Instance code in IOS that only allows textfield to use keyboard notification

Time:2022-5-10

code:

#import "ViewController.h"
@interface ViewController ()
@end
@implementation ViewController
- (void)viewDidLoad {
  [super viewDidLoad];
  // Do any additional setup after loading the view, typically from a nib.
  //Adding keyboard events to textfield
  [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(addKeyboardNoti) name:UITextFieldTextDidBeginEditingNotification object:nil];
  [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(removeKeyboardNoti) name:UITextFieldTextDidEndEditingNotification object:nil];
}
#pragma -mark -keyboard notificatin
//Keyboard events
- (void)keyboardWillShow:(NSNotification *)notification {
  NSDictionary *info = [notification userInfo];
  //Keyboardheight is the height of the keyboard
  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 -UITextFieldText Notification
//Add keyboard event
-(void)addKeyboardNoti
{
  NSLog(@"------addKeyboardNoti-------");
  [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillShow:) name:UIKeyboardWillShowNotification object:nil];
  [[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(keyboardWillHide:) name:UIKeyboardWillHideNotification object:nil];
}
//Remove keyboard event
-(void)removeKeyboardNoti
{
  NSLog(@"------removeKeyboardNoti---------");
  [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillShowNotification object:nil];
  [[NSNotificationCenter defaultCenter] removeObserver:self name:UIKeyboardWillHideNotification object:nil];
}
- (void)didReceiveMemoryWarning {
  [super didReceiveMemoryWarning];
  // Dispose of any resources that can be recreated.
}
@end

summary

The above is the example code introduced by Xiaobian to you that only textfield uses keyboard notification in IOS. I hope it will be helpful to you. If you have any questions, please leave me a message and Xiaobian will reply to you in time. Thank you very much for your support to the developeppaer website!

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