【代码笔记】iOS-屏幕根据键盘自动的变化高度

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController
<UITextFieldDelegate>

@end

#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