c# - 你如何在 WPF 中进行 AppBar 对接(到屏幕边缘，如 WinAmp)？

Question

有没有关于在 WPF 中进行 AppBar 停靠(例如锁定到屏幕边缘)的完整指南？我知道需要进行 InterOp 调用，但我正在寻找基于简单 WPF 表单的概念证明，或者可以使用的组件化版本。

相关资源:

• http://www.codeproject.com/KB/dotnet/AppBar.aspx
• http://social.msdn.microsoft.com/Forums/en-US/wpf/thread/05c73c9c-e85d-4ecd-b9b6-4c714a65e72b/

Answer 1

请注意:这个问题收集了大量的反馈，下面的一些人提出了很好的观点或修正。因此，虽然我会将代码保留在这里(并可能对其进行更新)，但我还创建了一个 WpfAppBar project on github 。随时发送请求请求。

同一个项目也构建为 WpfAppBar nuget package

---

我从问题中提供的第一个链接 (http://www.codeproject.com/KB/dotnet/AppBar.aspx) 中获取代码并修改它以执行两件事:

1. 使用 WPF
2. “独立”- 如果将这个单个文件放入项目中，则无需对窗口进行任何进一步修改即可调用 AppBarFunctions.SetAppBar(...)。

此方法不创建基类。

要使用，只需从普通 wpf 窗口中的任何位置调用此代码(比如单击按钮或初始化)。请注意，在窗口初始化之后才能调用它，如果尚未创建 HWND(如在构造函数中)，则会发生错误。

使窗口成为应用栏:

AppBarFunctions.SetAppBar( this, ABEdge.Right );

将窗口恢复为普通窗口:

AppBarFunctions.SetAppBar( this, ABEdge.None );

这是文件的完整代码 - 注意您需要将第 7 行的命名空间更改为适当的名称。

using System;
using System.Collections.Generic;
using System.Runtime.InteropServices;
using System.Windows;
using System.Windows.Interop;
using System.Windows.Threading;

namespace AppBarApplication
{    
    public enum ABEdge : int
    {
        Left = 0,
        Top,
        Right,
        Bottom,
        None
    }

    internal static class AppBarFunctions
    {
        [StructLayout(LayoutKind.Sequential)]
        private struct RECT
        {
            public int left;
            public int top;
            public int right;
            public int bottom;
        }

        [StructLayout(LayoutKind.Sequential)]
        private struct APPBARDATA
        {
            public int cbSize;
            public IntPtr hWnd;
            public int uCallbackMessage;
            public int uEdge;
            public RECT rc;
            public IntPtr lParam;
        }

        private enum ABMsg : int
        {
            ABM_NEW = 0,
            ABM_REMOVE,
            ABM_QUERYPOS,
            ABM_SETPOS,
            ABM_GETSTATE,
            ABM_GETTASKBARPOS,
            ABM_ACTIVATE,
            ABM_GETAUTOHIDEBAR,
            ABM_SETAUTOHIDEBAR,
            ABM_WINDOWPOSCHANGED,
            ABM_SETSTATE
        }
        private enum ABNotify : int
        {
            ABN_STATECHANGE = 0,
            ABN_POSCHANGED,
            ABN_FULLSCREENAPP,
            ABN_WINDOWARRANGE
        }

        [DllImport("SHELL32", CallingConvention = CallingConvention.StdCall)]
        private static extern uint SHAppBarMessage(int dwMessage, ref APPBARDATA pData);

        [DllImport("User32.dll", CharSet = CharSet.Auto)]
        private static extern int RegisterWindowMessage(string msg);

        private class RegisterInfo
        {
            public int CallbackId { get; set; }
            public bool IsRegistered { get; set; }
            public Window Window { get; set; }
            public ABEdge Edge { get; set; }
            public WindowStyle OriginalStyle { get; set; }            
            public Point OriginalPosition { get; set; }
            public Size OriginalSize { get; set; }
            public ResizeMode OriginalResizeMode { get; set; }


            public IntPtr WndProc(IntPtr hwnd, int msg, IntPtr wParam, 
                                    IntPtr lParam, ref bool handled)
            {
                if (msg == CallbackId)
                {
                    if (wParam.ToInt32() == (int)ABNotify.ABN_POSCHANGED)
                    {
                        ABSetPos(Edge, Window);
                        handled = true;
                    }
                }
                return IntPtr.Zero;
            }

