Merge lp:~jeremywootten/slingshot/fix-1213321 into lp:slingshot

[Jeremy Wootten]

Prevents infinite loop in key_press_event handling when an input manager (ibus) is active, which appears to be due to a bug in either Gtk3 or ibus, by using an event box and custom handler rather than overriding the default handler.

Two other minor changes:
1) prevent some critical error messages when apps have no keywords.
2) prevent critical error message due to empty_cat_label not being created.

Fixes bug #1213321.

Prevents infinite loop in key_press_event handling when an input manager (ibus) is active, which appears to be due to a bug in either Gtk3 or ibus, by using an event box and custom handler rather than overriding the default handler.

Two other minor changes:
1) prevent some critical error messages when apps have no keywords.
2) prevent critical error message due to empty_cat_label not being created.

[Sergey "Shnatsel" Davidoff (shnatsel)]

I see old code is commented out but there's no explanation why. The revision control system already takes care of storing old code, so this is not needed.

I'd very much prefer the code comments to explain why this new code is needed.

[David Gomes (davidgomes)]

Very much agree with Shnatsel here. Only in rare occasions does code need to be commented, and this doesn't seem like one of those.

Besides, I approve of using the EventBox and the code style.

[Jeremy Wootten (jeremywootten)]

The reason I left the old code in was in case you wanted to revert to the
old method if and when the Gtk/ibus bug is fixed, but I can take it out. I
will also put in some comments as you suggest.

thanks for the review

On 26 August 2013 14:06, David Gomes <email address hidden> wrote:

> Very much agree with Shnatsel here. Only in rare occasions does code need
> to be commented, and this doesn't seem like one of those.
>
> Besides, I approve of using the EventBox and the code style.
> --
>
> https://code.launchpad.net/~jeremywootten/slingshot/fix-1213321/+merge/182058
> You are the owner of lp:~jeremywootten/slingshot/fix-1213321.
>

--
Jeremy Wootten
GPG Key ID CB585BCD
Key Fingerprint 37C0 3C2A A6D4 E45B BA7C 4328 2DF2 1882 CB58 5BCD

[David Gomes (davidgomes)]

https://gist.github.com/davidgomes/97279fe877acf8421fe9

Try that please.

[Jeremy Wootten (jeremywootten)]

OK, but the Elementary coding style guide says that comments should be
indented along with the code. Your example is only indented by one space.
 Is that intentional?

On 30 August 2013 09:15, David Gomes <email address hidden> wrote:

> Review: Needs Fixing
>
> https://gist.github.com/davidgomes/97279fe877acf8421fe9
>
> Try that please.
> --
>
> https://code.launchpad.net/~jeremywootten/slingshot/fix-1213321/+merge/182058
> You are the owner of lp:~jeremywootten/slingshot/fix-1213321.
>

--
Jeremy Wootten
GPG Key ID CB585BCD
Key Fingerprint 37C0 3C2A A6D4 E45B BA7C 4328 2DF2 1882 CB58 5BCD

[David Gomes (davidgomes)]

It should be the current level of indentation + 2 spaces I believe.

[Jeremy Wootten (jeremywootten)]

OK, so is this correct in this case (8 + 2 spaces indentation of comment
text)?

.
.
.
        }

        /*
          Overriding the default handler results in infinite loop of error
messages
          when an input method is in use (Gtk3 bug?). Key press events are
          captured by an Event Box and passed to this function instead.
          Events not dealt with here are propagated to the searchbar by the
          usual mechanism.
        */
        public bool on_key_press (Gdk.EventKey event) {
.
.
.
.

