Added REAL code for the initial parent of a control on Windows.

init_windows.c

@@ -6,8 +6,6 @@ int nCmdShow;
 
 HFONT hMessageFont;
 
-HWND initialParent;
-
 struct uiInitError {
 	char *msg;
 	char failbuf[256];
@@ -95,10 +93,9 @@ const char *uiInit(uiInitOptions *o)
 	if (hMessageFont == NULL)
 		return loadLastError("loading default messagebox font; this is the default UI font");
 
-	// give each control a reasonable initial parent
-	// don't free the initial parent!
-	// TODO tune this better; it shouldn't be closed, for instance
-	initialParent = (HWND) uiWindowHandle(uiNewWindow("", 0, 0));
+	ce = initInitialParent(hDefaultIcon, hDefaultCursor);
+	if (ce != NULL)
+		return loadLastError(ce);
 
 	return NULL;
 }

initparent_windows.c

@@ -0,0 +1,46 @@
+// 10 april 2015
+#include "uipriv_windows.h"
+
+// for maximum safety, all controls that don't have a parent are made children of this, the "initial parent"
+// it behaves like other containers due to bugs described in container_windows.c, but is never seen and cannot be interacted with by end users
+// despite being called the initial parent, it is used whenever a control has no parent, even if it loses its parent at some later point during the execution of the program
+
+#define uiInitialParentClass L"uiInitialParentClass"
+
+HWND initialParent;
+
+static LRESULT CALLBACK initialParentWndProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
+{
+	LRESULT lResult;
+
+	if (sharedWndProc(hwnd, uMsg, wParam, lParam, &lResult) != FALSE)
+		return lResult;
+	return DefWindowProcW(hwnd, uMsg, wParam, lParam);
+}
+
+const char *initInitialParent(HICON hDefaultIcon, HCURSOR hDefaultCursor)
+{
+	WNDCLASSW wc;
+
+	ZeroMemory(&wc, sizeof (WNDCLASSW));
+	wc.lpszClassName = uiInitialParentClass;
+	wc.lpfnWndProc = initialParentWndProc;
+	wc.hInstance = hInstance;
+	wc.hIcon = hDefaultIcon;
+	wc.hCursor = hDefaultCursor;
+	wc.hbrBackground = (HBRUSH) (COLOR_BTNFACE + 1);
+	if (RegisterClassW(&wc) == 0)
+		return "registering initial parent window class";
+
+	initialParent = CreateWindowExW(0,
+		uiInitialParentClass, L"",
+		WS_OVERLAPPEDWINDOW,
+		0, 0,
+		100, 100,
+		NULL, NULL, hInstance, NULL);
+	if (initialParent == NULL)
+		return "creating initial parent window";
+
+	// TODO disable?
+	return NULL;
+}

uipriv_windows.h

@@ -64,3 +64,6 @@ extern const char *initCommonControls(void);
 
 // window_windows.c
 extern ATOM registerWindowClass(HICON, HCURSOR);
+
+// initparent_windows.c
+extern const char *initInitialParent(HICON, HCURSOR);