如何取消/不接受Flex 3中的拖放操作？

目標： 允許用戶從AdvancedDataGrid拖放一行，將其放到垃圾桶圖標上並刪除記錄，並驗證用戶是否打算通過彈出警報以「確定」和「取消」鈕釦。如何取消/不接受Flex 3中的拖放操作？

什麼是工作：

拖動/刪除一行到垃圾桶圖標。
如果用戶單擊「確定」按鈕，該記錄將被刪除。
如果用戶點擊「取消」按鈕，操作被取消。

問題：用戶點擊「取消」按鈕，並在彈出警報關閉 後，在ADG沒有行可拖動。我發現在排序ADG後，通過單擊列標題，用戶可以開始再次拖動行。

代碼：（從原來的職位變化）

<mx:Image source="{trashImage}" buttonMode="true" 
toolTip="drag a participant here to delete them from the project" 
dragDrop="deleteParticipantDrop(event)" dragEnter="deleteParticipantEnter(event)" 
dragExit="deleteParticipantDragExit(event)" top="4" right="122" id="image2" /> 

// trashImage Event Handlers: 
private function deleteParticipantEnter(event:DragEvent):void 
{ 
    var component:IUIComponent = IUIComponent(event.currentTarget); 
    dragComponent = component; 
    DragManager.acceptDragDrop(component); 
    DragManager.showFeedback(DragManager.MOVE); 
    deleteParticipantDragEvent = event; 
} 

private function deleteParticipantDrop(event:DragEvent):void 
{ 
    var selectedKitNum:String = memberRpt.selectedItem.KitNum; 
    var selectedName:String = memberRpt.selectedItem.ParticipantName; 
    var component:IUIComponent = IUIComponent(event.currentTarget); 
    dragComponent = component; 
    DragManager.acceptDragDrop(component); 
    isEditingParticipantInfo = false; 
    isDeletingParticipant = true; 
    deleteParticipantDropEvent = event; 
    event.stopImmediatePropagation(); // Added as per mrm 
    alert.confirm("Are you sure you want to delete this participant, Kit #" + memberRpt.selectedItem.KitNum + " (" + 
     memberRpt.selectedItem.ParticipantName + ") from the project? This cannot be reversed!! An email will be " + 
     "sent to notify this participant and you will receive a copy of it for your records.", confirmRemoveParticipant); 
} 

private function deleteParticipantDragExit(event:DragEvent):void 
{ 
    var component:IUIComponent = IUIComponent(event.currentTarget); 
    dragComponent = component; 
    DragManager.acceptDragDrop(component); 
    DragManager.showFeedback(DragManager.NONE); 
} 

private function confirmRemoveParticipant(event:CloseEvent):void 
{ 
    if (event.detail == Alert.YES) 
    { 
     deleteReason = DeleteParticipantTitleWindow(PopUpManager.createPopUp(this, DeleteParticipantTitleWindow , true)); 
     dispatchEvent(deleteParticipantDropEvent); // Added as per mrm 
     PopUpManager.centerPopUp(deleteReason); 
     deleteReason.showCloseButton = true; 
     deleteReason.title = "Reason for removal from project"; 
     deleteReason.addEventListener("close", cleanupRemoveParticipant); 
     deleteReason["cancelButton"].addEventListener("click", cleanupRemoveParticipant); 
     deleteReason["okButton"].addEventListener("click", finalizeDeleteParticipant); 
     isDeletingParticipant = false; 
    } 
    else 
    { 
     cleanupRemoveParticipant(); 
    } 
} 

private function cleanupRemoveParticipant(event:Event = null):void 
{ 
    memberRpt.invalidateDisplayList(); 
    memberRpt.executeBindings(); 
    if (deleteReason != null) 
    { 
     PopUpManager.removePopUp(deleteReason); 
     deleteReason = null; 
    } 
} 

public function finalizeDeleteParticipant(event:Event):void 
{ 
    if (deleteReason.reason.text != null) 
    { 
     selectedReportItem = memberRpt.selectedItem; 
     selectedReportItemIndex = memberRpt.selectedIndex; 
     memberReportData.removeItemAt(selectedReportItemIndex); 
    } 
    else 
    { 
     alert.info("You must provide a reason for removing a participant from your project!!"); 
    } 

    cleanupRemoveParticipant(); 
}

預先感謝所有有用的建議。

來源

2008-10-21 Sean Staats