在WPF窗口StateChanging事件

本文介绍了在WPF窗口StateChanging事件的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我需要处理的WPF应用程序的权利之前，它会最小化，而不是当它已经存在。 我发现Window对象StateChanged，但它触发时，Window对象是已经在最小化状态，那么一切都太迟了。

I need to handle WPF application right before it goes Minimize, not when it's already there. I found on Window object StateChanged, but it fires when Window object is already in Minimize state, then it's too late.

所以，我需要的东西，如StateChanging事件来处理，而Window对象仍处于previous状态。

So, I need something like "StateChanging" event to handle, while Window object is still in previous state.

是否有可能创造这样的事件？

Is it possible to create such event ?

推荐答案

找到Windows消息呼吁窗口右侧前尽量减少使用间谍++。第一个被称为是WM_WINDOWPOSCHANGING。 我不知道窗户上-32000移动窗口时，最大限度地减少寡妇，这些都是在WM_WINDOWPOSCHANGING的PARAMS -32000定位点。虽然，我已经测试只有在Vista上。 blogs.msdn/oldnewthing/archive/2004/10/28/249044.aspx

Found windows messages called on window right before minimize using Spy++. First one that is called is WM_WINDOWPOSCHANGING. I didn't know windows is moving window on -32000, -32000 location point when minimizing widow, and those were the params in WM_WINDOWPOSCHANGING. Though, I have tested is only on Vista. blogs.msdn/oldnewthing/archive/2004/10/28/249044.aspx

这里使用code被张贴由尼尔here

code used here was posted by Nir here

下面是示例code

XAML

<Window x:Class="WindowStateTest2.Window1" xmlns="schemas.microsoft/winfx/2006/xaml/presentation" xmlns:x="schemas.microsoft/winfx/2006/xaml" Title="Window1" Height="300" Width="300"> <Grid> <Grid.RowDefinitions> <RowDefinition Height="Auto"></RowDefinition> <RowDefinition Height="*"></RowDefinition> </Grid.RowDefinitions> <Button Click="btnClear_Click" Grid.Row="0" x:Name="btnClear">Clear</Button> <TextBox Name="txt" VerticalScrollBarVisibility="Visible" Grid.Row="2"></TextBox> </Grid> </Window>

C＃

using System; using System.Collections.Generic; using System.Linq; using System.Text; 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; using System.Windows.Interop; using System.Runtime.InteropServices; namespace WindowStateTest2 { /// <summary> /// Interaction logic for Window1.xaml /// </summary> public partial class Window1 : Window { public Window1() { InitializeComponent(); this.StateChanged += new EventHandler(Window1_StateChanged); this.SourceInitialized += new EventHandler(Window1_SourceInitialized); } #region Event handlers void btnClear_Click(object sender, RoutedEventArgs e) { this.txt.Text = string.Empty; } void Window1_SourceInitialized(object sender, EventArgs e) { AttachWndProc(); } void Window1_StateChanged(object sender, EventArgs e) { if (this.WindowState == WindowState.Minimized) Console.WriteLine("SC: " + this.WindowState); } #endregion #region Const private int SYSCOMMAND = 0x0112; private int SC_MINIMIZE = 0xf020; private int WINDOWPOSCHANGING = 0x0046; #endregion private void AttachWndProc() { HwndSource source = HwndSource.FromHwnd(new WindowInteropHelper(this).Handle); source.AddHook(new HwndSourceHook(WndProc)); } [StructLayout(LayoutKind.Sequential)] internal struct WINDOWPOSPARAMS { public IntPtr hwnd; public IntPtr hwndInsertAfter; public int x; public int y; public int cx; public int cy; public int flags; } private IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, IntPtr lParam, ref bool handled) { if (msg == WINDOWPOSCHANGING) { WINDOWPOSPARAMS param = (WINDOWPOSPARAMS)Marshal.PtrToStructure(lParam, typeof(WINDOWPOSPARAMS)); if (param.x == -32000 && param.y == -32000) { Output(""); // EVENT WOULD BE RAISED HERE Output("State before minimize:"); Output(string.Format("CurrentState: {0}", this.WindowState)); Output(string.Format("Location {0} {1}: ", this.Top, this.Left)); Output(""); } } // process minimize button if (msg == SYSCOMMAND && SC_MINIMIZE == wParam.ToInt32()) { Output("Minimize clicked"); } handled = false; return IntPtr.Zero; } public void Output(object output) { this.txt.Text += output.ToString(); this.txt.Text += Environment.NewLine; } } }