iOS dynamically gets the keyboard height and changes the position of the dialog box

nsnotificationcenter: notification when the keyboard appears and disappears

uikeyboardwillshownotification; uikeyboarddidshownotification; uikeyboardwillhidenotification; uikeyboarddidhidenotification;

receive notification of keyboard events in the view controller that you want to use the keyboard (both in viewdidload):

-(void) registerforkeyboardnotifications
{

When the keyboard changes, it calls
[[Nsnotificationcenter Defaultcenter] addobserver:self selector: @selector (keyboardwasshown:) Name: Uikeyboardwillchangeframenotification Object:nil];

The keyboard is closed to call
[[Nsnotificationcenter Defaultcenter] addobserver:self selector: @selector (keyboardwashidden:) Name: Uikeyboarddidhidenotification Object:nil];

}

-(void) Keyboardwasshown: (nsnotification *) Notif
{
    nsdictionary *info = [Notif userInfo];
    
    nsvalue *value = [info objectforkey:uikeyboardframeenduserinfokey];
    
    cgsize keyboardsize = [value cgrectvalue].size;
   
    _namefield.frame=cgrectmake (5, self.view.frame.size.height-keyboardsize.height-30, 155, 30);
    _sexfield.frame=cgrectmake (self.view.frame.size.height-keyboardsize.height-30, 155, 30 );
}

-(void) Keyboardwashidden: (nsnotification *) Notif
{
    nsdictionary *info = [Notif UserInfo];
    
    nsvalue *value = [info objectforkey:uikeyboardframebeginuserinfokey];
    
    cgsize keyboardsize = [value cgrectvalue].size;
    
    NSLog (@ "Keyboardwashidden keyboard:%f", keyboardsize.height);
    
   //Keyboardwasshown = NO;
    _namefield.frame=cgrectmake (5, 269, 155, 30);
    _sexfield.frame=cgrectmake (160, 269, 155, 30);
}