[gnome-shell/issue-23: 42/43] switcherPopup: Handle removal of items from SwitcherPopup

[Mario Sanchez Prada <msanchez src gnome org>]

commit 9957f7675633acb19e1d2d7de8da2acccf846e6a
Author: Mario Sanchez Prada <mario endlessm com>
Date:   Thu Feb 8 11:11:11 2018 +0000

    switcherPopup: Handle removal of items from SwitcherPopup
    
    This will be mainly useful for closing apps from the applications
    switcher, but can be implemented generically enough to select the
    nearest existing item after removal if there's any, or destroying
    the popup's actor otherwise.
    
    Specifically for the apps switcher, doing this also removes the need
    of having to manually either update the current app in AppSwitcher
    and highlight it, if there are still any items after the removal, or
    simply destroy the AppSwitcher otherwise. Besides, calling _select()
    in the handler for item-removed makes sure that the list of thumbnails
    in the switcher is always closed, if open, when quitting the app.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=620106

 js/ui/altTab.js        |  7 -------
 js/ui/switcherPopup.js | 25 ++++++++++++++++++++-----
 2 files changed, 20 insertions(+), 12 deletions(-)
---
diff --git a/js/ui/altTab.js b/js/ui/altTab.js
index 80039cba5..407a56e4c 100644
--- a/js/ui/altTab.js
+++ b/js/ui/altTab.js
@@ -812,13 +812,6 @@ var AppSwitcher = new Lang.Class({
 
         this.icons.splice(index, 1);
         this.removeItem(index);
-
-        if (this._curApp == index)
-            this._curApp = SwitcherPopup.mod(index, this.icons.length);
-        if (this.icons.length > 0)
-            this.highlight(this._curApp);
-        else
-            this.actor.destroy();
     },
 });
 
diff --git a/js/ui/switcherPopup.js b/js/ui/switcherPopup.js
index 9a29ce2c2..9f92c4598 100644
--- a/js/ui/switcherPopup.js
+++ b/js/ui/switcherPopup.js
@@ -133,6 +133,7 @@ var SwitcherPopup = new Lang.Class({
         this.actor.add_actor(this._switcherList.actor);
         this._switcherList.connect('item-activated', Lang.bind(this, this._itemActivated));
         this._switcherList.connect('item-entered', Lang.bind(this, this._itemEntered));
+        this._switcherList.connect('item-removed', Lang.bind(this, this._itemRemoved));
 
         // Need to force an allocation so we can figure out whether we
         // need to scroll when selecting
@@ -247,6 +248,19 @@ var SwitcherPopup = new Lang.Class({
         this._itemEnteredHandler(n);
     },
 
+    _itemRemovedHandler: function(n) {
+        if (this._items.length > 0) {
+            let newIndex = Math.min(n, this._items.length - 1);
+            this._select(newIndex);
+        } else {
+            this.actor.destroy();
+        }
+    },
+
+    _itemRemoved: function(switcher, n) {
+        this._itemRemovedHandler(n);
+    },
+
     _disableHover: function() {
         this.mouseActive = false;
 
@@ -421,6 +435,7 @@ var SwitcherList = new Lang.Class({
     removeItem: function(index) {
         let item = this._items.splice(index, 1);
         item[0].destroy();
+        this.emit('item-removed', index);
     },
 
     _onItemClicked: function (index) {
@@ -442,15 +457,15 @@ var SwitcherList = new Lang.Class({
             this._items[this._highlighted].remove_style_pseudo_class('selected');
         }
 
-        this._highlighted = index;
-
-        if (this._highlighted != -1) {
+        if (this._items[index]) {
             if (justOutline)
-                this._items[this._highlighted].add_style_pseudo_class('outlined');
+                this._items[index].add_style_pseudo_class('outlined');
             else
-                this._items[this._highlighted].add_style_pseudo_class('selected');
+                this._items[index].add_style_pseudo_class('selected');
         }
 
+        this._highlighted = index;
+
         let adjustment = this._scrollView.hscroll.adjustment;
         let [value, lower, upper, stepIncrement, pageIncrement, pageSize] = adjustment.get_values();
         let [absItemX, absItemY] = this._items[index].get_transformed_position();