On 30 August 2013 19:02, David Gomes <email address hidden> wrote:

> It should be the current level of indentation + 2 spaces I believe.
> --
>
> https://code.launchpad.net/~jeremywootten/slingshot/fix-1213321/+merge/182058
> You are the owner of lp:~jeremywootten/slingshot/fix-1213321.
>

--
Jeremy Wootten
GPG Key ID CB585BCD
Key Fingerprint 37C0 3C2A A6D4 E45B BA7C 4328 2DF2 1882 CB58 5BCD

[David Gomes (davidgomes)]

+ /*Overriding the default handler results in infinite loop of error messages
+ * when an input method is in use (Gtk3 bug?). Key press events are
+ * captured by an Event Box and passed to this function instead.
+ * Events not dealt with here are propagated to the searchbar by the
+ * usual mechanism.
+ */

+ /*
+ * Overriding the default handler results in infinite loop of error messages
+ * when an input method is in use (Gtk3 bug?). Key press events are
+ * captured by an Event Box and passed to this function instead.
+
+ * Events not dealt with here are propagated to the searchbar by the
+ * usual mechanism.
+ */

I'd prefer that and then I approve. Besides, I don't want this merged without testing (both on people experiencing the bug and people who don't use ibus and never experienced the bug).

[Jeremy Wootten (jeremywootten)]

Did you want asterisks on each line? Your original suggestion did not have
them but this one does.

I agree that thorough testing by others first is advisable.

On 4 September 2013 13:27, David Gomes <email address hidden> wrote:

> Review: Needs Fixing
>
> + /*Overriding the default handler results in infinite loop of error
> messages
> + * when an input method is in use (Gtk3 bug?). Key press events are
> + * captured by an Event Box and passed to this function instead.
> + * Events not dealt with here are propagated to the searchbar by the
> + * usual mechanism.
> + */
>
> + /*
> + * Overriding the default handler results in infinite loop of error
> messages
> + * when an input method is in use (Gtk3 bug?). Key press events are
> + * captured by an Event Box and passed to this function instead.
> +
> + * Events not dealt with here are propagated to the searchbar by the
> + * usual mechanism.
> + */
>
> I'd prefer that and then I approve. Besides, I don't want this merged
> without testing (both on people experiencing the bug and people who don't
> use ibus and never experienced the bug).
> --
>
> https://code.launchpad.net/~jeremywootten/slingshot/fix-1213321/+merge/182058
> You are the owner of lp:~jeremywootten/slingshot/fix-1213321.
>

--
Jeremy Wootten
GPG Key ID CB585BCD
Key Fingerprint 37C0 3C2A A6D4 E45B BA7C 4328 2DF2 1882 CB58 5BCD

[David Gomes (davidgomes)]

Oh, shit I don't, I'm dumb sometimes:

+ /*
+ Overriding the default handler results in infinite loop of error messages
+ when an input method is in use (Gtk3 bug?). Key press events are
+ captured by an Event Box and passed to this function instead.
+
+ Events not dealt with here are propagated to the searchbar by the
+ usual mechanism.
+ */

[David Gomes (davidgomes)]

+ /*
+ Overriding the default handler results in infinite loop of error messages
+ when an input method is in use (Gtk3 bug?). Key press events are
+ captured by an Event Box and passed to this function instead.
+
+ Events not dealt with here are propagated to the searchbar by the
+ usual mechanism.
+ */

[David Gomes (davidgomes)]

Launchpad is dumb - http://pastie.org/8298305 that's what I want.

[Jeremy Wootten (jeremywootten)]

OK, done. I have also merged changes from trunk up to revision 378 and
resolved conflicts

On 4 September 2013 19:47, David Gomes <email address hidden> wrote:

> Launchpad is dumb - http://pastie.org/8298305 that's what I want.
> --
>
> https://code.launchpad.net/~jeremywootten/slingshot/fix-1213321/+merge/182058
> You are the owner of lp:~jeremywootten/slingshot/fix-1213321.
>

--
Jeremy Wootten
GPG Key ID CB585BCD
Key Fingerprint 37C0 3C2A A6D4 E45B BA7C 4328 2DF2 1882 CB58 5BCD

[David Gomes (davidgomes)]

I approve of the code now, but I believe this needs testing.

[Sergey "Shnatsel" Davidoff (shnatsel)]

I'll be running this version daily. I don't use iBus, so I'll look out for regressions.

