Implemented Group on Mac OS X.

redo/basicctrls_darwin.m

@@ -6,6 +6,8 @@
 
 #define toNSButton(x) ((NSButton *) (x))
 #define toNSTextField(x) ((NSTextField *) (x))
+#define toNSView(x) ((NSView *) (x))
+#define toNSBox(x) ((NSBox *) (x))
 
 @interface goControlDelegate : NSObject {
 @public
@@ -156,3 +158,28 @@ id newLabel(void)
 	[l setDrawsBackground:NO];
 	return finishNewTextField(l, NO);
 }
+
+id newGroup(id container)
+{
+	NSBox *group;
+
+	group = [[NSBox alloc] initWithFrame:NSZeroRect];
+	[group setBorderType:NSLineBorder];
+	[group setBoxType:NSBoxPrimary];
+	[group setTransparent:NO];
+	// can't use setSmallControlFont() here because the selector is different
+	[group setTitleFont:[NSFont systemFontOfSize:[NSFont systemFontSizeForControlSize:NSSmallControlSize]]];
+	[group setTitlePosition:NSAtTop];
+	[group setContentView:toNSView(container)];
+	return (id) group;
+}
+
+const char *groupText(id group)
+{
+	return [[toNSBox(group) title] UTF8String];
+}
+
+void groupSetText(id group, char *text)
+{
+	[toNSBox(group) setTitle:[NSString stringWithUTF8String:text]];
+}

redo/control_darwin.m

@@ -28,7 +28,7 @@ void setSmallControlFont(id control)
 	[toNSControl(control) setFont:[NSFont systemFontOfSize:[NSFont systemFontSizeForControlSize:NSSmallControlSize]]];
 }
 
-// also good for NSProgressIndicator
+// also good for NSBox and NSProgressIndicator
 struct xsize controlPreferredSize(id control)
 {
 	NSControl *c;

redo/group_darwin.go

@@ -0,0 +1,58 @@
+// 16 august 2014
+
+package ui
+
+import (
+	"unsafe"
+)
+
+// #include "objc_darwin.h"
+import "C"
+
+type group struct {
+	_id		C.id
+
+	*container
+}
+
+func newGroup(text string, control Control) Group {
+	g := new(group)
+	g.container = newContainer(control)
+	g._id = C.newGroup(g.container.id)
+	g.SetText(text)
+	return g
+}
+
+func (g *group) Text() string {
+	return C.GoString(C.groupText(g._id))
+}
+
+func (g *group) SetText(text string) {
+	ctext := C.CString(text)
+	defer C.free(unsafe.Pointer(ctext))
+	C.groupSetText(g._id, ctext)
+}
+
+func (g *group) id() C.id {
+	return g._id
+}
+
+func (g *group) setParent(p *controlParent) {
+	basesetParent(g, p)
+}
+
+func (g *group) allocate(x int, y int, width int, height int, d *sizing) []*allocation {
+	return baseallocate(g, x, y, width, height, d)
+}
+
+func (g *group) preferredSize(d *sizing) (width, height int) {
+	return basepreferredSize(g, d)
+}
+
+func (g *group) commitResize(a *allocation, d *sizing) {
+	basecommitResize(g, a, d)
+}
+
+func (g *group) getAuxResizeInfo(d *sizing) {
+	basegetAuxResizeInfo(g, d)
+}

redo/objc_darwin.h

@@ -69,6 +69,9 @@ extern id newPasswordField(void);
 extern const char *textFieldText(id);
 extern void textFieldSetText(id, char *);
 extern id newLabel(void);
+extern id newGroup(id);
+extern const char *groupText(id);
+extern void groupSetText(id, char *);
 
 /* container_darwin.m */
 extern id newContainerView(void *);