【代码笔记】iOS-键盘自适应弹出

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController
<UITextFieldDelegate>

@end

#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