jens@0: //
jens@0: //  KVUtils.m
jens@0: //  MYUtilities
jens@0: //
jens@0: //  Created by Jens Alfke on 2/25/08.
jens@0: //  Copyright 2008 Jens Alfke. All rights reserved.
jens@0: //
jens@0: 
jens@0: #import "KVUtils.h"
jens@0: 
jens@0: 
jens@0: @implementation Observance
jens@0: 
jens@0: - (id) initWithTarget: (id)target 
jens@0:                action: (SEL)action
jens@0:              observed: (id)observed
jens@0:               keyPath: (NSString*)keyPath 
jens@0:               options: (NSKeyValueObservingOptions)options
jens@0: {
jens@0:     self = [super init];
jens@0:     if (self != nil) {
jens@0:         _target = target;
jens@0:         _action = action;
jens@0:         _observed = observed;
jens@0:         _keyPath = [keyPath copy];
jens@0:         _options = options;
jens@0:         
jens@0:         options &= ~(MYKeyValueObservingOptionOnce | MYKeyValueObservingOptionDelayed);
jens@0:         
jens@0:         [_observed addObserver: self forKeyPath: _keyPath options: options context: _action];
jens@0:     }
jens@0:     return self;
jens@0: }
jens@0: 
jens@0: - (void) dealloc
jens@0: {
jens@0:     [_observed removeObserver: self forKeyPath: _keyPath];
jens@0:     [_keyPath release];
jens@0:     [super dealloc];
jens@0: }
jens@0: 
jens@0: 
jens@0: @synthesize observed=_observed, keyPath=_keyPath;
jens@0: 
jens@0: 
jens@0: - (void) stopObserving
jens@0: {
jens@0:     [_observed removeObserver: self forKeyPath: _keyPath];
jens@0:     _observed = nil;
jens@0:     _target = nil;
jens@0:     _action = NULL;
jens@0: }
jens@0: 
jens@0: 
jens@0: - (void) _callTargetWithChange: (NSDictionary*)change
jens@0: {
jens@0:     @try{
jens@0:         [_target performSelector: _action withObject: _observed withObject: change];
jens@0:     }@catch( NSException *x ) {
jens@0:         Warn(@"Uncaught exception in -[%@<%p> %s] while observing change of key-path %@ in %@<%p>: %@",
jens@0:              _target,_target, _action, _keyPath, _observed,_observed, x);
jens@3:         [NSApp reportException: x];
jens@0:     }
jens@0: }
jens@0: 
jens@0: 
jens@0: - (void)observeValueForKeyPath:(NSString *)keyPath 
jens@0:                       ofObject:(id)object 
jens@0:                         change:(NSDictionary *)change 
jens@0:                        context:(void *)context
jens@0: {
jens@0:     if( object == _observed ) {
jens@0:         if( _options & MYKeyValueObservingOptionDelayed )
jens@0:             [self performSelector: @selector(_callTargetWithChange:) withObject: change
jens@0:                        afterDelay: 0.0];
jens@0:         else
jens@0:             [self _callTargetWithChange: change];
jens@0:         if( _options & MYKeyValueObservingOptionOnce )
jens@0:             [self stopObserving];
jens@0:     }
jens@0: }
jens@0: 
jens@0: 
jens@0: @end
jens@0: 
jens@0: 
jens@0: 
jens@0: 
jens@0: @implementation Observer
jens@0: 
jens@0: 
jens@0: - (id) init
jens@0: {
jens@0:     return [self initWithTarget: self];
jens@0: }
jens@0: 
jens@0: 
jens@0: 
jens@0: - (id) initWithTarget: (id)target
jens@0: {
jens@0:     Assert(target);
jens@0:     self = [super init];
jens@0:     if (self != nil) {
jens@0:         _target = target;
jens@0:         _observances = [[NSMutableArray alloc] init];
jens@0:     }
jens@0:     return self;
jens@0: }
jens@0: 
jens@0: 
jens@0: - (void) dealloc
jens@0: {
jens@0:     [self stopObserving];
jens@0:     [_observances release];
jens@0:     [super dealloc];
jens@0: }
jens@0: 
jens@0: 
jens@0: @synthesize target=_target;
jens@0: 
jens@0: 
jens@0: - (void) observe: (id)observed 
jens@0:          keyPath: (NSString*)keyPath 
jens@0:          options: (NSKeyValueObservingOptions)options
jens@0:           action: (SEL)action
jens@0: {
jens@0:     Observance *o = [[Observance alloc] initWithTarget: _target
jens@0:                                                 action: action
jens@0:                                               observed: observed
jens@0:                                                keyPath: keyPath
jens@0:                                                options: options];
jens@0:     [_observances addObject: o];
jens@0:     [o release];
jens@0: }
jens@0: 
jens@0: 
jens@0: - (void) observe: (id)observed 
jens@0:          keyPath: (NSString*)keyPath 
jens@0:           action: (SEL)action
jens@0: {
jens@0:     [self observe: observed keyPath: keyPath options: 0 action: action];
jens@0: }
jens@0: 
jens@0: 
jens@0: - (void) stopObserving
jens@0: {
jens@0:     [_observances makeObjectsPerformSelector: @selector(stopObserving)];
jens@0:     [_observances removeAllObjects];
jens@0: }
jens@0: 
jens@0: 
jens@3: - (void) stopObserving: (id)observed
jens@3: {
jens@3:     [self stopObserving: observed keyPath: nil];
jens@3: }
jens@3: 
jens@3: 
jens@0: - (void) stopObserving: (id)observed keyPath: (NSString*)keyPath
jens@0: {
jens@0:     // observed or keyPath may be nil
jens@0:     for( int i=_observances.count-1; i>=0; i-- ) {
jens@0:         Observance *o = [_observances objectAtIndex: i];
jens@0:         if( (observed==nil || observed==o.observed) && (keyPath==nil || [keyPath isEqual: o.keyPath]) ) {
jens@0:             [o stopObserving];
jens@0:             [_observances removeObjectAtIndex: i];
jens@0:         }
jens@0:     }
jens@0: }
jens@0: 
jens@0: @end
jens@11: 
jens@11: 
jens@11: /*
jens@11:  Copyright (c) 2008, Jens Alfke <jens@mooseyard.com>. All rights reserved.
jens@11:  
jens@11:  Redistribution and use in source and binary forms, with or without modification, are permitted
jens@11:  provided that the following conditions are met:
jens@11:  
jens@11:  * Redistributions of source code must retain the above copyright notice, this list of conditions
jens@11:  and the following disclaimer.
jens@11:  * Redistributions in binary form must reproduce the above copyright notice, this list of conditions
jens@11:  and the following disclaimer in the documentation and/or other materials provided with the
jens@11:  distribution.
jens@11:  
jens@11:  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR
jens@11:  IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND 
jens@11:  FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRI-
jens@11:  BUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
jens@11:  (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR 
jens@11:   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 
jens@11:  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF 
jens@11:  THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
jens@11:  */