[gtk/show-uri-async: 1/2] Redo gtk_show_uri_on_window

[Matthias Clasen <matthiasc src gnome org>]

commit 703f18ce660a6020ccc6164c6ac5e19b0d7f71db
Author: Matthias Clasen <mclasen redhat com>
Date:   Sat Apr 11 21:56:32 2020 -0400

    Redo gtk_show_uri_on_window
    
    Make this a full async function, and add a simple wrapper.
    
    Call gtk_show_uri_full() if you need control over the
    results, and use gtk_show_uri() if you are fine with
    ignoring any errors.

 docs/reference/gtk/gtk4-sections.txt |   4 +-
 gtk/gtkshow.c                        | 186 ++++++++++++++++++++++++++++-------
 gtk/gtkshow.h                        |  20 +++-
 3 files changed, 167 insertions(+), 43 deletions(-)
---
diff --git a/docs/reference/gtk/gtk4-sections.txt b/docs/reference/gtk/gtk4-sections.txt
index 338ea2b06a..7638136709 100644
--- a/docs/reference/gtk/gtk4-sections.txt
+++ b/docs/reference/gtk/gtk4-sections.txt
@@ -5105,7 +5105,9 @@ gtk_mount_operation_set_parent
 gtk_mount_operation_get_parent
 gtk_mount_operation_set_display
 gtk_mount_operation_get_display
-gtk_show_uri_on_window
+gtk_show_uri_full
+gtk_show_uri_full_finish
+gtk_show_uri
 <SUBSECTION Standard>
 GTK_IS_MOUNT_OPERATION
 GTK_IS_MOUNT_OPERATION_CLASS
diff --git a/gtk/gtkshow.c b/gtk/gtkshow.c
index ee9ae82cfb..2163b120a1 100644
--- a/gtk/gtkshow.c
+++ b/gtk/gtkshow.c
@@ -24,73 +24,102 @@
 
 #include "gtkshow.h"
 #include "gtkwindowprivate.h"
+#include "gtkmessagedialog.h"
+#include "gtkintl.h"
+
+typedef struct {
+  GtkWindow *parent;
+  GAppLaunchContext *context;
+  char *uri;
+  GTask *task;
+} GtkShowUriData;
+
+static void
+gtk_show_uri_data_free (GtkShowUriData *data)
+{
+  if (data->parent)
+    gtk_window_unexport_handle (data->parent);
+  g_clear_object (&data->parent);
+  g_clear_object (&data->context);
+  g_free (data->uri);
+  g_clear_object (&data->task);
+  g_free (data);
+}
 
 static void
 launch_uri_done (GObject      *source,
                  GAsyncResult *result,
-                 gpointer      data)
+                 gpointer      user_data)
 {
-  GtkWindow *window = data;
+  GtkShowUriData *data = user_data;
+  GError *error = NULL;
 
-  g_app_info_launch_default_for_uri_finish (result, NULL);
+  if (g_app_info_launch_default_for_uri_finish (result, &error))
+    g_task_return_boolean (data->task, TRUE);
+  else
+    g_task_return_error (data->task, error);
 
-  if (window)
-    gtk_window_unexport_handle (window);
+  gtk_show_uri_data_free (data);
 }
 
 static void
 window_handle_exported (GtkWindow  *window,
-                        const char *handle_str,
+                        const char *handle,
                         gpointer    user_data)
 {
-  GAppLaunchContext *context = user_data;
-  const char *uri;
-
-  uri = (const char *)g_object_get_data (G_OBJECT (context), "uri");
-
-  g_app_launch_context_setenv (context, "PARENT_WINDOW_ID", handle_str);
+  GtkShowUriData *data = user_data;
 
-  g_app_info_launch_default_for_uri_async (uri, G_APP_LAUNCH_CONTEXT (context), NULL, launch_uri_done, 
window);
+  if (handle)
+    g_app_launch_context_setenv (data->context, "PARENT_WINDOW_ID", handle);
 
