[gnome-shell/gbsneto/icon-grid-part2: 7/10] allView: Remove icon from folder when dropping outside

[Georges Basile Stavracas Neto <gbsneto src gnome org>]

commit b5e513c3e1deb8bcee0ec9dea6c501492e0aa596
Author: Georges Basile Stavracas Neto <georges stavracas gmail com>
Date:   Sat Jun 29 01:26:08 2019 -0300

    allView: Remove icon from folder when dropping outside
    
    When dropping an app icon to outside the folder, remove the
    app from that folder. GNOME Shell is already smart enough
    to figure out the setting changes and update the icons.
    
    https://gitlab.gnome.org/GNOME/gnome-shell/merge_requests/664

 js/ui/appDisplay.js | 45 +++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 45 insertions(+)
---
diff --git a/js/ui/appDisplay.js b/js/ui/appDisplay.js
index 60235f754..3f2387bfc 100644
--- a/js/ui/appDisplay.js
+++ b/js/ui/appDisplay.js
@@ -728,6 +728,38 @@ var AllView = class AllView extends BaseAppView {
         }
     }
 
+    _canDropAt(source) {
+        if (!(source instanceof AppIcon))
+            return false;
+
+        if (!global.settings.is_writable('favorite-apps'))
+            return false;
+
+        if (!(source.view instanceof FolderView))
+            return false;
+
+        return true;
+    }
+
+    handleDragOver(source, actor, x, y, time) {
+        if (!this._canDropAt(source))
+            return DND.DragMotionResult.NO_DROP;
+
+        return DND.DragMotionResult.MOVE_DROP;
+    }
+
+    acceptDrop(source, actor, x, y, time) {
+        if (!this._canDropAt(source))
+            return false;
+
+        source.view.removeApp(source.app);
+
+        if (this._currentPopup)
+            this._currentPopup.popdown();
+
+        return true;
+    }
+
     inhibitEventBlocker() {
         this._nEventBlockerInhibits++;
         this._eventBlocker.visible = this._nEventBlockerInhibits == 0;
@@ -1245,6 +1277,19 @@ var FolderView = class FolderView extends BaseAppView {
 
         return apps;
     }
+
+    removeApp(app) {
+        let folderApps = this._folder.get_strv('apps');
+        let index = folderApps.indexOf(app.id);
+        if (index < 0)
+            return false;
+
+        folderApps.splice(index, 1);
+
+        this._folder.set_strv('apps', folderApps);
+
+        return true;
+    }
 };
 
 var FolderIcon = class FolderIcon {