GCD is a lightweight Cocoa wrapper aiming at easing development with Grand Central Dispatch. It does support some common usage patterns, it does not wrap the whole functionality; a basic understanding of how CGD works is necessary and is not addressed on this document.
Easily create you own queues, or access global ones
+ (GCDQueue*)serial:(NSString*)name; + (GCDQueue*)concurrent:(NSString*)name; + (GCDQueue*)main; + (GCDQueue*)queue; + (GCDQueue*)high; + (GCDQueue*)low; + (GCDQueue*)background;
Set the target queue, suspend or resume execution
- (void)setTarget:(GCDQueue*)q; - (void)suspend; - (void)resume;
Queue blocks for execution (optionally delayed or repeated) or set a barrier to synchronize concurrent ones
- (void)add:(dispatch_block_t)block; - (void)add:(dispatch_block_t)block delay:(float)t; - (void)add:(dispatch_block_repeated_t)block times:(NSUInteger)times; - (void)barrier:(dispatch_block_t)block;
Context information can be set and retrieved through Obj-C subscripting from the queue. objectForKey: retrieves context from the current queue so it can be used from a block without external references.
- (void)setObject:(id)anObject forKeyedSubscript:(id)aKey; - (id)objectForKeyedSubscript:(id)aKey; + (id)objectForKey:(id)aKey;
Create, label, suspend, resume or clear a group with a comfortable syntax.
+ (GCDGroup*)group; @property (nonatomic,readwrite,strong) NSString* label; - (void)suspend; - (void)resume; - (void)empty;
You can choose to add blocks to a specific queue, or they will be added to the global queue.
- (void)add:(dispatch_block_t)block; - (void)add:(dispatch_block_t)block queue:(GCDQueue*)queue;
To manage a block execution you can set a notification block to be executed when previously submitted blocks have executed, or wait synchronously for termination.
- (void)notify:(dispatch_block_t)block; - (void)notify:(dispatch_block_t)block target:(GCDQueue*)queue;
I'm Max Raber. @raberm on Twitter.
Questions about the code should be left as issues at https://github.com/raberm/GCD or message me on Twitter.
None beyond Foundation.
Copyright © 2012-2014 Massimiliano Raber
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