获取app中firstResponder对象

UIResponder+FirstResponder.h

//
//  UIResponder+FirstResponder.h
//
//  Created by manjun.han on 13-4-18.
//  Copyright (c) 2013年 com.hmj. All rights reserved.
//

#import <UIKit/UIKit.h>

@interface UIResponder (FirstResponder)

-(void)setYourselfToGlobalFirstResponder ;

@property (nonatomic , weak) id currentFirstResponder ;

+ (id)currentFirstResponder ;

@end

UIResponder+FirstResponder.m

//
//  UIResponder+FirstResponder.m
//
//  Created by manjun.han on 13-4-18.
//  Copyright (c) 2013年 com.hmj. All rights reserved.
//

#import "UIResponder+FirstResponder.h"

static __weak id currentFirstResponder;

@implementation UIResponder (FirstResponder)

@dynamic currentFirstResponder ;

-(void)setYourselfToGlobalFirstResponder
{
    currentFirstResponder = self;
}

- (id)currentFirstResponder
{
    return [UIResponder currentFirstResponder];
}

+ (id)currentFirstResponder
{
    currentFirstResponder = nil;
    // 同步消息
    [[UIApplication sharedApplication] sendAction:@selector(setYourselfToGlobalFirstResponder)
                                               to:nil
                                             from:nil
                                         forEvent:nil];
    return currentFirstResponder;
}

@end