将hFont (CreateFontA)传递给CreateWindowEx

Question

解决了！

我最初的问题是CreateFont函数是否可以与CreateWindow函数一起使用。我在文档中找到的所有东西都让我相信它只适用于text函数。

由于我无法执行我得到的建议，并且在我的问题上没有取得任何进展，我采取了新的方法。我创建了测试代码，以便可以在WM_CREATE:和WM_PAINT:中所做的更改之间轻松切换。现在，我更容易找到我在文档中找到的东西，搜索和我脑海中突然出现的东西。

下面是我的测试代码。添加和删除styleSelection的注释让我可以选择我正在处理的内容。

全局: HFONT hFont；

LRESULT CALLBACK WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
  HDC hdc;

  string styleSelection = "WM_CREATE";
 //styleSelection = "WM_PAINT";

  switch(uMsg) {
     case WM_CLOSE: {
      DeleteObject(hFont);
      DestroyWindow(hWnd);
      break;
    }
    case WM_COMMAND: {
      DeleteObject(hFont);
      PostQuitMessage(0);
      break;
    }
    case WM_CREATE: {
      HINSTANCE hIns = ((LPCREATESTRUCT)lParam)->hInstance;
      if((styleSelection == "WM_CREATE") && (hFont = CreateFontA(18, 0, 0, 0, FW_DONTCARE, 1, 0, 0, ANSI_CHARSET, OUT_DEFAULT_PRECIS, CLIP_DEFAULT_PRECIS, PROOF_QUALITY, DEFAULT_PITCH, TEXT("DONTCARE")))) {

        int textHStart = 20; int textLineSpace = 16;
        vector < int > textVStart = { 20,60,100,120,160 };
        vector < string > newStrings;
        newStrings = getDynamicData();                    // Get the strings for output

        for(int i = 0; i < newStrings.size(); i++) {
          CreateWindowEx(NULL, TEXT("Static"), newStrings[i].c_str(), WS_CHILD | WS_VISIBLE, textHStart, textVStart[i], newStrings[i].length() * 10, textLineSpace, hWnd, (HMENU)IDC_USER_LABEL, hIns, NULL);
        }
      }

      HWND hButton = CreateWindowA(_T("button"), _T("Exit"), WS_CHILD | WS_VISIBLE, 385, 250, 60, 25, hWnd, (HMENU)IDC_BUTTON, hIns, 0);
      return 0;
    } 
    case WM_DESTROY: {
      DeleteObject(hFont);
      PostQuitMessage(0);
      break;
    }
    case WM_CTLCOLORSTATIC: { 
      HDC hEdit = (HDC)wParam;
      SetTextColor(hEdit, RGB(0, 0, 0)); 
      //SetBkColor(hEdit, RGB(0xFF, 0x00, 0x00)); 
      SetBkMode(hEdit, TRANSPARENT);
      return (INT_PTR)GetStockObject(HOLLOW_BRUSH);
    }
    case WM_PAINT: {
      PAINTSTRUCT ps;
      hdc = BeginPaint(hWnd, &ps);


      if((styleSelection == "WM_PAINT") && (hFont = CreateFontA(18, 0, 0, 0, FW_DONTCARE, 1, 0, 0, ANSI_CHARSET, OUT_DEFAULT_PRECIS, CLIP_DEFAULT_PRECIS, PROOF_QUALITY, DEFAULT_PITCH, TEXT("DONTCARE")))) {
          HFONT hOldFont = (HFONT)SelectObject(hdc, hFont);
        
        HDC hEdit = (HDC)wParam;
        SetTextColor(hdc, RGB(0, 0, 0));
        //SetBkColor(hdc, RGB(0xFF, 0x00, 0x00));
        SetBkMode(hdc, TRANSPARENT);
        
        int index = 7;                       // Vertical spaces and number of lines for the array
        const char* cpaText[7] = { "Hello,","", "What I want to do", "is to format this text." };

        for(int iLoopCounter = 0; cpaText[iLoopCounter] != 0; iLoopCounter++, index += 20) {
          TextOutA(hdc, 5, index, cpaText[iLoopCounter], strlen(cpaText[iLoopCounter]));
        }
        SelectObject(hdc, hOldFont);
      }
      EndPaint(hWnd, &ps);
      break;
    }
    default: {
      return DefWindowProcA(hWnd, uMsg, wParam, lParam);
      break;
    }
  }
  return DefWindowProcA(hWnd, uMsg, wParam, lParam);
}

////---- this is  the data to be printed.
vector < string > getDynamicData() {
  vector < string > retvec;
  retvec.push_back("This is a test.");
  retvec.push_back("I am trying to change the text");
  return retvec;
}

我最终想出的解决方案是在答案部分。

Answer 1

我的工作解决方案：

我的一个问题是WM_PAINT中的TextOut没有使用动态文本。回顾早先使用Jonathan Potter在Add dynamic text to WM_CREATE in C++ using variables中的建议解决的问题，我最终意识到同样的方法也适用于TextOut。

在我让TextOut处理动态文本之后，下一个选项是将WM_CREATE保留为标准字体样式，或者将所有内容迁移到WM_PAINT。我决定迁移到WM_PAINT将是更干净的解决方案。以下是我最终得到的结论：

