[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 ec8b7bc7b2c39acbef2648ca1cb4d785ab95cd49
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 | 51 +++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 51 insertions(+)
---
diff --git a/js/ui/appDisplay.js b/js/ui/appDisplay.js
index 4cfea7e9cb..6b3095eae0 100644
--- a/js/ui/appDisplay.js
+++ b/js/ui/appDisplay.js
@@ -737,6 +737,37 @@ var AllView = class AllView extends BaseAppView {
         }
     }
 
+    _canAccept(source) {
+        if (!(source instanceof AppIcon))
+            return false;
+
+        let view = _getViewFromIcon(source);
+        if (!(view instanceof FolderView))
+            return false;
+
+        return true;
+    }
+
+    handleDragOver(source) {
+        if (!this._canAccept(source))
+            return DND.DragMotionResult.NO_DROP;
+
+        return DND.DragMotionResult.MOVE_DROP;
+    }
+
+    acceptDrop(source) {
+        if (!this._canAccept(source))
+            return false;
+
+        let view = _getViewFromIcon(source);
+        view.removeApp(source.app);
+
+        if (this._currentPopup)
+            this._currentPopup.popdown();
+
+        return true;
+    }
+
     inhibitEventBlocker() {
         this._nEventBlockerInhibits++;
         this._eventBlocker.visible = this._nEventBlockerInhibits == 0;
@@ -1258,6 +1289,26 @@ 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) {
+            folderApps.splice(index, 1);
+            this._folder.set_strv('apps', folderApps);
+        }
+
+        // If this is a categories-based folder, also add it to
+        // the list of excluded apps
+        let categories = this._folder.get_strv('categories');
+        if (categories.length > 0) {
+            let excludedApps = this._folder.get_strv('excluded-apps');
+            excludedApps.push(app.id);
+            this._folder.set_strv('excluded-apps', excludedApps);
+        }
+
+        return true;
+    }
 };
 
 var FolderIcon = class FolderIcon {