Ecosyste.ms: Awesome
An open API service indexing awesome lists of open source software.
https://github.com/alejandro-isaza/MultiDelegate
Objective-C delegate multiplexing
https://github.com/alejandro-isaza/MultiDelegate
delegate-multiplexer objective-c
Last synced: about 1 month ago
JSON representation
Objective-C delegate multiplexing
- Host: GitHub
- URL: https://github.com/alejandro-isaza/MultiDelegate
- Owner: alejandro-isaza
- License: mit
- Created: 2013-03-18T21:42:12.000Z (over 11 years ago)
- Default Branch: master
- Last Pushed: 2021-10-02T17:11:37.000Z (over 2 years ago)
- Last Synced: 2024-05-18T07:10:15.013Z (about 1 month ago)
- Topics: delegate-multiplexer, objective-c
- Language: Objective-C
- Size: 40 KB
- Stars: 129
- Watchers: 7
- Forks: 18
- Open Issues: 1
-
Metadata Files:
- Readme: README.md
- License: LICENSE
Lists
- awesome-ios - MultiDelegate
README
MultiDelegate
=============
MultiDelegate is a delegate multiplexing class for Objective-C. In other words, it will dispatch delegate methods to multiple objects, instead of being restricted to a single delegate object. You can also use it as a generic method dispatch mechanism. For more information see the [blog post](http://a-coding.com/delegate-multiplexing/).
[](https://travis-ci.org/aleph7/MultiDelegate)
## Example
Suppose you have a `UITableView` and you want to implement the data source using two separate classes: one is the actual data source implementing the `tableView:numberOfRowsInSection:` method and the other one is the cell factory implementing the `tableView:cellForRowAtIndexPath:` method to construct the cells.
First create an `AIMultiDelegate` instance. You need to keep a strong reference to this instance because most objects don't retain their delegates:
```objc
_multiDelegate = [[AIMultiDelegate alloc] init];
```
Then add all the actual delegates to the `_multiDelegate` object:
```
[_multiDelegate addDelegate:self];
[_multiDelegate addDelegate:_dataSource];
```
Finally set the table's data source as the delegate multiplexer:
```
self.tableView.dataSource = (id)_multiDelegate;
```
See the example project for the full source.
## Remarks
Keep this in mind
* Every method invocation will be forwarded to each object in the list in the order they were added.
* If a method returns a value the return value will be from the last object that responded to the method. For example if object `A` implements method `getInt` by returning `1`, object `B` implements `getInt` by returning `2` and object `C` doesn't implement `getInt`, calling `getInt` on an `AIMultiDelegate` containing `A`, `B` and `C` (in that order) will return `2`.
* `AIMultiDelegate` doesn't keep strong references to the objects added to it.
* Some objects only call `respondsToSelector:` when you first set the delegate to improve performance, so make sure you add all your delegates to the `AIMultiDelegate` before you set it as the delegate.
## Installation
If you are using [CocoaPods](https://github.com/cocoapods/cocoapods), add this to your `Podfile`:
```ruby
pod 'MultiDelegate'
```
Otherwise add `AIMultiDelegate.h/.m` to your project.