我目前是Win 32 API的初学者，正在制作一个示例程序。我遇到的问题是我找不到一种适当的方法来设置窗口的最小大小，以便在窗口达到最小值时能看到其中的文本（居中）。除了达到某个“临界”大小后，文本只部分可见或根本看不到外，在所有其他情况下文本都是完全可见的。
我找到了如何更改窗口的宽度和高度，如下所示：
我找到了如何更改窗口的宽度和高度，如下所示：
LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
switch (message)
{
case WM_DESTROY:
PostQuitMessage (0);
break;
case WM_GETMINMAXINFO:
((MINMAXINFO*)lParam)->ptMinTrackSize.x =100; //apply custom min width
((MINMAXINFO*)lParam)->ptMinTrackSize.y =100; //apply custom min height
break;
case WM_PAINT:
{
PAINTSTRUCT ps;
HDC hdc = BeginPaint (hwnd, &ps);
GetClientRect(hwnd,&rc);
DrawText (hdc, TEXT ("Sample text here"), -1, &rc,DT_SINGLELINE | DT_CENTER | DT_VCENTER ) ;
EndPaint (hwnd, &ps);
}
break;
default:
return DefWindowProc (hwnd, message, wParam, lParam);
}
return 0;
}
我认为这些行需要改变，但我不知道需要做哪些改变。
((MINMAXINFO*)lParam)->ptMinTrackSize.x =100; //apply custom min width
((MINMAXINFO*)lParam)->ptMinTrackSize.y =100; //apply custom min height
我的想法是，不要将明确的浮点值赋给 POINT 结构的 x 和 y 成员，而应该调用一个函数来确定文本的最小宽度和高度。
任何帮助都将不胜感激。
以下是此程序的完整代码。
#if defined(UNICODE) && !defined(_UNICODE)
#define _UNICODE
#elif defined(_UNICODE) && !defined(UNICODE)
#define UNICODE
#endif
#include <tchar.h>
#include <windows.h>
#include <stdio.h>
/* Declare Windows procedure */
LRESULT CALLBACK WindowProcedure (HWND, UINT, WPARAM, LPARAM);
/* Make the class name into a global variable */
TCHAR szClassName[ ] = _T("CodeBlocksWindowsApp");
RECT rc;
int WINAPI WinMain (HINSTANCE hThisInstance,
HINSTANCE hPrevInstance,
LPSTR lpszArgument,
int nCmdShow)
{
HWND hwnd; /* This is the handle for our window */
MSG messages; /* Here messages to the application are saved */
WNDCLASSEX wincl; /* Data structure for the windowclass */
wincl.hInstance = hThisInstance;
wincl.lpszClassName = szClassName;
wincl.lpfnWndProc = WindowProcedure; /* This function is called by windows */
wincl.style = CS_DBLCLKS | CS_VREDRAW | CS_HREDRAW; /* Catch double-clicks */
wincl.cbSize = sizeof (WNDCLASSEX);
wincl.hIcon = LoadIcon (NULL, IDI_APPLICATION);
wincl.hIconSm = LoadIcon (NULL, IDI_APPLICATION);
wincl.hCursor = LoadCursor (NULL, IDC_ARROW);
wincl.lpszMenuName = NULL; /* No menu */
wincl.cbClsExtra = 0; /* No extra bytes after the window class */
wincl.cbWndExtra = 0; /* structure or the window instance */
wincl.hbrBackground = (HBRUSH) COLOR_BACKGROUND;
if (!RegisterClassEx (&wincl))
return 0;
hwnd = CreateWindowEx (
0, /* Extended possibilites for variation */
szClassName, /* Classname */
_T("Code::Blocks Template Windows App"),
/* Title Text */
WS_OVERLAPPEDWINDOW, /* default window */
CW_USEDEFAULT, /* Windows decides the position */
CW_USEDEFAULT, /* where the window ends up on the screen */
544, /* The programs width */
375, /* and height in pixels */
HWND_DESKTOP, /* The window is a child-window to desktop */
NULL, /* No menu */
hThisInstance, /* Program Instance handler */
NULL /* No Window Creation data */
);
ShowWindow (hwnd, nCmdShow);
while (GetMessage (&messages, NULL, 0, 0))
{
TranslateMessage(&messages);
DispatchMessage(&messages);
}
return messages.wParam;
}
LRESULT CALLBACK WindowProcedure (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
switch (message)
{
case WM_DESTROY:
PostQuitMessage (0);
break;
case WM_GETMINMAXINFO:
//window size/position is going to change
//apply custom min width/height 350,50
SIZE sz;
HDC hdc = GetDC( hwnd );
TCHAR* myString = TEXT("Sample Text!");
HFONT oldFont, myFont; //create your own font
//select your font into device context
oldFont = (HFONT)SelectObject( hdc, myFont );
//get font dimensions
GetTextExtentPoint32( hdc, myString, _tcslen( myString ), &sz );
((MINMAXINFO*)lParam)->ptMinTrackSize.x = sz.cx;
((MINMAXINFO*)lParam)->ptMinTrackSize.y = sz.cy;
//cleanup
SelectObject( hdc, oldFont );
DeleteObject( myFont );
ReleaseDC( hwnd, hdc );
break;
case WM_PAINT:
{
PAINTSTRUCT ps;
HDC hdc = BeginPaint (hwnd, &ps);
GetClientRect(hwnd,&rc);
DrawText (hdc, TEXT("Sample Text!"), -1, &rc, DT_SINGLELINE | DT_CENTER | DT_VCENTER | DT_WORDBREAK ) ;
EndPaint (hwnd, &ps);
}
break;
default:
return DefWindowProc (hwnd, message, wParam, lParam);
}
return 0;
}
对于糟糕的缩进表示歉意。