全局: HFONT hFont；

   LRESULT CALLBACK WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
    HDC hdc;

    string styleSelection = "standardFont";
    styleSelection = "specialFont";

    switch(uMsg) {
      case WM_CREATE: {
        if(-1 == DefWindowProc(hWnd, WM_CREATE, wParam, lParam))
          return -1;
        hFont = CreateFontA(18, 0, 0, 0, FW_DONTCARE, 1, 0, 0, ANSI_CHARSET, OUT_DEFAULT_PRECIS, CLIP_DEFAULT_PRECIS, PROOF_QUALITY, DEFAULT_PITCH, TEXT("DONTCARE"));
        SetWindowLongPtr(hWnd, GWLP_USERDATA, (LPARAM)hFont);
      }
      break;case WM_CLOSE: {
        DeleteObject(hFont);
        DestroyWindow(hWnd);
        break;
      }
      case WM_COMMAND: {
        DeleteObject(hFont);
        PostQuitMessage(0);
        break;
      }
      case WM_DESTROY: {
        //DestroyObject((HFONT)GetWindowLongPtr(hWnd, GWLP_USERDATA));
        DeleteObject((HFONT)GetWindowLongPtr(hWnd, GWLP_USERDATA));
        return DefWindowProc(hWnd, WM_DESTROY, wParam, lParam);
      }
      case WM_PAINT: {
        PAINTSTRUCT ps;
        hdc = BeginPaint(hWnd, &ps);
        HDC hEdit = (HDC)wParam;
          SetBkMode(hdc, TRANSPARENT); 


        if(styleSelection == "standardFont") {
          SetTextColor(hdc, RGB(0, 0, 0));   

          int textHStart = 20; int textLineSpace = 16;
          vector < int > textVStart = { 20,60,100,120,160 };
          vector < string > newStrings;
          newStrings = getDynamicData();                    // Get the strings for output

          for(int i = 0; i < newStrings.size(); i++) {
            TextOutA(hdc, textHStart, textVStart[i], newStrings[i].c_str(), newStrings[i].size());
          }
        }
        else {
          DefWindowProc(hWnd, WM_PAINT, wParam, lParam);
          hFont = (HFONT)GetWindowLongPtr(hWnd, GWLP_USERDATA);
          HFONT hOldFont = (HFONT)SelectObject(hdc, hFont);
          SetTextColor(hdc, RGB(0xFF, 0x00, 0x00)); 

          int textHStart = 20; int textLineSpace = 16;
          vector < int > textVStart = { 20,60,100,120,160 };
          vector < string > newStrings;
          newStrings = getDynamicData();                    // Get the strings for output

          for(int i = 0; i < newStrings.size(); i++) {
            TextOutA(hdc, textHStart, textVStart[i], newStrings[i].c_str(), newStrings[i].size());
          }
          SelectObject(hdc, hOldFont);
          DeleteObject(hFont);

        }


        EndPaint(hWnd, &ps);
        break;
      }
      default: {
        return DefWindowProcA(hWnd, uMsg, wParam, lParam);
        break;
      }

上面的代码还实现了一些SoronelHaetir推荐的内容。我将根据SoronelHaetir的其余建议进行更多的研究，我仍然需要解决可能的内存泄漏问题和其他一些平滑项目，但这适用于我想要做的事情。它所需要的就是阅读，耐心和足够的毅力，直到我弄明白为止。

Answer 2

您不应该在WM_PAINT处理程序期间调用CreateWindow。

相反，您需要做的是保存在WM_CREATE处理程序中创建的字体，然后在以后获取WM_PAINT时使用该字体。带有GWLP_USERDATA的GetWindowLongPtr/SetWindowLongPtr是执行这种数据保存所提供的规范方法。

例如：

LRESULT WINAPI MyWindowProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
  switch(uMsg)
  {
  case WM_CREATE:
  {
    if(-1 == DefWindowProc(hWnd, WM_CREATE, wParam, lParam))
    return -1;
    HFONT hFont = CreateFont(...);
   SetWindowLongPtr(hWnd, GWLP_USERDATA, (LPARAM)hFont);
  }
    break;

  case WM_DESTROY:
    DestroyObject((HFONT)GetWindowLongPtr(hWnd, GWLP_USERDATA));
    return DefWindowProc(hWnd, WM_DESTROY, wParam, lParam);

  case WM_PAINT:
  {
    DefWindowProc(hWnd, WM_PAINT, wParam, lParam);
    HFONT hFont = (HFONT)GetWindowLongPtr(hWnd, GWLP_USERDATA);
    ...
  }
    break;

  default:
    return DefWindowProc(hWnd, uMsg, wParam, lParam);
}

  return 0;
}

还可以在实际创建窗口的任何代码中创建HFONT，并将该HFONT作为lParam参数传递给CreateWindow，然后在处理WM_CREATE时按说明保存它(而不是在处理WM_CREATE时实际创建HFONT )。

Answer 3

对于文本框，它已经完成了

    HFONT newFont = CreateFont(22, 0, 0, 0,0 , FALSE, FALSE, FALSE, DEFAULT_CHARSET,
    OUT_TT_PRECIS, CLIP_DEFAULT_PRECIS, CLEARTYPE_NATURAL_QUALITY,
    DEFAULT_PITCH | FF_DECORATIVE, L"Lucida Console");
    ::PostMessage(hc,WM_SETFONT,(WPARAM)newFont,(LPARAM)0);

您应该在其他地方创建所有这些内容

并使用WS_EX_COMPOSITED

将此::PostMessage(hc,WM_SETFONT,(WPARAM)newFont,(LPARAM)0);添加到您已有的for循环的末尾。但不是使用hc ofc