Windows程序设计学习笔记二——输出文字及滚动列

时间:2021-12-28 16:26:12

/*----------------------------------------------------sysmets.h
----------------------------------------------------*/
/*-----------------------------------------------
SYSMETS.H -- System metrics display structure
-----------------------------------------------*/

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

struct
{
int iIndex ;
TCHAR * szLabel ;
TCHAR * szDesc ;
}
sysmetrics [] =
{
SM_CXSCREEN, TEXT ("SM_CXSCREEN"),
TEXT ("Screen width in pixels"),
SM_CYSCREEN, TEXT ("SM_CYSCREEN"),
TEXT ("Screen height in pixels"),
SM_CXVSCROLL, TEXT ("SM_CXVSCROLL"),
TEXT ("Vertical scroll width"),
SM_CYHSCROLL, TEXT ("SM_CYHSCROLL"),
TEXT ("Horizontal scroll height"),
SM_CYCAPTION, TEXT ("SM_CYCAPTION"),
TEXT ("Caption bar height"),
SM_CXBORDER, TEXT ("SM_CXBORDER"),
TEXT ("Window border width"),
SM_CYBORDER, TEXT ("SM_CYBORDER"),
TEXT ("Window border height"),
SM_CXFIXEDFRAME, TEXT ("SM_CXFIXEDFRAME"),
TEXT ("Dialog window frame width"),
SM_CYFIXEDFRAME, TEXT ("SM_CYFIXEDFRAME"),
TEXT ("Dialog window frame height"),
SM_CYVTHUMB, TEXT ("SM_CYVTHUMB"),
TEXT ("Vertical scroll thumb height"),
SM_CXHTHUMB, TEXT ("SM_CXHTHUMB"),
TEXT ("Horizontal scroll thumb width"),
SM_CXICON, TEXT ("SM_CXICON"),
TEXT ("Icon width"),
SM_CYICON, TEXT ("SM_CYICON"),
TEXT ("Icon height"),
SM_CXCURSOR, TEXT ("SM_CXCURSOR"),
TEXT ("Cursor width"),
SM_CYCURSOR, TEXT ("SM_CYCURSOR"),
TEXT ("Cursor height"),
SM_CYMENU, TEXT ("SM_CYMENU"),
TEXT ("Menu bar height"),
SM_CXFULLSCREEN, TEXT ("SM_CXFULLSCREEN"),
TEXT ("Full screen client area width"),
SM_CYFULLSCREEN, TEXT ("SM_CYFULLSCREEN"),
TEXT ("Full screen client area height"),
SM_CYKANJIWINDOW, TEXT ("SM_CYKANJIWINDOW"),
TEXT ("Kanji window height"),
SM_MOUSEPRESENT, TEXT ("SM_MOUSEPRESENT"),
TEXT ("Mouse present flag"),
SM_CYVSCROLL, TEXT ("SM_CYVSCROLL"),
TEXT ("Vertical scroll arrow height"),
SM_CXHSCROLL, TEXT ("SM_CXHSCROLL"),
TEXT ("Horizontal scroll arrow width"),
SM_DEBUG, TEXT ("SM_DEBUG"),
TEXT ("Debug version flag"),
SM_SWAPBUTTON, TEXT ("SM_SWAPBUTTON"),
TEXT ("Mouse buttons swapped flag"),
SM_CXMIN, TEXT ("SM_CXMIN"),
TEXT ("Minimum window width"),
SM_CYMIN, TEXT ("SM_CYMIN"),
TEXT ("Minimum window height"),
SM_CXSIZE, TEXT ("SM_CXSIZE"),
TEXT ("Min/Max/Close button width"),
SM_CYSIZE, TEXT ("SM_CYSIZE"),
TEXT ("Min/Max/Close button height"),
SM_CXSIZEFRAME, TEXT ("SM_CXSIZEFRAME"),
TEXT ("Window sizing frame width"),
SM_CYSIZEFRAME, TEXT ("SM_CYSIZEFRAME"),
TEXT ("Window sizing frame height"),
SM_CXMINTRACK, TEXT ("SM_CXMINTRACK"),
TEXT ("Minimum window tracking width"),
SM_CYMINTRACK, TEXT ("SM_CYMINTRACK"),
TEXT ("Minimum window tracking height"),
SM_CXDOUBLECLK, TEXT ("SM_CXDOUBLECLK"),
TEXT ("Double click x tolerance"),
SM_CYDOUBLECLK, TEXT ("SM_CYDOUBLECLK"),
TEXT ("Double click y tolerance"),
SM_CXICONSPACING, TEXT ("SM_CXICONSPACING"),
TEXT ("Horizontal icon spacing"),
