Windows程序设计——窗口键盘消息滚动事件[通俗易懂]

大家好，又见面了，我是你们的朋友全栈君。

文章目录

• 头文件
• 源文件

头文件

#pragma once
#include <Windows.h>

#define NUMLINES ((int)(sizeof sysmetrics/sizeof sysmetrics[0]))

struct { 
   
	int Index;
	char szLabel[100];	//第一列内容
	char szDesc[50];	//第二列内容
}sysmetrics[] = { 
   
SM_CXSCREEN,"各位同学大家好","官方标准提示数据",
SM_CYSCREEN,"C/C++高级工程师","官方标准发布版本"
};           

复制

NUMLINES 宏定义是为了得到sysmetrics的数量

源文件

#include <Windows.h>
#include "systems.h"

LRESULT CALLBACK WndProcFun(HWND, UINT, WPARAM, LPARAM);

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow)
{ 
   
	static TCHAR szAppName[] = TEXT("CKDemoTest");
	HWND hwnd;
	MSG msg;
	WNDCLASS windclass;

	windclass.style = CS_HREDRAW | CS_VREDRAW;
	windclass.lpfnWndProc = WndProcFun;
	windclass.cbClsExtra = 0;
	windclass.cbWndExtra = 0;
	windclass.hInstance = hInstance;
	windclass.hIcon = NULL;
	windclass.hCursor = LoadCursor(NULL, IDC_ARROW);
	windclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
	windclass.lpszMenuName = NULL;
	windclass.lpszClassName = szAppName;

	if (!RegisterClass(&windclass))
	{ 
   
		// 提示信息自己完成 
		return 0;
	}

	hwnd = CreateWindow(szAppName, TEXT("第五讲 键盘控制窗口垂直水平滚事件"), WS_OVERLAPPEDWINDOW | WS_VSCROLL | WS_HSCROLL,CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hInstance, NULL);

	ShowWindow(hwnd, iCmdShow);
	UpdateWindow(hwnd);

	while (GetMessage(&msg, NULL, 0, 0)) { 
   
		TranslateMessage(&msg);
		DispatchMessage(&msg);
	}

	return msg.wParam;

}


LRESULT CALLBACK WndProcFun(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{ 
   
	static int cxChar, cxCaps, cyChar, cxClient, cyClient, iMaxWidth;
	HDC hdc;
	int i, x, y, iVertPos, iHorzPos=0, iPaintBeg, iPaintEnd;
	PAINTSTRUCT ps;
	SCROLLINFO si;
	TCHAR szBuffer[20];
	TEXTMETRIC tm;

	switch (message)
	{ 
   
	case WM_CREATE:  // 应用程序创建一个窗口
		hdc = GetDC(hwnd);
		GetTextMetrics(hdc, &tm);
		cxChar = tm.tmAveCharWidth;
		cyChar = tm.tmHeight + tm.tmExternalLeading;
		cxCaps = (tm.tmPitchAndFamily & 1 ? 3 : 2)*cxChar / 2;
		ReleaseDC(hwnd, hdc);

		// 保存三列宽度
		iMaxWidth = 40 * cxChar + 22 * cxCaps;
		return 0;

	case WM_SIZE:	// 改变一个窗口的大小
		cxClient = LOWORD(lParam);
		cyClient = HIWORD(lParam);

		// 设置垂直滚动条范围 和 页面大小
		si.cbSize = sizeof(si);

		// SIF_RANGE 设置滚动范围值
		// SIF_PAGE 设置滚动页码
		si.fMask = SIF_RANGE | SIF_PAGE;
		si.nMin = 0;
		si.nMax = NUMLINES - 1;
		si.nPage = cyClient / cyChar;
		// SB_VERT 设置所给定的窗体上标准垂直滚动条参数
		SetScrollInfo(hwnd, SB_VERT, &si, TRUE);
		return 0;

	case WM_PAINT:
		hdc = BeginPaint(hwnd, &ps);

		// 获取垂直滚动条位置
		si.cbSize = sizeof(si);
		si.fMask = SIF_POS;
		GetScrollInfo(hwnd, SB_VERT, &si);
		iVertPos = si.nPos;

