Question

-(IBAction)nextButtonTapped:(id)sender {
    if (moreItemsgridView.contentOffset.x<=moreItemsgridView.contentSize.width) {
        CGRect frame;
        frame.origin.x = moreItemsgridView.contentOffset.x + moreItemsgridView.frame.size.width;
        frame.origin.y = 0;
        frame.size  = moreItemsgridView.frame.size;
        [moreItemsgridView scrollRectToVisible:frame animated:YES];
        //[moreItemsgridView setContentOffset:CGPointMake(moreItemsgridView.contentOffset.x + moreItemsgridView.contentSize.width, 0) animated:NO];
    }
}

-(IBAction)previousButtonTapped:(id)sender {
    if (moreItemsgridView.contentOffset.x>=moreItemsgridView.frame.size.width) {
        CGRect frame;
        frame.origin.x = moreItemsgridView.contentOffset.x - moreItemsgridView.frame.size.width;
        frame.origin.y = 0;
        frame.size = moreItemsgridView.frame.size;
        [moreItemsgridView scrollRectToVisible:frame animated:YES];
    }
}

当我点击“下一步”按钮时，我的图像可以正确滚动，但是当我单击“上一步”按钮时，它可以正确滚动，但最后只显示一半的视图...我在做什么错...请对此进行帮助。 ..

Answer 1

更新框架后，呼叫[self.view layoutIfNeeded];。

-(IBAction)nextButtonTapped:(id)sender {
    if (moreItemsgridView.contentOffset.x<=moreItemsgridView.contentSize.width) {
        CGRect frame;
        frame.origin.x = moreItemsgridView.contentOffset.x + moreItemsgridView.frame.size.width;
        frame.origin.y = 0;
        frame.size  = moreItemsgridView.frame.size;
        [moreItemsgridView scrollRectToVisible:frame animated:YES];
        //[moreItemsgridView setContentOffset:CGPointMake(moreItemsgridView.contentOffset.x + moreItemsgridView.contentSize.width, 0) animated:NO];


 [self.view layoutIfNeeded]

    }
}

-(IBAction)previousButtonTapped:(id)sender {
    if (moreItemsgridView.contentOffset.x>=moreItemsgridView.frame.size.width) {
        CGRect frame;
        frame.origin.x = moreItemsgridView.contentOffset.x - moreItemsgridView.frame.size.width;
        frame.origin.y = 0;
        frame.size = moreItemsgridView.frame.size;
        [moreItemsgridView scrollRectToVisible:frame animated:YES];


        [self.view layoutIfNeeded]
    }
}

滚动视图不能正确移动目标C中轻按“下一个”和“上一个”按钮

1 个答案: