Oops forgot to commit this before midnight: started work on uiWindow children.

common/uipriv.h

@@ -86,6 +86,8 @@ extern uint32_t uiprivSysWindowType(void);
 extern uiWindow *uiprivSysNewWindow(void);
 extern const char *uiprivSysWindowTitle(uiWindow *w);
 extern void uiprivSysWindowSetTitle(uiWindow *w, const char *title);
+extern uiControl *uiprivSysWindowChild(uiWindow *w);
+extern void uiprivSysWindowSetChild(uiWindow *w, uiControl *child);
 
 #ifdef __cplusplus
 }

common/window.c

@@ -40,3 +40,25 @@ void uiWindowSetTitle(uiWindow *w, const char *title)
 	}
 	uiprivSysWindowSetTitle(w, title);
 }
+
+uiControl *uiWindowChild(uiWindow *w)
+{
+	if (!uiprivCheckInitializedAndThread())
+		return NULL;
+	if (w == NULL) {
+		uiprivProgrammerErrorNullPointer("uiWindow", uiprivFunc);
+		return NULL;
+	}
+	return uiprivSysWindowChild(w);
+}
+
+void uiWindowSetChild(uiWindow *w, uiControl *child)
+{
+	if (!uiprivCheckInitializedAndThread())
+		return;
+	if (w == NULL) {
+		uiprivProgrammerErrorNullPointer("uiWindow", uiprivFunc);
+		return;
+	}
+	uiprivSysWindowSetChild(w, child);
+}

darwin/window.m

@@ -6,8 +6,8 @@
 struct windowImplData {
 	NSWindow *window;
 	char *title;
-#if 0
 	uiControl *child;
+#if 0
 	int margined;
 	int (*onClosing)(uiWindow *, void *);
 	void *onClosingData;
@@ -377,7 +377,7 @@ static bool windowInit(uiControl *c, void *implData, void *initData)
 	[wi->window setTitle:@""];
 
 	// do NOT release when closed
-	// we manually do this in uiWindowDestroy() above
+	// we manually do this in Free() below
 	[wi->window setReleasedWhenClosed:NO];
 
 #if 0
@@ -393,10 +393,25 @@ static bool windowInit(uiControl *c, void *implData, void *initData)
 	return true;
 }
 
+static void connectChild(struct windowImplData *wi)
+{
+	// TODO
+}
+
+static void disconnectChild(struct winodwImplData *wi)
+{
+	// TODO
+}
+
 static void windowFree(uiControl *c, void *implData)
 {
 	struct windowImplData *wi = (struct windowImplData *) implData;
 
+	if (wi->child != NULL) {
+		disconnectChild(wi);
+		uiControlFree(wi->child);
+		wi->child = NULL;
+	}
 	if (wi->title != NULL) {
 		uiprivFreeUTF8(wi->title);
 		wi->title = NULL;
@@ -469,6 +484,24 @@ void uiprivSysWindowSetTitle(uiWindow *w, const char *title)
 	[wi->window setTitle:[NSString stringWithUTF8String:wi->title]];
 }
 
+uiControl *uiprivSysWindowChild(uiWindow *w)
+{
+	struct windowImplData *wi = (struct windowImplData *) uiControlImplData(uiControl(w));
+
+	return wi->child;
+}
+
+void uiprivSysWindowSetChild(uiWindow *w, uiControl *child)
+{
+	struct windowImplData *wi = (struct windowImplData *) uiControlImplData(uiControl(w));
+
+	if (wi->child != NULL)
+		disconnectChild(wi);
+	wi->child = child;
+	if (wi->child != NULL)
+		connectChild(wi);
+}
+
 #if 0
 
 // utility function for menus

doc/window.md

@@ -57,3 +57,25 @@ void uiWindowSetTitle(uiWindow *w, const char *title);
 It is a programmer error to pass `NULL` for `title`. If `title` is not valid UTF-8, `U+FFFD` characters will be used to sanitize the string.
 
 It is a programmer error to pass `NULL` for `w`.
+
+### `uiWindowChild()`
+
+```c
+uiprivExtern uiControl *uiWindowChild(uiWindow *w);
+```
+
+`uiWindowChild()` returns the current child of `w`, or `NULL` if there is none.
+
+It is a programmer error to pass `NULL` for `w`.
+
+### `uiWindowSetChild()`
+
+```c
+uiprivExtern void uiWindowSetChild(uiWindow *w, uiControl *child);
+```
+
+`uiWindowSetChild()` sets the child control of `w` to `child`. If `child` is `NULL`, `w` will have its child removed, and the window will be empty. If `w` already has a child, then the child is seamlessly swapped out, and the current child will be free to add to another parent.
+
+A window can only have one child control at a time, and that child will be given the entire area of the window. Multiple controls within a window are handled using the other container control types.
+
+It is a programmer error to pass `NULL` for `w`. It is also a programmer error to pass a control for `child` that is already the child of some other control.

ui.h

@@ -74,6 +74,8 @@ uiprivExtern uint32_t uiWindowType(void);
 uiprivExtern uiWindow *uiNewWindow(void);
 uiprivExtern const char *uiWindowTitle(uiWindow *w);
 uiprivExtern void uiWindowSetTitle(uiWindow *w, const char *title);
+uiprivExtern uiControl *uiWindowChild(uiWindow *w);
+uiprivExtern void uiWindowSetChild(uiWindow *w, uiControl *child);
 
 #ifdef __cplusplus
 }