xamarin - 在内容页面中添加新工具栏图标时出现投射异常
问题描述
在我的内容页面工具栏图标上添加新工具栏项目时,它会引发异常:
System.InvalidCastException:指定的强制转换无效。在 Xamarin.Forms.ButtonElement.OnCommandChanging (Xamarin.Forms.BindableObject bo, System.Object o, System.Object n)
这是我添加新工具栏项的代码:
ToolbarItem deleteItem = new ToolbarItem();
deleteItem.Icon = "DeleteIcon";
deleteItem.Text = "Delete";
deleteItem.Order = ToolbarItemOrder.Default;
deleteItem.Priority = 1;
deleteItem.SetBinding(Button.CommandProperty, new Binding("DeleteTransaction"));
this.CurrentPage.ToolbarItems.Add(deleteItem); //error throwing on this line
如何解决这个问题?
解决方案
您的问题是命令的强制转换,请查看此示例。这是MenuItem.CommandProperty
var toolbarItem = new ToolbarItem();
toolbarItem.SetBinding(MenuItem.CommandProperty, new Binding("ActionBarButtonCommand"));
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