c++ - 无法更改 WinAPI 中的编辑控制文本

Question

这段代码一直有效，我不知道哪里出了问题，见下文:

CreateWindowW(L"EDIT", L"Type Here!", WS_CHILD | WS_VISIBLE | WS_BORDER, 10, 10, 150, 25, hwnd, (HMENU)ID_TEXTBOX1, NULL, NULL);

程序运行时创建控件时，可以选择文本并使用SetWindowText函数更改，但不能通过键入更改文本，为什么？

我看过堆栈溢出这个话题:win32 api edit control can't be selected or edited ，但即使使用 SetFocus 函数或 EnableWindow，它仍然不起作用。

这是整个程序的功能:

#include <windows.h>

// IDs dos controles
#define ID_TEXTBOX1 1000
#define ID_BUTTON1 1001

LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);

int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
  LPSTR pCmdLine, int nCmdShow)
{
 MSG msg;
 HWND hwnd;
 WNDCLASSW wc;

 wc.style     = CS_HREDRAW | CS_VREDRAW;
 wc.cbClsExtra  = 0;
 wc.cbWndExtra  = 0;
 wc.lpszClassName = L"WINDOW";
 wc.hInstance   = hInstance;
 wc.hbrBackground = GetSysColorBrush(COLOR_3DFACE);
 wc.lpszMenuName = NULL;
 wc.lpfnWndProc  = WndProc;
 wc.hCursor    = LoadCursor(NULL, IDC_ARROW);
 wc.hIcon     = LoadIcon(NULL, IDI_APPLICATION);

 RegisterClassW(&wc);
 hwnd = CreateWindowW(L"WINDOW", L"Janela",
        WS_OVERLAPPEDWINDOW | WS_VISIBLE,
        100, 100, 200, 200, NULL, NULL, hInstance, NULL);

 ShowWindow(hwnd, nCmdShow);
 UpdateWindow(hwnd);

 while( GetMessage(&msg, NULL, 0, 0)) {
  DispatchMessage(&msg);
}

 return (int) msg.wParam;
}

LRESULT CALLBACK WndProc(HWND hwnd, UINT msg,
  WPARAM wParam, LPARAM lParam)
{
 switch(msg)
 {
  case WM_CREATE:
      // Here is creted the edit control
      CreateWindowW(L"EDIT", L"Type Here!", WS_CHILD | WS_VISIBLE | WS_BORDER, 10, 10, 150, 25,       hwnd, (HMENU)ID_TEXTBOX1, NULL, NULL);
   // Functions that i tried
   //EnableWindow(GetDlgItem(hwnd, ID_TEXTBOX1), true);
   //SetFocus(GetDlgItem(hwnd, ID_TEXTBOX1));
   // Here is create a button
      CreateWindowW(L"BUTTON", L"Show Text", WS_CHILD | WS_VISIBLE, 10, 45, 100, 20, hwnd, (HMENU)ID_BUTTON1, NULL, NULL);
   break;
 case WM_COMMAND:
   switch (LOWORD(wParam))
   {
   case ID_BUTTON1:
       int len = GetWindowTextLengthW(GetDlgItem(hwnd, ID_TEXTBOX1)) + 1;
       wchar_t *txt = new wchar_t[len];
       GetWindowText(GetDlgItem(hwnd, ID_TEXTBOX1), txt, len);
       //
       MessageBox(NULL, txt, L"Info", MB_OK);
       delete txt;
       break;
   }
   break;
 case WM_DESTROY:
   PostQuitMessage(0);
   return 0;
 }

 return DefWindowProcW(hwnd, msg, wParam, lParam);
}

Answer 1

您错过了对 TranslateMessage 的调用在你的消息循环中，防止键盘输入生成 WM_CHAR/WM_UNICHAR消息。这将使您的 Edit 控件看起来没有任何输入。参见 GetMessage用于标准消息循环实现。

顺便说一句，在分配数组时，需要使用数组删除运算符，即delete[] txt;。