我目前是win 32 API的初学者，正在制作示例程序。我遇到的问题是我无法找到一种正确的方法来设置窗口的最小尺寸，以便当窗口达到最小值时，它内部的文本（居中）可见。在所有其他情况下，文本完全可见，除非我达到某个“关键”大小，之后文本部分可见或根本看不到。
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;
}
我认为应该改变这些界限，但我不知道需要做出哪些改变。
((MINMAXINFO*)lParam)->ptMinTrackSize.x =100; //apply custom min width
((MINMAXINFO*)lParam)->ptMinTrackSize.y =100; //apply custom min height
我的想法是，改为分配给POINT结构的x和y成员的显式浮点值，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。
以下是该计划的完整代码。
#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;
}
我为糟糕的缩进道歉。
答案 0 :(得分：0)
我认为GetTextExtentPoint32是您想要的，因此您可以计算文本大小和长度。 Here是显示如何使用它的示例。
万一您的文字尺寸大于屏幕尺寸，您可以在DrawText电话中添加DT_WORDBREAK标记 - 请参阅文档。
您需要创建字体并在设备上下文中选择它，CreateFontIndirect可以帮助您 - 关注LOGFONT structure的成员，以便您可以创建所需的字体。 Here就是这样做的一个例子。
尝试这样的事情：
case WM_PAINT:
{
PAINTSTRUCT ps;
HDC hdc = BeginPaint (hwnd, &ps);
//create your own font
HFONT oldFont, myFont;
// create logical font for menu
LOGFONT lf = { sizeof(lf) };
_tcscpy_s( lf.lfFaceName, ARRAYSIZE(lf.lfFaceName), L"Microsoft Sans Serif" );
lf.lfHeight = -MulDiv( 12, GetDeviceCaps( hdc, LOGPIXELSY), 72);
lf.lfWeight = FW_HEAVY;
lf.lfItalic = FALSE;
lf.lfUnderline = FALSE;
myFont = CreateFontIndirect(&lf);
//select your font into device context
oldFont = (HFONT)SelectObject( hdc, myFont );
GetClientRect(hwnd,&rc);
DrawText (hdc, TEXT("Sample Text!"), -1, &rc,
DT_SINGLELINE | DT_CENTER | DT_VCENTER | DT_WORDBREAK ) ;
//cleanup
SelectObject( hdc, oldFont );
DeleteObject( myFont );
EndPaint (hwnd, &ps);
}
return 0L;
case WM_GETMINMAXINFO:
{
SIZE sz;
HDC hdc = GetDC( hwnd );
LPTSTR myString = TEXT( "Sample text here" );
//create your own font
HFONT oldFont, myFont;
// create logical font for menu
LOGFONT lf = { sizeof(lf) };
_tcscpy_s( lf.lfFaceName, ARRAYSIZE(lf.lfFaceName), L"Microsoft Sans Serif" );
lf.lfHeight = -MulDiv( 12, GetDeviceCaps( hdc, LOGPIXELSY), 72);
lf.lfWeight = FW_HEAVY;
lf.lfItalic = FALSE;
lf.lfUnderline = FALSE;
myFont = CreateFontIndirect(&lf);
//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;
如果您还有其他问题，请发表评论。
最好的问候。