This still needs verification from an iBus user. To test this fix, run:
sudo apt-get install elementary-testing-scripts
elementary-test-merge https://code.launchpad.net/~jeremywootten/slingshot/fix-1213321/+merge/182058

[David Gomes (davidgomes)]

It still doesn't fix focus 100% of times on Ubuntu 13.10, I think ibus is still ruining it.

Anyway, a branch got merged in this afternoon that makes it so that the Escape key hides slingshot if the search bar is empty, but clears the search bar if there's text on the search bar.

I branched trunk (lp:slingshot) and the bzr merged this branch and it breaks that new functionality.

[Sergey "Shnatsel" Davidoff (shnatsel)]

iBus is not the only thing that causes focus issues. There seems to be a race condition or something as well. There was a branch floating around that fixed it.

[Sergey "Shnatsel" Davidoff (shnatsel)]

Also, I haven't spotted any regressions against the current bzr trunk.

[David Gomes (davidgomes)]

So if you merge this with the latest trunk you can use Escape to hide Slingshot?

[Jeremy Wootten (jeremywootten)]

This branch was only intended to allow text entry into the search bar when
ibus was running. It was not intended to address the focus issues which, I
think, were pre-existing and not necessarily related to ibus. I have been
advised to keep branches "atomic".

I'll merge trunk and make sure this branch is compatible with the new
functionality.

On 10 September 2013 18:56, David Gomes <email address hidden> wrote:

> Review: Needs Fixing
>
> It still doesn't fix focus 100% of times on Ubuntu 13.10, I think ibus is
> still ruining it.
>
> Anyway, a branch got merged in this afternoon that makes it so that the
> Escape key hides slingshot if the search bar is empty, but clears the
> search bar if there's text on the search bar.
>
> I branched trunk (lp:slingshot) and the bzr merged this branch and it
> breaks that new functionality.
> --
>
> https://code.launchpad.net/~jeremywootten/slingshot/fix-1213321/+merge/182058
> You are the owner of lp:~jeremywootten/slingshot/fix-1213321.
>

--
Jeremy Wootten
GPG Key ID CB585BCD
Key Fingerprint 37C0 3C2A A6D4 E45B BA7C 4328 2DF2 1882 CB58 5BCD

[Jeremy Wootten (jeremywootten)]

I have now made the latest changes in trunk compatible with this branch
(only one line required changing). The "Escape" function did not require
changing but the "Shift-Ctrl-V" function did. Changes to the "on_key_press"
function in SlingshotView.vala in trunk could be incompatible with this
branch. In this branch "return base.key_press_event (event);" is not used
in the switch - it is replaced with "break;"

On 10 September 2013 19:37, David Gomes <email address hidden> wrote:

> So if you merge this with the latest trunk you can use Escape to hide
> Slingshot?
> --
>
> https://code.launchpad.net/~jeremywootten/slingshot/fix-1213321/+merge/182058
> You are the owner of lp:~jeremywootten/slingshot/fix-1213321.
>

--
Jeremy Wootten
GPG Key ID CB585BCD
Key Fingerprint 37C0 3C2A A6D4 E45B BA7C 4328 2DF2 1882 CB58 5BCD

[Jeremy Wootten (jeremywootten)]

Hello David

Your review of this branch is still "Needs Fixing" - I am not sure what the
outstanding problem is?

On 10 September 2013 19:37, David Gomes <email address hidden> wrote:

> So if you merge this with the latest trunk you can use Escape to hide
> Slingshot?
> --
>
> https://code.launchpad.net/~jeremywootten/slingshot/fix-1213321/+merge/182058
> You are the owner of lp:~jeremywootten/slingshot/fix-1213321.
>

--
Jeremy Wootten
GPG Key ID CB585BCD
Key Fingerprint 37C0 3C2A A6D4 E45B BA7C 4328 2DF2 1882 CB58 5BCD

[if (ifshuaishuai)]

hi,I tested this fix, and i found out it doesn't response to ENTER key, cause public bool on_key_press (Gdk.EventKey event) will never be called when only ENTER pressed

[Jeremy Wootten (jeremywootten)]

You are right! I always selected the application with the mouse so did not
notice this. I will look into this.

