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ui.Map.DrawingTools.onLayerSelect
透過集合功能整理內容
你可以依據偏好儲存及分類內容。
註冊在選取圖層時觸發的回呼。
傳回可傳遞至 unlisten() 的 ID，用於取消註冊回呼。
| 用量 | 傳回 |
|---|
DrawingTools.onLayerSelect(callback) | 字串 |
| 引數 | 類型 | 詳細資料 |
|---|
這個：ui.map.drawingtools | ui.Map.DrawingTools | ui.Map.DrawingTools 執行個體。 |
callback | 函式 | 選取形狀時要觸發的回呼。回呼會傳遞兩個參數：所選的 GeometryLayer (或取消選取時的空值)，以及事件監聽器繫結的 ui.Map.DrawingTools 小工具。 |
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上次更新時間：2025-07-26 (世界標準時間)。
[null,null,["上次更新時間：2025-07-26 (世界標準時間)。"],[[["\u003cp\u003eRegisters a callback function that is executed when a layer is selected within the DrawingTools.\u003c/p\u003e\n"],["\u003cp\u003eProvides a method, \u003ccode\u003eonLayerSelect\u003c/code\u003e, to register the callback, accepting the callback function as an argument and returning a unique ID.\u003c/p\u003e\n"],["\u003cp\u003eThe callback function receives the selected GeometryLayer (or null if deselected) and the DrawingTools widget as parameters.\u003c/p\u003e\n"],["\u003cp\u003eThe returned ID can be utilized with the \u003ccode\u003eunlisten()\u003c/code\u003e method to unregister the callback when it's no longer needed.\u003c/p\u003e\n"]]],["A callback function is registered to be executed upon layer selection. The `onLayerSelect` method takes a callback as an argument, which receives the selected `GeometryLayer` (or null if deselected) and the `ui.Map.DrawingTools` instance. This method returns a unique string ID, enabling the callback to be unregistered later via the `unlisten()` method. The method's `ui.Map.DrawingTools` instance is implicitly bound to this.\n"],null,["# ui.Map.DrawingTools.onLayerSelect\n\n\u003cbr /\u003e\n\nRegisters a callback that's fired when a layer is selected.\n\n\u003cbr /\u003e\n\nReturns an ID which can be passed to unlisten() to unregister the callback.\n\n| Usage | Returns |\n|----------------------------------------|---------|\n| DrawingTools.onLayerSelect`(callback)` | String |\n\n| Argument | Type | Details |\n|-----------------------------|---------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| this: `ui.map.drawingtools` | ui.Map.DrawingTools | The ui.Map.DrawingTools instance. |\n| `callback` | Function | The callback to fire when a shape is selected. The callback is passed two parameters: the selected GeometryLayer (or null for deselect) and the ui.Map.DrawingTools widget that the event listener is bound to. |"]]
