[[searchBar.subviews objectAtIndex:0] removeFromSuperview];

这里有一项解决办法是iOS 5和iOS 6。 我已经核实,没有必要改变任何其他财产(如将背景分类为<编码>[统一分类]),使之发挥作用。

for (UIView * v in searchBar.subviews) {
    if ([v isKindOfClass:NSClassFromString(@"UISearchBarTextField")]) {
        v.superview.alpha = 0;
        UIView *containerView = [[UIView alloc] initWithFrame:searchBar.frame];
        [containerView addSubview:v];
        [self.view addSubview:containerView];
    }
}

从5开始,我建议采取下列做法,避免用undocumented subviews. 将“UISearch BarController”改为“UISearch BarController”。

// transparency for UISearchBar
self.translucent = YES;
self.backgroundImage = [UIImage new];
self.scopeBarBackgroundImage = [UIImage new];

作为奖金:

// transparency for UIToolbar
self.translucent = YES;
[self setBackgroundImage:[UIImage new] forToolbarPosition:UIToolbarPositionAny barMetrics:UIBarMetricsDefault];
[self setShadowImage:[UIImage new] forToolbarPosition:UIToolbarPositionAny];

// transparency for UINavigationBar
self.translucent = YES;
[self setBackgroundImage:[UIImage new] forBarMetrics:UIBarMetricsDefault];
self.shadowImage = [UIImage new];

// transparency for UITabBar
self.backgroundImage = [UIImage new];
self.shadowImage = [UIImage new];

最新信息:根据SOS5.0,如果你有背景形象,你现在可以这样做。

searchBar.backgroundImage = someUIImage;

(只有经过6号SOS测试,所以可能gged5条!) 检查。

Brandon的回答不再奏效(或对我来说,不管怎么说),因此,我看一线,并指出:

(gdb) po [searchBar subviews]
<__NSArrayM 0x665ab80>(
<UISegmentedControl: 0x63aad80; frame = (0 0; 225 44); opaque = NO; layer = <CALayer: 0x6368420>>,
<UISearchBarBackground: 0x6347280; frame = (0 0; 225 44); layer = <CALayer: 0x638a230>>,
<UISearchBarTextField: 0x6331110; frame = (0 0; 0 0); clipsToBounds = YES; opaque = NO; layer = <CALayer: 0x63a20f0>>
)

我认为,第3条是习惯案文领域,大概是我所希望的,但从表面上删除第0和第1号分则,却不足以解决问题。 我在结束发言之前有以下几个方面:does work:

UITextField *sbTextField = (UITextField *)[searchBar.subviews lastObject];
[sbTextField removeFromSuperview];
[self.view addSubview:sbTextField];
sbTextField.frame = searchBar.frame;
[searchBar removeFromSuperview];

为使这一比喻更加有力,也许会有一个好的想法,即检查这一类别是案文领域的一个子类别,但除非它打破一米,而仅仅留下简单。

Edit:changeed objectAtIndex:2 to lastObject as tipycalFlow.

今后参观者寻求答案。 我发现,以下措施在5+中是有效的,因此更喜欢它,因为它没有涉及UISearchBar本身的布局。

UISearchBar * search = [[UISearchBar alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, 44)];
[search setBackgroundColor:[UIColor clearColor]];
[search setPlaceholder:@"Search"];

for (UIView * v in [search subviews]) {
    if (![v isKindOfClass:[UITextField class]]) {
        v.alpha = 0;
    }
}

[header addSubview:search];
[search release];

UISearch Bar背景不能被公用方法所掩盖(在tintColor上签名的有透明度的颜色。

您应使用UIText 如果你想要准确控制案文的实地风格,则需要实地。

我尝试使用面罩层,以便使搜索栏中实际案文领域的所有内容具有透明度(从下面的角度来看显示内容)。 由于你必须把你面罩的形形形同乌斯敦巴拉的文字场面相匹配,因此,它可以做些什么,但又会很疲软。 如果 Apple果完全改变案文领域的形式,那么你的面罩就能够打上灯,而你看看看着你不想要的那部分探条线梯度,和(或)你 won不见你想要的文字部分。 这就是说:

