Fix for IE drag/drop issue #252

core/modules/widgets/dropzone.js

@@ -102,8 +102,10 @@ DropZoneWidget.prototype.handleDropEvent  = function(event) {
 DropZoneWidget.prototype.importData = function(dataTransfer) {
 	for(var t=0; t<this.importDataTypes.length; t++) {
 		var dataType = this.importDataTypes[t];
-		var data = dataTransfer.getData(dataType.type);
-		if(data !== "") {
+		try {
+			var data = dataTransfer.getData(dataType.type);
+		} catch(e) { if(e.description !== "Invalid argument.") throw e; }	// deal with formats that IE doesn't support
+		if(data !== "" && data != null) {
 			var tiddlerFields = dataType.convertToFields(data);
 			if(!tiddlerFields.title) {
 				tiddlerFields.title = this.wiki.generateNewTitle("Untitled");
@@ -115,6 +117,22 @@ DropZoneWidget.prototype.importData = function(dataTransfer) {
 };
 
 DropZoneWidget.prototype.importDataTypes = [
+	{type: "URL", convertToFields: function(data) {
+		// check for tiddler data URI
+		var match = decodeURI(data).match(/^data\:text\/vnd\.tiddler,(.*)/i);
+		if(match) {
+			return JSON.parse(match[1]);
+		} else {
+			return {	// as URL string
+				text: data
+			};
+		}
+	}},
+	{type: "Text", convertToFields: function(data) {
+		return {
+			text: data
+		};
+	}},
 	{type: "text/vnd.tiddler", convertToFields: function(data) {
 		return JSON.parse(data);
 	}},

core/modules/widgets/link.js

@@ -125,10 +125,14 @@ LinkWidget.prototype.handleDragStartEvent = function(event) {
 		// Set the data transfer properties
 		var dataTransfer = event.dataTransfer;
 		dataTransfer.effectAllowed = "copy";
-		dataTransfer.setDragImage(this.dragImage.firstChild,-16,-16);
+		if(dataTransfer.setDragImage) {
+			dataTransfer.setDragImage(this.dragImage.firstChild,-16,-16);
+		}
 		dataTransfer.clearData();
 		dataTransfer.setData("text/vnd.tiddler",this.wiki.getTiddlerAsJson(this.to));
 		dataTransfer.setData("text/plain",this.wiki.getTiddlerText(this.to,""));
+		dataTransfer.setData("URL","data:text/vnd.tiddler," + encodeURI(this.wiki.getTiddlerAsJson(this.to)));
+		dataTransfer.setData("Text",this.wiki.getTiddlerText(this.to,""));
 		event.stopPropagation();
 	} else {
 		event.preventDefault();