On 1 October 2013 08:43, if <email address hidden> wrote:

> Review: Needs Fixing
>
> hi,I tested this fix, and i found out it doesn't response to ENTER key,
> cause public bool on_key_press (Gdk.EventKey event) will never be called
> when only ENTER pressed
> --
>
> https://code.launchpad.net/~jeremywootten/slingshot/fix-1213321/+merge/182058
> You are the owner of lp:~jeremywootten/slingshot/fix-1213321.
>

--
Jeremy Wootten
GPG Key ID CB585BCD
Key Fingerprint 37C0 3C2A A6D4 E45B BA7C 4328 2DF2 1882 CB58 5BCD

[if (ifshuaishuai)]

what i did for fixing this, I'm not familiar with vala, is keep the code
handles the KP_Enter remains in the
public override bool key_press_event (Gdk.EventKey event)
{

// only deal with KP_Enter

}
and other code is exactly you fixed. I know it is bad fix, but that seems
work fine.

2013/10/2 Jeremy Wootten <email address hidden>

> You are right! I always selected the application with the mouse so did not
> notice this. I will look into this.
>
>
> On 1 October 2013 08:43, if <email address hidden> wrote:
>
> > Review: Needs Fixing
> >
> > hi,I tested this fix, and i found out it doesn't response to ENTER key,
> > cause public bool on_key_press (Gdk.EventKey event) will never be called
> > when only ENTER pressed
> > --
> >
> >
> https://code.launchpad.net/~jeremywootten/slingshot/fix-1213321/+merge/182058
> > You are the owner of lp:~jeremywootten/slingshot/fix-1213321.
> >
>
>
>
> --
> Jeremy Wootten
> GPG Key ID CB585BCD
> Key Fingerprint 37C0 3C2A A6D4 E45B BA7C 4328 2DF2 1882 CB58 5BCD
>
>
> https://code.launchpad.net/~jeremywootten/slingshot/fix-1213321/+merge/182058
> You are reviewing the proposed merge of
> lp:~jeremywootten/slingshot/fix-1213321 into lp:slingshot.
>

[Jeremy Wootten (jeremywootten)]

Thanks for this. I have uploaded a different fix already - I dealt with
the Enter key-press by connecting to the activate signal of the searchbar
instead. I am waiting to see whether anyone finds a flaw in this approach
and will bear your alternative solution in mind.

best regards

On 7 October 2013 19:36, if <email address hidden> wrote:

> what i did for fixing this, I'm not familiar with vala, is keep the code
> handles the KP_Enter remains in the
> public override bool key_press_event (Gdk.EventKey event)
> {
>
> // only deal with KP_Enter
>
> }
> and other code is exactly you fixed. I know it is bad fix, but that seems
> work fine.
>
>
> 2013/10/2 Jeremy Wootten <email address hidden>
>
> > You are right! I always selected the application with the mouse so did
> not
> > notice this. I will look into this.
> >
> >
> > On 1 October 2013 08:43, if <email address hidden> wrote:
> >
> > > Review: Needs Fixing
> > >
> > > hi,I tested this fix, and i found out it doesn't response to ENTER key,
> > > cause public bool on_key_press (Gdk.EventKey event) will never be
> called
> > > when only ENTER pressed
> > > --
> > >
> > >
> >
> https://code.launchpad.net/~jeremywootten/slingshot/fix-1213321/+merge/182058
> > > You are the owner of lp:~jeremywootten/slingshot/fix-1213321.
> > >
> >
> >
> >
> > --
> > Jeremy Wootten
> > GPG Key ID CB585BCD
> > Key Fingerprint 37C0 3C2A A6D4 E45B BA7C 4328 2DF2 1882 CB58 5BCD
> >
> >
> >
> https://code.launchpad.net/~jeremywootten/slingshot/fix-1213321/+merge/182058
> > You are reviewing the proposed merge of
> > lp:~jeremywootten/slingshot/fix-1213321 into lp:slingshot.
> >
>
> --
>
> https://code.launchpad.net/~jeremywootten/slingshot/fix-1213321/+merge/182058
> You are the owner of lp:~jeremywootten/slingshot/fix-1213321.
>

