fix(*): drag over part is set properly

Author: mtsvyatkova

src/components/tile-manager/themes/tile.base.scss

@@ -72,7 +72,7 @@
     z-index: 10;
 }
 
-// [part~='drag-over'] {
-//     opacity: 0.5;
-//     pointer-events: none;
-// }
+[part~='drag-over'] {
+    opacity: 0.5;
+    pointer-events: none;
+}

src/components/tile-manager/tile.ts

@@ -93,6 +93,7 @@ export default class IgcTileComponent extends EventEmitterMixin<
   private _maximized = false;
   private _initialPointerX: number | null = null;
   private _initialPointerY: number | null = null;
+  private _dragCounter = 0;
   private _dragGhost: HTMLElement | null = null;
   private _dragImage: HTMLElement | null = null;
   private _cachedStyles: {
@@ -330,6 +331,7 @@ export default class IgcTileComponent extends EventEmitterMixin<
   }
 
   private handleDragEnter() {
+    this._dragCounter++;
     this._hasDragOver = true;
   }
 
@@ -351,7 +353,13 @@ export default class IgcTileComponent extends EventEmitterMixin<
   }
 
   private handleDragLeave() {
-    this._hasDragOver = false;
+    this._dragCounter--;
+
+    // The drag leave is fired on entering a child element
+    // so we need to check if the dragged item is actually leaving the tile
+    if (this._dragCounter === 0) {
+      this._hasDragOver = false;
+    }
   }
 
   private handleDragEnd() {