Windows Phone 7 BorderBrush 只能设置一次？

Question

所以我有这个检查用户输入的验证方法。如果输入错误或丢失，则将文本块的边框设置为红色。否则它会重置它。但是，此代码根本不起作用。有时边框设置为红色，有时则不是应该设置为红色，等等。这几乎就像控件没有重新绘制自己一样？

我做错了什么？

        private SolidColorBrush _errorBorderBrush = new SolidColorBrush(Colors.Red);
        private SolidColorBrush _normalBorderBrush = new SolidColorBrush(Colors.Black);

        private bool Validate()
        {
            if(txtName.Text == string.Empty)
            {
                txtName.BorderBrush = _errorBorderBrush;
                return false;
            }
            else
            {
                txtName.BorderBrush = _normalBorderBrush;
            }

            if (pwdPassword.Password == string.Empty)
            {
                pwdPassword.BorderBrush = _errorBorderBrush;
                return false;
            }
            else
            {
                pwdPassword.BorderBrush = _normalBorderBrush;
            }

            ...
         }

Answer 1

我遇到了同样的问题，虽然我不是 WP7 或 SL/WPF 开发方面的专家，但我认为问题与默认的 TextBox 模板的 Focused 状态有关，但没有恢复 BorderBrush到它的原始设置（Background 属性似乎也存在同样的问题。）我设法通过在 XAML 中使用我自己的模板来解决这个问题......我没有安装 Blend，所以我不知道如何拉出了原模板，但是基于this page我觉得原模板如下：

