WPF ToggleButton 不正确的渲染行为 [英] WPF ToggleButton incorrect render behavior

问题描述

这里发生了什么，如何解决?

What is going on here, and how to do a workaround?

1. 按我的切换按钮.现在它看起来像是立即按下(选中).
2. 同时 MyToggleButton_Checked 处理程序禁用 MyToggleButton.
3. 现在按下非切换按钮启用".我们看到了什么?MyToggleButton 看起来像是已启用.好的.但是等等，现在它看起来像非按下！为什么?！

XAML:

<StackPanel>

    <ToggleButton x:Name="MyToggleButton" Content="MyToggleButton" Checked="MyToggleButton_Checked"/>

    <TextBlock Text="{Binding IsChecked, ElementName=MyToggleButton}" Margin="0,4"/>

    <Button Name="EnableButton" Content="Enable" Click="EnableButton_Click"/>
    <Button Name="DisableButton" Content="Disable" Click="DisableButton_Click"/>

</StackPanel>

代码隐藏:

void MyToggleButton_Checked(object sender, RoutedEventArgs e)
{
    MyToggleButton.IsEnabled = false;
}


void EnableButton_Click(object sender, RoutedEventArgs e)
{
    MyToggleButton.IsEnabled = true;
}

void DisableButton_Click(object sender, RoutedEventArgs e)
{
    MyToggleButton.IsEnabled = false;
}

UPD:

目前唯一可能的解决方法是:

The only possible workaround on the moment is:

void EnableButton_Click(object sender, RoutedEventArgs e)
{
    MyToggleButton.IsEnabled = true;

    var controlTemplate = MyToggleButton.Template;

    var buttonChrome = (Microsoft.Windows.Themes.ButtonChrome)controlTemplate.FindName("Chrome", MyToggleButton);

    buttonChrome.RenderPressed = false;

    buttonChrome.RenderPressed = true;
}

还有其他的吗?

UPD2:

另一种解决方法是:

void EnableButton_Click(object sender, RoutedEventArgs e)
{
    MyToggleButton.IsEnabled = true;

    var controlTemplate = MyToggleButton.Template;
    MyToggleButton.Template = null;
    MyToggleButton.Template = controlTemplate;
}

但是在模板替换的那一刻控件闪烁.

But the control is flickering at the moment of template substitution.

推荐答案

这就是我对问题的解决方案，这里是 视频，用法:

That's my solution for the problem, here is the video, the usage:

<StackPanel>
    <ToggleButton x:Name="MyToggleButton" Content="MyToggleButton" Checked="MyToggleButton_Checked"
                    l:CorrectToggleButtonCheckedEnableBehavior.IsActive="True"/>
    <Button Name="EnableButton" Content="Enable" Click="EnableButton_Click"/>
</StackPanel>

以及附加的行为源代码:

and the attached behavior source code:

public static class CorrectToggleButtonCheckedEnableBehavior
{
    public static bool GetIsActive(ToggleButton toggleButton)
    {
        return (bool)toggleButton.GetValue(IsActiveProperty);
    }

    public static void SetIsActive(ToggleButton toggleButton, bool value)
    {
        toggleButton.SetValue(IsActiveProperty, value);
    }

    public static readonly DependencyProperty IsActiveProperty =
        DependencyProperty.RegisterAttached("IsActive", typeof(bool), typeof(CorrectToggleButtonCheckedEnableBehavior),
        new UIPropertyMetadata(false, OnIsActiveChanged));

    static void OnIsActiveChanged(DependencyObject d, DependencyPropertyChangedEventArgs e)
    {
        var toggleButton = (ToggleButton)d;

        if (GetIsActive(toggleButton))
        {
            toggleButton.IsEnabledChanged += new DependencyPropertyChangedEventHandler(ToggleButton_IsEnabledChanged);
        }
        else
        {
            toggleButton.IsEnabledChanged -= new DependencyPropertyChangedEventHandler(ToggleButton_IsEnabledChanged);
        }
    }

    static void ToggleButton_IsEnabledChanged(object sender, DependencyPropertyChangedEventArgs e)
    {
        var toggleButton = (ToggleButton)sender;

        if (toggleButton.IsEnabled && (toggleButton.IsChecked ?? false))
        {
            Invalidate(toggleButton);
        }
    }

    static void Invalidate(ToggleButton toggleButton)
    {
        var controlTemplate = toggleButton.Template;
        toggleButton.Template = null;
        toggleButton.Template = controlTemplate;
    }
}

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