Sync BWindow fShowLevel with the app_server.

Implementing the window_info.show_hide_level in terms of this solves the
problem of minimized windows also being considered hidden, when really they are
just hidden in the app_server.

window_info.show_hide_level is still defined backwards with a comment making
that clear.

Also removed sending fShowLevel in the minimize request since it is now
maintained in the app_server.

Fixes #4127.

src/kits/interface/Window.cpp

@@ -596,7 +596,6 @@ BWindow::Minimize(bool minimize)
 
 	fLink->StartMessage(AS_MINIMIZE_WINDOW);
 	fLink->Attach<bool>(minimize);
-	fLink->Attach<int32>(fShowLevel);
 	fLink->Flush();
 
 	Unlock();
@@ -2612,6 +2611,7 @@ BWindow::Show()
 
 		if (fShowLevel == 1) {
 			fLink->StartMessage(AS_SHOW_WINDOW);
+			fLink->Attach<int32>(fShowLevel);
 			fLink->Flush();
 		}
 
@@ -2645,6 +2645,7 @@ BWindow::Hide()
 
 	if (fShowLevel == 0) {
 		fLink->StartMessage(AS_HIDE_WINDOW);
+		fLink->Attach<int32>(fShowLevel);
 		fLink->Flush();
 	}
 

src/servers/app/ServerWindow.cpp

@@ -481,7 +481,9 @@ ServerWindow::GetInfo(window_info& info)
 	info.window_right = (int)floor(fWindow->Frame().right);
 	info.window_bottom = (int)floor(fWindow->Frame().bottom);
 
-	info.show_hide_level = fWindow->IsHidden() ? 1 : 0; // ???
+	// This is essentially opposite of the ShowLevel, meaning a window is
+	// hidden if it is 1 or more, and shown if it is 0 or less.
+	info.show_hide_level = fWindow->ShowLevel() <= 0 ? 1 : 0;
 	info.is_mini = fWindow->IsMinimized();
 }
 
@@ -595,32 +597,40 @@ ServerWindow::_DispatchMessage(int32 code, BPrivate::LinkReceiver& link)
 {
 	switch (code) {
 		case AS_SHOW_WINDOW:
+		{
 			DTRACE(("ServerWindow %s: Message AS_SHOW_WINDOW\n", Title()));
 			_Show();
+
+			int32 showLevel;
+			if (link.Read<int32>(&showLevel) == B_OK) {
+				fWindow->SetShowLevel(showLevel);
+			}
 			break;
 
+		}
 		case AS_HIDE_WINDOW:
+		{
 			DTRACE(("ServerWindow %s: Message AS_HIDE_WINDOW\n", Title()));
 			_Hide();
-			break;
 
+			int32 showLevel;
+			if (link.Read<int32>(&showLevel) == B_OK) {
+				fWindow->SetShowLevel(showLevel);
+			}
+			break;
+		}
 		case AS_MINIMIZE_WINDOW:
 		{
-			int32 showLevel;
 			bool minimize;
 
-			link.Read<bool>(&minimize);
-			if (link.Read<int32>(&showLevel) == B_OK) {
+			if (link.Read<bool>(&minimize) == B_OK) {
 				DTRACE(("ServerWindow %s: Message AS_MINIMIZE_WINDOW, "
-					"showLevel: %ld, minimize: %d\n", Title(), showLevel,
-					minimize));
+					"minimize: %d\n", Title(), minimize));
 
-				if (showLevel <= 0) {
-					// window is currently hidden - ignore the minimize request
+				if (fWindow->ShowLevel() <= 0) {
+					// Window is currently hidden - ignore the minimize
+					// request, but keep the state in sync.
 					fWindow->SetMinimized(minimize);
-						// TODO: commenting this out makes BWindow::fMinimized
-						// and Window::fMinimized go out of sync. However, not
-						// doing it currently causes #4127.
 					break;
 				}
 

src/servers/app/Window.cpp

@@ -104,6 +104,7 @@ Window::Window(const BRect& frame, const char *name,
 
 	// windows start hidden
 	fHidden(true),
+	fShowLevel(0),
 	fMinimized(false),
 	fIsFocus(false),
 
@@ -1079,6 +1080,16 @@ Window::SetHidden(bool hidden)
 }
 
 
+void
+Window::SetShowLevel(int32 showLevel)
+{
+	if (showLevel == fShowLevel)
+		return;
+
+	fShowLevel = showLevel;
+}
+
+
 void
 Window::SetMinimized(bool minimized)
 {

src/servers/app/Window.h

@@ -210,6 +210,9 @@ public:
 			void				SetHidden(bool hidden);
 	inline	bool				IsHidden() const { return fHidden; }
 
+			void				SetShowLevel(int32 showLevel);
+	inline	int32				ShowLevel() const { return fShowLevel; }
+
 			void				SetMinimized(bool minimized);
 	inline	bool				IsMinimized() const { return fMinimized; }
 
@@ -410,6 +413,7 @@ protected:
 			bool				fUpdatesEnabled : 1;
 
 			bool				fHidden : 1;
+			int32				fShowLevel;
 			bool				fMinimized : 1;
 			bool				fIsFocus : 1;