重新想象 Windows 8 Store Apps (9) - 控件之 ScrollViewer 基础

原文:重新想象 Windows 8 Store Apps (9) - 控件之 ScrollViewer 基础[源码下载]

[align=center]重新想象 Windows 8 Store Apps (9) - 控件之 ScrollViewer 基础[/align]

作者：webabcd

介绍
重新想象 Windows 8 Store Apps 之 ScrollViewer

演示 ScrollViewer 的基本应用

演示 ScrollBar 的基本应用

演示 ScrollContentPresenter 的基本应用

示例
1、ScrollViewer 的基本应用
ScrollViewer/Demo.xaml

<Page
x:Class="XamlDemo.Controls.ScrollViewer.Demo"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:XamlDemo.Controls.ScrollViewer"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d">

<Grid Background="Transparent">
<StackPanel Margin="120 0 0 0">

<TextBlock Name="lblMsg" />

<!--
ScrollViewer - 滚动视图控件
Content - 滚动视图内的内容
IsDeferredScrollingEnabled - 是否启用延迟滚动，在滚动内容过多时，启用延迟混动可以改善性能，默认值为 false
HorizontalScrollMode - 水平滚动条的行为方式，Windows.UI.Xaml.Controls.ScrollMode枚举（Disabled, Enabled, Auto）
VerticalScrollMode - 垂直滚动条的行为方式
HorizontalScrollBarVisibility - 水平滚动条的可见性，Windows.UI.Xaml.Controls.ScrollBarVisibility枚举（Disabled, Auto, Hidden, Visible）
VerticalScrollBarVisibility - 垂直滚动条的可见性
ViewChanged - 发生滚动时所触发的事件
-->
<ScrollViewer Name="scrollViewer" Width="400" Height="400" Margin="0 10 0 0" HorizontalAlignment="Left"
IsDeferredScrollingEnabled="False"
ViewChanged="scrollViewer_ViewChanged_1"
HorizontalScrollMode="Enabled" VerticalScrollMode="Enabled"
HorizontalScrollBarVisibility="Visible" VerticalScrollBarVisibility="Visible">
<ScrollViewer.Content>
<Image Source="/Assets/Logo.png" Width="1000" />
</ScrollViewer.Content>
</ScrollViewer>

<StackPanel Orientation="Horizontal">
<!--使 ScrollViewer 里的内容滚动到相对于 ScrollViewer 居中-->
<Button Content="居中" Click="Button_Click_1" />
</StackPanel>

</StackPanel>
</Grid>
</Page>

ScrollViewer/Demo.xaml.cs

/*
* ScrollViewer - 滚动视图控件
*
* 本例用于演示 ScrollViewer 的基本用法
*/

using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;

namespace XamlDemo.Controls.ScrollViewer
{
public sealed partial class Demo : Page
{
public Demo()
{
this.InitializeComponent();
}

private void scrollViewer_ViewChanged_1(object sender, ScrollViewerViewChangedEventArgs e)
{
lblMsg.Text = "";

/*
* ScrollViewer - 滚动视图控件
*     ComputedHorizontalScrollBarVisibility - 当前水平滚动条的可见性，比如当 HorizontalScrollBarVisibility 设置为 Auton 时，可以通过 ComputedHorizontalScrollBarVisibility 来判断当前水平滚动条是否可见
*     ComputedVerticalScrollBarVisibility - 当前垂直滚动条的可见性
*     ExtentWidth - ScrollViewer 内的内容的宽
*     ExtentHeight - ScrollViewer 内的内容的高
*     ViewportWidth - 可视区的宽
*     ViewportHeight - 可视区的高
*     HorizontalOffset - 滚动内容的水平方向的偏移量
*     VerticalOffset - 滚动内容的垂直方向的偏移量
*     ScrollableWidth - 可滚动区域的水平方向的大小
*     ScrollableHeight - 可滚动区域的垂直方向的大小
*
*     ScrollToHorizontalOffset() - 滚动到指定的水平偏移位置
*     ScrollToVerticalOffset() - 滚动到指定的垂直偏移位置
*/

lblMsg.Text += "ComputedHorizontalScrollBarVisibility: " + scrollViewer.ComputedHorizontalScrollBarVisibility;
lblMsg.Text += "\r\n";
lblMsg.Text += "ComputedVerticalScrollBarVisibility: " + scrollViewer.ComputedVerticalScrollBarVisibility;
lblMsg.Text += "\r\n";
lblMsg.Text += "ExtentWidth: " + scrollViewer.ExtentWidth;
lblMsg.Text += "\r\n";
lblMsg.Text += "ExtentHeight: " + scrollViewer.ExtentHeight;
lblMsg.Text += "\r\n";
lblMsg.Text += "ViewportWidth: " + scrollViewer.ViewportWidth;
lblMsg.Text += "\r\n";
lblMsg.Text += "ViewportHeight: " + scrollViewer.ViewportHeight;
lblMsg.Text += "\r\n";
lblMsg.Text += "HorizontalOffset: " + scrollViewer.HorizontalOffset;
lblMsg.Text += "\r\n";
lblMsg.Text += "VerticalOffset: " + scrollViewer.VerticalOffset;
lblMsg.Text += "\r\n";
lblMsg.Text += "ScrollableWidth: " + scrollViewer.ScrollableWidth;
lblMsg.Text += "\r\n";
lblMsg.Text += "ScrollableHeight: " + scrollViewer.ScrollableHeight;
lblMsg.Text += "\r\n";
}

