on_paint.rar_onpaint函数_visual c

#include <Windows.h> #include "on_paint.h" #include<wingdi.h> #include<WindowsX.h> struct decode_unit main_message_proc[]={ WM_DESTROY,on_destory, WM_PAINT,on_paint, }; LRESULT CALLBACK WndProc(HWND hwnd,UINT message,WPARAM wParam,LPARAM lParam); int WinMain(HINSTANCE hInstance, HINSTANCE prehInstance, LPTSTR lpCmdLine, int nShow) { //1.创建一个窗体类 WNDCLASS ws; ws.cbClsExtra =0; ws.cbWndExtra =0; ws.hbrBackground =(HBRUSH) GetStockObject(WHITE_BRUSH); ws.hCursor =NULL; ws.hIcon =NULL; ws.hInstance =hInstance; ws.lpfnWndProc =WndProc; ws.lpszClassName =TEXT("Hello"); ws.lpszMenuName =NULL; ws.style =CS_VREDRAW |CS_HREDRAW; //2.注册窗体类 if(!RegisterClass(&ws)) return -1; //3.创建窗体类 HWND hwnd=CreateWindow(TEXT("Hello"),TEXT("My First Windows"),WS_VISIBLE | WS_BORDER| WS_SYSMENU | WS_MINIMIZEBOX |WS_MAXIMIZEBOX |WS_CAPTION, 10,10,400,300,NULL,NULL,hInstance,NULL ); //4.更新窗体内容 UpdateWindow(hwnd); ShowWindow(hwnd,nShow); MSG msg; //5.获取系统消息 while(GetMessage(&msg,NULL,0,0)) { TranslateMessage(&msg); DispatchMessage(&msg); } return 1; } LRESULT CALLBACK WndProc(HWND hwnd,UINT message,WPARAM wParam,LPARAM lParam) { for(int i=0;i<dim(main_message_proc);i++) { if(main_message_proc[i].message == message) (*main_message_proc[i].fun)(hwnd,message,wParam,lParam); } return DefWindowProc(hwnd,message,wParam,lParam); /*switch(message) { case WM_DESTROY: on_destory(hwnd,message,wParam,lParam); break; case WM_PAINT: on_paint(hwnd,message,wParam,lParam); break; default: DefWindowProc(hwnd,message,wParam,lParam); } return 0;*/ } LONG on_destory(HWND hwnd,UINT message,WPARAM wParam,LPARAM lParam) { PostQuitMessage(1); return TRUE; } LONG on_paint(HWND hwnd,UINT message,WPARAM wParam,LPARAM lParam) { PAINTSTRUCT ps; HDC hdc; RECT rect; HPEN hpen; GetClientRect(hwnd,&rect); hdc=BeginPaint(hwnd,&ps); hpen = CreatePen(PS_SOLID,2,RGB(0XFF,0X00,0X00)); //hpen=GetStockPen(BLACK_PEN);//是对getstockobject函数的封装 HGDIOBJ oldpen=SelectObject(hdc,hpen);//放到设备环境中 Ellipse(hdc,10,10,200,200);//一个黑色画笔的圆 SelectObject(hdc,oldpen); DeleteObject(hpen); DrawText(hdc,TEXT("HELLO WORLD"),-1,&rect,DT_VCENTER |DT_CENTER); EndPaint(hwnd,&ps); return 0; }