当我改变他的背景时，我失去了按钮的功能

Question

我尝试了所有源代码通过实现子类化来替换按钮的背景。

当我改变背景时，我得到了一个正方形的形状，无法点击它。有人可以分享一个好的教程或代码示例吗？

无论如何，这是我的代码：

LRESULT CALLBACK DrawPushButton(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
HDC          hdcMem;
HBITMAP      hbmMem;
HANDLE       hnd;
PAINTSTRUCT  ps;
HDC          hdc;
int win_width=100;
int win_height=50;
    switch(uMsg)
    {
    case WM_PAINT:
        hdc = BeginPaint(hwnd, &ps);
        hdcMem = CreateCompatibleDC(hdc);
        hbmMem = CreateCompatibleBitmap(hdc, win_width, win_height);
        hnd   = SelectObject(hdcMem, hbmMem);
        BitBlt(hdc, 0, 0, win_width, win_height, hdcMem, 0, 0, SRCCOPY);
        EndPaint(hwnd, &ps);
        return 0;
        break;
    }
    return CallWindowProc (OldWndProc, hwnd, uMsg, wParam, lParam);
}

编辑：我为按钮添加了BS_OWNERDRAW窗口样式：

HWND hWndButton=CreateWindowEx(NULL,L"BUTTON",L"OK",WS_TABSTOP|WS_VISIBLE|WS_CHILD|BS_DEFPUSHBUTTON|BS_OWNERDRAW,50,220,100,24,hWnd,(HMENU)IDC_MAIN_BUTTON,GetModuleHandle(NULL),NULL);

我更改了回调，但WM_DRAWTITEM没有调用：

LRESULT CALLBACK DrawPushButton(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    switch(uMsg)
    {
    case WM_DRAWITEM:
            HDC hdc = GetDC(hwnd);
            TextOut(hdc,0,0,L"itay",4);
        break;
    }
    return 0;
}

Answer 1

这不是一个"好"代码，尽管它是功能性的——正如前面提到的，你可能应该使用BS_OWNERDRAW样式，并在包含按钮的对话框/窗口的wndpoc中处理图形。我选择粘贴一个旧的例子，用和你一样的方式来处理它。你必须自己完成这幅画的所有。然而，您确实有机会响应按钮收到的WM_TIMER消息，该消息会使按钮跳动。（如果只从对话框/窗口的WindowProc绘制，则不确定是否有机会这样做）

为了简单起见，我还选择使用一种被取代的子类方法。由于通用控件的版本6，您应该使用SetWindowSubclass(http://msdn.microsoft.com/en-us/library/windows/desktop/bb762102（v=vs.85）.aspx）

main.cpp

#include <windows.h>
#include <commctrl.h>
#include <stdio.h>
#include "resource.h"
HINSTANCE hInst;
LRESULT CALLBACK btnProc(HWND btnWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    long oldWndProc;
    int i;
    oldWndProc = GetWindowLong(btnWnd, GWL_USERDATA);
    switch (uMsg)
    {
        case WM_PAINT:
            {
                HDC hdc;
                PAINTSTRUCT ps;
                RECT mRect;
                HBRUSH mBrush;
                hdc = BeginPaint(btnWnd, &ps);
                mBrush = CreateSolidBrush( RGB(100, 147, 111));
                GetClientRect(btnWnd, &mRect);
                FillRect(hdc, &mRect, mBrush);
                DeleteObject(mBrush);
                EndPaint(btnWnd, &ps);
            }
            return 0;
    }
    return CallWindowProc((WNDPROC)oldWndProc, btnWnd, uMsg, wParam, lParam);
}

void onCommand(HWND hwndDlg, WPARAM wParam, LPARAM lParam)
{
    switch (LOWORD(wParam))
    {
    case IDC_BUTTON1:
        MessageBeep(MB_ICONEXCLAMATION);
        break;
    }
}
LRESULT CALLBACK DlgMain(HWND hwndDlg, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
    switch(uMsg)
    {
        case WM_INITDIALOG:
        {
            HWND btnWnd;
            long oldBtnProc;
            btnWnd = GetDlgItem(hwndDlg, IDC_BUTTON1);
            oldBtnProc = GetWindowLong(btnWnd, GWL_WNDPROC);
            SetWindowLong(btnWnd, GWL_USERDATA, oldBtnProc);
            SetWindowLong(btnWnd, GWL_WNDPROC, (long)btnProc);
        }
        return TRUE;
        case WM_CLOSE:
        {
            EndDialog(hwndDlg, 0);
        }
        return TRUE;
        case WM_COMMAND:
            onCommand(hwndDlg, wParam, lParam);
            return TRUE;
    }
    return FALSE;
}

int APIENTRY WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nShowCmd)
{
    hInst=hInstance;
    InitCommonControls();
    return DialogBox(hInst, MAKEINTRESOURCE(DLG_MAIN), NULL, (DLGPROC)DlgMain);
}

资源.h

#ifndef IDC_STATIC
#define IDC_STATIC (-1)
#endif
#define DLG_MAIN                                100
#define IDC_BUTTON1                             1000

资源.rc

// Generated by ResEdit 1.5.11
// Copyright (C) 2006-2012
// http://www.resedit.net
#include <windows.h>
#include <commctrl.h>
#include <richedit.h>
#include "resource.h"
//
// Dialog resources
//
LANGUAGE LANG_NEUTRAL, SUBLANG_NEUTRAL
DLG_MAIN DIALOG 0, 0, 186, 95
STYLE DS_3DLOOK | DS_CENTER | DS_MODALFRAME | DS_SHELLFONT | WS_CAPTION | WS_VISIBLE | WS_POPUP | WS_SYSMENU
CAPTION "Dialog"
FONT 8, "Ms Shell Dlg"
{
    PUSHBUTTON      "Button1", IDC_BUTTON1, 7, 7, 50, 14
}
//
// Manifest resources
//
LANGUAGE LANG_NEUTRAL, SUBLANG_NEUTRAL
1                  RT_MANIFEST    ".\manifest.xml"

manifest.xml

<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<assembly xmlns="urn:schemas-microsoft-com:asm.v1" manifestVersion="1.0">
  <dependency>
    <dependentAssembly>
      <assemblyIdentity type="win32" name="Microsoft.Windows.Common-Controls" version="6.0.0.0" processorArchitecture="*" publicKeyToken="6595b64144ccf1df" language="*"/>
    </dependentAssembly>
  </dependency>
  <trustInfo xmlns="urn:schemas-microsoft-com:asm.v3">
    <security>
      <requestedPrivileges>
        <requestedExecutionLevel
          level="asInvoker"
          uiAccess="false"/>
      </requestedPrivileges>
    </security>
  </trustInfo>
</assembly>