		// 查找绘制限制
		iPaintBeg = max(0, iVertPos + ps.rcPaint.top / cyChar);
		iPaintEnd = min(NUMLINES - 1, iVertPos + ps.rcPaint.bottom / cyChar);

		for (i = iPaintBeg; i <= iPaintEnd; i++)
		{ 
   
			x = cxChar * (1 - iHorzPos);
			y = cyChar * (i - iVertPos);

			TextOut(hdc, x, y, sysmetrics[i].szLabel, lstrlen(sysmetrics[i].szLabel));
			TextOut(hdc, x+80*cxCaps, y, sysmetrics[i].szDesc, lstrlen(sysmetrics[i].szDesc));
			SetTextAlign(hdc, TA_RIGHT | TA_TOP);		// 指定设备环境设置文字对齐标志

			TextOut(hdc, x + 100 * cxCaps + 40 * cxChar, y, szBuffer, wsprintf(szBuffer, TEXT("%d"), GetSystemMetrics(sysmetrics[i].Index)));
			SetTextAlign(hdc, TA_LEFT | TA_TOP);
		}

		EndPaint(hwnd, &ps);
		return 0;

	case WM_KEYDOWN:
		switch (wParam)
		{ 
   
		case VK_HOME:   // Home
			SendMessage(hwnd, WM_VSCROLL, SB_TOP, 0);	// 消息发送到一个或多个窗口
			break;

		case VK_END:	// End
			SendMessage(hwnd, WM_VSCROLL, SB_BOTTOM, 0);
			break;

		case VK_PRIOR:	// Page Up
			SendMessage(hwnd, WM_VSCROLL, SB_PAGEUP, 0);
			break;

		case VK_NEXT:	// Page Down
			SendMessage(hwnd, WM_VSCROLL, SB_PAGEDOWN, 0);
			break;

		case VK_UP:	// 箭头向上
			SendMessage(hwnd, WM_VSCROLL, SB_LINEUP, 0);
			break;

		case VK_DOWN:	// 箭头向下
			SendMessage(hwnd, WM_VSCROLL, SB_LINEDOWN, 0);
			break;
		}
		return 0;

	case WM_VSCROLL:
		// 获取所有垂直滚动条信息
		si.cbSize = sizeof(si);
		si.fMask = SIF_ALL;	// 整个结构都有效
		GetScrollInfo(hwnd, SB_VERT, &si);		// SB_VERT 设置所绽的窗口上标准垂直滚动条参数

		iVertPos = si.nPos;

		switch (LOWORD(wParam))
		{ 
   
		case SB_TOP:
			si.nPos = si.nMin;
			break;

		case SB_BOTTOM:
			si.nPos = si.nMax;
			break;

		case SB_LINEUP:
			si.nPos -= 1;
			break;

		case SB_LINEDOWN:
			si.nPos +=1;
			break;

		case SB_PAGEUP:
			si.nPos -= si.nPage;
			break;

		case SB_PAGEDOWN:
			si.nPos += si.nPage;
			break;

		case SB_THUMBTRACK:
			si.nPos = si.nTrackPos;
			break;

		default:
			break;

		}
		si.fMask = SIF_POS;
		SetScrollInfo(hwnd, SB_VERT, &si, TRUE);
		GetScrollInfo(hwnd, SB_VERT, &si);

		// 如果位置已经更改，滚动窗口并且进行更新
		if (si.nPos != iVertPos)
		{ 
   
			ScrollWindow(hwnd, 0, cyChar*(iVertPos - si.nPos), NULL, NULL);
			UpdateWindow(hwnd);
		}

		return 0;

	case WM_DESTROY:
		PostQuitMessage(0);
		return 0;
	}

	return DefWindowProc(hwnd, message, wParam, lParam);
}           

复制

运行结果只能垂直滚动，水平滚动参考即可，

不懂得可以留言，希望可以帮助到各位朋友。

发布者：全栈程序员栈长，转载请注明出处：https://javaforall.cn/171006.html原文链接：https://javaforall.cn