        }
        private static Dictionary<Window, RegisterInfo> s_RegisteredWindowInfo 
            = new Dictionary<Window, RegisterInfo>();
        private static RegisterInfo GetRegisterInfo(Window appbarWindow)
        {
            RegisterInfo reg;
            if( s_RegisteredWindowInfo.ContainsKey(appbarWindow))
            {
                reg = s_RegisteredWindowInfo[appbarWindow];
            }
            else
            {
                reg = new RegisterInfo()
                    {
                        CallbackId = 0,
                        Window = appbarWindow,
                        IsRegistered = false,
                        Edge = ABEdge.Top,
                        OriginalStyle = appbarWindow.WindowStyle,                        
                        OriginalPosition =new Point( appbarWindow.Left, appbarWindow.Top),
                        OriginalSize = 
                            new Size( appbarWindow.ActualWidth, appbarWindow.ActualHeight),
                        OriginalResizeMode = appbarWindow.ResizeMode,
                    };
                s_RegisteredWindowInfo.Add(appbarWindow, reg);
            }
            return reg;
        }

        private static void RestoreWindow(Window appbarWindow)
        {
            RegisterInfo info = GetRegisterInfo(appbarWindow);

            appbarWindow.WindowStyle = info.OriginalStyle;            
            appbarWindow.ResizeMode = info.OriginalResizeMode;
            appbarWindow.Topmost = false;

            Rect rect = new Rect(info.OriginalPosition.X, info.OriginalPosition.Y, 
                info.OriginalSize.Width, info.OriginalSize.Height);
            appbarWindow.Dispatcher.BeginInvoke(DispatcherPriority.ApplicationIdle,
                    new ResizeDelegate(DoResize), appbarWindow, rect);

        }

        public static void SetAppBar(Window appbarWindow, ABEdge edge)
        {
            RegisterInfo info = GetRegisterInfo(appbarWindow);
            info.Edge = edge;

            APPBARDATA abd = new APPBARDATA();
            abd.cbSize = Marshal.SizeOf(abd);
            abd.hWnd = new WindowInteropHelper(appbarWindow).Handle;

            if( edge == ABEdge.None)
            {
                if( info.IsRegistered)
                {
                    SHAppBarMessage((int)ABMsg.ABM_REMOVE, ref abd);
                    info.IsRegistered = false;
                }
                RestoreWindow(appbarWindow);
                return;
            }

            if (!info.IsRegistered)
            {
                info.IsRegistered = true; 
                info.CallbackId = RegisterWindowMessage("AppBarMessage");
                abd.uCallbackMessage = info.CallbackId;

                uint ret = SHAppBarMessage((int)ABMsg.ABM_NEW, ref abd);

                HwndSource source = HwndSource.FromHwnd(abd.hWnd);
                source.AddHook(new HwndSourceHook(info.WndProc));
            }

            appbarWindow.WindowStyle = WindowStyle.None;            
            appbarWindow.ResizeMode = ResizeMode.NoResize;
            appbarWindow.Topmost = true;

            ABSetPos(info.Edge, appbarWindow);                
        }

        private delegate void ResizeDelegate(Window appbarWindow, Rect rect);
        private static void DoResize(Window appbarWindow, Rect rect)
        {
            appbarWindow.Width = rect.Width;
            appbarWindow.Height = rect.Height;
            appbarWindow.Top = rect.Top;
            appbarWindow.Left = rect.Left;
        }



        private static void ABSetPos(ABEdge edge, Window appbarWindow)
        {
            APPBARDATA barData = new APPBARDATA();
            barData.cbSize = Marshal.SizeOf(barData);
            barData.hWnd = new WindowInteropHelper(appbarWindow).Handle;
            barData.uEdge = (int)edge;

            if (barData.uEdge == (int)ABEdge.Left || barData.uEdge == (int)ABEdge.Right)
            {
                barData.rc.top = 0;
                barData.rc.bottom = (int)SystemParameters.PrimaryScreenHeight;
                if (barData.uEdge == (int)ABEdge.Left)
                {
                    barData.rc.left = 0;
                    barData.rc.right = (int)Math.Round(appbarWindow.ActualWidth);
                }
                else
                {
                    barData.rc.right = (int)SystemParameters.PrimaryScreenWidth;
                    barData.rc.left = barData.rc.right - (int)Math.Round(appbarWindow.ActualWidth);
                }
            }
            else
            {
                barData.rc.left = 0;
                barData.rc.right = (int)SystemParameters.PrimaryScreenWidth;
                if (barData.uEdge == (int)ABEdge.Top)
                {
                    barData.rc.top = 0;
                    barData.rc.bottom = (int)Math.Round(appbarWindow.ActualHeight);
                }
                else
                {
                    barData.rc.bottom = (int)SystemParameters.PrimaryScreenHeight;
                    barData.rc.top = barData.rc.bottom - (int)Math.Round(appbarWindow.ActualHeight);
                }
            }

            SHAppBarMessage((int)ABMsg.ABM_QUERYPOS, ref barData);
            SHAppBarMessage((int)ABMsg.ABM_SETPOS, ref barData);

            Rect rect = new Rect((double)barData.rc.left, (double)barData.rc.top, 
                (double)(barData.rc.right - barData.rc.left), (double)(barData.rc.bottom - barData.rc.top));
            //This is done async, because WPF will send a resize after a new appbar is added.  
            //if we size right away, WPFs resize comes last and overrides us.
            appbarWindow.Dispatcher.BeginInvoke(DispatcherPriority.ApplicationIdle, 
                new ResizeDelegate(DoResize), appbarWindow, rect);
        }
    }
}