【代码笔记】iOS-屏幕根据键盘自动的变化高度

一，效果图。

二，代码。

ViewController.h

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController
<UITextFieldDelegate>

@end

ViewController.m

#import "ViewController.h"

#define  W [UIScreen mainScreen].bounds.size.width
#define  H [UIScreen mainScreen].bounds.size.height

@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];
}

#pragma -mark -UITextFieldDelegate
-(BOOL)textFieldShouldReturn:(UITextField *)textField
{
    [textField resignFirstResponder];

    //self.view 恢复原位
    NSTimeInterval animationDuration=0.10f;
    [UIView beginAnimations:@"ResizeForKeyboard" context:nil];
    [UIView setAnimationDuration:animationDuration];
    float width = W;
    float height = H;
    float Y = 0.0f;
    CGRect rect=CGRectMake(0.0f,Y,width,height);
    self.view.frame=rect;
    [UIView commitAnimations];

    return YES;
}

-(BOOL)textFieldShouldBeginEditing:(UITextField *)textField
{
    NSTimeInterval animationDuration=0.30f;
    [UIView beginAnimations:@"ResizeForKeyboard" context:nil];
    [UIView setAnimationDuration:animationDuration];
    float width = W;
    float height = H;
    //上移100个单位，按实际情况设置
    CGRect rect=CGRectMake(0.0f,-100,width,height);
    self.view.frame=rect;
    [UIView commitAnimations];

    return YES;
}

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

@end