<Window x:Class="WpfApp108.MainWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:behavior="http://schemas.microsoft.com/xaml/behaviors" xmlns:local="clr-namespace:WpfApp108" mc:Ignorable="d" WindowState="Maximized" Title="{Binding SelectedItem,ElementName=lbx}" Height="450" Width="800"> <Grid> <Grid.ColumnDefinitions> <ColumnDefinition Width="200"/> <ColumnDefinition/> </Grid.ColumnDefinitions> <ListBox Grid.Column="0" x:Name="lbx" SelectedIndex="0" ItemsSource="{Binding ImgsList,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}" > <behavior:Interaction.Triggers> <behavior:EventTrigger EventName="SelectionChanged"> <behavior:CallMethodAction TargetObject="{Binding}" MethodName="lbx_SelectionChanged" /> </behavior:EventTrigger> </behavior:Interaction.Triggers> <ListBox.ItemTemplate> <DataTemplate> <Viewbox Width="200" Height="200"> <Image Source="{Binding Content,RelativeSource={RelativeSource AncestorType=ListBoxItem}}"/> </Viewbox> </DataTemplate> </ListBox.ItemTemplate> </ListBox> <Image Grid.Column="1" Source="{Binding SelectedItem,ElementName=lbx}" Stretch="Uniform" RenderOptions.BitmapScalingMode="HighQuality" > <behavior:Interaction.Triggers> <behavior:EventTrigger EventName="MouseWheel"> <behavior:CallMethodAction TargetObject="{Binding}" MethodName="Image_MouseWheel"/> </behavior:EventTrigger> </behavior:Interaction.Triggers> <Image.RenderTransform> <ScaleTransform ScaleX="{Binding ScaleLevel,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}" ScaleY="{Binding ScaleLevel,Mode=TwoWay,UpdateSourceTrigger=PropertyChanged}" /> </Image.RenderTransform> </Image> </Grid> </Window> //xaml.cs using System; using System.Collections.Generic; using System.Collections.ObjectModel; using System.ComponentModel; using System.Linq; using System.Security; using System.Text; using System.Threading.Tasks; using System.Windows; using System.Windows.Controls; using System.Windows.Data; using System.Windows.Documents; using System.Windows.Input; using System.Windows.Media; using System.Windows.Media.Imaging; using System.Windows.Navigation; using System.Windows.Shapes; namespace WpfApp108 { /// <summary> /// Interaction logic for MainWindow.xaml /// </summary> public partial class MainWindow : Window { public MainWindow() { InitializeComponent(); var vm = new MainVM(); this.DataContext= vm; } } public class MainVM:INotifyPropertyChanged { public event PropertyChangedEventHandler PropertyChanged; private void OnPropertyChanged(string propertyName) { var handler= PropertyChanged; if (handler != null) { handler?.Invoke(this, new PropertyChangedEventArgs(propertyName)); } } #region Properties private double scaleLevel = 1.0; public double ScaleLevel { get { return scaleLevel; } set { if(value!=scaleLevel) { scaleLevel = value; OnPropertyChanged(nameof(ScaleLevel)); } } } private ObservableCollection<string> imgsList; public ObservableCollection<string> ImgsList { get { return imgsList; } set { if(value!=imgsList) { imgsList = value; OnPropertyChanged(nameof(ImgsList)); } } } #endregion #region Commands Methods public MainVM() { InitData(); } private void InitData() { string dir = @"..\..\Images"; string fullDir = System.IO.Path.GetFullPath(dir); if(System.IO.Directory.Exists(fullDir)) { var allFiles=System.IO.Directory.GetFiles(fullDir); ImgsList = new ObservableCollection<string>(allFiles); } } public void Image_MouseWheel(object sender, MouseWheelEventArgs e) { if (e.Delta > 0) { ScaleLevel *= 1.2; } else { ScaleLevel /= 1.2; } } public void lbx_SelectionChanged(object sender, SelectionChangedEventArgs e) { } #endregion } public class DelCmd : ICommand { public event EventHandler CanExecuteChanged; protected void RaiseCanExecuteChanged() { var handler = CanExecuteChanged; if (handler != null) { handler?.Invoke(this, EventArgs.Empty); } } private Action<object> _execute; private Predicate<object> _canExecute; public DelCmd(Action<object> _executeValue, Predicate<object> _canExecuteValue) { _execute = _executeValue; _canExecute = _canExecuteValue; } public DelCmd(Action<object> _executeValue) : this(_executeValue, null) { } public bool CanExecute(object parameter) { if (_canExecute == null) { return true; } return _canExecute(parameter); } public void Execute(object parameter) { _execute(parameter); } } }
标签:CallMethodAction,thumbnails,mvvm,Windows,void,System,private,using,public From: https://www.cnblogs.com/Fred1987/p/18206162