--
Jeremy Wootten
GPG Key ID CB585BCD
Key Fingerprint 37C0 3C2A A6D4 E45B BA7C 4328 2DF2 1882 CB58 5BCD

=== modified file 'src/Backend/AppSystem.vala'
--- src/Backend/AppSystem.vala	2013-06-12 21:40:32 +0000
+++ src/Backend/AppSystem.vala	2013-09-10 20:47:16 +0000
@@ -77,9 +77,9 @@
             }
 
         }
-        
+
         private void update_popularity () {
-        
+
             foreach (ArrayList<App> category in apps.values)
                 foreach (App app in category)
                     app.popularity = rl_service.get_app_popularity (app.desktop_id);
@@ -199,7 +199,7 @@
              * more priority to app.name
             **/
             string[] sorted_apps_execs = {};
-            
+
             foreach (ArrayList<App> category in apps.values) {
                 foreach (App app in category) {
                     if (!(app.exec in sorted_apps_execs)) {
@@ -219,7 +219,7 @@
                         } else if (search in app.generic_name.down ()) {
                             app.relevancy = app.generic_name.length / search.length - app.popularity;
                             filtered.add (app);
-                        }  else {
+                        }  else if (app.keywords != null) {
                             app.relevancy = 0;
                             foreach (string keyword in app.keywords) {
                                 foreach (string search_word in search.split (" ")) {

=== modified file 'src/SlingshotView.vala'
--- src/SlingshotView.vala	2013-09-10 15:01:45 +0000
+++ src/SlingshotView.vala	2013-09-10 20:47:16 +0000
@@ -52,6 +52,7 @@
         public Gtk.Grid bottom;
         public Gtk.Grid container;
         public Gtk.Box content_area;
+        private Gtk.EventBox event_box;
 
         public AppSystem app_system;
         private ArrayList<TreeDirectory> categories;
@@ -215,9 +216,11 @@
             container.attach (Utils.set_padding (center, 0, 12, 12, 12), 0, 1, 1, 1);
             container.attach (Utils.set_padding (bottom, 0, 24, 12, 24), 0, 2, 1, 1);
 
+            event_box = new Gtk.EventBox ();
+            event_box.add (container);
             // Add the container to the dialog's content area
             content_area = get_content_area () as Box;
-            content_area.pack_start (container);
+            content_area.pack_start (event_box);
 
             if (Slingshot.settings.use_category)
                 set_modality (Modality.CATEGORY_VIEW);
@@ -236,6 +239,7 @@
 
             //view_manager.draw.connect (this.draw_background);
 
+            event_box.key_press_event.connect (on_key_press);
             searchbar.text_changed_pause.connect ((text) => this.search (text));
             searchbar.grab_focus ();
 
@@ -246,7 +250,7 @@
             populate_grid_view ();
 
             page_switcher.active_changed.connect (() => {
-            
+
                 move_page (page_switcher.active - page_switcher.old_active);
                 searchbar.grab_focus (); //avoid focus is not on current page
             });
@@ -284,7 +288,7 @@
         private void reposition (bool show=true) {
 
             debug("Repositioning");
-            
+
             Gdk.Rectangle monitor_dimensions, app_launcher_pos;
             screen.get_monitor_geometry (this.screen.get_primary_monitor(), out monitor_dimensions);
             app_launcher_pos = Gdk.Rectangle () { x = monitor_dimensions.x,
@@ -306,8 +310,15 @@
             }
         }
 
-        public override bool key_press_event (Gdk.EventKey event) {
+        /*
+          Overriding the default handler results in infinite loop of error messages
+          when an input method is in use (Gtk3 bug?).  Key press events are
+          captured by an Event Box and passed to this function instead.
 
