Finally implemented BWindow::CenterOnScreen, with associated CenterIn(BRect)

methods as well as Size(). To avoid the problem of centering the window before
it has been resized by the layout system, I force the resizing early. If there
is a better way to do this or some way to avoid doing it repeatedly, let me
know. But I figure the Center* methods should not be called that often.

Updated Screenshot and DiskProbe to use this new method as a test. It certainly
cleaned up DiskProbe. I will update other code over the next few days (if
anyone wants to help, please do :)


git-svn-id: file:///srv/svn/repos/haiku/haiku/trunk@32612 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/os/interface/Window.h

@@ -14,6 +14,7 @@
 #include <List.h>
 #include <Looper.h>
 #include <Rect.h>
+#include <Size.h>
 #include <StorageDefs.h>
 #include <View.h>
 
@@ -167,6 +168,10 @@ public:
 			void			ResizeBy(float dx, float dy);
 			void			ResizeTo(float width, float height);
 
+			void 			CenterIn(BRect* rect);
+			void 			CenterIn(BRect rect);
+			void 			CenterOnScreen();
+
 	virtual	void			Show();
 	virtual	void			Hide();
 			bool			IsHidden() const;
@@ -188,6 +193,7 @@ public:
 			BRect			Bounds() const;
 			BRect			Frame() const;
 			BRect			DecoratorFrame() const;
+			BSize			Size() const;
 			const char*		Title() const;
 			void			SetTitle(const char* title);
 			bool			IsFront() const;

src/apps/diskprobe/OpenWindow.cpp

@@ -57,22 +57,8 @@ OpenWindow::OpenWindow()
 		.Add(probeDeviceButton, 2, 1)
 		.SetInsets(8, 8, 8, 8)
 	);
-	BScreen screen(this);
-	// move the window offscreen..
-	MoveTo(screen.Frame().right+20, screen.Frame().top);
-	fCentered = true;
-}
 
-
+	CenterOnScreen();
-void
-OpenWindow::FrameResized(float width, float height)
-{
-	if (fCentered) {
-		BScreen screen(this);
-		MoveTo(screen.Frame().left + (screen.Frame().Width() - width) / 2,
-			screen.Frame().top + (screen.Frame().Height() - height) / 2);
-	}
-	fCentered = false;
 }
 
 

src/apps/diskprobe/OpenWindow.h

@@ -20,14 +20,11 @@ public:
 	virtual	void				MessageReceived(BMessage* message);
 	virtual	bool				QuitRequested();
 
-	virtual void				FrameResized(float width, float height);
-
 	static	void				CollectDevices(BMenu* menu,
 									BEntry* startEntry = NULL);
 
 private:
 			BMenu*				fDevicesMenu;
-			bool				fCentered;
 };
 
 #endif	/* OPEN_WINDOW_H */

src/apps/screenshot/ScreenshotWindow.cpp

@@ -492,12 +492,7 @@ ScreenshotWindow::_AddItemToPathMenu(const char* path, BString& label,
 void
 ScreenshotWindow::_CenterAndShow()
 {
-	BSize size = GetLayout()->PreferredSize();
+	CenterOnScreen();
-	ResizeTo(size.Width(), size.Height());
-
-	BRect frame(BScreen(this).Frame());
-	MoveTo((frame.Width() - size.Width()) / 2.0,
-		(frame.Height() - size.Height()) / 2.0);
 
 	Show();
 }

src/kits/interface/Window.cpp

@@ -21,6 +21,8 @@
 #include <Bitmap.h>
 #include <Button.h>
 #include <FindDirectory.h>
+#include <Layout.h>
+#include <LayoutUtils.h>
 #include <MenuBar.h>
 #include <MenuItem.h>
 #include <MessageQueue.h>
@@ -2026,6 +2028,13 @@ BWindow::DecoratorFrame() const
 }
 
 
+BSize
+BWindow::Size() const
+{
+	return BSize(fFrame.Width(), fFrame.Height());
+}
+
+
 const char*
 BWindow::Title() const
 {
@@ -2448,6 +2457,36 @@ BWindow::ResizeTo(float width, float height)
 }
 
 
+void
+BWindow::CenterIn(BRect rect)
+{
+	// Force layout resizing if needed
+	if (GetLayout() != NULL) {
+		BSize size = GetLayout()->PreferredSize();
+		ResizeTo(size.Width(), size.Height());
+	}
+
+	MoveTo(BLayoutUtils::AlignInFrame(rect, Size(), 
+		BAlignment(B_ALIGN_HORIZONTAL_CENTER,
+			B_ALIGN_VERTICAL_CENTER)).LeftTop());
+}
+
+
+void
+BWindow::CenterIn(BRect* rect)
+{
+	CenterIn(*rect);
+}
+
+
+void
+BWindow::CenterOnScreen()
+{
+	BScreen screen(this);
+	CenterIn(screen.Frame());
+}
+
+
 void
 BWindow::Show()
 {