SM_CYICONSPACING, TEXT ("SM_CYICONSPACING"),
TEXT ("Vertical icon spacing"),
SM_MENUDROPALIGNMENT, TEXT ("SM_MENUDROPALIGNMENT"),
TEXT ("Left or right menu drop"),
SM_PENWINDOWS, TEXT ("SM_PENWINDOWS"),
TEXT ("Pen extensions installed"),
SM_DBCSENABLED, TEXT ("SM_DBCSENABLED"),
TEXT ("Double-Byte Char Set enabled"),
SM_CMOUSEBUTTONS, TEXT ("SM_CMOUSEBUTTONS"),
TEXT ("Number of mouse buttons"),
SM_SECURE, TEXT ("SM_SECURE"),
TEXT ("Security present flag"),
SM_CXEDGE, TEXT ("SM_CXEDGE"),
TEXT ("3-D border width"),
SM_CYEDGE, TEXT ("SM_CYEDGE"),
TEXT ("3-D border height"),
SM_CXMINSPACING, TEXT ("SM_CXMINSPACING"),
TEXT ("Minimized window spacing width"),
SM_CYMINSPACING, TEXT ("SM_CYMINSPACING"),
TEXT ("Minimized window spacing height"),
SM_CXSMICON, TEXT ("SM_CXSMICON"),
TEXT ("Small icon width"),
SM_CYSMICON, TEXT ("SM_CYSMICON"),
TEXT ("Small icon height"),
SM_CYSMCAPTION, TEXT ("SM_CYSMCAPTION"),
TEXT ("Small caption height"),
SM_CXSMSIZE, TEXT ("SM_CXSMSIZE"),
TEXT ("Small caption button width"),
SM_CYSMSIZE, TEXT ("SM_CYSMSIZE"),
TEXT ("Small caption button height"),
SM_CXMENUSIZE, TEXT ("SM_CXMENUSIZE"),
TEXT ("Menu bar button width"),
SM_CYMENUSIZE, TEXT ("SM_CYMENUSIZE"),
TEXT ("Menu bar button height"),
SM_ARRANGE, TEXT ("SM_ARRANGE"),
TEXT ("How minimized windows arranged"),
SM_CXMINIMIZED, TEXT ("SM_CXMINIMIZED"),
TEXT ("Minimized window width"),
SM_CYMINIMIZED, TEXT ("SM_CYMINIMIZED"),
TEXT ("Minimized window height"),
SM_CXMAXTRACK, TEXT ("SM_CXMAXTRACK"),
TEXT ("Maximum dragable width"),
SM_CYMAXTRACK, TEXT ("SM_CYMAXTRACK"),
TEXT ("Maximum dragable height"),
SM_CXMAXIMIZED, TEXT ("SM_CXMAXIMIZED"),
TEXT ("Width of maximized window"),
SM_CYMAXIMIZED, TEXT ("SM_CYMAXIMIZED"),
TEXT ("Height of maximized window"),
SM_NETWORK, TEXT ("SM_NETWORK"),
TEXT ("Network present flag"),
SM_CLEANBOOT, TEXT ("SM_CLEANBOOT"),
TEXT ("How system was booted"),
SM_CXDRAG, TEXT ("SM_CXDRAG"),
TEXT ("Avoid drag x tolerance"),
SM_CYDRAG, TEXT ("SM_CYDRAG"),
TEXT ("Avoid drag y tolerance"),
SM_SHOWSOUNDS, TEXT ("SM_SHOWSOUNDS"),
TEXT ("Present sounds visually"),
SM_CXMENUCHECK, TEXT ("SM_CXMENUCHECK"),
TEXT ("Menu check-mark width"),
SM_CYMENUCHECK, TEXT ("SM_CYMENUCHECK"),
TEXT ("Menu check-mark height"),
SM_SLOWMACHINE, TEXT ("SM_SLOWMACHINE"),
TEXT ("Slow processor flag"),
SM_MIDEASTENABLED, TEXT ("SM_MIDEASTENABLED"),
TEXT ("Hebrew and Arabic enabled flag"),
SM_MOUSEWHEELPRESENT, TEXT ("SM_MOUSEWHEELPRESENT"),
TEXT ("Mouse wheel present flag"),
SM_XVIRTUALSCREEN, TEXT ("SM_XVIRTUALSCREEN"),
TEXT ("Virtual screen x origin"),
SM_YVIRTUALSCREEN, TEXT ("SM_YVIRTUALSCREEN"),
TEXT ("Virtual screen y origin"),
SM_CXVIRTUALSCREEN, TEXT ("SM_CXVIRTUALSCREEN"),
TEXT ("Virtual screen width"),
SM_CYVIRTUALSCREEN, TEXT ("SM_CYVIRTUALSCREEN"),
TEXT ("Virtual screen height"),
SM_CMONITORS, TEXT ("SM_CMONITORS"),
TEXT ("Number of monitors"),
SM_SAMEDISPLAYFORMAT, TEXT ("SM_SAMEDISPLAYFORMAT"),
TEXT ("Same color format flag")
} ;