-  g_object_unref (context);
+  g_app_info_launch_default_for_uri_async (data->uri,
+                                           data->context,
+                                           g_task_get_cancellable (data->task),
+                                           launch_uri_done,
+                                           data);
 }
 
 /**
- * gtk_show_uri_on_window:
+ * gtk_show_uri_full:
  * @parent: (allow-none): parent window
  * @uri: the uri to show
- * @timestamp: a timestamp to prevent focus stealing
- * @error: a #GError that is returned in case of errors
+ * @timestamp: timestamp from the event that triggered this call, or %GDK_CURRENT_TIME
+ * @cancellable: (allow-none): a #GCancellable to cancel the launch
+ * @callback (allow-none): a callback to call when the action is complete
+ * @user_data: data to pass to @callback
+ * @destroy: destroy notify for @user_data
  *
- * This is a convenience function for launching the default application
- * to show the uri. The uri must be of a form understood by GIO (i.e. you
- * need to install gvfs to get support for uri schemes such as http://
+ * This function launches the default application for showing
+ * a given uri.
+ *
+ * The uri must be of a form understood by GIO (i.e. you need
+ * to install gvfs to get support for uri schemes such as http://
  * or ftp://, as only local files are handled by GIO itself).
  * Typical examples are
  * - `file:///home/gnome/pict.jpg`
  * - `http://www.gnome.org`
  * - `mailto:me gnome org`
  *
- * Ideally the timestamp is taken from the event triggering
- * the gtk_show_uri_on_window() call. If timestamp is not known you can take
- * %GDK_CURRENT_TIME.
+ * The @callback will be called when the launch is completed.
+ * It should call gtk_show_uri_finish() to obtain the result.
  *
  * This is the recommended call to be used as it passes information
  * necessary for sandbox helpers to parent their dialogs properly.
- *
- * Returns: %TRUE on success, %FALSE on error
  */
-gboolean
-gtk_show_uri_on_window (GtkWindow   *parent,
-                        const char  *uri,
-                        guint32      timestamp,
-                        GError     **error)
+void
+gtk_show_uri_full (GtkWindow           *parent,
+                   const char          *uri,
+                   guint32              timestamp,
+                   GCancellable        *cancellable,
+                   GAsyncReadyCallback  callback,
+                   gpointer             user_data)
 {
+  GtkShowUriData *data;
   GdkAppLaunchContext *context;
-  gboolean ret;
   GdkDisplay *display;
 
-  g_return_val_if_fail (uri != NULL, FALSE);
+  g_return_if_fail (parent == NULL || GTK_IS_WINDOW (parent));
+  g_return_if_fail (uri != NULL);
 
   if (parent)
     display = gtk_widget_get_display (GTK_WIDGET (parent));
@@ -100,13 +129,94 @@ gtk_show_uri_on_window (GtkWindow   *parent,
   context = gdk_display_get_app_launch_context (display);
   gdk_app_launch_context_set_timestamp (context, timestamp);
 
-  g_object_set_data_full (G_OBJECT (context), "uri", g_strdup (uri), g_free);
+  data = g_new0 (GtkShowUriData, 1);
+  data->parent = parent ? g_object_ref (parent) : NULL;
+  data->context = G_APP_LAUNCH_CONTEXT (context);
+  data->uri = g_strdup (uri);
+  data->task = g_task_new (parent, cancellable, callback, user_data);
+  g_task_set_source_tag (data->task, gtk_show_uri);
+
+  if (parent)
+    gtk_window_export_handle (parent, window_handle_exported, data);
+  else
+    window_handle_exported (parent, NULL, data);
+}
+
+/**
+ * gtk_show_uri_full_finish:
+ * @parent: the #GtkWindow passed to gtk_show_uri()
+ * @result: #GASyncResult that was passed to @callback
+ * @error: return location for an error
+ *
+ * Finished the gtk_show_uri() call and returns the result
+ * of the operation.
+ *
+ * Returns: %TRUE if the URI was shown successfully.
+ *     Otherwise, %FALSE is returned and @error is set
+ */
+gboolean
+gtk_show_uri_full_finish (GtkWindow     *parent,
+                          GAsyncResult  *result,
+                          GError       **error)
+{
+  g_return_val_if_fail (parent == NULL || GTK_IS_WINDOW (parent), FALSE);
+  g_return_val_if_fail (g_task_is_valid (result, parent), FALSE);
+  g_return_val_if_fail (g_task_get_source_tag (G_TASK (result)) == gtk_show_uri, FALSE);
 
