libui/darwin/combobox.m

// 14 august 2015
#include "uipriv_darwin.h"

struct uiCombobox {
	uiDarwinControl c;
	BOOL editable;
	NSPopUpButton *pb;
	NSArrayController *pbac;
	NSComboBox *cb;
	NSObject *handle;				// for uiControlHandle()
	void (*onSelected)(uiCombobox *, void *);
	void *onSelectedData;
};

@interface comboboxDelegateClass : NSObject<NSComboBoxDelegate> {
	NSMapTable *comboboxes;
}
- (void)comboBoxSelectionDidChange:(NSNotification *)note;
- (IBAction)onSelected:(id)sender;
- (void)registerCombobox:(uiCombobox *)c;
- (void)unregisterCombobox:(uiCombobox *)c;
@end

@implementation comboboxDelegateClass

- (id)init
{
	self = [super init];
	if (self)
		self->comboboxes = newMap();
	return self;
}

- (void)dealloc
{
	if ([self->comboboxes count] != 0)
		complain("attempt to destroy shared combobox delegate but comboboxes are still registered to it");
	[self->comboboxes release];
	[super dealloc];
}

// note: does not trigger when text changed
// TODO not perfect either:
// - triggered when keyboard navigating the open menu
// - does not trigger when the text is changed to a menu item (which normally selects that item; IDK how to inhibit that behavior - TODO)
- (void)comboBoxSelectionDidChange:(NSNotification *)note
{
	[self onSelected:[note object]];
}

- (IBAction)onSelected:(id)sender
{
	uiCombobox *c;

	c = (uiCombobox *) mapGet(self->comboboxes, sender);
	(*(c->onSelected))(c, c->onSelectedData);
}

- (void)registerCombobox:(uiCombobox *)c
{
	mapSet(self->comboboxes, c->handle, c);
	if (c->editable)
		[c->cb setDelegate:self];
	else {
		[c->pb setTarget:self];
		[c->pb setAction:@selector(onSelected:)];
	}
}

- (void)unregisterCombobox:(uiCombobox *)c
{
	if (c->editable)
		[c->cb setDelegate:nil];
	else
		[c->pb setTarget:nil];
	[self->comboboxes removeObjectForKey:c->handle];
}

@end

static comboboxDelegateClass *comboboxDelegate = nil;

static void onDestroy(uiCombobox *);

uiDarwinDefineControlWithOnDestroy(
	uiCombobox,							// type name
	uiComboboxType,						// type function
	handle,								// handle
	onDestroy(this);						// on destroy
)

static void onDestroy(uiCombobox *c)
{
	[comboboxDelegate unregisterCombobox:c];
	if (!c->editable) {
		[c->pb unbind:@"contentObjects"];
		[c->pb unbind:@"selectedIndex"];
		[c->pbac release];
	}
}

void uiComboboxAppend(uiCombobox *c, const char *text)
{
	if (c->editable)
		[c->cb addItemWithObjectValue:toNSString(text)];
	else
		[c->pbac addObject:toNSString(text)];
}

intmax_t uiComboboxSelected(uiCombobox *c)
{
	if (c->editable)
		return [c->cb indexOfSelectedItem];
	return [c->pb indexOfSelectedItem];
}

void uiComboboxOnSelected(uiCombobox *c, void (*f)(uiCombobox *c, void *data), void *data)
{
	c->onSelected = f;
	c->onSelectedData = data;
}

static void defaultOnSelected(uiCombobox *c, void *data)
{
	// do nothing
}

static uiCombobox *finishNewCombobox(BOOL editable)
{
	uiCombobox *c;

	c = (uiCombobox *) uiNewControl(uiComboboxType());

	c->editable = editable;
	if (c->editable) {
		c->cb = [[NSComboBox alloc] initWithFrame:NSZeroRect];
		[c->cb setUsesDataSource:NO];
		[c->cb setButtonBordered:YES];
		[c->cb setCompletes:NO];
		uiDarwinSetControlFont(c->cb, NSRegularControlSize);
		c->handle = c->cb;
	} else {
		NSPopUpButtonCell *pbcell;

		c->pb = [[NSPopUpButton alloc] initWithFrame:NSZeroRect pullsDown:NO];
		[c->pb setPreferredEdge:NSMinYEdge];
		pbcell = (NSPopUpButtonCell *) [c->pb cell];
		[pbcell setArrowPosition:NSPopUpArrowAtBottom];
		// TODO font
		c->handle = c->pb;

		// NSPopUpButton doesn't work like a combobox
		// - it automatically selects the first item
		// - it doesn't support duplicates
		// but we can use a NSArrayController and Cocoa bindings to bypass these restrictions
		c->pbac = [NSArrayController new];
		[c->pbac setAvoidsEmptySelection:NO];
		[c->pbac setSelectsInsertedObjects:NO];
		[c->pbac setAutomaticallyRearrangesObjects:NO];
		[c->pb bind:@"contentValues"
			toObject:c->pbac
			withKeyPath:@"arrangedObjects"
			options:nil];
		[c->pb bind:@"selectedIndex"
			toObject:c->pbac
			withKeyPath:@"selectionIndex"
			options:nil];
	}

	if (comboboxDelegate == nil) {
		comboboxDelegate = [comboboxDelegateClass new];
		[delegates addObject:comboboxDelegate];
	}
	[comboboxDelegate registerCombobox:c];
	uiComboboxOnSelected(c, defaultOnSelected, NULL);

	uiDarwinFinishNewControl(c, uiCombobox);

	return c;
}

uiCombobox *uiNewCombobox(void)
{
	return finishNewCombobox(NO);
}

uiCombobox *uiNewEditableCombobox(void)
{
	return finishNewCombobox(YES);
}