/*-------------------------------------------------*/


/*----------------------------------------------------Scroll.cpp
----------------------------------------------------*/
#include <windows.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 ("SysMets3") ;
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 ("Program requires Windows NT!"),
szAppName, MB_ICONERROR) ;
return 0 ;
}

hwnd = CreateWindow (szAppName, TEXT ("Get System Metrics No. 3"),
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 WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
static int cxChar, cxCaps, cyChar, cxClient, cyClient, iMaxWidth ;
HDC hdc ;
int i, x, y, iVertPos, iHorzPos, iPaintBeg, iPaintEnd ;
PAINTSTRUCT ps ;
SCROLLINFO si ;
TCHAR szBuffer[10] ;
TEXTMETRIC tm ;

switch (message)
{
case WM_CREATE:
hdc = GetDC (hwnd) ;

GetTextMetrics (hdc, &tm) ;
cxChar = tm.tmAveCharWidth ;//平均字符宽度
cxCaps = (tm.tmPitchAndFamily & 1 ? 3 : 2) * cxChar / 2 ;//字符高度
cyChar = tm.tmHeight + tm.tmExternalLeading ;

ReleaseDC (hwnd, hdc) ;

// Save the width of the three columns

iMaxWidth = 40 * cxChar + 22 * cxCaps ;
return 0 ;

case WM_SIZE:
cxClient = LOWORD (lParam) ;//客户区的宽
cyClient = HIWORD (lParam) ;//客户区的高

// Set vertical scroll bar range and page size

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) ;

// Set horizontal scroll bar range and page size

si.cbSize = sizeof (si) ;
si.fMask = SIF_RANGE | SIF_PAGE ;
si.nMin = 0 ;
si.nMax = 2 + iMaxWidth / cxChar ;
si.nPage = cxClient / cxChar ;
SetScrollInfo (hwnd, SB_HORZ, &si, TRUE) ;
return 0 ;

case WM_VSCROLL:
// Get all the vertial scroll bar information

si.cbSize = sizeof (si) ;
si.fMask = SIF_ALL ;
GetScrollInfo (hwnd, SB_VERT, &si) ;

// Save the position for comparison later on

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 ;
}
// Set the position and then retrieve it. Due to adjustments
// by Windows it may not be the same as the value set.

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

// If the position has changed, scroll the window and update it

if (si.nPos != iVertPos)
{
ScrollWindow (hwnd, 0, cyChar * (iVertPos - si.nPos),
NULL, NULL) ;
UpdateWindow (hwnd) ;
}
return 0 ;

case WM_HSCROLL:
// Get all the vertial scroll bar information

si.cbSize = sizeof (si) ;
si.fMask = SIF_ALL ;

// Save the position for comparison later on

GetScrollInfo (hwnd, SB_HORZ, &si) ;
iHorzPos = si.nPos ;

switch (LOWORD (wParam))
{
case SB_LINELEFT:
si.nPos -= 1 ;
break ;

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

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

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

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

default :
break ;
}
// Set the position and then retrieve it. Due to adjustments
// by Windows it may not be the same as the value set.

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

// If the position has changed, scroll the window

if (si.nPos != iHorzPos)
{
ScrollWindow (hwnd, cxChar * (iHorzPos - si.nPos), 0,
NULL, NULL) ;
}
return 0 ;

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

// Get vertical scroll bar position

si.cbSize = sizeof (si) ;
si.fMask = SIF_POS ;
GetScrollInfo (hwnd, SB_VERT, &si) ;
iVertPos = si.nPos ;

// Get horizontal scroll bar position

GetScrollInfo (hwnd, SB_HORZ, &si) ;
iHorzPos = si.nPos ;

// Find painting limits

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 + 22 * cxCaps, y,
sysmetrics[i].szDesc,
lstrlen (sysmetrics[i].szDesc)) ;

SetTextAlign (hdc, TA_RIGHT | TA_TOP) ;

