自定义 UISearchbar 的 UITextfield - iOS

Question

我正在尝试为 UISearchbar 自定义文本字段。 下图显示了我完成了一半的工作。

我有 UISearchbar 的子类，并从我的视图控制器调用它。 我正在尝试从文本字段中删除那些深灰色线条。 下面是将 UISearchbar 添加到 viewcontroller 的子视图的实现。

searchbar = [[SearchBar alloc] initWithFrame:CGRectMake(35,78, 250, 17)];
searchbar.backgroundColor = [UIColor clearColor];
searchbar.layer.borderColor = [[UIColor clearColor] CGColor];
searchbar.layer.borderWidth = 0;

for(UIView *view in searchbar.subviews){
    if([view isKindOfClass:[UITextField class]]){
        UITextField *tf= (UITextField *)view;
        tf.layer.borderColor = [[UIColor clearColor] CGColor];
        tf.delegate = self;
        break;
    }
}
[self.view addSubview:searchbar];
searchbar.delegate = self;

UISearchBar 子类：

   - (id)initWithFrame:(CGRect)frame
  {
   self = [super initWithFrame:frame];
if (self) {
      // Initialization code
     }
     return self;
}

-(void)layoutSubviews{
     UITextField *searchField;
     [[[self subviews] objectAtIndex:0] removeFromSuperview];
     [self setTintColor:[UIColor clearColor]];
     self.clipsToBounds = YES;
     NSUInteger numViews = [self.subviews count];
     for(int i = 0; i < numViews; i++) {
        if([[self.subviews objectAtIndex:i] isKindOfClass:[UITextField class]]) { 
            searchField = [self.subviews objectAtIndex:i];
             searchField.leftViewMode = UITextFieldViewModeNever;
             searchField.backgroundColor = [UIColor clearColor];

        }


    }
    if(!(searchField == nil)) {            
        searchField.backgroundColor = [UIColor clearColor];
        searchField.textColor = [UIColor blackColor];
        searchField.frame = CGRectMake(self.frame.origin.x,self.frame.origin.y,self.frame.size.width,self.frame.size.height-10);

        [searchField setBorderStyle:UITextBorderStyleRoundedRect];

    }

    [super layoutSubviews];

}

我正在尝试实现这样的目标：文本字段不应有任何边界。 图标是扁平化的 UIImageView。

Answer 1

这是从 UISearchBar 子视图层次结构中获取文本字段并根据需要设置其属性的简单方法，例如

  UITextField *txfSearchField = [searchbar valueForKey:@"_searchField"];
[txfSearchField setBackgroundColor:[UIColor whiteColor]];
    [txfSearchField setLeftView:UITextFieldViewModeNever];
    [txfSearchField setBorderStyle:UITextBorderStyleRoundedRect];
    txfSearchField.layer.borderWidth = 8.0f; 
    txfSearchField.layer.cornerRadius = 10.0f;
        txfSearchField.layer.borderColor = [UIColor clearColor].CGColor;

Answer 2

如果您不想使用未记录的功能或使用图像，请使用以下内容：

CGSize size = CGSizeMake(30, 30);
// create context with transparent background
UIGraphicsBeginImageContextWithOptions(size, NO, 1);

// Add a clip before drawing anything, in the shape of an rounded rect
[[UIBezierPath bezierPathWithRoundedRect:CGRectMake(0,0,30,30)
                            cornerRadius:2.0] addClip];
[[UIColor whiteColor] setFill];

UIRectFill(CGRectMake(0, 0, size.width, size.height));
UIImage *image = UIGraphicsGetImageFromCurrentImageContext();
UIGraphicsEndImageContext();

[self.searchBar setSearchFieldBackgroundImage:image forState:UIControlStateNormal];

Answer 3

对于那些仍在寻找答案的人，Apple 已将searchTextField属性添加到 iOS 13 中的 UISearchBar。searchTextField 是一个继承自 UITextField 的searchTextField 。

let searchBar = UISearchBar()
var searchField : UITextField
if #available(iOS 13.0, *) {
    searchField = searchBar.searchTextField
} else {
    searchField = //One of the other methods listed
}

Answer 4

iOS 13.x 和 Swift 5.x ：

执行以下操作以访问UISearchBar中的UITextField 。

extension UISearchBar {

    /// Returns the`UITextField` that is placed inside the text field.
    var textField: UITextField {
        if #available(iOS 13, *) {
            return searchTextField
        } else {
            return self.value(forKey: "_searchField") as! UITextField
        }
    }

}

Answer 5

从 IOS-5 开始，你有外观代理，请参阅：http: //developer.apple.com/library/ios/#documentation/uikit/reference/UISearchBar_Class/Reference/Reference.html （有两个部分称为“自定义外观” "，检查两者）。

这是一个工作示例，它修改了应用程序中的所有 UISearchBars：

[[UISearchBar appearance] setSearchFieldBackgroundImage:[UIImage imageNamed:@"text_box"] forState:UIControlStateNormal];
[[UISearchBar appearance] setImage:[UIImage imageNamed:@"search_icon"] forSearchBarIcon:UISearchBarIconSearch state:UIControlStateNormal];
mysearchBar.tintColor = [UIColor whiteColor];

Answer 6

实施抗变化和高性能

对于任何阅读本文并想知道如何在 Swift 中轻松访问搜索栏的文本字段的人； 您可以使用以下代码扩展UISearchBar以添加textField属性，该代码可以抵抗底层实现更改并缓存找到的结果，因此它是高性能的。

import UIKit

private var foundTextFieldAssociationKey = UInt8()

extension UISearchBar {

  var textField: UITextField {
    get {
      let value = objc_getAssociatedObject(self, &foundTextFieldAssociationKey) as? UITextField

      if value == nil {
        let findInView = (UIView) -> UITextField? = { view in
          for subview in view.subviews {
            if let textField = (subview as? UITextField) ?? findInView(subview) {
              return textField
            }
          }
          return nil
        }

        guard let foundTextField = findInView(self) else {
          fatalError("UISearchBar doesn't seem to have a UITextField anywhere in the view hierarchy")
        }

        textField = foundTextField
        return foundTextField
      }

      return value!
    }
    set {
      objc_setAssociatedObject(self, &foundTextFieldAssociationKey, newValue, objc_AssociationPolicy.OBJC_ASSOCIATION_ASSIGN)
    }
  }

}

如果您想更改属性的名称，请确保不要将其更改为searchField 。 那会使您的搜索栏混乱。

Answer 7

现在在 iOS 13 中，您可以使用searchTextField属性直接访问文本字段。

Answer 8

我发现我需要为 iOS 10 执行此操作（从上面借用并快速适应）

extension UISearchBar {
    var textField: UITextField? {

    func findInView(_ view: UIView) -> UITextField? {
        for subview in view.subviews {
            print("checking \(subview)")
            if let textField = subview as? UITextField {
                return textField
            }
            else if let v = findInView(subview) {
                return v
            }
        }
        return nil
      }

      return findInView(self)
    }
 }  

Answer 9

简短

extension UISearchBar {
    var textField:UITextField {
        guard let txtField = self.value(forKey: "_searchField") as? UITextField else {
            assertionFailure()
            return UITextField()
        }
        return txtField
    }
}