diff --git a/demos/gtk-demo/demo.gresource.xml b/demos/gtk-demo/demo.gresource.xml index 9cd5057a2a..8a0bedf729 100644 --- a/demos/gtk-demo/demo.gresource.xml +++ b/demos/gtk-demo/demo.gresource.xml @@ -210,6 +210,7 @@ infobar.c links.c listbox.c + listview_applauncher.c listview_filebrowser.c listview_minesweeper.c listview_settings.c diff --git a/demos/gtk-demo/listview_applauncher.c b/demos/gtk-demo/listview_applauncher.c new file mode 100644 index 0000000000..1a1c33f86f --- /dev/null +++ b/demos/gtk-demo/listview_applauncher.c @@ -0,0 +1,200 @@ +/* Lists/Application launcher + * + * This demo uses the GtkCoverFlow widget as a fancy application launcher. + * + * It is also a very small introduction to listviews. + */ + +#include + +/* This is the function that creates the #GListModel that we need. + * GTK list widgets need a #GListModel to display, as models support change + * notifications. + * Unfortunately various older APIs do not provide list models, so we create + * our own. + */ +static GListModel * +create_application_list (void) +{ + GListStore *store; + GList *apps, *l; + + /* We use a #GListStore here, which is a simple array-like list implementation + * for manual management. + * List models need to know what type of data they provide, so we need to + * provide the type here. As we want to do a list of applications, #GAppInfo + * is the object we provide. + */ + store = g_list_store_new (G_TYPE_APP_INFO); + + apps = g_app_info_get_all (); + + for (l = apps; l; l = l->next) + { + g_list_store_append (store, l->data); + } + + g_list_free_full (apps, g_object_unref); + + return G_LIST_MODEL (store); +} + +/* This is the function we use for setting up new listitems to display. + * We add just a #GtkImage here to display the application's icon as this is just + * a simple demo. + */ +static void +setup_listitem_cb (GtkListItemFactory *factory, + GtkListItem *list_item) +{ + GtkWidget *image; + + image = gtk_image_new (); + gtk_image_set_icon_size (GTK_IMAGE (image), GTK_ICON_SIZE_LARGE); + + gtk_list_item_set_child (list_item, image); +} + +/* Here we need to prepare the listitem for displaying its item. We get the + * listitem already set up from the previous function, so we can reuse the + * #GtkImage widget we set up above. + * We get the item - which we know is a #GAppInfo because it comes out of + * the model we set up above, grab its icon and display it. + */ +static void +bind_listitem_cb (GtkListItemFactory *factory, + GtkListItem *list_item) +{ + GtkWidget *image; + GAppInfo *app_info; + + image = gtk_list_item_get_child (list_item); + app_info = gtk_list_item_get_item (list_item); + + gtk_image_set_from_gicon (GTK_IMAGE (image), g_app_info_get_icon (app_info)); +} + +/* In more complex code, we would also need functions to unbind and teardown + * the listitem, but this is simple code, so the default implementations are + * enough. If we had connected signals, this step would have been necessary. + * + * The #GtkSignalListItemFactory documentation contains more information about + * this step. + */ + +/* This function is called whenever an item in the list is activated. This is + * the simple way to allow reacting to the Enter key or double-clicking on a + * listitem. + * Of course, it is possible to use far more complex interactions by turning + * off activation and adding buttons or other widgets in the setup function + * above, but this is a simple demo, so we'll use the simple way. + */ +static void +activate_cb (GtkCoverFlow *coverflow, + guint position, + gpointer unused) +{ + GAppInfo *app_info; + GdkAppLaunchContext *context; + GError *error = NULL; + + app_info = g_list_model_get_item (gtk_cover_flow_get_model (coverflow), position); + + /* Prepare the context for launching the application and launch it. This + * code is explained in detail in the documentation