//
//  TPKeyboardController.m
//  ThePaperDemo
//
//  Created by scar1900 on 14/12/4.
//  Copyright (c) 2014年 scar1900. All rights reserved.
//

#import "TPKeyboardController.h"

@interface TPKeyboardController ()
@end

@implementation TPKeyboardController
@synthesize responderHeight,keyboardOffset;

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view.
    UITapGestureRecognizer *tapGesture = [[UITapGestureRecognizer alloc]initWithTarget:self action:@selector(tap:)];
    [self.keyboardView addGestureRecognizer:tapGesture];
    
    [self.view addSubview:self.keyboardView];
    
    //增加监听，当键盘出现或改变时收出消息
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillShow:)
                                                 name:UIKeyboardWillShowNotification
                                               object:nil];
    
    //增加监听，当键退出时收出消息
    [[NSNotificationCenter defaultCenter] addObserver:self
                                             selector:@selector(keyboardWillHide:)
                                                 name:UIKeyboardWillHideNotification
                                               object:nil];
}


- (UIScrollView *)keyboardView {
    if (!_keyboardView) {
        _keyboardView = [[UIScrollView alloc]initWithFrame:self.view.bounds];
        _keyboardView.scrollEnabled = NO;
        _keyboardView.backgroundColor = [UIColor clearColor];
        _keyboardView.showsVerticalScrollIndicator = NO;
        _keyboardView.showsHorizontalScrollIndicator = NO;
        _keyboardView.autoresizingMask = AutoresizingFull;
    }
    return _keyboardView;
}

/**
 *  触摸隐藏键盘
 *
 *  @param sender 触摸手势
 */
- (void)tap:(UITapGestureRecognizer*)sender {
    [self closeKeyBoard];
}

#pragma mark - keyBoard event
- (void)closeKeyBoard {
    [[UIApplication sharedApplication] sendAction:@selector(resignFirstResponder) to:nil from:nil forEvent:nil];
}

//当键盘出现或改变时调用
- (void)keyboardWillShow:(NSNotification *)aNotification
{
    //获取键盘的高度
    NSDictionary *userInfo = [aNotification userInfo];
    NSValue *aValue = [userInfo objectForKey:UIKeyboardFrameEndUserInfoKey];
    CGRect keyboardRect = [aValue CGRectValue];
    CGFloat keyboardHeight  = keyboardRect.size.height;
    
    if (responderHeight>(CGRectGetHeight(self.keyboardView.frame)-keyboardHeight)) {
        keyboardOffset = responderHeight- (CGRectGetHeight(self.keyboardView.frame)-keyboardHeight);
        [self.keyboardView setContentOffset:CGPointMake(0, keyboardOffset)];
        self.keyboardView.scrollEnabled = YES;
    }
}

//当键退出时调用
- (void)keyboardWillHide:(NSNotification *)aNotification
{
    CGPoint currentOffset = self.keyboardView.contentOffset;
    currentOffset.y = currentOffset.y - keyboardOffset;
    [self.keyboardView setContentOffset:currentOffset];
    keyboardOffset = 0;
}


#pragma mark - textField Delegate
- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField {
    CGRect textRect = textField.frame;
    responderHeight = textRect.origin.y+textRect.size.height;
    return YES;
}

- (BOOL)textFieldShouldReturn:(UITextField *)textField {
    [self closeKeyBoard];
    return YES;
}

- (void)dealloc  {
    //增加监听，当键盘出现或改变时收出消息
    [[NSNotificationCenter defaultCenter] removeObserver:self
                                                    name:UIKeyboardWillShowNotification
                                                  object:nil];
    
    //增加监听，当键退出时收出消息
    [[NSNotificationCenter defaultCenter] removeObserver:self
                                                 name:UIKeyboardWillHideNotification
                                               object:nil];
}

- (void)didReceiveMemoryWarning {
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

@end