ios Changing UIScrollView scrollbar color to diffe

问题:

How can we change color of UIScrollview's scroll indicator to something like blue, green etc.

I know we can change it to white, black. But other then these colors.

Many Thanks

回答1:

Unfortunately you can't, of course you can always roll your own. These are your options:

UIScrollViewIndicatorStyleDefault:

The default style of scroll indicator, which is black with a white border. This style is good against any content background.

UIScrollViewIndicatorStyleBlack:

A style of indicator which is black and smaller than the default style. This style is good against a white content background.

UIScrollViewIndicatorStyleWhite:

A style of indicator is white and smaller than the default style. This style is good against a black content background.

回答2:

Both UIScrollView indicator are sub view of UIScrollView. So, we can access subview of UIScrollView and change the property of subview.

1 .Add UIScrollViewDelegate

@interface ViewController : UIViewController<UIScrollViewDelegate>
@end

2. Add scrollViewDidScroll in implementation section

-(void)scrollViewDidScroll:(UIScrollView *)scrollView1
{
    //get refrence of vertical indicator
    UIImageView *verticalIndicator = ((UIImageView *)[scrollView.subviews objectAtIndex:(scrollView.subviews.count-1)]);
    //set color to vertical indicator
    [verticalIndicator setBackgroundColor:[UIColor redColor]];


    //get refrence of horizontal indicator
    UIImageView *horizontalIndicator = ((UIImageView *)[scrollView.subviews objectAtIndex:(scrollView.subviews.count-2)]);
    //set color to horizontal indicator
    [horizontalIndicator setBackgroundColor:[UIColor blueColor]];
}

Note:- Because these indicator update every time when you scroll (means reset to default). SO, we put this code in scrollViewDidScroll delegate method.

Demo available on GitHub - https://github.com/ioshacks/UIScrollViewIndicatorColor

回答3:

Here's more safe Swift 3 method:

func scrollViewDidScroll(_ scrollView: UIScrollView) {
    let verticalIndicator = scrollView.subviews.last as? UIImageView
    verticalIndicator?.backgroundColor = UIColor.green
}

回答4:

Swift 2.0 :

Add UIScrollView Delegate.

func scrollViewDidScroll(scrollView: UIScrollView){
let verticalIndicator: UIImageView = (scrollView.subviews[(scrollView.subviews.count - 1)] as! UIImageView)
verticalIndicator.backgroundColor = UIColor.greenColor()

let horizontalIndicator: UIImageView = (scrollView.subviews[(scrollView.subviews.count - 2)] as! UIImageView)
horizontalIndicator.backgroundColor = UIColor.blueColor()
}

回答5:

You can change an image of indicator, but you should do this repeadeatly

func scrollViewDidScroll(_ scrollView: UIScrollView) {
    self.chageScrollIndicator()
}

func chageScrollIndicator (){
    if let indicator = self.collection.subviews.last as? UIImageView {
        let edge = UIEdgeInsets(top: 1.25,
                                left: 0,
                                bottom: 1.25,
                                right: 0)
        indicator.image = UIImage(named: "ScrollIndicator")?.withRenderingMode(.alwaysTemplate).resizableImage(withCapInsets: edge)
        indicator.tintColor = UIConfiguration.textColor
    }
}

You can use this 2 image as template:

回答6:

I wrote an article about this not so far ago. Unfortunately color of this bars defined by pre-defined images, so if you are going to change the color of bars some extra work will be required. Take a look to following link, you will definitely find an answer here since I tried to solve the same issue.

http://leonov.co/2011/04/uiscrollviews-scrollbars-customization/

回答7:

Try this it would certainly help you

    for ( UIView *view in scrollBar.subviews ) {

       if (view.tag == 0 && [view isKindOfClass:UIImageView.class])
       {
        UIImageView *imageView      = (UIImageView *)view;
        imageView.backgroundColor   = [UIColor yellowColor];
       }
    }

Explanation: UIScrollBar is a collection of subviews. Here scrollBar indicator(vertical/horizontal) is the one of the subviews and it's an UIImageView.So if we set custom color to the UIImageView it effects scrollBar Indicator.

回答8:

This is how the color of the scroll bar is changed:

    //scroll view  
    UIScrollView *scView = [[UIScrollView alloc] init];  
    scView.frame = self.view.bounds; //scroll view occupies full parent views  
    scView.contentSize = CGSizeMake(400, 800);  
    scView.backgroundColor = [UIColor lightGrayColor];  
    scView.indicatorStyle = UIScrollViewIndicatorStyleBlack;  
    scView.showsHorizontalScrollIndicator = NO;  
    scView.showsVerticalScrollIndicator = YES;  
    scView.scrollEnabled = YES;  
    [self.view addSubview: scView];

回答9:

If you wish to add image as well, here is the code for Swift 3

func scrollViewDidScroll(_ scrollView: UIScrollView) {
    let verticalIndicator = scrollView.subviews.last as? UIImageView
    verticalIndicator?.image = UIImage(named: "imageName")
}

This works for UITableView and UICollectionView as well.

回答10:

I ran into the same problem recently so I decided to write a category for it.

https://github.com/stefanceriu/UIScrollView-ScrollerAdditions

[someScrollView setVerticalScrollerTintColor:someColor]; 
[someScrollView setHorizontalScrollerTintColor:someColor];`

It blends it with the original image so only the color will change. On the other hand, it can also be modified to provide a custom image for the scrollers to use.

回答11:

Here is what I did in Swift 4, similar to previous answers. In my case I'm recoloring the image to be invisible, set correct corner radius and only execute this process once.

func scrollViewDidScroll(_ scrollView: UIScrollView) {
    let color = UIColor.red
    guard
        let verticalIndicator = scrollView.subviews.last as? UIImageView,
        verticalIndicator.backgroundColor != color,
        verticalIndicator.image?.renderingMode != .alwaysTemplate
    else { return }
    verticalIndicator.layer.masksToBounds = true
    verticalIndicator.layer.cornerRadius = verticalIndicator.frame.width / 2
    verticalIndicator.backgroundColor = color
    verticalIndicator.image = verticalIndicator.image?.withRenderingMode(.alwaysTemplate)
    verticalIndicator.tintColor = .clear
}

回答12:

please use below code on iOS Renderer

 private bool _layouted;
 public override void LayoutSubviews()
 {
       base.LayoutSubviews();
       if (!_layouted)
       {
            this.Layer.BorderColor = UIColor.Red.CGColor;
            var Verticalbar = (UIImageView)this.Subviews[this.Subviews.Length - 1];

            Verticalbar.BackgroundColor = Color.FromHex("#0099ff").ToUIColor();
            var Horizontlebar = (UIImageView)this.Subviews[this.Subviews.Length - 2];

            Horizontlebar.BackgroundColor = Color.FromHex("#0099ff").ToUIColor();
            _layouted = true;
       }
}

回答13:

You can use custom UIScrollView scrollBars to implement color in scrollbars. For more details look here