Question

    for subView in searchBar.subviews {
        if let scopeBar = subView as? UISegmentedControl {
            scopeBar.backgroundColor = UIColor.blueColor()
        }
    }

我一直在尝试上面的代码尝试获取对scopeBar的引用，然后设置其背景颜色，但我无法获得引用。它似乎只经历了一次循环，暗示搜索栏只有一个子视图。在调试器中，搜索栏似乎有一个名为_scopeBar的实例变量，其类型为（UISegmentedControl *）。

    if let topView = searchBar.subviews.first {
        for subView in topView.subviews {
            if let cancelButton = subView as? UIButton {
                cancelButton.tintColor = UIColor.whiteColor()
                cancelButton.enabled = true
            }
        }
    }

第二个代码块用于访问搜索栏的cancelButton。

Answer 1

您可以将scopeBar背景图像设置为纯色图像。

首先，您需要create an UIImage from a color。为此，您可以创建一个函数或extension on the UIImage，例如以下代码：

Swift 3

import UIKit

extension UIImage {
    class func imageWithColor(color: UIColor) -> UIImage {
        let rect: CGRect = CGRect(x: 0, y: 0, width: 1, height: 1)
        UIGraphicsBeginImageContextWithOptions(CGSize(width: 1, height: 1), false, 0)
        color.setFill()
        UIRectFill(rect)
        let image: UIImage = UIGraphicsGetImageFromCurrentImageContext()!
        UIGraphicsEndImageContext()
        return image
    }
}

之后，您只需在范围栏上设置backgroundImage：

Swift 3

// Set the scopeBar's background color:
searchBar.scopeBarBackgroundImage = UIImage.imageWithColor(color: UIColor.blue)

Answer 2

我有一个示例问题，我解决了以下代码。

CGSize imageSize = CGSizeMake(64, 64);
UIColor *fillColor = [UIColor colorWithRed:228/255.0 green:228/255.0 blue:228/255.0 alpha:1.0];
UIGraphicsBeginImageContextWithOptions(imageSize, YES, 0);
CGContextRef context = UIGraphicsGetCurrentContext();
[fillColor setFill];
CGContextFillRect(context, CGRectMake(0, 0, imageSize.width, imageSize.height));
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

self.searchController.searchBar.scopeBarBackgroundImage = image;

Answer 3

- (void)changeScopeBarColor {
NSMutableArray<UIView*> *views = [NSMutableArray new];
NSArray<UIView *> *subviews = [_searchBar subviews];
[views addObjectsFromArray:subviews];
for (;;) {
    if (views.count == 0) {
        break;
    }

    UIView *v = [views firstObject];
    [views removeObject:v];

    if ([[[v class] description] isEqualToString:@"_UISearchBarScopeBarBackground"]) {
        v.backgroundColor = [UIColor whiteColor];
        break;
    }
    if (v.subviews.count > 0)
        [views addObjectsFromArray:v.subviews];
    }
}

UISearchBar范围栏背景图片可设置，但不是它的颜色？

3 个答案: