ScrollView 改变按钮 backgroundImage 时跳转到页面顶部

ScrollView jumps to the top of the page when change button backgroundImage

当我点击页面底部的按钮时,ScrollView 会跳转到页面顶部。当我总是点击页面底部的 uitexfield 时,也会发生这种情况。我该怎么做才能让它静止不动? 在 viewDidLoad():

self.scrollView.pagingEnabled=NO;

在 iewDidLayoutSubviews:

  -(void)viewDidLayoutSubviews{
       [super viewDidLayoutSubviews];

   self.scrollView.frame=CGRectMake(0, 0, SCREEN_WIDTH, SCREEN_HEIGHT);
   self.scrollView.contentSize = CGSizeMake(SCREEN_WIDTH, 1150);


 }

问题是在更改此处按钮的 ImageBackground 时:

 - (IBAction)pressedData:(id)sender {


   if ( !self.checkDataIsPressed ) {
        self.checkData =true;
        [self.checkDataPerson setBackgroundImage:
        [UIImage imageNamed:@"check_on"]forState:UIControlStateNormal]; //the jumps scrollview is here
   }else{
        self.checkData =false;
       [self.checkDataPerson setBackgroundImage:
       [UIImage imageNamed:@"check_off"]forState:UIControlStateNormal]; //the jumps scrollview is here
    }

}

点击按钮

[scrollView setContentOffset:CGPointMake(320,0) animated:YES];