随笔- 47 文章- 0 评论- 174 阅读- 69595

Windows 8开发 ApplicationBar的图标与对应的Unicode编码

首先先来认识一下ApplicationBar中的图标：

与WP7的ApplicationBar的图标样式很像，但是，他们的实现方式却是不同的。WP7的ApplicationBar的按钮图标来源于固定大小的背景透明的图片，而在Win8中，尽管也可以按照WP7的方式自定义Button，但是考虑到各种设备的屏幕分辨率不同（WP7开发时主要只需要考虑800*480），用图片无法完美适配，所以使用了Segoe UI Symbol字体来对特定的Unicode字符进行绘制。

在Windows 8应用商店APP开发时，新建一个APP默认会在common/StandardStyles.xaml文件内加入各种通用的样式，其中ApplicationBar的样式也被包含在内，如下：

AppBarButtonStyle

<Style x:Key="AppBarButtonStyle" TargetType="Button">
        <Setter Property="Foreground" Value="{StaticResource AppBarItemForegroundThemeBrush}"/>
        <Setter Property="VerticalAlignment" Value="Stretch"/>
        <Setter Property="FontFamily" Value="Segoe UI Symbol"/>
        <Setter Property="FontWeight" Value="Normal"/>
        <Setter Property="FontSize" Value="20"/>
        <Setter Property="AutomationProperties.ItemType" Value="App Bar Button"/>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="Button">
                    <Grid Width="100" Background="Transparent">
                        <StackPanel VerticalAlignment="Top" Margin="0,14,0,13">
                            <Grid Width="40" Height="40" Margin="0,0,0,5" HorizontalAlignment="Center">
                                <TextBlock x:Name="BackgroundGlyph" Text="&#xE0A8;" FontFamily="Segoe UI Symbol" FontSize="53.333" Margin="-4,-19,0,0" Foreground="{StaticResource AppBarItemBackgroundThemeBrush}"/>
                                <TextBlock x:Name="OutlineGlyph" Text="&#xE0A7;" FontFamily="Segoe UI Symbol" FontSize="53.333" Margin="-4,-19,0,0"/>
                                <ContentPresenter x:Name="Content" HorizontalAlignment="Center" Margin="-1,-1,0,0" VerticalAlignment="Center"/>
                            </Grid>
                            <TextBlock
                                x:Name="TextLabel"
                                Text="{TemplateBinding AutomationProperties.Name}"
                                Margin="0,0,2,0"
                                FontSize="12"
                                TextAlignment="Center"
                                Width="88"
                                MaxHeight="32"
                                TextTrimming="WordEllipsis"
                                Style="{StaticResource BasicTextStyle}"/>
                        </StackPanel>
                        <Rectangle
                                x:Name="FocusVisualWhite"
                                IsHitTestVisible="False"
                                Stroke="{StaticResource FocusVisualWhiteStrokeThemeBrush}"
                                StrokeEndLineCap="Square"
                                StrokeDashArray="1,1"
                                Opacity="0"
                                StrokeDashOffset="1.5"/>
                        <Rectangle
                                x:Name="FocusVisualBlack"
                                IsHitTestVisible="False"
                                Stroke="{StaticResource FocusVisualBlackStrokeThemeBrush}"
                                StrokeEndLineCap="Square"
                                StrokeDashArray="1,1"
                                Opacity="0"
                                StrokeDashOffset="0.5"/>

                        <VisualStateManager.VisualStateGroups>
                            <VisualStateGroup x:Name="CommonStates">
                                <VisualState x:Name="Normal"/>
                                <VisualState x:Name="PointerOver">
                                    <Storyboard>
                                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="BackgroundGlyph" Storyboard.TargetProperty="Foreground">
                                            <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource AppBarItemPointerOverBackgroundThemeBrush}"/>
                                        </ObjectAnimationUsingKeyFrames>
                                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="Content" Storyboard.TargetProperty="Foreground">
                                            <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource AppBarItemPointerOverForegroundThemeBrush}"/>
                                        </ObjectAnimationUsingKeyFrames>
                                    </Storyboard>
                                </VisualState>
                                <VisualState x:Name="Pressed">
                                    <Storyboard>
                                        <DoubleAnimation
                                            Storyboard.TargetName="OutlineGlyph"
                                            Storyboard.TargetProperty="Opacity"
                                            To="0"
                                            Duration="0"/>
                                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="BackgroundGlyph" Storyboard.TargetProperty="Foreground">
                                            <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource AppBarItemForegroundThemeBrush}"/>
                                        </ObjectAnimationUsingKeyFrames>
                                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="Content" Storyboard.TargetProperty="Foreground">
                                            <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource AppBarItemPressedForegroundThemeBrush}"/>
                                        </ObjectAnimationUsingKeyFrames>
                                    </Storyboard>
                                </VisualState>
                                <VisualState x:Name="Disabled">
                                    <Storyboard>
                                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="OutlineGlyph" Storyboard.TargetProperty="Foreground">
                                            <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource AppBarItemDisabledForegroundThemeBrush}"/>
                                        </ObjectAnimationUsingKeyFrames>
                                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="Content" Storyboard.TargetProperty="Foreground">
                                            <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource AppBarItemDisabledForegroundThemeBrush}"/>
                                        </ObjectAnimationUsingKeyFrames>
                                        <ObjectAnimationUsingKeyFrames Storyboard.TargetName="TextLabel" Storyboard.TargetProperty="Foreground">
                                            <DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource AppBarItemDisabledForegroundThemeBrush}"/>
                                        </ObjectAnimationUsingKeyFrames>
                                    </Storyboard>
                                </VisualState>
                            </VisualStateGroup>
                            <VisualStateGroup x:Name="FocusStates">
                                <VisualState x:Name="Focused">
                                    <Storyboard>
                                        <DoubleAnimation
                                                Storyboard.TargetName="FocusVisualWhite"
                                                Storyboard.TargetProperty="Opacity"
                                                To="1"
                                                Duration="0"/>
                                        <DoubleAnimation
                                                Storyboard.TargetName="FocusVisualBlack"
                                                Storyboard.TargetProperty="Opacity"
                                                To="1"
                                                Duration="0"/>
                                    </Storyboard>
                                </VisualState>
                                <VisualState x:Name="Unfocused" />
                                <VisualState x:Name="PointerFocused" />
                            </VisualStateGroup>
                        </VisualStateManager.VisualStateGroups>
                    </Grid>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>

可以注意到，在AppBarButtonStyle下面，已经默认创建了一些常用的样式，每个样式的区别就是Content的Value的值。

<Style x:Key="DeleteAppBarButtonStyle" TargetType="Button" BasedOn="{StaticResource AppBarButtonStyle}">
        <Setter Property="AutomationProperties.AutomationId" Value="DeleteAppBarButton"/>
        <Setter Property="AutomationProperties.Name" Value="Delete"/>
        <Setter Property="Content" Value="&#xE106;"/>
    </Style>

观察一下不难发现，所有的这些Content Value全是Unicode字符串。这些都很简单。在之前的开发中，我遇到的一个问题就是默认创建的这些Style太少满足不了整个App的需求，需要一些其他的图标如倾斜、下划线等等，可是，从哪儿去找这些图标对应的Unicode编码呢？
按快捷键Win+R，输入charmap.exe，打开字符映射表，将字体选择为Segoe UI Symbol，然后将内容的滚动条滑动到偏下的位置（常用的图标为E开头的），如图，选择需要的图标，在窗口左下角就会显示出该图标对应的Unicode编码。