C# WPF后台动态加控件
zls366 人气:0概述
在Winform中从后台添加控件相对比较容易,但是在WPF中,我们知道界面是通过XAML编写的,如何把后台写好的控件动态添加到前台呢?本节举例介绍这个问题。
这里要用到UniformGrid布局,UniformGrid 是一种横向的网格分割、纵向的网格分割分别是均等的分割的布局类型.
项目介绍
-. 这里界面添加一个ComboBox用来下拉选择图片数量;
-. 添加一个button用来执行图片显示;
dispaly下方是图片显示区域
代码设计
-.前台XAML代码:
<Grid> <dxlc:LayoutControl Orientation="Vertical"> <dxlc:LayoutGroup Orientation="Horizontal" View="GroupBox"> <dxlc:LayoutGroup.Header> <dxlc:LayoutItem Label="Action" Background="#FF004486" Foreground="White"/> </dxlc:LayoutGroup.Header> <dxlc:LayoutItem Label="Image Count" > <ComboBox SelectedIndex="{Binding ComSelectedIndex}"> <ComboBoxItem>2</ComboBoxItem> <ComboBoxItem>4</ComboBoxItem> <ComboBoxItem>6</ComboBoxItem> </ComboBox> </dxlc:LayoutItem> <dxlc:LayoutItem Width="110"> <dx:SimpleButton Content="Image Dispaly" Background="LightGray" cal:Message.Attach="[Event Click]=[btnAdd_Click($source,$eventArgs)]" /> </dxlc:LayoutItem> </dxlc:LayoutGroup> <dxlc:LayoutGroup Orientation="Horizontal" View="GroupBox"> <dxlc:LayoutGroup.Header> <dxlc:LayoutItem Label="Dispaly" Background="#FF004486" Foreground="White"/> </dxlc:LayoutGroup.Header> <UniformGrid cal:Message.Attach="[Event Loaded]=[UniformGrid_Loaded($source,$eventArgs)]" /> </dxlc:LayoutGroup> </dxlc:LayoutControl> </Grid>
前台代码比较简单,只要关注下UniformGrid控件,绑定了Loaded事件。
-.后台代码:
[AddINotifyPropertyChangedInterface] public class UniformGridViewModel : Screen, IViewModel { public int ComSelectedIndex { get; set; } public UniformGrid UniformGrid; public string[] ImageFullPath; public void btnAdd_Click(object sender, RoutedEventArgs e) { UniformGrid.Children.Clear(); UniformGrid.Columns = 2; var count = 0; switch(ComSelectedIndex) { case 0: count = 2;break; case 1: count = 4; break; case 2: count = 6; break; default: break; } for (int i = 0; i < count; i++) { Image image = new Image(); image.Source = LoadImageFreeze(ImageFullPath[i]); image.MouseLeftButtonUp += ImageClick; image.Name = Path.GetFileNameWithoutExtension(ImageFullPath[i]); image.Margin = new Thickness(5); UniformGrid.Children.Add(image); } } public void ImageClick(object sender, MouseButtonEventArgs e) { var name = (sender as Image).Name; MessageBox.Show($"当前选择的图片名称:{name}"); } public void UniformGrid_Loaded(object sender, RoutedEventArgs e) { UniformGrid = (UniformGrid)sender; } public UniformGridViewModel() { DisplayName = "UniformGrid"; string imagePath =Path.Combine( AppDomain.CurrentDomain.BaseDirectory, "Images"); ImageFullPath = Directory.GetFiles(imagePath, "*.png"); } public static BitmapImage LoadImageFreeze(string imagePath) { try { var bitmap = new BitmapImage(); if (File.Exists(imagePath)) { bitmap.BeginInit(); bitmap.CacheOption = BitmapCacheOption.OnLoad; using (Stream ms = new MemoryStream(File.ReadAllBytes(imagePath))) { bitmap.StreamSource = ms; bitmap.EndInit(); bitmap.Freeze(); } } return bitmap; } catch (Exception) { return null; } } }
介绍:
①LoadImageFreeze:从路径下加载图片并转换为BitmapImage;
②UniformGrid_Loaded;获取UniformGrid对象;
③ImageFullPath:从项目bin下获取图片文件并读取到这个数组;
④btnAdd_Click:界面button点击事件,这里是核心的代码,主要就是申城图片,然后设定好 UniformGrid的行列以及其他属性后添加到控件里面, UniformGrid.Children.Add(image);
⑤ImageClick:点击后显示图片的名称.
源码
总结
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