<Style TargetType="TextBox">
<Setter Property="FontFamily" Value="{StaticResource PhoneFontFamilyNormal}"/>
<Setter Property="FontSize" Value="{StaticResource PhoneFontSizeMediumLarge}"/>
<Setter Property="Background" Value="{StaticResource PhoneTextBoxBrush}"/>
<Setter Property="Foreground" Value="{StaticResource PhoneTextBoxForegroundBrush}"/>
<Setter Property="BorderBrush" Value="{StaticResource PhoneTextBoxBrush}"/>
<Setter Property="SelectionBackground" Value="{StaticResource PhoneAccentBrush}"/>
<Setter Property="SelectionForeground" Value="{StaticResource PhoneTextBoxSelectionForegroundBrush}"/>
<Setter Property="BorderThickness" Value="{StaticResource PhoneBorderThickness}"/>
<Setter Property="Padding" Value="2"/>
<Setter Property="Template">
    <Setter.Value>
        <ControlTemplate TargetType="TextBox">
            <Grid Background="Transparent">
                <VisualStateManager.VisualStateGroups>
                    <VisualStateGroup x:Name="CommonStates">
                        <VisualState x:Name="Normal"/>
                        <VisualState x:Name="MouseOver"/>
                        <VisualState x:Name="Disabled">
                            <Storyboard>
                                <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="EnabledBorder">
                                    <DiscreteObjectKeyFrame KeyTime="0">
                                        <DiscreteObjectKeyFrame.Value>
                                            <Visibility>Collapsed</Visibility>
                                        </DiscreteObjectKeyFrame.Value>
                                    </DiscreteObjectKeyFrame>
                                </ObjectAnimationUsingKeyFrames>
                                <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="DisabledOrReadonlyBorder">
                                    <DiscreteObjectKeyFrame KeyTime="0">
                                        <DiscreteObjectKeyFrame.Value>
                                            <Visibility>Visible</Visibility>
                                        </DiscreteObjectKeyFrame.Value>
                                    </DiscreteObjectKeyFrame>
                                </ObjectAnimationUsingKeyFrames>
                            </Storyboard>
                        </VisualState>
                        <VisualState x:Name="ReadOnly">
                            <Storyboard>
                                <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="EnabledBorder">
                                    <DiscreteObjectKeyFrame KeyTime="0">
                                        <DiscreteObjectKeyFrame.Value>
                                            <Visibility>Collapsed</Visibility>
                                        </DiscreteObjectKeyFrame.Value>
                                    </DiscreteObjectKeyFrame>
                                </ObjectAnimationUsingKeyFrames>
                                <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="DisabledOrReadonlyBorder">
                                    <DiscreteObjectKeyFrame KeyTime="0">
                                        <DiscreteObjectKeyFrame.Value>
                                            <Visibility>Visible</Visibility>
                                        </DiscreteObjectKeyFrame.Value>
                                    </DiscreteObjectKeyFrame>
                                </ObjectAnimationUsingKeyFrames>
                                <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Background" Storyboard.TargetName="DisabledOrReadonlyBorder">
                                    <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PhoneTextBoxBrush}"/>
                                </ObjectAnimationUsingKeyFrames>
                                <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="BorderBrush" Storyboard.TargetName="DisabledOrReadonlyBorder">
                                    <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PhoneTextBoxBrush}"/>
                                </ObjectAnimationUsingKeyFrames>
                                <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Foreground" Storyboard.TargetName="DisabledOrReadonlyContent">
                                    <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PhoneTextBoxReadOnlyBrush}"/>
                                </ObjectAnimationUsingKeyFrames>
                            </Storyboard>
                        </VisualState>
                    </VisualStateGroup>
                    <VisualStateGroup x:Name="FocusStates">
                        <VisualState x:Name="Focused">
                            <Storyboard>
                                <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Background" Storyboard.TargetName="EnabledBorder">
                                    <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PhoneTextBoxEditBackgroundBrush}"/>
                                </ObjectAnimationUsingKeyFrames>
                                <ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="BorderBrush" Storyboard.TargetName="EnabledBorder">
                                    <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PhoneTextBoxEditBorderBrush}"/>
                                </ObjectAnimationUsingKeyFrames>
                            </Storyboard>
                        </VisualState>
                        <VisualState x:Name="Unfocused"/>
                    </VisualStateGroup>
                </VisualStateManager.VisualStateGroups>
                <Border x:Name="EnabledBorder" BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="{TemplateBinding Background}" Margin="{StaticResource PhoneTouchTargetOverhang}">
                    <ContentControl x:Name="ContentElement" BorderThickness="0" HorizontalContentAlignment="Stretch" Margin="{StaticResource PhoneTextBoxInnerMargin}" Padding="{TemplateBinding Padding}" VerticalContentAlignment="Stretch"/>
                </Border>
                <Border x:Name="DisabledOrReadonlyBorder" BorderBrush="{StaticResource PhoneDisabledBrush}" BorderThickness="{TemplateBinding BorderThickness}" Background="Transparent" Margin="{StaticResource PhoneTouchTargetOverhang}" Visibility="Collapsed">
                    <TextBox x:Name="DisabledOrReadonlyContent" Background="Transparent" Foreground="{StaticResource PhoneDisabledBrush}" FontWeight="{TemplateBinding FontWeight}" FontStyle="{TemplateBinding FontStyle}" FontSize="{TemplateBinding FontSize}" FontFamily="{TemplateBinding FontFamily}" IsReadOnly="True" SelectionForeground="{TemplateBinding SelectionForeground}" SelectionBackground="{TemplateBinding SelectionBackground}" TextAlignment="{TemplateBinding TextAlignment}" TextWrapping="{TemplateBinding TextWrapping}" Text="{TemplateBinding Text}" Template="{StaticResource PhoneDisabledTextBoxTemplate}"/>
                </Border>
            </Grid>
        </ControlTemplate>
    </Setter.Value>
</Setter>

我不需要 Focused 状态看起来与 Unfocused 状态不同，因此我将 FocusStates VisualStateGroup 更改为如下所示：

    <VisualStateGroup x:Name="FocusStates">
    <VisualState x:Name="Focused" />
    <VisualState x:Name="Unfocused"/>
</VisualStateGroup>

是的，我知道，这不是最优雅的解决方案，但它对我有用，希望这至少可以帮助您指明正确的方向！

Answer 2

可能是回电。 return 仅表示返回/取消方法。通过返回，您可以直接跳出方法。 因此，如果 txtName 为空，则不会检查 pwdPassword 等。

Answer 3

如果你的逻辑没问题，你对颜色所做的事情应该可以工作。我们无法看到所有内容，但您应该能够在调试器中单步执行它，看看为什么它可能没有被调用。

这里有一些示例代码可以将颜色从绿色更改为红色，然后在连续单击按钮时返回。

页面类字段

SolidColorBrush green = new SolidColorBrush(Colors.Green);
SolidColorBrush red = new SolidColorBrush(Colors.Red);

按钮事件处理程序

    if (textBox1.BorderBrush != green) {
        textBox1.BorderBrush = green;
    } else {
        textBox1.BorderBrush = red;
    }

如果您仍然遇到问题，我建议您创建一个重现项目。它可能会向您揭示问题，如果没有，您可以在此处发布，以便人们查看您的问题可以在哪里重现。