-  if (parent && gtk_window_export_handle (parent, window_handle_exported, context))
-    return TRUE;
+  return g_task_propagate_boolean (G_TASK (result), error);
+}
 
-  ret = g_app_info_launch_default_for_uri (uri, G_APP_LAUNCH_CONTEXT (context), error);
-  g_object_unref (context);
+static void
+show_uri_done (GObject      *object,
+               GAsyncResult *result,
+               gpointer      data)
+{
+  GtkWindow *parent = GTK_WINDOW (object);
+  GError *error = NULL;
+
+  if (!gtk_show_uri_full_finish (parent, result, &error))
+    {
+      GtkWidget *dialog;
+
+      dialog = gtk_message_dialog_new (parent,
+                                       GTK_DIALOG_DESTROY_WITH_PARENT |
+                                       GTK_DIALOG_MODAL,
+                                       GTK_MESSAGE_ERROR,
+                                       GTK_BUTTONS_CLOSE,
+                                       "%s", _("Could not show link"));
+      gtk_message_dialog_format_secondary_text (GTK_MESSAGE_DIALOG (dialog),
+                                                "%s", error->message);
+
+      g_signal_connect (dialog, "response",
+                        G_CALLBACK (gtk_widget_destroy), NULL);
+
+      G_GNUC_BEGIN_IGNORE_DEPRECATIONS
+      gtk_window_present (GTK_WINDOW (dialog));
+      G_GNUC_END_IGNORE_DEPRECATIONS
+    }
+}
 
-  return ret;
+/**
+ * gtk_show_uri:
+ * @parent: (allow-none): parent window
+ * @uri: the uri to show
+ * @timestamp: timestamp from the event that triggered this call, or %GDK_CURRENT_TIME
+ *
+ * This function launches the default application for showing
+ * a given uri, or shows an error dialog if that fails.
+ *
+ * The uri must be of a form understood by GIO (i.e. you need
+ * to install gvfs to get support for uri schemes such as http://
+ * or ftp://, as only local files are handled by GIO itself).
+ * Typical examples are
+ * - `file:///home/gnome/pict.jpg`
+ * - `http://www.gnome.org`
+ * - `mailto:me gnome org`
+ */
+void
+gtk_show_uri (GtkWindow  *parent,
+              const char *uri,
+              guint32     timestamp)
+{
+  gtk_show_uri_full (parent, uri, timestamp, NULL, show_uri_done, NULL);
 }
diff --git a/gtk/gtkshow.h b/gtk/gtkshow.h
index ac187ff079..0c5cea6fba 100644
--- a/gtk/gtkshow.h
+++ b/gtk/gtkshow.h
@@ -30,10 +30,22 @@
 G_BEGIN_DECLS
 
 GDK_AVAILABLE_IN_ALL
-gboolean gtk_show_uri_on_window (GtkWindow   *parent,
-                                 const char  *uri,
-                                 guint32      timestamp,
-                                 GError     **error);
+void gtk_show_uri_full (GtkWindow           *parent,
+                        const char          *uri,
+                        guint32              timestamp,
+                        GCancellable        *cancellable,
+                        GAsyncReadyCallback  callback,
+                        gpointer             user_data);
+
+GDK_AVAILABLE_IN_ALL
+gboolean gtk_show_uri_full_finish (GtkWindow     *parent,
+                                   GAsyncResult  *result,
+                                   GError       **error);
+
+GDK_AVAILABLE_IN_ALL
+void gtk_show_uri (GtkWindow  *parent,
+                   const char *uri,
+                   guint32     timestamp);
 
 G_END_DECLS