由UIAbility创建的一个子窗口，能配置为可拖动吗

.onTouch((event: TouchEvent) =>{ 
   if(event.type == TouchType.Move){ 
     let touchObject : TouchObject = event.changedTouches[0]; 
     let xOffset = this.selfWindow.getWindowProperties().windowRect.left + touchObject.x; 
     let yOffset = this.selfWindow.getWindowProperties().windowRect.top + touchObject.y; 
     this.tabWindowController.moveWindow(this.selfwindow, xOffset,yOffset); 
   } 
 })