Refactored the shortcut dispatcher and bindings to user defaults.

This is a big change that was hard to split into smaller commits. There’s now
a new class to bind shortcuts to actions, a new class to bind user defaults’
keys to actions, and a new way to associate user defaults with the recorder
control (MASShortcutView). I have also updated the demo app to go with the
changes.

The new class to associate shortcuts with actions is called MASShortcutMonitor.
It wraps the Carbon hotkey magic and offers a simple interface to add a
shortcut along with a block that should be run when the shortcut is pressed.
It’s the lowest-level interface.

Since the usual requirement is to store the shortcuts into user defaults,
there’s also a higher-level interface offered by the MASShortcutBinder class.
That takes a defaults key and associates it with a block. When the shortcut
stored under the defaults key changes, the binder automatically switches to the
new shortcut. The class is a wrapper built atop of the previous one, the
MASShortcutMonitor – it simply adds, updates and removes shortcuts as the
user defaults change.

I have removed the special user defaults integration code from the recorder
control (MASShortcutView) and replaced it with a small Cocoa Bindings shim.
This means that in order to keep the recorder control in sync with the defaults
you just have to call the usual bind:toObject:withKeyPath:options: method,
like this:

[_shortcutView bind:MASShortcutBinding
    toObject:[NSUserDefaultsController sharedUserDefaultsController]
    withKeyPath[@"values.ExampleDefaultsKey"
    options:@{NSValueTransformerNameBindingOption:NSKeyedUnarchiveFromDataTransformerName}];

That’s more verbose than the previous solution, but it’s much cleaner and can
be swept under a convenience call if needed. I might also add a dictionaryValue
property later that would make it possible to bind the value to user defaults
directly, without a transformer, and would enable backward compatibility with
Shortcut Recorder.

1 files changed, 0 insertions, 125 deletions

diff --git a/Framework/MASShortcutView+UserDefaults.m b/Framework/MASShortcutView+UserDefaults.m
deleted file mode 100644
index 55584f4..0000000
--- a/Framework/MASShortcutView+UserDefaults.m
+++ /dev/null
@@ -1,125 +0,0 @@
-#import "MASShortcutView+UserDefaults.h"
-#import "MASShortcut.h"
-#import <objc/runtime.h>
-
-@interface MASShortcutDefaultsObserver : NSObject
-
-@property (nonatomic, readonly) NSString *userDefaultsKey;
-@property (nonatomic, readonly, weak) MASShortcutView *shortcutView;
-
-- (id)initWithShortcutView:(MASShortcutView *)shortcutView userDefaultsKey:(NSString *)userDefaultsKey;
-
-@end
-
-#pragma mark -
-
-@implementation MASShortcutView (UserDefaults)
-
-void *MASAssociatedDefaultsObserver = &MASAssociatedDefaultsObserver;
-
-- (NSString *)associatedUserDefaultsKey
-{
-    MASShortcutDefaultsObserver *defaultsObserver = objc_getAssociatedObject(self, MASAssociatedDefaultsObserver);
-    return defaultsObserver.userDefaultsKey;
-}
-
-- (void)setAssociatedUserDefaultsKey:(NSString *)associatedUserDefaultsKey
-{
-    // First, stop observing previous shortcut view
-    objc_setAssociatedObject(self, MASAssociatedDefaultsObserver, nil, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
-
-    if (associatedUserDefaultsKey.length == 0) return;
-
-    // Next, start observing current shortcut view
-    MASShortcutDefaultsObserver *defaultsObserver = [[MASShortcutDefaultsObserver alloc] initWithShortcutView:self userDefaultsKey:associatedUserDefaultsKey];
-    objc_setAssociatedObject(self, MASAssociatedDefaultsObserver, defaultsObserver, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
-}
-
-@end
-
-#pragma mark -
-
-@implementation MASShortcutDefaultsObserver {
-    MASShortcut *_originalShortcut;
-    BOOL _internalPreferenceChange;
-    BOOL _internalShortcutChange;
-}
-
-- (id)initWithShortcutView:(MASShortcutView *)shortcutView userDefaultsKey:(NSString *)userDefaultsKey
-{
-    self = [super init];
-    if (self) {
-        _originalShortcut = shortcutView.shortcutValue;
-        _shortcutView = shortcutView;
-        _userDefaultsKey = userDefaultsKey.copy;
-        [self startObservingShortcutView];
-    }
-    return self;
-}
-
-- (void)dealloc
-{
-    // __weak _shortcutView is not yet deallocated because it refers MASShortcutDefaultsObserver
-    [self stopObservingShortcutView];
-}
-
-#pragma mark -
-
-void *kShortcutValueObserver = &kShortcutValueObserver;
-
-- (void)startObservingShortcutView
-{
-    // Read initial shortcut value from user preferences
-    NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
-    NSData *data = [defaults dataForKey:_userDefaultsKey];
-    _shortcutView.shortcutValue = [NSKeyedUnarchiver unarchiveObjectWithData:data];
-
-    // Observe user preferences to update shortcut value when it changed
-    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(userDefaultsDidChange:) name:NSUserDefaultsDidChangeNotification object:defaults];
-
-    // Observe the keyboard shortcut that user inputs by hand
-    [_shortcutView addObserver:self forKeyPath:@"shortcutValue" options:0 context:kShortcutValueObserver];
-}
-
-- (void)userDefaultsDidChange:(NSNotification *)note
-{
-    // Ignore notifications posted from -[self observeValueForKeyPath:]
-    if (_internalPreferenceChange) return;
-
-    _internalShortcutChange = YES;
-    NSData *data = [note.object dataForKey:_userDefaultsKey];
-    _shortcutView.shortcutValue = [NSKeyedUnarchiver unarchiveObjectWithData:data];
-    _internalShortcutChange = NO;
-}
-
-- (void)stopObservingShortcutView
-{
-    // Stop observing keyboard hotkeys entered by user in the shortcut view
-    [_shortcutView removeObserver:self forKeyPath:@"shortcutValue" context:kShortcutValueObserver];
-
-    // Stop observing user preferences
-    [[NSNotificationCenter defaultCenter] removeObserver:self name:NSUserDefaultsDidChangeNotification object:[NSUserDefaults standardUserDefaults]];
-
-    // Restore original hotkey in the shortcut view
-    _shortcutView.shortcutValue = _originalShortcut;
-}
-
-- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context
-{
-    if (context == kShortcutValueObserver) {
-        if (_internalShortcutChange) return;
-        MASShortcut *shortcut = [object valueForKey:keyPath];
-        _internalPreferenceChange = YES;
-
-        NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
-        [defaults setObject:[NSKeyedArchiver archivedDataWithRootObject:shortcut] forKey:_userDefaultsKey];
-        [defaults synchronize];
-
-        _internalPreferenceChange = NO;
-    }
-    else {
-        [super observeValueForKeyPath:keyPath ofObject:object change:change context:context];
-    }
-}
-
-@end