UWP 以编程方式添加自定义控件:数据未显示

UWP programmatically adding custom controls: data not showing

我在我的 UWP 应用程序中创建了一个名为 ItemControl 的自定义控件。

控件的XAML:

<UserControl
    x:Class="UniBL.ItemControl"
    xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
    xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
    xmlns:local="using:UniBL"
    xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
    xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
    mc:Ignorable="d" Height="283.385" Width="430.462">

    <Grid Margin="0,0,-34,0.333">
        <TextBox x:Name="textBox" HorizontalAlignment="Left" Margin="0,10,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="235" Foreground="#FF3868E6" BorderThickness="0" IsTabStop="False" Background="{x:Null}"/>
        <TextBox x:Name="textBox_status" HorizontalAlignment="Left" Margin="0,39,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="109" Foreground="#FF3868E6" BorderThickness="1,0" IsTabStop="False" Background="{x:Null}" BorderBrush="#FFDAD9D9" Height="32"/>
        <TextBox x:Name="textBox_type" HorizontalAlignment="Left" Margin="126,39,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="109" Foreground="#FF3868E6" BorderThickness="1,0" IsTabStop="False" Background="{x:Null}" BorderBrush="#FFDAD9D9"/>
        <TextBox x:Name="textBox_name" HorizontalAlignment="Left" Margin="250,39,0,0" TextWrapping="Wrap" VerticalAlignment="Top" Width="109" Foreground="#FF3868E6" BorderThickness="1,0" IsTabStop="False" Background="{x:Null}" BorderBrush="#FFDAD9D9"/>
        <TextBox x:Name="textBox1" HorizontalAlignment="Left" Margin="9,76,0,0" TextWrapping="Wrap" Text="Item Details" VerticalAlignment="Top" Background="#66C9D6CA" IsTabStop="False"/>
        <StackPanel HorizontalAlignment="Left" Height="160" Margin="10,113,0,0" VerticalAlignment="Top" Width="414" BorderThickness="1" BorderBrush="#FFB2AAAA">
            <TextBox x:Name="textBox2" TextWrapping="Wrap"/>
            <TextBox x:Name="textBox3" TextWrapping="Wrap"/>
            <TextBox x:Name="textBox4" TextWrapping="Wrap"/>
            <TextBox x:Name="textBox5" TextWrapping="Wrap"/>
            <TextBox x:Name="textBox6" TextWrapping="Wrap"/>
        </StackPanel>
    </Grid>
</UserControl>

构造函数:

public ItemControl(Item item)
{
     this.InitializeComponent();

     textBox = new TextBox() { Text = item.itemName };
     textBox_status = new TextBox() { Text = item.itemStatus };
     textBox_type = new TextBox() { Text = item.itemType };
     textBox_name = new TextBox() { Text = item.itemName };
     textBox1 = new TextBox() { Text = "Item Details" };
     textBox2 = new TextBox() { Text = "Inventory number: " + item.inventoryNumber };
     textBox3 = new TextBox() { Text = "Purchase date: " + item.purchaseDate };
     textBox4 = new TextBox() { Text = "Purchase value: " + item.purchaseValue };
     textBox5 = new TextBox() { Text = "Location: " + item.locationId };
     textBox6 = new TextBox() { Text = "Person in charge: " + item.personId };
}

我正在以编程方式将这些控件添加到 Items 页面上的堆栈面板,如下所示:

public Items()
{
     ...
     List<Item> items = Item.ReadItems(); //the data is loaded correctly
     foreach (Item item in items)
            isp.Children.Add(new ItemControl(item));
     isp.UpdateLayout();
}

但是,当我 运行 我的应用程序时,项目控件显示为空白文本框。

您的代码创建了一堆控件,将它们分配给成员变量,但没有将它们添加到父控件中。父控件也已经存在,因此无需创建新控件。

您很可能想为现有值赋值,如下所示:

public ItemControl(Item item)
{
  this.InitializeComponent();

  textBox.Text = item.itemName;
  ...
}