#include<windows.h>#include<tchar.h>#include<iostream>#include"resource.h" //很重要，要引入资源头文件/*
首先你的理解，window绘图基本原理，WM_PAINT 有效区，无效区。 非无效区域不绘制，即便你写了绘制代码。Window会判断的，但是要求效率的时候你可以参看tagPAINTSTRUCT rect. 通过InValidRect ValidRect 可以使得窗口有效或者无效。
WM_PAINT 消息优先级别比较低，如果要立即显示，请调用UpdateWindow()，此消息不进入队列。关于进队不进队列消息，参考进队消息那一篇文章
什么时候产生WM_PAINT 这里需要说明下InvalidateRect(hWnd,&reClient,TRUE); 函数理解 最后一个参数，TRUE当前无效区域将被背景删除。FALSE不被删除。 背景是我们在设定WNDCLASS时候hBackGround */void MessageBoxPrintf(char* pszCaputre,char* Format,...) { va_list vaList;//equal to Format + sizeof(FOrmat) char szBuff[100]; memset(szBuff,0,sizeof(char)*100); va_start(vaList,Format); //vsPrintf 三个参数 buff,format,参数数组的指针，va_list类型的。这个函数 // 多用于实现多个参数的自定义函数 _vsnprintf(szBuff,100,Format,vaList); va_end(vaList); MessageBoxA(NULL,szBuff,pszCaputre,MB_OK); } LRESULT CALLBACK WinProc(HWND hWnd,UINT uMsg,WPARAM wParam,LPARAM lParam)//LRESULT long型的指针。 CALLBACK _stacall{ HDC hDc =NULL; CHAR aszScrollPosMsg[100]; static int iVerScrollPos = 0; static RECT reClient; struct tagPAINTSTRUCT ps; switch(uMsg) { case WM_CREATE: SetScrollRange(hWnd,SB_VERT,0,10,FALSE); SetScrollPos(hWnd,SB_VERT,0,FALSE); break; case WM_PAINT: hDc = BeginPaint(hWnd,&ps); GetClientRect(hWnd,&reClient); wsprintfA(aszScrollPosMsg,"VerScrollPos is %d ",iVerScrollPos); TextOutA(hDc,200+iVerScrollPos*30,200+iVerScrollPos*30,aszScrollPosMsg,strlen(aszScrollPosMsg)); //DrawTextA(hDc,aszScrollPosMsg,-1,&reClient,SND_FILENAME|SND_ASYNC); EndPaint(hWnd,&ps); break; case WM_CLOSE: //消息处理在WM_DESTORY 前面 if(IDOK == MessageBoxA(NULL,"Close","Warning",MB_OKCANCEL))//我们在编程过程中喜欢在if判断时候把常量放在左边，可以避免错误 { DestroyWindow(hWnd); //发出WM_DESTORY 消息 } break; case WM_DESTROY: PostQuitMessage(0);//使得GetMessage返回0 break; case WM_VSCROLL: iVerScrollPos = GetScrollPos(hWnd,SB_VERT); switch(LOWORD(wParam)) { case SB_LINEUP: //鼠标点击滚动条上面的按钮 iVerScrollPos -= 1; break; case SB_LINEDOWN: iVerScrollPos += 1; break; case SB_THUMBTRACK: iVerScrollPos = HIWORD(wParam); break; case SB_THUMBPOSITION: iVerScrollPos = HIWORD(wParam); break; default: break; } RECT re; //无效区域设置为0,0,0,0 也不会引起TextOut的绘制，加载在BeginPaint和EndPaint中间的绘图代码，windows会自动判断 //是否需要更新绘制，若果在有效区外面不会绘制。 re.bottom = 0; re.top =0; re.left =0; re.right =0; SetScrollPos(hWnd,SB_VERT,iVerScrollPos,TRUE); InvalidateRect(hWnd,&reClient,FALSE); //发送WM_PAINT消息,此处不会发送WM_Paint消息，Scroll调用ScrollWindow滚动客户区函数才会发生消息 break; default: return DefWindowProc(hWnd,uMsg,wParam,lParam); } return 0;}INT WINAPI WinMain(HINSTANCE hInstance,HINSTANCE hPreInstance,LPSTR lpszCmd,int nCmdShow)//win32 的时候hPreInstance总为NULL，不检查，16位时候检查运行可以共用窗口类{ WNDCLASS wndClass; HCURSOR hCursor = LoadCursor(hInstance,MAKEINTRESOURCE(IDC_CURSOR1));//load 参数第一个NULL表示在系统内部找，适合第一默认的，系统共有，自己定义就设为自己句柄 HICON hIocn = LoadIcon(hInstance,MAKEINTRESOURCE(IDI_ICON1));// IDC_CURSOR1 是ID表示转化字符串表示，int 转化为字符串 wndClass.cbClsExtra = 0; wndClass.cbWndExtra = 0; wndClass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH); wndClass.hCursor = hCursor; wndClass.hIcon =hIocn; wndClass.hInstance = hInstance; //注意一定要赋值为当前进程的hInstance wndClass.lpfnWndProc = WinProc; wndClass.lpszClassName=_T("MyWindow"); wndClass.lpszMenuName = MAKEINTRESOURCE(IDR_MENU1); wndClass.style =CS_HREDRAW|CS_VREDRAW; if(RegisterClass(&wndClass)==NULL) MessageBoxPrintf("warning","%s","Register"); HMENU hMenue = LoadMenu(hInstance,MAKEINTRESOURCE(IDR_MENU1)); HWND hWnd = CreateWindowA("MyWindow","mytest",WS_VSCROLL|WS_OVERLAPPEDWINDOW,CW_USEDEFAULT,CW_USEDEFAULT,500,500,NULL,NULL,hInstance,NULL); if(hWnd==NULL) MessageBoxPrintf("warning","%s","create error"); ShowWindow(hWnd,nCmdShow); UpdateWindow(hWnd); MSG msg; //NULL // GetMessage retrieves messages for any window that belongs to the calling thread and thread messages posted to the calling thread using the PostThreadMessage function. while(GetMessage(&msg,NULL,NULL,NULL))//注意GetMessage(&msg,hWnd,NULL,NULL)是不可以的,NULL表示接受自己创建的所有窗口 { TranslateMessage(&msg); DispatchMessage(&msg); } return 0;}
