Question

问题：如何在C＃中使用Grid布局制作ItemsWrapGrid？

上下文

UWP
Visual Studio 2015
Windows 10
C＃

背景

我知道如何在XAML中制作它。在Visual Studio 2015中创建新的UWP应用程序后，XAML为：

<Page
    x:Class="WrapGridTest001.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:WrapGridTest001"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    MinWidth="10"
    MinHeight="10"
    >

    <Grid x:Name="thisGrid">
        <GridView x:Name="thisGridView" IsItemClickEnabled="True">
            <GridView.ItemsPanel>
                <ItemsPanelTemplate>
                    <ItemsWrapGrid
                            x:Name="thisItemsWrapGrid"
                            Orientation="Horizontal"
                            MaximumRowsOrColumns="5"
                        />
                </ItemsPanelTemplate>
            </GridView.ItemsPanel>
            <TextBlock Text="#1"/>
            <TextBlock Text="#2"/>
            <TextBlock Text="#3"/>
        </GridView>
    </Grid>
</Page>

为了以编程方式进行，我已将其从XAML中删除：

<Page
    x:Class="WrapGridTest001.MainPage"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:WrapGridTest001"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d"
    MinWidth="10"
    MinHeight="10"
    >
</Page>

并尝试在Page的构造函数中重现它：

public MainPage()
{
    this.InitializeComponent();

    // Make the Grid and set it to be the Page's .Content:
    Grid grid = new Grid();
    this.Content = grid;

    // Make the GridView for the Grid, then set it:
    GridView gridView = new GridView();
    grid.Children.Add(gridView);

    // Make the ItemsPanelTemplate; necessary?
    ItemsPanelTemplate itemsPanelTemplate = new ItemsPanelTemplate();
    gridView.ItemsPanel = itemsPanelTemplate;

    // Make the ItemsWrapGrid.  Can't figure out how to set this.
    ItemsWrapGrid itemsWrapGrid = new ItemsWrapGrid();
    // When I traced the XAML version, its ItemsWrapGrid was apparently under
    //      gridView.ItemsPanelRoot
    // , but that's a get-only property.  I can't find a place to set it.

    // Add the TextBlock's with "#1", "#2", and "#3":
    for (int i = 1; i <= 3; ++i)
    {
        TextBlock textBlock = new TextBlock();
        textBlock.Text = "#" + i.ToString();
        gridView.Items.Add(textBlock);
    }

    // All done.  However, this Grid will show contents with a vertical alignment
    // rather than a horizontal one.
}

我需要添加哪些附加代码才能在C＃中设置ItemsWrapGrid，因为它是在XAML中设置的？目前，C＃代码会创建ItemsWrapGrid，但ItemsWrapGrid实际上并未在任何位置设置，因为到目前为止每次尝试使用它都会导致某种错误。

Answer 1

你需要的是XamlReader

string template =
                "<ItemsPanelTemplate xmlns=\"http://schemas.microsoft.com/winfx/2006/xaml/presentation\" xmlns:x=\"http://schemas.microsoft.com/winfx/2006/xaml\"><ItemsWrapGrid VerticalAlignment = \"Top\" "
                + " ItemWidth = \""
                + itemWidth
                + "\" Orientation = \"Horizontal\"/></ItemsPanelTemplate> ";
yourgridview.ItemsPanel = (ItemsPanelTemplate)XamlReader.Load(template);

Answer 2

事实是ItemsWrapGrid是GridView的默认面板。 ItemsPanelTemplate不能通过属性拥有ItemsWrapGrid并使用XamlReader是不好的。加载gridview后，它会在ItemsPanelRoot获取一个默认的ItemsWrapGrid。

yourgridview.Loaded += yourgridview_Loaded;

和功能

private void yourgridview_Loaded(object sender, RoutedEventArgs e)
{
    var a = sender as GridView;
    var b = a.ItemsPanelRoot;
    var c = b as ItemsWrapGrid;
    c.MaximumRowsOrColumns = 2;c.Orientation = Orientation.Horizontal;
}

如何使用C＃在UWP中创建ItemsWrapGrid？

2 个答案: