UWP - PivotItem 鼠标悬停改变颜色

Question

我想在 UWP 鼠标结束时更改 PivotItem Header 的前景颜色，我使用 windows 10

我试过这段代码：

<Page.Resources>
        <SolidColorBrush x:Key="mouseOverColor"
                    Color="Red" />
    </Page.Resources>
<Pivot HeaderTemplate="{StaticResource HeaderTemp}" VerticalAlignment="Top" HorizontalAlignment="Center" Margin="10,0,10,0">
            <VisualStateManager.VisualStateGroups>
                <VisualStateGroup>
                    <VisualState x:Name="Narrow">
                        <VisualState.StateTriggers>
                            <AdaptiveTrigger MinWindowWidth="0" />
                        </VisualState.StateTriggers>
                        <VisualState.Setters>
                            <Setter Target="Icon.(RelativePanel.AlignHorizontalCenterWithPanel)" Value="True" />
                            <Setter Target="LabelText.(RelativePanel.Below)" Value="Icon" />
                            <Setter Target="LabelText.(RelativePanel.AlignHorizontalCenterWith)" Value="Icon" />
                        </VisualState.Setters>
                    </VisualState>
                    <VisualState x:Name="Wide">
                        <VisualState.StateTriggers>
                            <AdaptiveTrigger MinWindowWidth="500" />
                        </VisualState.StateTriggers>
                        <VisualState.Setters>
                            <Setter Target="Icon.(RelativePanel.AlignVerticalCenterWithPanel)" Value="True" />
                            <Setter Target="LabelText.(RelativePanel.RightOf)" Value="Icon" />
                            <Setter Target="LabelText.(RelativePanel.AlignVerticalCenterWith)" Value="Icon" />
                            <Setter Target="RelativePanel.Margin" Value="0,0,12,0"/>
                            <Setter Target="Icon.Margin" Value="0,0,0,0"/>
                        </VisualState.Setters>
                    </VisualState>
                </VisualStateGroup>
            </VisualStateManager.VisualStateGroups>
            <Pivot.Resources>
                <Style x:Key="myStyle" TargetType="PivotItem">
                    <Setter Property="Template">
                        <Setter.Value>
                            <ControlTemplate TargetType="PivotItem">
                                <ControlTemplate.Triggers>
                                    <Trigger Property="IsMouseOver"
                  Value="True">
                                        <Setter Property="Background"
                   Value="{StaticResource mouseOverColor}" />
                                    </Trigger>
                                </ControlTemplate.Triggers>
                                <ContentPresenter />
                            </ControlTemplate>
                        </Setter.Value>
                    </Setter>
                </Style>
            </Pivot.Resources>
            <PivotItem Header="/images/img.png" Margin="12,10,12,0"  >
                <Grid>
                    .....
                </Grid>
            </PivotItem>

我有一个错误 "The attachable property "Triggers" 未在 'ControlTemplate' 类型中找到你知道当鼠标悬停在通用应用程序中时如何更改图像的颜色吗感谢帮助

Answer 1

你想改变图片的颜色，我觉得在XAML设计器里做不到，你可以这样做：

XAML代码：

    <Pivot>
        <PivotItem>
            <PivotItem.Header>
                <Image x:Name="headerimg" Source="Assets/1.jpg" PointerEntered="pointerEntered" PointerExited="pointerExited"/>
            </PivotItem.Header>
        </PivotItem>
    </Pivot>

.cs 文件中的关键代码：

private async void pointerEntered(object sender, PointerRoutedEventArgs e)
{
    StorageFile imgFile = await StorageFile.GetFileFromApplicationUriAsync(new Uri("ms-appx:///Assets\1.jpg"));
    using(IRandomAccessStream streamIn = await imgFile.OpenReadAsync())
    {
        //decoder the img
        BitmapDecoder decoder = await BitmapDecoder.CreateAsync(BitmapDecoder.JpegDecoderId, streamIn);
        //get pixel
        PixelDataProvider proved = await decoder.GetPixelDataAsync(BitmapPixelFormat.Bgra8, BitmapAlphaMode.Straight, new BitmapTransform(),
            ExifOrientationMode.IgnoreExifOrientation, ColorManagementMode.DoNotColorManage);
        byte[] srcData = proved.DetachPixelData();

        // GRAYSCALE
        for (int i = 0; i < srcData.Length; i += 4)
        {
            double b = srcData[i]; //B
            double g = srcData[i + 1]; //G
            double r = srcData[i + 2]; //R
            //average
            double v = (r + g + b) / 3d;
            //replace old rgb
            srcData[i] = srcData[i + 1] = srcData[i + 2] = Convert.ToByte(v);
        }

        WriteableBitmap wbimg = new WriteableBitmap((int)decoder.PixelWidth, (int)decoder.PixelHeight);
        srcData.CopyTo(wbimg.PixelBuffer);
        this.headerimg.Source = wbimg;
    }

}

private async void pointerExited(object sender, PointerRoutedEventArgs e)
{
    StorageFile imgFile = await StorageFile.GetFileFromApplicationUriAsync(new Uri("ms-appx:///Assets\1.jpg"));
    IRandomAccessStream streamIn = await imgFile.OpenReadAsync();
    BitmapImage bitmap = new BitmapImage();
    bitmap.SetSource(streamIn);
    this.headerimg.Source = bitmap;
}

要更改图像的颜色，您需要解码此图像，获取其 RGB 值，重写这些值并将它们转回图像。 Image 控件没有 Foreground 属性。

UWP - PivotItem 鼠标悬停改变颜色

UWP - PivotItem mouse over change color

c#

xaml

win-universal-app

windows-10-universal