iOS中的UISearchBar搜索框组件基础使用指南

#import <UIKit/UIKit.h>

@interface LSSearchBar : UISearchBar

@end

#import "LSSearchBar.h"

@implementation LSSearchBar

- (void)layoutSubviews {

    [super layoutSubviews];

    //通过遍历self.subviews找到searchField
    UITextField *searchField;
    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];
        }
    }

    //如果上述方法找不到searchField，那就试试下面的方法吧

    if (searchField ==  nil) {
        NSArray *arraySub = [self subviews];
        UIView *viewSelf = [arraySub objectAtIndex:0];
        NSArray *arrayView = [viewSelf subviews];
        for(int i = 0; i < arrayView.count; i++) {
            if([[arrayView objectAtIndex:i] isKindOfClass:[UITextField class]]) {
                searchField = [arrayView objectAtIndex:i];
            }
        }
    }

    if(!(searchField == nil)) {
        //设置颜色
        searchField.textColor = [UIColor whiteColor];

        //设置背景颜色
        [searchField setBackground: [UIImage imageNamed:@"searchbar"] ];
        [searchField setBorderStyle:UITextBorderStyleNone];

        //设置placeholder的颜色
        [searchField setValue:[UIColor whiteColor] forKeyPath:@"_placeholderLabel.textColor"];

        //设置searchField上的照片
        UIImage *image = [UIImage imageNamed:@"search"];
        UIImageView *iView = [[UIImageView alloc] initWithImage:image];
        iView.frame = CGRectMake(0, 0, 15, 15);
        searchField.leftView = iView;
    }

}

@end

seachBar=[[UISearchBar alloc] init]; 
seachBar.backgroundColor=[UIColor clearColor]; 
for (UIView *subview in seachBar.subviews){   
    if ([subview isKindOfClass:NSClassFromString(@"UISearchBarBackground")])  {   
        [subview removeFromSuperview];   
    break; 
    }  
}

for (UIView *subView in self.searchBar.subviews)
{
 for (UIView *secondLevelSubview in subView.subviews){
  if ([secondLevelSubview isKindOfClass:[UITextField class]])
  {
   UITextField *searchBarTextField = (UITextField *)secondLevelSubview;
   //set font color here
   searchBarTextField.textColor = [UIColor blackColor];
   break;
  }
 }
}

[[UITextField appearanceWhenContainedIn:[UISearchBar class], nil] setTextColor:[UIColor blueColor]];

- (void)setTextColor:(UIColor*)color
{
 for (UIView *v in self.subviews)
 {
  if([Environment isVersion7OrHigher]) //checks UIDevice#systemVersion   
  {
   for(id subview in v.subviews)
   {
    if ([subview isKindOfClass:[UITextField class]])
    {
     ((UITextField *)subview).textColor = color;
    }
   }
  }
  else
  {
   if ([v isKindOfClass:[UITextField class]])
   {
    ((UITextField *)v).textColor = color;
   }
  }
 }
}

- (void)layoutSubviews {
    UITextField *searchField;
    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];
        }
    }
    if(!(searchField == nil)) {
        searchField.textColor = [UIColor whiteColor];
        [searchField.leftView setHidden:YES];
        [searchField setBackground: [UIImage imageNamed:@"SearchBarBackground.png"] ];
        [searchField setBorderStyle:UITextBorderStyleNone];
    }
     
    [super layoutSubviews];
}