1 files changed, 105 insertions, 0 deletions
diff --git a/combobox_darwin.m b/combobox_darwin.m
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+++ b/combobox_darwin.m
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+// 17 may 2014
+
+#include "objc_darwin.h"
+#import <AppKit/NSPopUpButton.h>
+#import <AppKit/NSComboBox.h>
+#import <AppKit/NSArrayController.h>
+
+/*
+Cocoa doesn't have combo boxes in the sense that other systems do. NSPopUpButton is not editable and technically behaves like a menu on a menubar. NSComboBox is editable and is the more traditional combo box, but the edit field and list are even more separated than they are on other platforms.
+
+Unfortunately, their default internal storage mechanisms exhibit the automatic selection behavior I DON'T want, so we're going to have to do that ourselves.
+
+The NSArrayController we use in our Listboxes already behaves the way we want. Consequently, you'll notice a bunch of functions here call functions in listbox_darwin.m. How convenient =P (TODO separate into objc_darwin.m?)
+
+TODO should we use NSComboBox's dataSource feature?
+*/
+
+extern NSRect dummyRect;
+
+#define to(T, x) ((T *) (x))
+#define toNSPopUpButton(x) to(NSPopUpButton, (x))
+#define toNSComboBox(x) to(NSComboBox, (x))
+
+#define toNSInteger(x) ((NSInteger) (x))
+#define fromNSInteger(x) ((intptr_t) (x))
+
+#define COMBOBOXKEY @"cbitem"
+static NSString *comboboxKey = COMBOBOXKEY;
+static NSString *comboboxBinding = @"contentValues";
+static NSString *comboboxKeyPath = @"arrangedObjects." COMBOBOXKEY;
+
+id makeCombobox(BOOL editable)
+{
+	NSArrayController *ac;
+
+	ac = makeListboxArray();
+#define BIND bind:comboboxBinding toObject:ac withKeyPath:comboboxKeyPath options:nil
+// for NSPopUpButton, we need a little extra work to make it respect the NSArrayController's selection behavior properties
+// thanks to stevesliva (http://stackoverflow.com/questions/23715275/cocoa-how-do-i-suppress-nspopupbutton-automatic-selection-synchronization-nsar)
+// note: selectionIndex isn't listed in the Cocoa Bindings Reference for NSArrayController under exposed bindings, but is in the Cocoa Bindings Programming Topics under key-value observant properties, so we can still bind to it
+#define BINDSEL bind:@"selectedIndex" toObject:ac withKeyPath:@"selectionIndex" options:nil
+
+	if (!editable) {
+		NSPopUpButton *pb;
+
+		pb = [[NSPopUpButton alloc]
+			initWithFrame:dummyRect
+			pullsDown:NO];
+		[pb BIND];
+		[pb BINDSEL];
+		return pb;
+	}
+
+	NSComboBox *cb;
+
+	cb = [[NSComboBox alloc]
+		initWithFrame:dummyRect];
+	[cb setUsesDataSource:NO];
+	[cb BIND];
+	// no need to bind selection
+	return cb;
+}
+
+id comboboxText(id c, BOOL editable)
+{
+	if (!editable)
+		return [toNSPopUpButton(c) titleOfSelectedItem];
+	return [toNSComboBox(c) stringValue];
+}
+
+void comboboxAppend(id c, BOOL editable, id str)
+{
+	id ac;
+
+	ac = boundListboxArray(c, comboboxBinding);
+	listboxArrayAppend(ac, toListboxItem(comboboxKey, str));
+}
+
+void comboboxInsertBefore(id c, BOOL editable, id str, intptr_t before)
+{
+	id ac;
+
+	ac = boundListboxArray(c, comboboxBinding);
+	listboxArrayInsertBefore(ac, toListboxItem(comboboxKey, str), before);
+}
+
+intptr_t comboboxSelectedIndex(id c)
+{
+	// both satisfy the selector
+	return fromNSInteger([toNSPopUpButton(c) indexOfSelectedItem]);
+}
+
+void comboboxDelete(id c, intptr_t index)
+{
+	id ac;
+
+	ac = boundListboxArray(c, comboboxBinding);
+	listboxArrayDelete(ac, index);
+}
+
+intptr_t comboboxLen(id c)
+{
+	// both satisfy the selector
+	return fromNSInteger([toNSPopUpButton(c) numberOfItems]);
+}