我正在查看 VS2012 附带的 windows 8 网格项目并试图理解它。我对 XAML 了解不多,所以我很容易忘记绑定代码发生在哪里等等。
<Page.Resources>
<!--
Collection of grouped items displayed by this page, bound to a subset
of the complete item list because items in groups cannot be virtualized
-->
<CollectionViewSource
x:Name="groupedItemsViewSource"
Source="{Binding Groups}"
IsSourceGrouped="true"
ItemsPath="TopItems"
d:Source="{Binding AllGroups, Source={d:DesignInstance Type=data:SampleDataSource, IsDesignTimeCreatable=True}}"/>
</Page.Resources>
<!--
This grid acts as a root panel for the page that defines two rows:
* Row 0 contains the back button and page title
* Row 1 contains the rest of the page layout
-->
<Grid Style="{StaticResource LayoutRootStyle}">
<Grid.RowDefinitions>
<RowDefinition Height="140"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<!-- Horizontal scrolling grid used in most view states -->
<GridView
x:Name="itemGridView"
AutomationProperties.AutomationId="ItemGridView"
AutomationProperties.Name="Grouped Items"
Grid.RowSpan="2"
Padding="116,137,40,46"
ItemsSource="{Binding Source={StaticResource groupedItemsViewSource}}"
ItemTemplate="{StaticResource Standard250x250ItemTemplate}"
SelectionMode="None"
IsSwipeEnabled="false"
IsItemClickEnabled="True"
ItemClick="ItemView_ItemClick">
<GridView.ItemsPanel>
<ItemsPanelTemplate>
<VirtualizingStackPanel Orientation="Horizontal"/>
</ItemsPanelTemplate>
</GridView.ItemsPanel>
<GridView.GroupStyle>
<GroupStyle>
<GroupStyle.HeaderTemplate>
<DataTemplate>
<Grid Margin="1,0,0,6">
<Button
AutomationProperties.Name="Group Title"
Click="Header_Click"
Style="{StaticResource TextPrimaryButtonStyle}" >
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Title}" Margin="3,-7,10,10" Style="{StaticResource GroupHeaderTextStyle}" />
<TextBlock Text="{StaticResource ChevronGlyph}" FontFamily="Segoe UI Symbol" Margin="0,-7,0,10" Style="{StaticResource GroupHeaderTextStyle}"/>
</StackPanel>
</Button>
</Grid>
</DataTemplate>
</GroupStyle.HeaderTemplate>
<GroupStyle.Panel>
<ItemsPanelTemplate>
<VariableSizedWrapGrid Orientation="Vertical" Margin="0,0,80,0"/>
</ItemsPanelTemplate>
</GroupStyle.Panel>
</GroupStyle>
</GridView.GroupStyle>
</GridView>
<!-- Vertical scrolling list only used when snapped -->
<ListView
x:Name="itemListView"
AutomationProperties.AutomationId="ItemListView"
AutomationProperties.Name="Grouped Items"
Grid.Row="1"
Visibility="Collapsed"
Margin="0,-10,0,0"
Padding="10,0,0,60"
ItemsSource="{Binding Source={StaticResource groupedItemsViewSource}}"
ItemTemplate="{StaticResource Standard80ItemTemplate}"
SelectionMode="None"
IsSwipeEnabled="false"
IsItemClickEnabled="True"
ItemClick="ItemView_ItemClick">
<ListView.GroupStyle>
<GroupStyle>
<GroupStyle.HeaderTemplate>
<DataTemplate>
<Grid Margin="7,7,0,0">
<Button
AutomationProperties.Name="Group Title"
Click="Header_Click"
Style="{StaticResource TextPrimaryButtonStyle}">
<StackPanel Orientation="Horizontal">
<TextBlock Text="{Binding Title}" Margin="3,-7,10,10" Style="{StaticResource GroupHeaderTextStyle}" />
<TextBlock Text="{StaticResource ChevronGlyph}" FontFamily="Segoe UI Symbol" Margin="0,-7,0,10" Style="{StaticResource GroupHeaderTextStyle}"/>
</StackPanel>
</Button>
</Grid>
</DataTemplate>
</GroupStyle.HeaderTemplate>
</GroupStyle>
</ListView.GroupStyle>
</ListView>
<!-- Back button and page title -->
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Button x:Name="backButton" Click="GoBack" IsEnabled="{Binding Frame.CanGoBack, ElementName=pageRoot}" Style="{StaticResource BackButtonStyle}"/>
<TextBlock x:Name="pageTitle" Text="{StaticResource AppName}" Grid.Column="1" IsHitTestVisible="false" Style="{StaticResource PageHeaderTextStyle}"/>
</Grid>
<VisualStateManager.VisualStateGroups>
<!-- Visual states reflect the application's view state -->
<VisualStateGroup x:Name="ApplicationViewStates">
<VisualState x:Name="FullScreenLandscape"/>
<VisualState x:Name="Filled"/>
<!-- The entire page respects the narrower 100-pixel margin convention for portrait -->
<VisualState x:Name="FullScreenPortrait">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="backButton" Storyboard.TargetProperty="Style">
<DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource PortraitBackButtonStyle}"/>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="itemGridView" Storyboard.TargetProperty="Padding">
<DiscreteObjectKeyFrame KeyTime="0" Value="96,137,10,56"/>
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<!--
The back button and title have different styles when snapped, and the list representation is substituted
for the grid displayed in all other view states
-->
<VisualState x:Name="Snapped">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="backButton" Storyboard.TargetProperty="Style">
<DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource SnappedBackButtonStyle}"/>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="pageTitle" Storyboard.TargetProperty="Style">
<DiscreteObjectKeyFrame KeyTime="0" Value="{StaticResource SnappedPageHeaderTextStyle}"/>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="itemListView" Storyboard.TargetProperty="Visibility">
<DiscreteObjectKeyFrame KeyTime="0" Value="Visible"/>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetName="itemGridView" Storyboard.TargetProperty="Visibility">
<DiscreteObjectKeyFrame KeyTime="0" Value="Collapsed"/>
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
</Grid>
我不明白的第一个领域是这个
<CollectionViewSource
x:Name="groupedItemsViewSource"
Source="{Binding Groups}"
IsSourceGrouped="true"
ItemsPath="TopItems"
d:Source="{Binding AllGroups, Source={d:DesignInstance Type=data:SampleDataSource, IsDesignTimeCreatable=True}}"/>
我不知道这 Source="{Binding Groups}"
实际上来自哪里(我什至不确定如何找到代码 F12 不起作用)。
与d:Source
不确定 100% 的情况相同。
下一部分是在 gridview 中,然后是绑定。
<GridView
x:Name="itemGridView"
AutomationProperties.AutomationId="ItemGridView"
AutomationProperties.Name="Grouped Items"
Grid.RowSpan="2"
Padding="116,137,40,46"
ItemsSource="{Binding Source={StaticResource groupedItemsViewSource}}"
ItemTemplate="{StaticResource Standard250x250ItemTemplate}"
SelectionMode="None"
IsSwipeEnabled="false"
IsItemClickEnabled="True"
ItemClick="ItemView_ItemClick">
我看到 Items Source 正在使用该 groupItemsViewSource 但不确定它如何将数据解析为网格外观但不确定如何。
我不明白的下一部分是它如何确定要使用的布局。我在评论中看到了这个
<!-- Horizontal scrolling grid used in most view states -->
<!-- Vertical scrolling list only used when snapped -->
我敢肯定,如果我更深入地研究它,我会发现更多我不理解的东西,但也许当我理解这些东西时,我会理解更多(尤其是一旦我理解了这些绑定的东西)