private void Button_Click_1(object sender, RoutedEventArgs e)
{
scrollViewer.ScrollToHorizontalOffset(scrollViewer.ScrollableWidth / 2);
scrollViewer.ScrollToVerticalOffset(scrollViewer.ScrollableHeight / 2);
}
}
}

2、ScrollBar 的基本应用
ScrollViewer/ScrollBarDemo.xaml

<Page
x:Class="XamlDemo.Controls.ScrollViewer.ScrollBarDemo"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:XamlDemo.Controls.ScrollViewer"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d">

<Grid Background="Transparent">
<StackPanel Margin="120,0,0,0">

<TextBlock Name="lblMsg" FontSize="14.667" HorizontalAlignment="Left" />
<ScrollViewer Name="scrollViewer" Width="400" Height="200" HorizontalAlignment="Left">
<Image Source="/Assets/Logo.png" Width="1000" />
</ScrollViewer>

</StackPanel>
</Grid>
</Page>

ScrollViewer/ScrollBarDemo.xaml.cs

/*
* ScrollBar - 滚动条控件
*
* 本例通过访问 ScrollViewer 内的名为 VerticalScrollBar 的 ScrollBar 控件，来简要说明 ScrollBar 控件
*/

using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using Windows.UI.Xaml.Controls.Primitives;
using XamlDemo.Common;

namespace XamlDemo.Controls.ScrollViewer
{
public sealed partial class ScrollBarDemo : Page
{
public ScrollBarDemo()
{
this.InitializeComponent();

this.Loaded += ScrollBarDemo_Loaded;
}

void ScrollBarDemo_Loaded(object sender, RoutedEventArgs e)
{
// 找到 ScrollViewer 内的名为 VerticalScrollBar 的 ScrollBar 控件，即 ScrollViewer 内的垂直滚动条
var scrollBar = Helper.GetVisualChild<ScrollBar>(scrollViewer, "VerticalScrollBar");
// ValueChanged - 当滚动条的值发生改变是所触发的事件
scrollBar.ValueChanged += scrollBar_ValueChanged;
}

void scrollBar_ValueChanged(object sender, RangeBaseValueChangedEventArgs e)
{
// 显示垂直滚动条的当前值
lblMsg.Text = e.NewValue.ToString();
}
}
}

3、ScrollContentPresenter 的基本应用
ScrollViewer/ScrollContentPresenterDemo.xaml

<Page
x:Class="XamlDemo.Controls.ScrollViewer.ScrollContentPresenterDemo"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
xmlns:local="using:XamlDemo.Controls.ScrollViewer"
xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
mc:Ignorable="d">

<Grid Background="Transparent">
<StackPanel Margin="120 0 0 0">

<ScrollViewer Name="scrollViewer" Width="400" Height="400" Background="Blue" HorizontalAlignment="Left"
HorizontalScrollMode="Enabled" VerticalScrollMode="Enabled"
HorizontalScrollBarVisibility="Visible" VerticalScrollBarVisibility="Visible">
<ScrollViewer.Content>
<Image Source="/Assets/Logo.png" Width="1000" />
</ScrollViewer.Content>
</ScrollViewer>

</StackPanel>
</Grid>
</Page>

ScrollViewer/ScrollContentPresenterDemo.xaml.cs

/*
* ScrollContentPresenter - ScrollViewer 的内容呈现器（类似的有 ContentPresenter, ItemsPresenter）
*
* ScrollContentPresenter 用来呈现 ScrollViewer 的 Content
*/

using Windows.UI.Xaml;
using Windows.UI.Xaml.Controls;
using XamlDemo.Common;

namespace XamlDemo.Controls.ScrollViewer
{
public sealed partial class ScrollContentPresenterDemo : Page
{
public ScrollContentPresenterDemo()
{
this.InitializeComponent();

this.Loaded += ScrollContentPresenterDemo_Loaded;
}

void ScrollContentPresenterDemo_Loaded(object sender, RoutedEventArgs e)
{
// 找到 ScrollViewer 内的名为 ScrollContentPresenter 的 ScrollContentPresenter 控件
var scrollContentPresenter = Helper.GetVisualChild<ScrollContentPresenter>(scrollViewer, "ScrollContentPresenter");

scrollContentPresenter.Margin = new Thickness(100);
}
}
}

OK
[源码下载]