Set drag and drop event listener

Signed-off-by: dab246 <[email protected]>

Author: dab246

lib/src/html_editor_controller_mobile.dart

@@ -298,4 +298,7 @@ class HtmlEditorController extends unsupported.HtmlEditorController {
 
   @override
   void removeSignature() {}
+
+  @override
+  void setOnDragDropEvent() {}
 }

lib/src/html_editor_controller_unsupported.dart

@@ -195,4 +195,7 @@ class HtmlEditorController {
 
   /// Update body direction on web
   void updateBodyDirection(String direction) {}
+
+  /// Set drag and drop event listener
+  void setOnDragDropEvent() {}
 }

lib/src/html_editor_controller_web.dart

@@ -400,4 +400,9 @@ class HtmlEditorController extends unsupported.HtmlEditorController {
   void updateBodyDirection(String direction) {
     _evaluateJavascriptWeb(data: {'type': 'toIframe: updateBodyDirection', 'direction': direction});
   }
+
+  @override
+  void setOnDragDropEvent() {
+    _evaluateJavascriptWeb(data: {'type': 'toIframe: onDragDropEvent'});
+  }
 }

lib/src/widgets/html_editor_widget_web.dart

@@ -480,6 +480,15 @@ class _HtmlEditorWidgetWebState extends State<HtmlEditorWidget> {
                 const contentsEditor = document.getElementsByClassName('note-editable')[0].innerHTML;
                 window.parent.postMessage(JSON.stringify({"view": "$createdViewId", "type": "toDart: onChangeContent", "contents": contentsEditor}), "*");
               }
+              if (data["type"].includes("onDragDropEvent")) {
+                document.getElementsByClassName('note-editor')[0].addEventListener("dragenter", function(event) {
+                  window.parent.postMessage(JSON.stringify({"view": "$createdViewId", "type": "toDart: onDragEnter"}), "*");
+                });
+                
+                document.getElementsByClassName('note-editor')[0].addEventListener("dragleave", function(event) {
+                  window.parent.postMessage(JSON.stringify({"view": "$createdViewId", "type": "toDart: onDragLeave"}), "*");
+                });
+              }
               $userScripts
             }
           }
@@ -934,6 +943,12 @@ class _HtmlEditorWidgetWebState extends State<HtmlEditorWidget> {
         if (data['type'].contains('onTextFontSizeChanged')) {
           c.onTextFontSizeChanged!.call(data['size']);
         }
+        if (data['type'].contains('onDragEnter') && c.onDragEnter != null) {
+          c.onDragEnter!.call();
+        }
+        if (data['type'].contains('onDragLeave') && c.onDragLeave != null) {
+          c.onDragLeave!.call();
+        }
       }
     });
   }

lib/utils/callbacks.dart

@@ -26,6 +26,8 @@ class Callbacks {
     this.onPaste,
     this.onScroll,
     this.onTextFontSizeChanged,
+    this.onDragEnter,
+    this.onDragLeave,
   });
 
   /// Called before certain commands are fired and the editor is in rich text view.
@@ -188,4 +190,8 @@ class Callbacks {
 
   /// Called whenever the mouse/finger is released and the editor is in rich text view.
   void Function(int?)? onTextFontSizeChanged;
+
+  void Function()? onDragEnter;
+
+  void Function()? onDragLeave;
 }