如何从其单击事件WPF停止按钮命令的执行
本文关键字：按钮 命令 执行 WPF 单击 事件 | 更新日期: 2023-09-27 18:18:46
是否有任何方法可以根据其单击事件的某些条件停止按钮命令执行?
实际上，我希望在我们的应用程序中的某些按钮点击时弹出确认。为了使它成为一个通用的解决方案，我做了以下工作:
- 我已经扩展了WPF按钮类调用
- 我有两个以上的属性如下:
IsActionConfirmationRequired和ConfirmationActionCommand。
AppBarButton，它已经包含一些依赖属性。如果IsActionConfirmationRequired然后在左键点击事件，我打开确认弹出。
是否有任何方法可以避免创建新的ConfirmationActionCommand，并使用Button相同的Command属性?如果我设置Command，那么在Button上单击，即使用户没有确认动作仍然按钮命令执行。
public class AppBarButton : Button
{
public AppBarButton()
{
this.Click += AppBarButton_Click;
}
private void AppBarButton_Click(object sender, RoutedEventArgs e)
{
Button button = sender as Button;
if (button == null || IsActionConfirmationRequired == false || ConfirmationActionCommand == null)
return;
const string defaultMessage = "Do you really want to {0}";
string confirmationPopUpMessage = string.IsNullOrEmpty(ActionConfirmationMessage)
? DebugFormat.Format(defaultMessage, button.Content)
: ActionConfirmationMessage;
ConfirmationDailogDetails confirmationDailogDetails = new ConfirmationDailogDetails
{
Message = confirmationPopUpMessage,
ActionName = button.Content.ToString(),
Template = button.Template,
ActionCommand = ConfirmationActionCommand
};
//instead of ConfirmationActionCommand want to use base.Command
ConfirmationDailog dialog = new ConfirmationDailog(confirmationDailogDetails)
{
PlacementTarget = button,
IsOpen = true
};
}
public static readonly DependencyProperty IsActionConfirmationRequiredProperty =
DependencyProperty.Register("IsActionConfirmationRequired", typeof(bool), typeof(AppBarButton));
public static readonly DependencyProperty ActionConfirmationMessageProperty =
DependencyProperty.Register("ActionConfirmationMessage", typeof(string), typeof(AppBarButton));
public static readonly DependencyProperty ConfirmationActionCommandProperty =
DependencyProperty.Register("ConfirmationActionCommand", typeof(ICommand), typeof(AppBarButton));
/// <summary>
/// Gets or sets the flag to show the confirmation popup on before taking any action on App Bar button click.
/// Also its required to set the command in Tag Property of the App Bar button not in the Command Property, then only required command will fire only when user
/// confirms and click on the action button on confirmation popup.
/// </summary>
public bool IsActionConfirmationRequired
{
get { return (bool)GetValue(IsActionConfirmationRequiredProperty); }
set { SetValue(IsActionConfirmationRequiredProperty, value); }
}
/// <summary>
/// Gets or sets the confirmation message in confirmation popup before taking any action on App Bar button click.
/// </summary>
public ICommand ConfirmationActionCommand
{
get { return (ICommand)GetValue(ConfirmationActionCommandProperty); }
set { SetValue(ConfirmationActionCommandProperty, value); }
}
}
<controls:AppBarButton x:Key="WithdrawAll"
AppBarOrder="1"
PageIndex="1"
AppBarOrientation="Left"
Content="Withdraw" IsActionConfirmationRequired="True"
ConfirmationActionCommand="{Binding WithdrawAllCommand}"
Template="{StaticResource DeleteCircleIcon}" />
请提出建议。我什么也找不到。已经尝试了CanExecute为假，但它的使按钮禁用，所以没有使用。我只是简单地不想做另一个命令，开发人员将使用这个AppBarButton需要设置ConfirmationActionCommand而不是正常的Command。
如果我理解正确的话，您想要确认用户的操作并执行存储在ButtonBase.Command属性中的命令。
要实现这一点，请删除ConfirmationActionCommand属性并使用OnClick方法而不是Click事件。在重写的OnClick方法中，调用基方法，如果用户确认操作或不需要确认，则基方法将执行来自Command属性的命令。
public class AppBarButton : Button
{
public static readonly DependencyProperty IsActionConfirmationRequiredProperty =
DependencyProperty.Register("IsActionConfirmationRequired", typeof(bool), typeof(AppBarButton));
public static readonly DependencyProperty ActionConfirmationMessageProperty =
DependencyProperty.Register("ActionConfirmationMessage", typeof(string), typeof(AppBarButton));
public bool IsActionConfirmationRequired
{
get { return (bool)GetValue(IsActionConfirmationRequiredProperty); }
set { SetValue(IsActionConfirmationRequiredProperty, value); }
}
public string ActionConfirmationMessage
{
get { return (string)GetValue(ActionConfirmationMessageProperty ); }
set { SetValue(ActionConfirmationMessageProperty , value); }
}
protected override void OnClick()
{
bool confirmed = true;
if (IsActionConfirmationRequired)
{
ConfirmationDailogDetails confirmationDailogDetails = new ConfirmationDailogDetails
{
Message = confirmationPopUpMessage,
ActionName = button.Content.ToString(),
Template = button.Template,
ActionCommand = ConfirmationActionCommand
};
ConfirmationDailog dialog = new ConfirmationDailog(confirmationDailogDetails)
{
PlacementTarget = button,
IsOpen = true
};
// Set confirmed here
// If you set the DialogResult property in the ConfirmationDailog class then
// confirmed = dialog.ShowDialog().Value;
}
// If there is no confirmation requred or if an user have confirmed an action
// then call base method which will execute a command if it exists.
if (confirmed)
{
base.OnClick();
}
}
}
处理PreviewMouseLeftButtonDown事件，而不是点击事件。这在命令执行之前发生。在处理程序中请求确认并将event的Handled属性设置为true或false。
如果设置为true，则不执行该命令。
private void btn_PreviewMouseLeftButtonUp(object sender, MouseButtonEventArgs e)
{
var confirmed = true; //use your confirmation instead
e.Handled = confirmed;
}
这是你的代码可能看起来像(我不知道确切的，因为我没有ConfirmationDailog的代码:
public class AppBarButton : Button
{
public AppBarButton()
{
this.PreviewMouseLeftButtonDown += AppBarButton_PreviewMouseLeftButtonDown; ;
}
private void AppBarButton_PreviewMouseLeftButtonDown(object sender, RoutedEventArgs e)
{
Button button = sender as Button;
if (button == null || IsActionConfirmationRequired == false || ConfirmationActionCommand == null)
return;
const string defaultMessage = "Do you really want to {0}";
string confirmationPopUpMessage = string.IsNullOrEmpty(ActionConfirmationMessage)
? DebugFormat.Format(defaultMessage, button.Content)
: ActionConfirmationMessage;
ConfirmationDailogDetails confirmationDailogDetails = new ConfirmationDailogDetails
{
Message = confirmationPopUpMessage,
ActionName = button.Content.ToString(),
Template = button.Template,
ActionCommand = ConfirmationActionCommand
};
**//instead of ConfirmationActionCommand want to use base.Command**
ConfirmationDailog dialog = new ConfirmationDailog(confirmationDailogDetails)
{
PlacementTarget = button,
IsOpen = true
};
//validation here
dialog.ShowDialog();
var confirmed = dialog.IsConfirmed;
e.Handled = confirmed;
}
...