture (selection_data);
gtk_image_set_from_texture (GTK_IMAGE (data), texture);
g_object_unref (texture);
}
}
static void
copy_image (GtkMenuItem *item,
gpointer data)
{
GdkClipboard *clipboard;
GdkTexture *texture;
clipboard = gtk_widget_get_clipboard (GTK_WIDGET (data));
texture = get_image_texture (GTK_IMAGE (data));
if (texture)
{
gdk_clipboard_set_texture (clipboard, texture);
g_object_unref (texture);
}
}
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_texture (GTK_IMAGE (data), texture);
g_object_unref (texture);
}
static void
paste_image (GtkMenuItem *item,
gpointer data)
{
GdkClipboard *clipboard;
clipboard = gtk_widget_get_clipboard (GTK_WIDGET (data));
gdk_clipboard_read_texture_async (clipboard,
NULL,
paste_image_received,
data);
}
static gboolean
button_press (GtkWidget *widget,
GdkEventButton *event,
gpointer data)
{
GtkWidget *menu;
GtkWidget *item;
guint button;
gdk_event_get_button ((GdkEvent *)event, &button);
if (button != GDK_BUTTON_SECONDARY)
return FALSE;
menu = gtk_menu_new ();
item = gtk_menu_item_new_with_mnemonic (_("_Copy"));
g_signal_connect (item, "activate", G_CALLBACK (copy_image), data);
gtk_widget_show (item);
gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);
item = gtk_menu_item_new_with_mnemonic (_("_Paste"));
g_signal_connect (item, "activate", G_CALLBACK (paste_image), data);
gtk_widget_show (item);
gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);
gtk_menu_popup_at_pointer (GTK_MENU (menu), (GdkEvent *) event);
return TRUE;
}
GtkWidget *
do_clipboard (GtkWidget *do_widget)
{
if (!window)
{
GtkWidget *vbox, *hbox;
GtkWidget *label;
GtkWidget *entry, *button;
GtkWidget *image;
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_box_pack_start (GTK_BOX (vbox), label);
hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 4);
g_object_set (hbox, "margin", 8, NULL);
gtk_box_pack_start (GTK_BOX (vbox), hbox);
/* Create the first entry */
entry = gtk_entry_new ();
gtk_box_pack_start (GTK_BOX (hbox), entry);
/* Create the button */
button = gtk_button_new_with_mnemonic (_("_Copy"));
gtk_box_pack_start (GTK_BOX (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_box_pack_start (GTK_BOX (vbox), label);
hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 4);
g_object_set (hbox, "margin", 8, NULL);
gtk_box_pack_start (GTK_BOX (vbox), hbox);
/* Create the second entry */
entry = gtk_entry_new ();
gtk_box_pack_start (GTK_BOX (hbox), entry);
/* Create the button */
button = gtk_button_new_with_mnemonic (_("_Paste"));
gtk_box_pack_start (GTK_BOX (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_box_pack_start (GTK_BOX (vbox), label);
hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 4);
g_object_set (hbox, "margin", 8, NULL);
gtk_box_pack_start (GTK_BOX (vbox), hbox);
/* Create the first image */
image = gtk_image_new_from_icon_name ("dialog-warning");
gtk_container_add (GTK_CONTAINER (hbox), image);
/* make image a drag source */
gtk_drag_source_set (image, GDK_BUTTON1_MASK, NULL, GDK_ACTION_COPY);
gtk_drag_source_add_image_targets (image);
g_signal_connect (image, "drag-begin",
G_CALLBACK (drag_begin), image);
g_signal_connect (image, "drag-data-get",
G_CALLBACK (drag_data_get), image);
/* accept drops on image */
gtk_drag_dest_set (image, GTK_DEST_DEFAULT_ALL,
NULL, GDK_ACTION_COPY);
gtk_drag_dest_add_image_targets (image);
g_signal_connect (image, "drag-data-received",
G_CALLBACK (drag_data_received), image);
/* context menu on image */
g_signal_connect (image, "button-press-event",
G_CALLBACK (button_press), image);
/* Create the second image */
image = gtk_image_new_from_icon_name ("process-stop");
gtk_container_add (GTK_CONTAINER (hbox), image);
/* make image a drag source */
gtk_drag_source_set (image, GDK_BUTTON1_MASK, NULL, GDK_ACTION_COPY);
gtk_drag_source_add_image_targets (image);
g_signal_connect (image, "drag-begin",
G_CALLBACK (drag_begin), image);
g_signal_connect (image, "drag-data-get",
G_CALLBACK (drag_data_get), image);
/* accept drops on image */
gtk_drag_dest_set (image, GTK_DEST_DEFAULT_ALL,
NULL, GDK_ACTION_COPY);
gtk_drag_dest_add_image_targets (image);
g_signal_connect (image, "drag-data-received",
G_CALLBACK (drag_data_received), image);
/* context menu on image */
g_signal_connect (image, "button-press-event",
G_CALLBACK (button_press), image);
}
if (!gtk_widget_get_visible (window))
gtk_widget_show (window);
else
gtk_widget_destroy (window);
return window;
}