在 wpf c# 中解决动态创建的内容

Address dynamic created content in wpf c#

我正在为学习目的创建一个动态 GUI。单击“+”按钮后,用户可以添加 itemControl 模板。

通过动态创建元素的名称(在本例中 x:Name="lblName" 应该可用但必须先构建)获取元素的最佳做法是什么?

MainWindow.xaml:

    <ItemsControl Name="icDynamicTableColumn">
        <ItemsControl.ItemTemplate>
            <DataTemplate>
                <Grid Margin="0,0,0,5">
                    <StackPanel>
                        <TextBlock Text="{Binding Description}" Height="23" Width="auto" VerticalAlignment="Top" HorizontalAlignment="Left" Margin="5"/>
                        <TextBox x:Name="lblName" Text="{Binding Textfield}" Height="23" VerticalAlignment="Top" HorizontalAlignment="Stretch" Margin="5"/>
                    </StackPanel>
                </Grid>
            </DataTemplate>
        </ItemsControl.ItemTemplate>
    </ItemsControl>

MainWindow.xaml.cs:

public partial class MainWindow : Window
{
        [...]
        public ObservableCollection<DynamicTableColumn> items = new ObservableCollection<DynamicTableColumn>();
        [...]

        public MainWindow() 
        {
                [...]
                InitializeComponent();
                icDynamicTableColumn.ItemsSource = items;
        }

        public class DynamicTableColumn
        {
                public string Description
                {
                        get {
                                return _description;
                        }

                        set {
                                [...]
                        }
                }
                private string _description;
                public string Textfield { get; set; }
        }

}

如果在用户添加新项目或更改文本时做一些操作就足够了,我建议使用事件,例如已加载或已更改文本。

如果确实需要动态查找文本框,可以使用如下代码:

    ObservableCollection<DynamicTableColumn> Collection = new ObservableCollection<DynamicTableColumn>();

    public MainWindow()
    {
        InitializeComponent();
        icDynamicTableColumn.ItemsSource = Collection;

        Loaded += MainWindow_Loaded;
    }

    private StackPanel Panel;

    private void MainWindow_Loaded(object sender, RoutedEventArgs e)
    {
        //find the panel that contains the children
        Panel = (StackPanel)VisualTreeHelper.GetChild(VisualTreeHelper.GetChild(
                 VisualTreeHelper.GetChild(icDynamicTableColumn, 0), 0), 0);
    }

    TextBox GetTextBoxForIndex(int index)
    {
        //get the child for a given index
        var presenter = (ContentPresenter)VisualTreeHelper.GetChild(Panel, index);
        return (TextBox)presenter.ContentTemplate.FindName("lblName", presenter);
    }

    private void ButtonBase_OnClick(object sender, RoutedEventArgs e)
    {
        Collection.Add(new DynamicTableColumn());
        //make sure that the Textbox was loaded
        icDynamicTableColumn.UpdateLayout();

        var textBox = GetTextBoxForIndex(Collection.Count - 1);
    }

请注意,这假定您使用 ItemsControl 并且没有更改它的 (Control)Template。如果您经常需要这样做,您可以创建自己的 ItemsControl(从中派生)并公开 GetTextBoxForIndex 方法。但是,您应该进行一些安全检查(例如,必须加载范围内的索引和演示者)。