TextOut (hdc, x + 22 * cxCaps + 40 * cxChar, y, szBuffer,
wsprintf (szBuffer, TEXT ("%5d"),
GetSystemMetrics (sysmetrics[i].iIndex))) ;

SetTextAlign (hdc, TA_LEFT | TA_TOP) ;
}

EndPaint (hwnd, &ps) ;
return 0 ;

case WM_DESTROY :
PostQuitMessage (0) ;
return 0 ;
}
return DefWindowProc (hwnd, message, wParam, lParam) ;
}

关于这一部分的内容我并没有完全的弄懂,为了继续学习新的知识,我决定暂且先放一放不懂的地方,等到以后用得上的时候,再来总结学习,这应该会比纠结在这个知识点上的学习效率会高。接下来我将谈谈我自己对这一块内容的学习掌握,比较的low,但是是自己的学习输出。

一、首先理解几个结构体

在学习笔记一中接触到了HWND、MSG、WNDCLASS、HDC、PAINTSTRUCT、RECT这几个结构体,这一节内容在此基础上新增了TEXTMETRICSCROLLINFO两个结构体,其中TEXTMETRIC在WINGDI.H中定义的型态的结构,用于储存和字体有关的属性,具体的成员可以自行搜索,本节需要用到的是用来确定字体的宽度和高度的成员。SCROLLINFO,是和滚动条(滚动列)属性有关的结构体,具体成员可以自行搜索,这次需要用到的是用来确定滚动列位置相关的变量。

二、输出文字

在第一个Windows窗口的基础上,不需要改变窗口函数的内容,只需要在消息处理函数中对应消息响应操作修改即可。

1、WM_CREATE消息处理:要获得需要的字体相关属性,供WM_PAINT消息处理时使用

(1)获取装置内容hdc=GetDC(hwnd);

(2)获得系统字体的相关属性GetTextMetrics(参数表略);

(3)保存相关字体属性用tm.tmAveCharWidth、tm.tmHeight等TEXTMETRIC结构中的成员来给声明的变量赋值

(4)释放装置内容ReleaseDC(hwnd,hdc);

2、WM_PAINT消息处理:画出所需要的客户区域,并填充内容

(1)获取装置内容:hdc=BeginPaint(hwnd,&ps);

(2)设置对齐格式:SetTextAlign(参数表略);

(3)设置输出文字:TextOut(参数表略);

(4)释放装置内容:EndPaint(hwnd,&ps);

三、在输出文字基础上添加滚动列

重点是SetScrollInfo()和GetScrollInfo()两个函数

1、修改CreateWindow()中第三个参数,更改为带有滚动列的视图样式

WS_VSCROLL  |  WS_HSCROLL

2、处理消息函数的改动,WM_CREATE消息处理,通输出文字的处理方式相同

3、新引入的消息WM_SIZE:当主窗口的大小改变时,接收到这个消息

(1)处理SCROLLINFO结构,给结构体内的相关成员变量赋值,重点成员是cbsize和fMask,以及相关的变量成员

(2)赋完值后,设置滚动列的属性SetScrollInfo(hwnd, SB_VERT, &si, TRUE);参数表为示例

4、新引入的消息WM_VSCROLL  |  WM_HSCROLL:当窗口的滚动条中有滚动事件发生时,窗口应用程序的消息队列产生这个消息

(1)处理SCROLLINFO结构,只需要给cbSize和fMask两个变量赋值即可,fMask设置为  [SIF_...],以确定哪些成员可以被访问

(2)获取滚动列的相关属性GetScrollInfo(hwnd, SB_VERT, &si);

(3)处理wParam参数的低字组的通知讯息 [SB_...],switch分支语句

(4)处理SCROLLINFO结构,只需要给cbSize和fMask两个变量赋值即可,fMask设置为  [SIF_...]

(5)设置滚动列属性后再获取 SetScrollInfo(hwnd, SB_VERT, &si, TRUE);

GetScrollInfo(hwnd, SB_VERT, &si);

(6)判断滚动列位置是否改变,若改变,则滚动窗口ScrollWindowhwnd, 0, cyChar * (iVertPos - si.nPos),  NULL, NULL);//示例参数表

并更新UpdateWindows(hwnd);

5、WM_PAINT消息的修改

利用更细节的方法确定每一次输出文字的位置,使得滚动列的滚动效果更好,详见代码

对于本部分内容,我自己不是特别的清晰,如果有明白的看官,希望可以分享一下学习心得,多谢啦。



以下附上《Windows程序设计(第5版)》提供源码的子集再现版(基本是一模一样),知识自己在相对独立的情况下手敲了一遍。