<?xml version="1.0" encoding="utf-8"?>
<page xmlns="http://projectmallard.org/1.0/" xmlns:its="http://www.w3.org/2005/11/its" xmlns:xi="http://www.w3.org/2001/XInclude" type="guide" style="task" id="messagedialog.c" xml:lang="gl">
<info>
<title type="text">MessageDialog (C)</title>
<link type="guide" xref="c#windows"/>
<link type="seealso" xref="dialog.c"/>
<revision version="0.2" date="2012-08-07" status="draft"/>
<credit type="author copyright">
<name>Monica Kochofar</name>
<email its:translate="no">monicakochofar@gmail.com</email>
<years>2012</years>
</credit>
<desc>Unha xanela de mensaxe</desc>
<mal:credit xmlns:mal="http://projectmallard.org/1.0/" type="translator copyright">
<mal:name>Fran Dieguez</mal:name>
<mal:email>frandieguez@gnome.org</mal:email>
<mal:years>2012-2013.</mal:years>
</mal:credit>
</info>
<title>MessageDialog</title>
<media type="image" mime="image/png" src="media/messagedialog.png"/>
<p>A modal message dialog which can cause the world to explode.</p>
<note><p>
To test out the application once it has started running, you can click on the "Message Dialog" tab that appears in the top menubar of the screen.
</p></note>
<code mime="text/x-csrc" style="numbered">
#include <gtk/gtk.h>
/* Callback function in which reacts to the "response" signal from the user in
* the message dialog window.
* This function is used to interact with the user in the terminal.
*/
static void
on_response (GtkDialog *dialog,
gint response_id,
gpointer user_data)
{
/* If the button clicked gives response OK (response_id being -5) */
if (response_id == GTK_RESPONSE_OK)
g_print ("*boom*\n");
/* If the button clicked gives response CANCEL (response_id being -6) */
else if (response_id == GTK_RESPONSE_CANCEL)
g_print ("good choice\n");
/* If the message dialog is destroyed (for example by pressing escape) */
else if (response_id == GTK_RESPONSE_DELETE_EVENT)
g_print ("dialog closed or cancelled\n");
/* Destroy the dialog after one of the above actions have taken place */
gtk_widget_destroy (GTK_WIDGET (dialog));
}
/* Callback function for the response signal "activate" related to the SimpleAction
* message_action.
* This function is used to cause the message dialog window to popup.
*/
static void
message_cb (GSimpleAction *simple,
GVariant *parameter,
gpointer user_data)
{
/* the parent variable in this case represents the window */
GtkWidget *message_dialog;
GtkWindow *parent = user_data;
/* Create a new message dialog, and set the parameters as follows:
* Dialog Flags - make the constructed dialog modal
* (modal windows prevent interaction with other windows in the application)
* Message Type - nonfatal warning message
* Buttons Type - use the ok and cancel buttons
* message_format - text that you want the user to see in the window
*/
message_dialog = gtk_message_dialog_new (parent, GTK_DIALOG_MODAL,
GTK_MESSAGE_WARNING,
GTK_BUTTONS_OK_CANCEL,
"This action will cause the universe to stop existing.");
gtk_widget_show_all (message_dialog);
g_signal_connect (GTK_DIALOG (message_dialog), "response",
G_CALLBACK (on_response), NULL);
}
static void
activate (GtkApplication *app,
gpointer user_data)
{
GtkWidget *window;
GtkWidget *label;
GSimpleAction *message_action;
/* Create a window with a title and a default size */
window = gtk_application_window_new (app);
gtk_window_set_title (GTK_WINDOW (window), "GMenu Example");
gtk_window_set_default_size (GTK_WINDOW (window), 400, 200);
/* Create a label and add it to the window */
label = gtk_label_new ("This application goes boom!");
gtk_container_add (GTK_CONTAINER (window), label);
/* Create a new simple action, giving it a NULL parameter type. It will
* always be NULL for actions invoked from a menu. (e.g clicking on an "ok"
* or "cancel" button)
*/
message_action = g_simple_action_new ("message", NULL);
/* Connect the "activate" signal to the appropriate callback function */
g_signal_connect (message_action, "activate", G_CALLBACK (message_cb),
GTK_WINDOW (window));
/* Adds the message_action to the overall action map. An Action map is an
* interface that contains a number of named GAction instances
* (such as message_action)
*/
g_action_map_add_action (G_ACTION_MAP (window), G_ACTION (message_action));
gtk_widget_show_all (window);
}
/* Callback function for the response signal "activate" from the "quit" action
* in the function directly below.
*/
static void
quit_cb (GSimpleAction *simple,
GVariant *parameter,
gpointer user_data)
{
GApplication *application = user_data;
g_application_quit (application);
}
/* Startup function for the menu we are creating in this sample */
static void
startup (GApplication *app,
gpointer user_data)
{
GMenu *menu;
GSimpleAction *quit_action;
/* Initialize the GMenu, and add a menu item with label "Message" and action
* "win.message". Also add another menu item with label "Quit" and action
* "app.quit"
*/
menu = g_menu_new ();
g_menu_append (menu, "Message", "win.message");
g_menu_append (menu, "Quit", "app.quit");
/* Create a new simple action for the application. (In this case it is the
* "quit" action.
*/
quit_action = g_simple_action_new ("quit", NULL);
/* Ensure that the menu we have just created is set for the overall application */
gtk_application_set_app_menu (GTK_APPLICATION (app), G_MENU_MODEL (menu));
g_signal_connect (quit_action,
"activate",
G_CALLBACK (quit_cb),
app);
g_action_map_add_action (G_ACTION_MAP (app), G_ACTION (quit_action));
}
/* Startup function for the application */
int
main (int argc, char **argv)
{
GtkApplication *app;
int status;
app = gtk_application_new ("org.gtk.example", G_APPLICATION_FLAGS_NONE);
g_signal_connect (app, "activate", G_CALLBACK (activate), NULL);
g_signal_connect (app, "startup", G_CALLBACK (startup), NULL);
status = g_application_run (G_APPLICATION (app), argc, argv);
g_object_unref (app);
return status;
}
</code>
<p>Neste exemplo empregaremos o seguinte:</p>
<list>
<item><p><link href="http://developer.gnome.org/gtk3/3.4/GtkApplication.html">GtkApplication</link></p></item>
<item><p><link href="http://developer.gnome.org/gio/stable/GApplication.html">GApplication</link></p></item>
<item><p><link href="http://developer.gnome.org/gtk3/3.4/GtkWindow.html">GtkWindow</link></p></item>
<item><p><link href="http://developer.gnome.org/gtk3/stable/GtkMessageDialog.html">GtkMessageDialog</link></p></item>
<item><p><link href="http://developer.gnome.org/gio/stable/GSimpleAction.html#g-simple-action-new">GSimpleAction</link></p></item>
<item><p><link href="http://developer.gnome.org/gio/stable/GActionMap.html">GActionMap</link></p></item>
<item><p><link href="http://developer.gnome.org/gio/stable/GMenu.html">GMenu</link></p></item>
</list>
</page>