fix: trigger preventDefault by origin event (#3017)

Author: NewByVector

packages/x6/src/graph/graph.ts

@@ -58,8 +58,12 @@ export class Graph extends Basecoat<EventArgs> {
     this.grid = new Grid(this)
     this.background = new Background(this)
 
-    this.model = this.options.model ? this.options.model : new Model()
-    this.model.graph = this
+    if (this.options.model) {
+      this.model = this.options.model
+    } else {
+      this.model = new Model()
+      this.model.graph = this
+    }
 
     this.renderer = new ViewRenderer(this)
     this.panning = new Panning(this)

packages/x6/src/graph/view.ts

@@ -201,7 +201,7 @@ export class GraphView extends View {
     }
 
     if (this.options.preventDefaultMouseDown) {
-      e.preventDefault()
+      evt.preventDefault()
     }
 
     const localPoint = this.graph.snapToGrid(e.clientX, e.clientY)
@@ -213,7 +213,7 @@ export class GraphView extends View {
         this.options.preventDefaultBlankAction &&
         ['touchstart'].includes(e.type)
       ) {
-        e.preventDefault()
+        evt.preventDefault()
       }
 
       this.graph.trigger('blank:mousedown', {