+          Events not dealt with here are propagated to the searchbar by the
+          usual mechanism.
+        */
+        public bool on_key_press (Gdk.EventKey event) {
             var key = Gdk.keyval_name (event.keyval).replace ("KP_", "");
 
             event.state &= (Gdk.ModifierType.SHIFT_MASK |
@@ -347,7 +358,7 @@
                 case "Alt_L":
                 case "Alt_R":
                     break;
-                
+
                 case "0":
                 case "1":
                 case "2":
@@ -357,12 +368,12 @@
                 case "6":
                 case "7":
                 case "8":
-                case "9":          
+                case "9":
                     int page = int.parse (key) - 1;
-                
-                    if (event.state != Gdk.ModifierType.MOD1_MASK) 
-                        return base.key_press_event (event);
-                        
+
+                    if (event.state != Gdk.ModifierType.MOD1_MASK)
+                        return false;
+
                     if (modality == Modality.NORMAL_VIEW) {
                         if (page < 0 || page == 8)
                             page_switcher.set_active (grid_view.get_n_pages () - 1);
@@ -374,7 +385,7 @@
                         else
                             category_view.switcher.set_active (page);
                     } else {
-                        return base.key_press_event (event);
+                        return false;
                     }
                     searchbar.grab_focus ();
                     break;
@@ -392,7 +403,7 @@
                             new_focus.grab_focus ();
                     }
                     break;
-                
+
                 case "Left":
                     if (modality == Modality.NORMAL_VIEW) {
                         if (event.state == Gdk.ModifierType.SHIFT_MASK) // Shift + Left
@@ -406,9 +417,9 @@
                             category_move_focus (-1, 0);
                         }
                     } else
-                        return base.key_press_event (event);
+                        return false;
                     break;
-                
+
                 case "Right":
                     if (modality == Modality.NORMAL_VIEW) {
                         if (event.state == Gdk.ModifierType.SHIFT_MASK) // Shift + Right
@@ -423,10 +434,10 @@
                         else //the user has already selected an AppEntry
                             category_move_focus (+1, 0);
                     } else {
-                        return base.key_press_event (event);
+                        return false;
                     }
                     break;
-                
+
                 case "Up":
                     if (modality == Modality.NORMAL_VIEW) {
                             normal_move_focus (0, -1);
@@ -492,17 +503,17 @@
                     if (event.state == Gdk.ModifierType.SHIFT_MASK) { // Shift + Delete
                         searchbar.text = "";
                     } else if (searchbar.has_focus) {
-                        return base.key_press_event (event);
+                        return false;
                     } else {
                         searchbar.grab_focus ();
                         searchbar.move_cursor (Gtk.MovementStep.BUFFER_ENDS, 0, false);
-                        return base.key_press_event (event);
+                        return false;
                     }
                     break;
-                
+
                 case "Home":
                     if (searchbar.text.size () > 0) {
-                        return base.key_press_event (event);
+                        return false;
                     }
 
                     if (modality == Modality.NORMAL_VIEW) {
@@ -512,10 +523,10 @@
                         top_left_focus ();
                     }
                     break;
-                
+
                 case "End":
                     if (searchbar.text.size () > 0) {
-                        return base.key_press_event (event);
+                        return false;
                     }
 
                     if (modality == Modality.NORMAL_VIEW) {
@@ -531,15 +542,14 @@
                     if ((event.state & (Gdk.ModifierType.CONTROL_MASK | Gdk.ModifierType.SHIFT_MASK)) != 0) {
                         searchbar.paste_clipboard ();
                     }
-
-                    return base.key_press_event (event);
+                    break;
 
                 default:
                     if (!searchbar.has_focus) {
                         searchbar.grab_focus ();
                         searchbar.move_cursor (Gtk.MovementStep.BUFFER_ENDS, 0, false);
                     }
-                    return base.key_press_event (event);
+                    return false;
 
