BlockInjection

BlockInjection is a helpful library for iOS and Mac OS X.

You can insert some Blocks before and after the method by this library.

Samples

For example, if you use Google Analytics, you can embed the code for tracking without polluting your original source code.

#import "BILib.h"

[BILib injectToClass:[ViewController class] selector:@selector(buttonDidPush:) preprocess:^{

  // This code is called just before buttnDidPush:
  [tracker sendEventWithCategory:@"uiAction"
                      withAction:@"buttonDidPush"
                       withLabel:nil
                       withValue:0];

}];

You can use NSString instead of Selector and Class.

#import "BILib.h"

[BILib injectToClassWithName:@"ViewController" methodName:@"buttonDidPush:" preprocess:^{

  // This code is called just before buttnDidPush:
  [tracker sendEventWithCategory:@"uiAction"
                      withAction:@"buttonDidPush"
                       withLabel:nil
                       withValue:0];

}];

You can insert a Postprocess.

#import "BILib.h"

[BILib injectToClass:[ViewController class] selector:@selector(buttonDidPush:) postprocess:^{

  // This code is called just after buttnDidPush:
  [tracker sendEventWithCategory:@"uiAction"
                      withAction:@"buttonDidPush"
                       withLabel:nil
                       withValue:0];

}];

You can use a instance method's argument in your block.

#import "BILib.h"

// Sample class

@interface Bizz : NSObject
- (void)sayMessage:(NSString*)message;
@end 

@implementation Bizz
- (void)sayMessage:(NSString*)message
{
  NSLog(@"Bizz says: %@", message);
}
@end 

// ...

[BILib injectToClass:[Bizz class] selector:@selector(sayMessage:) preprocess:^(Bizz* bizz, NSString* message){

  // This code is called just before buttnDidPush:
  [tracker sendEventWithCategory:@"Bizz"
                      withAction:@"sayMessage"
                       withLabel:message //< You can use the argument that is passed to sayMessage:
                       withValue:0];

}];

// ...

You can use the regex for specifying the class names and the method names.

#import "BILib.h"

[BILib injectToClassWithNameRegex:BIRegex(@"^UIView$") methodNameRegex:BIRegex(@"^set.*$") preprocess:^{

  // This code is called just before all UIView's setters and log the actual method name
  NSLog(@"%@", [BILib prettyFunction]);

}];

You can skip after processes with return value.

#import "BILib.h"

[BILib injectToClassWithName:@"Sample" methodName:@"intValue" preprocess:^{

  int ret = 10;
  // skip after processes (orignal method and after preprocesses and postprocesses)
  [BILib skipAfterProcessesWithReturnValue:&ret];

}];

Getting Started - Installing BlockInjection

Please choose a way you prefer.

Using CocoaPods

// Podfile
pod 'BlockInjection'

and

pod install

Using Git

git clone git://github.com/tokorom/BlockInjection.git
// git submodule add git://github.com/tokorom/BlockInjection.git Externals/BlockInjection

and Add BlockInjection subdirectory to your Xcode's project.

Download a zip archive

Download
https://github.com/tokorom/BlockInjection/archive/master.zip
and Add BlockInjection subdirectory to your Xcode's project.