如何从 UIScrollView 获取 UIButton 位置

Question

我有一个 scrollView，上面有很多按钮。我试图从滚动中获取按钮位置，以便我可以将其滚动到该位置。我的问题是，单击每个按钮后，我总是在 _btnV.frame.origin.x 中获得相同的值。那么请问我该如何解决这个问题？

- (void)scrollView{

    segmentWidth = screenWidth / 5;

    NSArray *images = @[@"Smiley-1.png",@"Smiley-2.png",@"Smiley-3.png",@"Smiley-4.png",@"Smiley-5.png",@"Smiley-5.png",@"Smiley-5.png",@"Smiley-4.png",@"Smiley-1.png",@"Smiley-2.png",@"Smiley-3.png",@"Smiley-4.png"];

    long ScrollContentSize = ((images.count -1)*segmentWidth)+screenWidth;

    _scrlView.contentSize = CGSizeMake(ScrollContentSize, _scrlView.frame.size.height);

    float screenX2 = screenHeight/2 - segmentWidth/2;

    __block float screenX = (screenWidth-segmentWidth)/2;

    NSMutableArray *arr = [[NSMutableArray alloc] init];

    for(int i=0; i<images.count; i++)
    {
        _btnV = [[UIButton alloc]init];
        [_btnV setFrame:CGRectMake(screenX, screenX2, segmentWidth, segmentWidth)];
        [_btnV setImage:[UIImage imageNamed:[NSString stringWithFormat:@"%@",[images objectAtIndex:i]]] forState:UIControlStateNormal];
        [_btnV setBackgroundColor:[UIColor redColor]];
        [_btnV addTarget:self action:@selector(scrollToMe:) forControlEvents:UIControlEventTouchUpInside];

        [_btnV setTag:i];

        [arr addObject:_btnV];
        [_scrlView addSubview:_btnV];

        screenX = screenX+segmentWidth;
    }

    _menuItems = arr;

    [self.view addSubview:_scrlView];
}


-(void) scrollToMe:(id)sender{

    int scrollX = _scrlView.contentOffset.x;
    int mod = scrollX % segmentWidth;
    int position = scrollX/segmentWidth;
    float positionOffset = (float) mod / segmentWidth;

    scrollX = position * segmentWidth;

    NSLog(@"position:%f",_btnV.frame.origin.x);

    //scrollX = ...

    [_scrlView setContentOffset:CGPointMake(scrollX, scrollX) animated:YES];
}

Answer 1

使用标签值查找按钮

-(void) scrollTo:(id)sender{

    UIButton * button = (UIButton *)sender;
    int position = button.tag;

    scrollX = position * segmentWidth;

    NSLog(@"position:%f",_btnV.frame.origin.x);

    //scrollX = ...

    [_scrlView setContentOffset:CGPointMake(scrollX, scrollX) animated:YES];
}

Answer 2

您正在调用 UIButton 的选择器方法。所以在这个方法中，你可以直接得到UIButton相对于UIScrollView的位置。喜欢

-(void) scrollTo:(id)sender{

    UIButton* btnClick = (UIButton*)sender;
    NSLog(@"X position : %f",btnClick.frame.origin.x);
}

希望对您有所帮助。

Answer 3

试试这个，它会正确记录所有按钮的位置

 -(void) scrollTo:(id)sender{

    int scrollX = _scrlView.contentOffset.x;
    int mod = scrollX % segmentWidth;
    int position = scrollX/segmentWidth;
    float positionOffset = (float) mod / segmentWidth;

    scrollX = position * segmentWidth;
for(int i=0; i<images.count; i++)
{   if([[[_scrlView subviews] objectAtIndex:i] isKindOfClass:[UIButton class]]) {
        Button btn = [[_scrlView subviews] objectAtIndex:i];
NSLog(@"position:%f",btn.frame.origin.x);
    }

}
    //scrollX = ...

    [_scrlView setContentOffset:CGPointMake(scrollX, scrollX) animated:YES];
}

如何从 UIScrollView 获取 UIButton 位置

How to get UIButton position from UIScrollView

objective-c

uibutton

uiscrollview

ios