             }
 
@@ -595,19 +605,19 @@
             Wnck.Screen.get_default ().force_update ();
             if (w != null)
                 w.activate (Gdk.x11_get_server_time (this.get_window ()));
-		}
+        }
 
         private void move_page (int step) {
-        
+
             debug ("Moving: step = " + step.to_string ());
-        
+
             if (step == 0)
                 return;
             if (step < 0 && current_position >= 0) //Left border
                 return;
             if (step > 0 && (-current_position) >= ((grid_view.get_n_pages () - 1) * grid_view.get_page_columns () * 130)) //Right border
                 return;
-            
+
             int count = 0;
             int increment = -step * 130 * columns / 10;
             Timeout.add (30 / columns, () => {
@@ -617,12 +627,12 @@
                     view_manager.move (grid_view, current_position, 0);
                     return false;
                 }
-                    
+
                 current_position += increment;
                 view_manager.move (grid_view, current_position, 0);
                 count++;
                 return true;
-                
+
             }, Priority.DEFAULT_IDLE);
         }
 
@@ -723,13 +733,13 @@
             search_view_position = 0;
             view_manager.move (search_view, 0, search_view_position);
             search_view.hide_all ();
-            
+
             var filtered = yield app_system.search_results (stripped);
 
             foreach (App app in filtered) {
                 search_view.show_app (app);
             }
-            
+
             search_view.add_command (text);
 
         }
@@ -749,7 +759,7 @@
                 grid_view.append (app_entry);
                 app_entry.show_all ();
             }
-                            
+
             view_manager.move (grid_view, 0, 0);
             current_position = 0;
 

=== modified file 'src/Widgets/CategoryView.vala'
--- src/Widgets/CategoryView.vala	2013-02-22 17:17:35 +0000
+++ src/Widgets/CategoryView.vala	2013-09-10 20:47:16 +0000
@@ -64,6 +64,7 @@
 
             app_view = new Widgets.Grid (view.rows, view.columns - 1);
             layout.put (app_view, 0, 0);
+            empty_cat_label = new Gtk.Label ("");
             layout.put (empty_cat_label, view.columns*130, view.rows * 130 / 2);
             layout.set_hexpand (true);
             layout.set_vexpand (true);
@@ -133,7 +134,7 @@
             });
 
             app_view.new_page.connect ((page) => {
-                
+
                 if (switcher.size == 0)
                     switcher.append ("1");
                 switcher.append (page);
@@ -151,7 +152,7 @@
                 move_page (switcher.active - switcher.old_active);
                 view.searchbar.grab_focus (); // this is because otherwise focus isn't the current page
             });
-            
+
             category_switcher.selected = 0; //Must be after everything else
         }
 
@@ -168,11 +169,11 @@
 
             switcher.clear_children ();
             app_view.clear ();
-            
+
             layout.move (empty_cat_label, view.columns*130, view.rows*130 / 2);
             foreach (App app in view.apps[category])
-	            add_app (app);
-            
+                add_app (app);
+
             switcher.set_active (0);
 
             layout.move (app_view, 0, 0);
@@ -181,16 +182,16 @@
         }
 
         public void move_page (int step) {
-        
+
             debug ("Moving: step = " + step.to_string ());
-        
+
             if (step == 0)
                 return;
             if (step < 0 && current_position >= 0) //Left border
                 return;
             if (step > 0 && (-current_position) >= ((app_view.get_n_pages () - 1) * app_view.get_page_columns () * 130)) //Right border
                 return;
-            
+
             int count = 0;
             int increment = -step*130*(view.columns-1)/10;
             Timeout.add (30/(view.columns-1), () => {
@@ -200,12 +201,12 @@
                     layout.move (app_view, current_position, 0);
                     return false;
                 }
-                    
+
                 current_position += increment;
                 layout.move (app_view, current_position, 0);
                 count++;
                 return true;
-                
+
             }, Priority.DEFAULT_IDLE);
         }
 
@@ -220,7 +221,7 @@
             }
             else
                 page_switcher.hide ();
-                
+
             view.searchbar.grab_focus ();
 
         }