将 UIimageView 放在前面

Posted 2023-03-11

【中文标题】将 UIimageView 放在前面

【英文标题】：Bring UIimageView to front

【发布时间】：2015-10-01 07:36:29

【问题描述】：

我有一个 ViewController，其中有一个 UIScrollView。在那我有一个 UIView 和 UIView 我必须添加标签和图像。图片应该在我的标签上方。

顺序为 Controller>>ScrollView>>UIView >> UILabel >> UIImageView

但我无法将 UIimageView 添加到视图中。

这是我的代码

 scrollView =[[UIScrollView alloc]init];
[scrollView setFrame:CGRectMake(0, 0, 320, 480)];
 [scrollView setContentSize:CGSizeMake(320,2820)];
[scrollView setBackgroundColor:[UIColor groupTableViewBackgroundColor]];
[scrollView setScrollEnabled:YES];
[scrollView setShowsHorizontalScrollIndicator:YES];
[scrollView setShowsVerticalScrollIndicator:NO];
[self.view addSubview:scrollView];


    UIView *firstView = [[UIView alloc]initWithFrame:CGRectMake(5, 5, 310, 300)];
firstView.backgroundColor = [UIColor whiteColor];
[scrollView addSubview:firstView];


UILabel *label =[[UILabel alloc]initWithFrame:CGRectMake(65, 3, 180, 50)];
label.text = @"ABC";
label.textAlignment =NSTextAlignmentCenter;
label.textColor = [UIColor colorWithRed:74.0/255.0 green:144.0/255.0 blue:226.0/255.0 alpha:1];
label.font=[UIFont fontWithName:@"Helvetica-Bold" size:18];
[firstView addSubview:label];

 imgView = [[UIImageView alloc]initWithFrame:CGRectMake(115, 0, 90, 90)];
imgView.image = [UIImage imageNamed:@"thumbs4.png"];
[self.view bringSubviewToFront:imgView];

[self.view bringSubviewToFront:imgView] 这行什么都不做

【问题讨论】：

试试：[scrollView addSubview:imgView];

@TusharJ。 - 是的，它在添加到滚动视图后出现，但我希望它的框架是固定的。因为我不希望它被滚动

在我看来，理想的方法是将imgView 添加到self.view 并使scrollView 透明。但我认为，您正在为scrollView [scrollView setBackgroundColor:[UIColor groupTableViewBackgroundColor]]; 提供背景颜色。试试这个：[self.view addSubview:imgView]; [self.view bringSubviewToFront:imgView];

要将超级视图的子视图放在前面，首先必须将其添加到超级视图中。

@TusharJ。 - 谢谢好友

【参考方案1】：

UIScrollView *scrollView =[[UIScrollView alloc]init];
[scrollView setFrame:CGRectMake(0, 0, 320, 480)];
[scrollView setContentSize:CGSizeMake(320,2820)];
[scrollView setBackgroundColor:[UIColor groupTableViewBackgroundColor]];
[scrollView setScrollEnabled:YES];
[scrollView setShowsHorizontalScrollIndicator:YES];
[scrollView setShowsVerticalScrollIndicator:NO];
[self.view addSubview:scrollView];

UIImageView *imgView = [[UIImageView alloc]initWithFrame:CGRectMake(115, 0, 90, 90)];
imgView.image = [UIImage imageNamed:@"dream.jpg"];
[self.view addSubview:imgView];

UIView *firstView = [[UIView alloc]initWithFrame:CGRectMake(5, 5, 310, 300)];
firstView.backgroundColor = [UIColor blueColor];
[scrollView addSubview:firstView];


UILabel *label =[[UILabel alloc]initWithFrame:CGRectMake(65, 3, 180, 50)];
label.text = @"ABC";
label.textAlignment =NSTextAlignmentCenter;
label.textColor = [UIColor colorWithRed:74.0/255.0 green:144.0/255.0 blue:226.0/255.0 alpha:1];
label.font=[UIFont fontWithName:@"Helvetica-Bold" size:18];
[firstView addSubview:label];

我得到了类似的输出

【讨论】：

是的，谢谢@Anbu.Karthik

【参考方案2】：

您应该在操作之前将图像视图添加到 self.view。但如果它是最后添加的子视图，则不必将其置于最前面。

imgView = [[UIImageView alloc]initWithFrame:CGRectMake(115, 0, 90, 90)];
imgView.image = [UIImage imageNamed:@"thumbs4.png"];
[self.view addSubview:imgView] // added as subview
[self.view bringSubviewToFront:imgView]; // not really needed. imgView is actually in front