Make File-Picker modal on Linux

chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc

Index: chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc
diff --git a/chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc b/chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc
index 95f9a448378e6fb26e64a904fa3117dfbd12a730..828321ba19ad708e95345bb8275865b74b80e1e3 100644
--- a/chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc
+++ b/chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.cc
@@ -4,6 +4,7 @@
 
 #include "chrome/browser/ui/libgtk2ui/select_file_dialog_impl_gtk2.h"
 
+#include <gdk/gdkx.h>
 #include <gtk/gtk.h>
 #include <stddef.h>
 #include <sys/stat.h>
@@ -32,6 +33,7 @@
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/shell_dialogs/select_file_dialog.h"
 #include "ui/strings/grit/ui_strings.h"
+#include "ui/views/widget/desktop_aura/desktop_window_tree_host_x11.h"
 #include "ui/views/widget/desktop_aura/x11_desktop_handler.h"
 
 namespace {
@@ -48,6 +50,13 @@ void OnFileFilterDataDestroyed(std::string* file_extension) {
   delete file_extension;
 }
 
+// Runs DesktopWindowTreeHostX11::EnableEventListening() by calling the
+// destructor of ScopedHandle class when the file-picker is closed.
+void OnFilePickerDestroy(views::DesktopWindowTreeHostX11::ScopedHandle*
+    scoped_handle) {
+  delete scoped_handle;
+}
+
 }  // namespace
 
 namespace libgtk2ui {
@@ -164,10 +173,16 @@ void SelectFileDialogImplGTK::SelectFileImpl(
 
   params_map_[dialog] = params;
 
-  // TODO(erg): Figure out how to fake GTK window-to-parent modality without
-  // having the parent be a real GtkWindow.
-  gtk_window_set_modal(GTK_WINDOW(dialog), TRUE);
-
+  // Disable input events handling in the host window to make this dialog modal.
+  views::DesktopWindowTreeHostX11* host =
+      views::DesktopWindowTreeHostX11::GetHostForXID(
+      owning_window->GetHost()->GetAcceleratedWidget());

[sadrul, 2016/04/19 14:56:11]

owning_window can be null, right? (see code/comment above)

[joone, 2016/04/19 22:29:56]

I tried to reproduce the bug, but the file-picker is shown up well without any
crash. I think this bug was already fixed.

[sadrul, 2016/05/11 05:27:47]

Update the code/comment from above too (lines 128:134). It should probably be a
separate CL that lands first.

[joone, 2016/05/11 19:18:05]

I already did it: https://codereview.chromium.org/1912873002

+  std::unique_ptr<views::DesktopWindowTreeHostX11::ScopedHandle> scoped_handle =
+      host->DisableEventListening(
+          GDK_WINDOW_XID(gtk_widget_get_window(dialog)));
+  g_object_set_data_full(G_OBJECT(dialog), "scoped_handle",
+      scoped_handle.release(),
+      reinterpret_cast<GDestroyNotify>(OnFilePickerDestroy));

[sadrul, 2016/04/19 14:56:11]

Add a comment here:

  // OnFilePickerDestroy() is called when |dialog| destroyed. The
  // callback destroys the ScopedHandle instance, this re-enabling
  // events on the owning window.

   gtk_widget_show_all(dialog);
 
   // We need to call gtk_window_present after making the widgets visible to make