//first make sure you include core animation so that the compiler will know about your view s layer
#import <QuartzCore/QuartzCore.h>

//now make a mask.  this is basically just a solid colored shape.  When you apply the mask, anywhere where the color is solid will become transparent in your view.  i used the excellent Opacity (http://likethought.com/opacity/) to generate this code, but you can do it any way you d like

@interface SearchMaskLayer : CALayer {
}
@end

@implementation SearchMaskLayer

- (void)drawInContext:(CGContextRef)context
{


    CGRect imageBounds = CGRectMake(0, 0, 310, 34);
    CGRect bounds = imageBounds;

    CGFloat alignStroke;
    CGFloat resolution;
    CGMutablePathRef path;
    CGPoint point;
    CGPoint controlPoint1;
    CGPoint controlPoint2;
    UIColor *color;
    resolution = 0.5 * (bounds.size.width / imageBounds.size.width + bounds.size.height / imageBounds.size.height);

    CGContextSaveGState(context);
    CGContextTranslateCTM(context, bounds.origin.x, bounds.origin.y);
    CGContextScaleCTM(context, (bounds.size.width / imageBounds.size.width), (bounds.size.height / imageBounds.size.height));

    // Layer 1

    alignStroke = 0.0;
    path = CGPathCreateMutable();
    point = CGPointMake(295.0, 32.0);
    point.x = (round(resolution * point.x + alignStroke) - alignStroke) / resolution;
    point.y = (round(resolution * point.y + alignStroke) - alignStroke) / resolution;
    CGPathMoveToPoint(path, NULL, point.x, point.y);
    point = CGPointMake(310.0, 17.0);
    point.x = (round(resolution * point.x + alignStroke) - alignStroke) / resolution;
    point.y = (round(resolution * point.y + alignStroke) - alignStroke) / resolution;
    controlPoint1 = CGPointMake(303.229, 32.0);
    controlPoint1.x = (round(resolution * controlPoint1.x + alignStroke) - alignStroke) / resolution;
    controlPoint1.y = (round(resolution * controlPoint1.y + alignStroke) - alignStroke) / resolution;
    controlPoint2 = CGPointMake(310.0, 25.229);
    controlPoint2.x = (round(resolution * controlPoint2.x + alignStroke) - alignStroke) / resolution;
    controlPoint2.y = (round(resolution * controlPoint2.y + alignStroke) - alignStroke) / resolution;
    CGPathAddCurveToPoint(path, NULL, controlPoint1.x, controlPoint1.y, controlPoint2.x, controlPoint2.y, point.x, point.y);
    point = CGPointMake(310.0, 17.0);
    point.x = (round(resolution * point.x + alignStroke) - alignStroke) / resolution;
    point.y = (round(resolution * point.y + alignStroke) - alignStroke) / resolution;
    CGPathAddLineToPoint(path, NULL, point.x, point.y);
    point = CGPointMake(295.0, 2.0);
    point.x = (round(resolution * point.x + alignStroke) - alignStroke) / resolution;
    point.y = (round(resolution * point.y + alignStroke) - alignStroke) / resolution;
    controlPoint1 = CGPointMake(310.0, 8.771);
    controlPoint1.x = (round(resolution * controlPoint1.x + alignStroke) - alignStroke) / resolution;
    controlPoint1.y = (round(resolution * controlPoint1.y + alignStroke) - alignStroke) / resolution;
    controlPoint2 = CGPointMake(303.229, 2.0);
    controlPoint2.x = (round(resolution * controlPoint2.x + alignStroke) - alignStroke) / resolution;
    controlPoint2.y = (round(resolution * controlPoint2.y + alignStroke) - alignStroke) / resolution;
    CGPathAddCurveToPoint(path, NULL, controlPoint1.x, controlPoint1.y, controlPoint2.x, controlPoint2.y, point.x, point.y);
