Make it possible to have implementations in different toolkits.

Also, make it possible to share the headers.

headers/OGApplication.h

@@ -0,0 +1,23 @@
+#include <gtk/gtk.h>
+
+#import <ObjFW/ObjFW.h>
+
+@protocol OGApplicationDelegate <OFObject>
+- (void)applicationDidFinishLaunching;
+@optional
+- (void)applicationWillTerminate;
+@end
+
+@interface OGApplication: OFObject <OFApplicationDelegate>
+{
+	id <OFApplicationDelegate> delegate;
+}
+
++ (void)quit;
+@end
+
+#define OG_APPLICATION_DELEGATE(cls)	\
+	Class				\
+	og_application_delegate() {	\
+		return [cls class];	\
+	}

headers/OGBox.h

@@ -0,0 +1,14 @@
+#import "OGWidget.h"
+
+@interface OGBox: OGWidget
++ box;
+
+- (void)appendChild: (OGWidget*)child
+	     expand: (BOOL)expand
+	       fill: (BOOL)fill
+	    padding: (float)padding;
+- (void)prependChild: (OGWidget*)child
+	      expand: (BOOL)expand
+		fill: (BOOL)fill
+	     padding: (float)padding;
+@end

headers/OGButton.h

@@ -0,0 +1,19 @@
+#import "OGWidget.h"
+
+@class OGButton;
+
+@protocol OGButtonDelegate <OFObject>
+@optional
+- (void)buttonWasClicked: (OGButton*)button;
+@end
+
+@interface OGButton: OGWidget
+{
+	id <OGButtonDelegate> delegate;
+}
+
+@property (assign) id <OGButtonDelegate> delegate;
+@property (copy) OFString *label;
+
++ button;
+@end

headers/OGHBox.h

@@ -0,0 +1,4 @@
+#import "OGBox.h"
+
+@interface OGHBox: OGBox
+@end

headers/OGVBox.h

@@ -0,0 +1,4 @@
+#import "OGBox.h"
+
+@interface OGVBox: OGBox
+@end

headers/OGWidget.h

@@ -0,0 +1,15 @@
+#include <gtk/gtk.h>
+
+#import <ObjFW/ObjFW.h>
+
+@interface OGWidget: OFObject
+{
+@public
+	GtkWidget *widget;
+}
+
+- (void)show;
+- (void)hide;
+@end
+
+extern void og_destroy(GtkWidget*, OGWidget*);

headers/OGWindow.h

@@ -0,0 +1,22 @@
+#import "OGWidget.h"
+
+@class OGWindow;
+
+@protocol OGWindowDelegate <OFObject>
+@optional
+- (BOOL)windowWillClose: (OGWindow*)window;
+@end
+
+@interface OGWindow: OGWidget
+{
+	id <OGWindowDelegate> delegate;
+}
+
+@property (assign) id <OGWindowDelegate> delegate;
+@property (copy) OFString *title;
+@property (assign) of_point_t position;
+@property (assign) of_dimension_t dimension;
+
++ window;
+- (void)addChild: (OGWidget*)widget;
+@end