在gridview中拖动项目

Question

我有一个动态行数和3列的网格.在某个时刻只能看到3行.在网格中我可以有空单元格.您是否知道如何在单元格的视图上实现视图的拖放功能？我希望能够在空单元格中拖动项目.

Answer 1

在这里我想再添加一个示例、参考和一些代码片段。

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拖动代码\n 让\xe2\x80\x99s 看看控件的实现以及我们如何处理拖动项。

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        public class GridViewEx : GridView\n        {\n            /// <summary>\n            /// Initializes a new instance of the <see cref="GridViewEx"/> control.\n            /// </summary>\n            public GridViewEx()\n            {\n                // see attached sample\n            }\n\n            private void GridViewEx_DragItemsStarting(object sender, DragItemsStartingEventArgs e)\n            {\n                // see attached sample\n            }\n\n            /// <summary>\n            /// Stores dragged items into DragEventArgs.Data.Properties["Items"] value.\n            /// Override this method to set custom drag data if you need to.\n            /// </summary>\n            protected virtual void OnDragStarting(DragItemsStartingEventArgs e)\n            {\n                // see attached sample\n            }\n     The control has several fields which store the indices of several active items during the drag/drop process. The OnDragStarting\n

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事件将拖动的项目存储到\n DragEventArgs.Data.Properties[\xe2\x80\x9cItems\xe2\x80\x9d] 值中。如果需要，您可以重写此\n 方法来设置自定义拖动数据。\n 当用户拖动某个项目时，我们需要显示有关该项目在放下后将放置在何处的提示。标准 GridView 通过将相邻项目滑开来处理此问题。我们将在 GridViewEx 中自己实现这一精确的行为，因为我们需要考虑 GridView 不支持拖放的情况。

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    /// <summary>\n    /// Shows reoder hints while custom dragging.\n    /// </summary>\n    protected override void OnDragOver(DragEventArgs e)\n    {\n        // see attached sample }\n\n    private int GetDragOverIndex(DragEventArgs e)\n    {\n        // see attached sample \n    }\n\n\n Dropping Code\n Next, let\xe2\x80\x99s look at the code that handles dropping.\n We have to override GridView.OnDrop method which is called every time when an end-user drops an item to the new location. Our override\n

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处理标准 GridView 不支持删除的任何 ItemsPanel 的删除。

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 /// <summary>\n/// Handles drag and drop for cases when it is not supported by the Windows.UI.Xaml.Controls.GridView control\n/// </summary>\nprotected override async void OnDrop(DragEventArgs e)\n{\n    // see attached sample\n} \n The OnDrop method includes logic for moving items from one group to another when grouping is enabled, and for new group creation if it\n

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由最终用户操作请求。

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有关更多详细信息，您可以参考以下链接通过拖放扩展 GridView 以进行分组和可变大小的项目

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您也可以点击以下链接Android 拖放示例

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希望，这可以帮助你。

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