滚动条
为什么下面代码不行呀：/* -------------------------------------------------------------------
MyWindows.c -- 基本窗口模型
《Windows 程序设计（SDK）》视频教程
--------------------------------------------------------------------*/
#include <windows.h>
#include "strsafe.h"
#include "sysmets.h"
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow)
{
static TCHAR szAppName[] = TEXT("MyWindows");
HWND hwnd;
MSG msg;
WNDCLASS wndclass;
wndclass.style = CS_HREDRAW | CS_VREDRAW;
wndclass.lpfnWndProc = WndProc;
wndclass.cbClsExtra = 0;
wndclass.cbWndExtra = 0;
wndclass.hInstance = hInstance;
wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH);
wndclass.lpszMenuName = NULL;
wndclass.lpszClassName = szAppName;
if (!RegisterClass(&wndclass))
{
MessageBox(NULL, TEXT("这个程序需要在 Windows NT 才能执行！"), szAppName, MB_ICONERROR);
return 0;
}
hwnd = CreateWindow(szAppName,
TEXT("鱼C工作室"),
WS_OVERLAPPEDWINDOW | WS_VSCROLL,
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 WndProc(HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
HDC hdc;
PAINTSTRUCT ps;
TEXTMETRIC tm;
TCHAR szBuffer;
static int cxChar, cxCaps, cyChar, cxClient, cyClient, iVscrollPos;
size_t iTarget;
int i, y, FirstLine, LastLine;
SCROLLINFO si;
switch (message)
{
case WM_CREATE:
hdc = GetDC(hwnd);
GetTextMetrics(hdc, &tm);
cxChar = tm.tmAveCharWidth;
cxCaps = (tm.tmPitchAndFamily & 1 ? 3 : 2) * cxChar / 2;
cyChar = tm.tmHeight + tm.tmExternalLeading;
ReleaseDC(hwnd, hdc);
return 0;
case WM_PAINT:
hdc = BeginPaint(hwnd, &ps);
// 获取滚动条的位置
si.cbSize = sizeof(si);
si.fMask = SIF_POS;
GetScrollInfo(hwnd, SB_VERT, &si);
iVscrollPos = si.nPos;
// 计算需要重绘的区域
FirstLine = max(0, iVscrollPos + ps.rcPaint.top / cyChar);
LastLine = min(NUMLINES - 1, iVscrollPos + ps.rcPaint.bottom / cyChar);
for (i = FirstLine; i < LastLine; i++)
{
y = cyChar * (i - iVscrollPos);
StringCchLength(sysmetrics.szLabel, 1024, &iTarget);
TextOut(hdc, 0, y, sysmetrics.szLabel, iTarget);
StringCchLength(sysmetrics.szDesc, 1024, &iTarget);
TextOut(hdc, 22 * cxCaps, y, sysmetrics.szDesc, iTarget);
SetTextAlign(hdc, TA_RIGHT | TA_TOP);
StringCchPrintf(szBuffer, 10, TEXT("%5d"), GetSystemMetrics(sysmetrics.iIndex));
StringCchLength(szBuffer, 10, &iTarget);
TextOut(hdc, 22 * cxCaps + 40 * cxChar, y, szBuffer, iTarget);
SetTextAlign(hdc, TA_LEFT | TA_TOP);
}
EndPaint(hwnd, &ps);
return 0;
case WM_SIZE:
// 获得客户区的尺寸
cyClient = HIWORD(lParam);
cxClient = LOWORD(lParam);
// 设置垂直滚动条范围和页面大小（设置页面大小将决定滑块的粗细）
si.cbSize = sizeof(si);
si.fMask = SIF_RANGE | SIF_PAGE;
si.nMin = 0;
si.nMax = NUMLINES - 1;
si.nPage = cyClient / cyChar;
SetScrollInfo(hwnd, SB_VERT, &si, TRUE);
case WM_VSCROLL:
// 获得垂直滚动条的所有信息
si.cbSize = sizeof(si);
si.fMask = SIF_ALL;
GetScrollInfo(hwnd, SB_VERT, &si);
// 保存当前滑块位置，迟些进行比较
iVscrollPos = si.nPos;
switch (LOWORD(wParam))
{
// 用户点击键盘 Home 按键
case SB_TOP:
si.nPos = si.nMin;
break;
// 用户点击键盘 End 按键
case SB_BOTTOM:
si.nPos = si.nMax;
break;
// 用户点击滚动条上边的三角形
case SB_LINEUP:
si.nPos -= 1;
break;
// 用户点击滚动条下边的三角形
case SB_LINEDOWN:
si.nPos += 1;
break;
// 用户点击滑块上边的滚动条轴
case SB_PAGEUP:
si.nPos -= si.nPage;
break;
// 用户点击滑块下边的滚动条轴
case SB_PAGEDOWN:
si.nPos += si.nPage;
break;
// 用户拖动滚动条
case SB_THUMBTRACK:
si.nPos = si.nTrackPos;
break;
}
// 设置滚动条滑块的新位置
si.fMask = SIF_POS;
SetScrollInfo(hwnd, SB_VERT, &si, TRUE);
// 获得滚动条滑块的位置，由于窗口调整，它可能不是同一个值
GetScrollInfo(hwnd, SB_VERT, &si);
// 与此前的保存的值进行比较，如果不同则滚动窗口
if (si.nPos != iVscrollPos)
{
ScrollWindow(hwnd, 0, cyChar * (iVscrollPos - si.nPos), NULL, NULL);
UpdateWindow(hwnd);
}
return 0;
case WM_DESTROY:
PostQuitMessage(0);
return 0;
}
return DefWindowProc(hwnd, message, wParam, lParam);
}
问题1、如下图：
为什么这些文字没有都画出来？？
问题2、我调整窗口的宽度，滚动条还是会往上一行，
这该怎么解决？
试了一下你的代码，貌似没有问题啊
qiuyouzhi 发表于 2020-2-4 16:50
试了一下你的代码，貌似没有问题啊
我觉得你得编译器有问题...... lixiangyv 发表于 2020-2-23 18:11
我觉得你得编译器有问题......
VS2013??? qiuyouzhi 发表于 2020-2-23 18:13
VS2013???
2019 将你的firstline括号内最后面-1
页:
[1]