Iphone UISearchBar透明背景视图

在UISearchBar中，默认情况下应显示背景视图。如何隐藏？我只需要UISearchBar中的search textview部分。

UISearchBar背景不能通过公共方法隐藏（将透明颜色指定为

tintColor

将没有帮助）

---

如果想要精确控制文本字段的样式，应该使用UITextField。

我尝试使用遮罩层，以便使搜索栏中实际文本字段周围的所有内容都透明（从而显示下面视图中的内容）。它可以工作，但我会很紧张，在一个航运应用程序中使用它，因为你必须匹配的形状，你的面具完全的文本字段在UISearchBar的形状。如果Apple完全改变了文本字段的形状，那么你的遮罩将不合适，你将看到搜索栏渐变中你不想要的部分和/或你将看不到你想要的部分文本字段。也就是说，我是这样做的：

//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);
}

---

我伪造了图层的位置，只是想看看它是什么样子，但是你可以根据需要计算这些大小和位置。

更新：从iOS 5.0开始，如果你有背景图像，现在就可以这样做了

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

searchBar.backgroundImage = someUIImage;

（仅在iOS 6上测试，因此可能在5上被窃听！将进行检查。）

布兰登的回答不再有效（或者对我来说，无论如何也不行），所以我环顾四周，注意到：

(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>>
)

为了使它更加健壮，检查类是否是文本字段之类的子类可能是一个好主意，但除非它中断，否则我就简单了

---

编辑：按照tipycalFlow的建议，将

objectAtIndex:2

切换到

lastObject

。

Brandon的答案仍然有效，但符合Timothy Groote提到的条件。它非常简单，只需删除下面两个子视图，并确保样式设置为半透明黑色（我在IB中这样做了，但我假设在代码中这样做会起作用）

---

只是出于好奇为什么你们认为这不会得到批准？该解决方案只使用公共API。

除了Kalle的答案外，没有一个答案对我有效。 但有一些细微的改进

UITextField *sbTextField = (UITextField *)[self.mSearchBar.subviews lastObject];
[sbTextField removeFromSuperview];
[self.view addSubview:sbTextField];
CGRect sbFrame = self.mSearchBar.frame;
// Set the default height of a textfield
sbFrame.size.height = 31;   

/* 8 is the top padding for textfield inside searchbar
 * You may need to add a variable to 8 according to your requirement.
 */
sbFrame.origin.y = 8+ self.mSearchBar.superview.frame.origin.y;
sbTextField.frame = sbFrame;

[sbTextField setAutoresizingMask:UIViewAutoresizingFlexibleWidth | UIViewAutoresizingFlexibleBottomMargin];  //to support different orientations.
[self.mSearchBar removeFromSuperview];

---

+1点到卡尔。（竖起大拇指）

供未来的访客寻找答案。我发现以下内容在iOS 5+中很有效，我更喜欢它，因为它不涉及干扰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];

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

以下是我对这个问题的看法

我对织鱼也采取了类似的方法。但是，我将子视图alpha属性的设置过程封装在自己的类中

您可以将

UISearchBar

子类化，如下所示：

在UITransparentBackgroundSearchBar.h中：

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

在您的故事板中，将搜索栏类设置为UITransparentBackgroundSearchBar和voilá

---

现在，我是iOS开发新手，所以我不能说这是防弹的。如果我在另一个视图中需要相同的透明背景，它似乎可以工作，并且可以避免代码重复。

这里有一个解决方案适用于iOS 5和iOS 6。我已经检查过，没有必要更改任何其他属性（如将backgroundColor设置为

[UIColor clearColor]

）以使其正常工作

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];
    }
}

---

通过为

backgroundImage

属性设置1px*1px的透明图像，可以很容易地进行设置。 在ios 5、6上测试

searchBar.backgroundImage = [UIImage imageNamed:@"transparentImage.png"];

---

从iOS5开始，我建议使用以下方法，避免弄乱未记录的子视图。如果要子类化UISearchBarController而不是UISearchBar本身，请将

self

替换为

self.searchBar

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];

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

作为奖励：

// 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];

这里没有黑客：

if (([[[UIDevice currentDevice] systemVersion] compare:@"7.0" options:NSNumericSearch] == NSOrderedAscending)) {
    UIGraphicsBeginImageContextWithOptions(CGSizeMake(1, 1), NO, 0.0);
    UIImage *blank = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    searchBar.backgroundImage = blank;
    searchBar.backgroundColor = [UIColor clearColor];
}
else {
    searchBar.barTintColor = [UIColor clearColor];
}

---

这在与以下行一起使用时对我有效：searchBar.backgroundColor=[UIColor clearColor]；我使用的是Xcode 4.01和iOS 4.3。这对我不管用。正如上面所建议的，我也尝试过使用clearColor，但没有任何进展。我验证了4.2和4.3之间没有任何变化-如果没有其他变化消失，您可能没有正确设置IB连接。这似乎可行，但有一个奇怪的先决条件，即搜索栏样式设置为

黑色半透明

，这对我有效（iOS 6.1模拟器，Xcode 5.0.2），没有任何黑客攻击，但要小心！在iOS 7中，它会删除搜索栏本身，因此您应该在使用此黑客攻击之前检查iOS版本。如果遇到编译错误，请确保包含quartzcore框架：天哪，这很有效！边缘有点粗糙，因此kalperin，如果您有更新版本，请共享：）同时，我将尝试看看是否可以拨弄一下，使其适合我的需要。不幸的是，在视图大小发生变化时（例如从纵向到横向），附加此遮罩会阻止uisearchbar自动调整大小。对我来说不可行，但很酷@英，我没有最新消息。我仍然不想发布这样的东西（不管你的自动调整大小有多麻烦），但是图层屏蔽仍然是一个有用的工具！这很奇怪，但是删除索引2处的子视图不应该一直有效，因为数组大小显然不是固定的。更好的方法是

UITextField*sbTextField=（UITextField*）[searchBar.subviews lastObject]

Daniel：在应用商店中有一个应用程序在使用这个，正如我们所说的。有一个少得多的黑客解决方案，请检查@Coeur的回答设置

backgroundImage

是否有黑客行为，并且@Coeur的回答在iOS 7下对我也不起作用。即使

半透明

设置为

否

，条色也会被清除。如果您仍然支持iOS 4.x.+1，就像其他5个（设置图像等…）不起作用的条色一样尝试过，但这一条在iOS 6中立即起作用，这一点非常重要！有一个少得多的黑客解决方案，检查@Coeur的回答这是可行的，但我发现你必须将

搜索栏。scopeBarBackgroundImage

设置为相同的透明图像。我喜欢这个解决方案，因为它不涉及任何黑客行为。这比其他黑客更脆弱。惊人的答案。T

if (([[[UIDevice currentDevice] systemVersion] compare:@"7.0" options:NSNumericSearch] == NSOrderedAscending)) {
    UIGraphicsBeginImageContextWithOptions(CGSizeMake(1, 1), NO, 0.0);
    UIImage *blank = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    searchBar.backgroundImage = blank;
    searchBar.backgroundColor = [UIColor clearColor];
}
else {
    searchBar.barTintColor = [UIColor clearColor];
}