    point = CGPointMake(15.0, 2.0);
    point.x = (round(resolution * point.x + alignStroke) - alignStroke) / resolution;
    point.y = (round(resolution * point.y + alignStroke) - alignStroke) / resolution;
    CGPathAddLineToPoint(path, NULL, point.x, point.y);
    point = CGPointMake(0.0, 17.0);
    point.x = (round(resolution * point.x + alignStroke) - alignStroke) / resolution;
    point.y = (round(resolution * point.y + alignStroke) - alignStroke) / resolution;
    controlPoint1 = CGPointMake(6.771, 2.0);
    controlPoint1.x = (round(resolution * controlPoint1.x + alignStroke) - alignStroke) / resolution;
    controlPoint1.y = (round(resolution * controlPoint1.y + alignStroke) - alignStroke) / resolution;
    controlPoint2 = CGPointMake(0.0, 8.771);
    controlPoint2.x = (round(resolution * controlPoint2.x + alignStroke) - alignStroke) / resolution;
    controlPoint2.y = (round(resolution * controlPoint2.y + alignStroke) - alignStroke) / resolution;
    CGPathAddCurveToPoint(path, NULL, controlPoint1.x, controlPoint1.y, controlPoint2.x, controlPoint2.y, point.x, point.y);
    point = CGPointMake(0.0, 17.0);
    point.x = (round(resolution * point.x + alignStroke) - alignStroke) / resolution;
    point.y = (round(resolution * point.y + alignStroke) - alignStroke) / resolution;
    CGPathAddLineToPoint(path, NULL, point.x, point.y);
    point = CGPointMake(15.0, 32.0);
    point.x = (round(resolution * point.x + alignStroke) - alignStroke) / resolution;
    point.y = (round(resolution * point.y + alignStroke) - alignStroke) / resolution;
    controlPoint1 = CGPointMake(0.0, 25.229);
    controlPoint1.x = (round(resolution * controlPoint1.x + alignStroke) - alignStroke) / resolution;
    controlPoint1.y = (round(resolution * controlPoint1.y + alignStroke) - alignStroke) / resolution;
    controlPoint2 = CGPointMake(6.771, 32.0);
    controlPoint2.x = (round(resolution * controlPoint2.x + alignStroke) - alignStroke) / resolution;
    controlPoint2.y = (round(resolution * controlPoint2.y + alignStroke) - alignStroke) / resolution;
    CGPathAddCurveToPoint(path, NULL, controlPoint1.x, controlPoint1.y, controlPoint2.x, controlPoint2.y, point.x, point.y);
    point = CGPointMake(295.0, 32.0);
    point.x = (round(resolution * point.x + alignStroke) - alignStroke) / resolution;
    point.y = (round(resolution * point.y + alignStroke) - alignStroke) / resolution;
    CGPathAddLineToPoint(path, NULL, point.x, point.y);
    CGPathCloseSubpath(path);
    color = [UIColor colorWithRed:0.0 green:0.0 blue:0.0 alpha:1.0];
    [color setFill];
    CGContextAddPath(context, path);
    CGContextFillPath(context);
    CGPathRelease(path);
}

后来,在你的一种方法中,使用面罩。

- (void)viewDidLoad {
    [super viewDidLoad];
    SearchMaskLayer *maskLayer = [[SearchMaskLayer alloc] init];
    [maskLayer setFrame:CGRectMake(0, 0, 310, 34)];
    [maskLayer setPosition:CGPointMake(162,21)];
    [maskLayer setNeedsDisplay];    
    [self.searchBar.layer setNeedsDisplay];
    [self.searchBar.layer setMask:maskLayer];
    [maskLayer release];
}

我认为,这个层的位置只是看它想要看什么,但你可以计算这些大小和位置,以满足你们的需要。

这里是我的。

#import <UIKit/UIKit.h>
@interface UITransparentBackgroundSearchBar : UISearchBar
@end

#import "UITransparentBackgroundSearchBar.h"
@implementation UITransparentBackgroundSearchBar

-(void)didAddSubview:(UIView *)subview {
    if (![subview isKindOfClass:[UITextField class]]) {
        subview.alpha = 0;
    }
}

@end