參考資訊:
http://www.winprog.org/tutorial/
http://winapi.freetechsecrets.com/win32/
https://github.com/gammasoft71/Examples_Win32
http://masm32.com/board/index.php?topic=3584.0
https://learn.microsoft.com/en-us/windows/win32/winmsg/window-styles
當視窗的可視區域(如:300x300像素)小於顯示圖片大小(如:640x480像素)時,這時可以使用Windows視窗元件Scrollbar,用來做顯示位置調整的動作,Scrollbar元件有垂直和水平兩種方向並且提供視窗事件回報機制(WM_VSCROLL、WM_HSCROLL),因此,這裡的Scrollbar元件並不能夠自動幫忙做顯示位置調整的動作,取而代之的是,在收到WM_VSCROLL、WM_HSCROLL事件時,使用者必須自己決定哪些東西要顯示在視窗的可視區域上
main.c
#include <stdbool.h> #include <stdio.h> #include <string.h> #include <windows.h> HWND hWin = NULL; WNDPROC defWndProc = NULL; LRESULT CALLBACK WndProc(HWND hWnd, UINT uMsg, WPARAM wParam, LPARAM lParam) { switch (uMsg) { case WM_CLOSE: DestroyWindow(hWnd); return 0; case WM_DESTROY: PostQuitMessage(0); return 0; case WM_VSCROLL: switch (LOWORD(wParam)) { case SB_LINEUP: SetWindowText(hWnd, "LINE++"); break; case SB_LINEDOWN: SetWindowText(hWnd, "LINE--"); break; case SB_PAGEUP: SetWindowText(hWnd, "PAGE++"); break; case SB_PAGEDOWN: SetWindowText(hWnd, "PAGE--"); break; } break; } return CallWindowProc(defWndProc, hWnd, uMsg, wParam, lParam); } int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine, int nCmdShow) { hWin = CreateWindow(WC_DIALOG, "main", WS_OVERLAPPEDWINDOW | WS_VISIBLE | WS_VSCROLL, 0, 0, 300, 300, NULL, NULL, NULL, NULL); defWndProc = (WNDPROC)SetWindowLongPtr(hWin, GWLP_WNDPROC, (long int)WndProc); SetScrollRange(hWin, SB_VERT, 0, 100, FALSE); SetScrollPos(hWin, SB_VERT, 50, TRUE); MSG msg = {0}; while (GetMessage(&msg, NULL, 0, 0)) { DispatchMessage(&msg); } ExitProcess(0); return 0; }
Line 18~33:處理Scrollbar訊息並且顯示在視窗標題
Line 41:WS_VSCROLL是垂直的Scrollbar,WS_HSCROLL則是水平的Scrollbar
Line 44:設定Scrollbar最大的範圍
Line 45:設定Scrollbar目前的位置
編譯、執行
$ winegcc main.c -o main $ wine ./main.exe