【代码笔记】iOS-键盘自适应弹出

一，效果图。

二，工程图。

三，代码。

ViewController.h

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController
<UITextFieldDelegate>

@end

ViewController.m

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    UITextField *field=[[UITextField alloc]initWithFrame:CGRectMake(100, 300, 50, 50)];
    field.backgroundColor=[UIColor redColor];
    field.delegate=self;
    [self.view addSubview:field];

    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
    [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];

}
#pragma -mark -keyboard notificatin
- (void)keyboardWillShow:(NSNotification *)notification {
    NSDictionary *info = [notification userInfo];
    // keyboardHeight 为键盘高度
    CGSize keyboardSize = [[info objectForKey:UIKeyboardFrameEndUserInfoKey] CGRectValue].size;
    [self animateViewWithKeyboardHeight:keyboardSize.height];
}

- (void)keyboardWillHide:(NSNotification *)notification {
    [self animateViewWithKeyboardHeight:0.0];
}

- (void)animateViewWithKeyboardHeight:(CGFloat)keyboardHeight {
    NSTimeInterval animationDuration = 0.3f;
    CGFloat height = self.view.bounds.size.height;
    CGFloat width = self.view.bounds.size.width;
    CGFloat topSize = 0.0;
    CGFloat viewH = self.view.frame.size.height-64;
    CGFloat deviceHeight = [UIScreen mainScreen].bounds.size.height;
    CGFloat animateH = deviceHeight - viewH - keyboardHeight;
    if (animateH >= 0) {
        topSize = 0;
        CGRect toRect = CGRectMake(0, topSize, width, height);
        self.view.frame = toRect;

    } else {
        topSize = animateH;
        CGRect toRect = CGRectMake(0, topSize, width, height);
        [UIView animateWithDuration:animationDuration animations:^{
            self.view.frame = toRect;
        }];
    }
}
#pragma -mark -UITextFieldDelegate
-(BOOL)textFieldShouldReturn:(UITextField *)textField
{
    [textField resignFirstResponder];

    return YES;
}

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

@end