for #GdkAppLaunchContext + * and #GAppInfo. + */ + context = gdk_display_get_app_launch_context (gtk_widget_get_display (GTK_WIDGET (coverflow))); + if (!g_app_info_launch (app_info, + NULL, + G_APP_LAUNCH_CONTEXT (context), + &error)) + { + GtkWidget *dialog; + + /* And because error handling is important, even a simple demo has it: + * We display an error dialog that something went wrong. + */ + dialog = gtk_message_dialog_new (GTK_WINDOW (gtk_widget_get_root (GTK_WIDGET (coverflow))), + GTK_DIALOG_DESTROY_WITH_PARENT | GTK_DIALOG_MODAL, + GTK_MESSAGE_ERROR, + GTK_BUTTONS_CLOSE, + "Could not launch %s", g_app_info_get_display_name (app_info)); + gtk_message_dialog_format_secondary_text (GTK_MESSAGE_DIALOG (dialog), "%s", error->message); + g_clear_error (&error); + gtk_widget_show (dialog); + } + + g_object_unref (context); + g_object_unref (app_info); +} + +static GtkWidget *window = NULL; + +GtkWidget * +do_listview_applauncher (GtkWidget *do_widget) +{ + if (window == NULL) + { + GtkWidget *coverflow, *sw;; + GListModel *model; + GtkListItemFactory *factory; + + /* Create a window and set a few defaults */ + window = gtk_window_new (GTK_WINDOW_TOPLEVEL); + gtk_window_set_default_size (GTK_WINDOW (window), 640, 320); + gtk_window_set_display (GTK_WINDOW (window), + gtk_widget_get_display (do_widget)); + gtk_window_set_title (GTK_WINDOW (window), "Application Launcher"); + g_signal_connect (window, "destroy", + G_CALLBACK(gtk_widget_destroyed), &window); + + /* The #GtkListitemFactory is what is used to create #GtkListItems + * to display the data from the model. So it is absolutely necessary + * to create one. + * We will use a #GtkSignalListItemFactory because it is the simplest + * one to use. Different ones are available for different use cases. + * The most powerful one is #GtkBuilderListItemFactory which uses + * #GtkBuilder .ui files, so it requires little code. + */ + factory = gtk_signal_list_item_factory_new (); + g_signal_connect (factory, "setup", G_CALLBACK (setup_listitem_cb), NULL); + g_signal_connect (factory, "bind", G_CALLBACK (bind_listitem_cb), NULL); + + /* Create the list widget here: We use a coverflow widget because it's + * the coolest one. We could just as well use other list widgets such + * as a #GtkListView or a #GtkGridView and the code would look very + * similar. + */ + coverflow = gtk_cover_flow_new_with_factory (factory); + /* We connect the activate signal here. It's the function we defined + * above for launching the selected application. + */ + g_signal_connect (coverflow, "activate", G_CALLBACK (activate_cb), NULL); + + /* And of course we need to set the data model. Here we call the function + * we wrote above that gives us the list of applications. Then we set + * it on the coverflow list widget. + * The coverflow will now take items from the model and use the factory + * to create as many listitems as it needs to show itself to the user. + */ + model = create_application_list (); + gtk_cover_flow_set_model (GTK_COVER_FLOW (coverflow), model); + g_object_unref (model); + + /* List widgets should always be contained in a #GtkScrolledWindow, + * because otherwise they might get too large or they might not + * be scrollable. + */ + sw = gtk_scrolled_window_new (NULL, NULL); + gtk_container_add (GTK_CONTAINER (window), sw); + gtk_container_add (GTK_CONTAINER (sw), coverflow); + } + + if (!gtk_widget_get_visible (window)) + gtk_widget_show (window); + else + gtk_widget_destroy (window); + + return window; +} diff --git a/demos/gtk-demo/meson.build b/demos/gtk-demo/meson.build index 9b926209e4..4b1cc3ec73 100644 --- a/demos/gtk-demo/meson.build +++ b/demos/gtk-demo/meson.build @@ -44,6 +44,7 @@ demos = files([ 'listbox.c', 'flowbox.c', 'list_store.c', + 'listview_applauncher.c', 'listview_filebrowser.c', 'listview_minesweeper.c', 'listview_settings.c',