如何沿y轴向下移动按钮动作iPhone

Question

i have a button acton with outlet btnAdd, when it pressed it add text field, i want to move button action also below textfields and same want to recover back when button BtnRemove pressed,

 - (IBAction)btnAddTxtField:(id)sender {

    textField = [[UITextField alloc] initWithFrame:CGRectMake(76, ([txtFieldArray count] * 30), 191, 25)];
    [textField setBorderStyle:UITextBorderStyleLine];
    textField.font = [UIFont systemFontOfSize:20];
    textField.placeholder = @"Enter text";
    textField.autocorrectionType = UITextAutocorrectionTypeNo;
    textField.keyboardType = UIKeyboardTypeDefault;
    textField.returnKeyType = UIReturnKeyDone;
    textField.clearButtonMode = UITextFieldViewModeWhileEditing;
    textField.contentVerticalAlignment = UIControlContentVerticalAlignmentCenter;
    textField.delegate = self;
    [myScrollview addSubview:textField];
    [txtFieldArray addObject:textField];


    CGRect frame = bottomView.frame;
    frame.origin.y += textField.frame.size.height + 5;

    btnAdd = [[UIButton alloc] initWithFrame:CGRectMake(210, ([txtFieldArray count] *30), 20, 20)];
   frame.origin.y += btnAdd.frame.size.height +5;
    bottomView.frame = frame;
    textField.hidden = NO;

}

Answer 1

Once you have modified the frame variable, set it to the button in an animation block:

 [UIView animateWithDuration:0.2 animations:^{
     [btnAdd setFrame:frame];
 } 
 completion:^(BOOL finished){
      //Do something on completion if you want
 }];

Obviously you can change the animation duration (0.2) to anything that you would like. To reverse it, do the same, set the origin.y of the frame CGRect, and set it to the button in the animation block above.

Answer 2

[UIView animateWithDuration: delay: options: animations: completion:];

Would be your choice. You can check the documentation here .