update

src/main.c

@@ -1,3 +1,4 @@
+#include <shobjidl.h>
 #include <stdio.h>
 #include <wchar.h>
 #include <windows.h>
@@ -9,25 +10,113 @@
 
 // #ifdef __MINGW32__
 
+typedef struct {
+    const char* msg;
+    int num;
+} State;
+
+void OnSize(HWND hwnd, UINT flag, int width, int height) {
+    printf("Window resize: flag: %d, width: %d, height: %d\n", flag, width, height);
+}
+
 LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam) {
+    State* pState = NULL;
+    if (uMsg == WM_CREATE) {
+        CREATESTRUCT* pCreate = (CREATESTRUCT*) lParam;
+        pState = (State*) pCreate->lpCreateParams;
+        SetWindowLongPtr(hwnd, GWLP_USERDATA, (LONG_PTR) pState);
+    } else {
+        LONG_PTR ptr = GetWindowLongPtr(hwnd, GWLP_USERDATA);
+        pState = (State*) ptr;
+    }
+
     switch (uMsg) {
+    case WM_LBUTTONDOWN:
+        printf("State: msg: %s, num: %d\n", pState->msg, pState->num);
+        return 0;
+
     case WM_DESTROY:
         PostQuitMessage(0);
         return 0;
 
-    case WM_PAINT: {
+    case WM_CLOSE:
+        if (MessageBox(hwnd, L"Really quit?", L"My Application", MB_OKCANCEL) == IDOK) {
+            DestroyWindow(hwnd);
+        }
+        return 0;
+
+    case WM_SIZE:
+    {
+        int width = LOWORD(lParam);
+        int height = HIWORD(lParam);
+        OnSize(hwnd, (UINT) wParam, width, height);
+        return 0;
+    }
+
+    case WM_PAINT:
+    {
         PAINTSTRUCT ps;
         HDC hdc = BeginPaint(hwnd, &ps);
 
         FillRect(hdc, &ps.rcPaint, (HBRUSH) (COLOR_WINDOW + 1));
+        RECT blue = {
+            .bottom = 100,
+            .left = 0,
+            .right = 100,
+            .top = 0
+        };
+        FillRect(hdc, &blue, (HBRUSH) (COLOR_BACKGROUND + 1));
 
         EndPaint(hwnd, &ps);
-    }
         return 0;
     }
+    }
     return DefWindowProc(hwnd, uMsg, wParam, lParam);
 }
 
+void show_open_dialog(HWND hwnd) {
+    HRESULT hr = CoInitializeEx(NULL, COINIT_APARTMENTTHREADED | COINIT_DISABLE_OLE1DDE);
+    if (FAILED(hr)) {
+        printf("COM init failed\n");
+        exit(1);
+    }
+
+#define OPEN_DIALOG_CHECK_ERR(msg) \
+    if (FAILED((hr))) { \
+        printf("%s:%d: %s", __FILE__, __LINE__, (msg)); \
+        exit(1); \
+    }
+
+    IFileOpenDialog* pFileOpen;
+    hr = CoCreateInstance(
+        &CLSID_FileOpenDialog,
+        NULL,
+        CLSCTX_ALL,
+        &IID_IFileOpenDialog,
+        (void**) &pFileOpen
+    );
+    OPEN_DIALOG_CHECK_ERR("ERROR: Failed to create FileOpenDialog\n");
+
+    hr = pFileOpen->lpVtbl->Show(pFileOpen, hwnd);
+    OPEN_DIALOG_CHECK_ERR("ERROR: Failed to show FileOpenDialog\n");
+
+    IShellItem* pItem;
+    hr = pFileOpen->lpVtbl->GetResult(pFileOpen, &pItem);
+    OPEN_DIALOG_CHECK_ERR("ERROR: Failed to get open file dialog result.\n")
+
+    PWSTR pszFilePath;
+    hr = pItem->lpVtbl->GetDisplayName(pItem, SIGDN_FILESYSPATH, &pszFilePath);
+    OPEN_DIALOG_CHECK_ERR("ERROR: Failed to get path\n");
+
+    MessageBox(NULL, pszFilePath, L"File Path", MB_OK);
+
+    CoTaskMemFree(pszFilePath);
+    pItem->lpVtbl->Release(pItem);
+    pFileOpen->lpVtbl->Release(pFileOpen);
+
+    CoUninitialize();
+}
+
 int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR pCmdLine, int nCmdShow) {
     // Register the window class
     const wchar_t* CLASS_NAME = L"Sample Window Class";
@@ -39,20 +128,25 @@ int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR pCmdLine,
 
     RegisterClass(&wc);
 
+    State s = {
+        .msg = "This is state",
+        .num = 69420
+    };
+
     // Create the window
     HWND hwnd = CreateWindowEx(
-        0, // Optional window styles
-        CLASS_NAME, // Window class
+        0,                           // Optional window styles
+        CLASS_NAME,                  // Window class
         L"Learn to Program Windows", // Window text
-        WS_OVERLAPPEDWINDOW, // Window style
+        WS_OVERLAPPEDWINDOW,         // Window style
 
         // Size and position
         CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT,
 
-        NULL, // Parent window
-        NULL, // Menu
+        NULL,      // Parent window
+        NULL,      // Menu
         hInstance, // Instance handle
-        NULL // Additional application data
+        &s         // Additional application data
     );
 
     if (hwnd == NULL) {
@@ -62,9 +156,11 @@ int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance, LPSTR pCmdLine,
 
     ShowWindow(hwnd, nCmdShow);
 
+    show_open_dialog(hwnd);
+
     // Message loop
 
-    MSG msg = {};
+    MSG msg = { };
     while (GetMessage(&msg, NULL, 0, 0) > 0) {
         TranslateMessage(&msg);
         DispatchMessage(&msg);