UISearchBar

searchBar建立在view上的问题

要先创建一个底部view, 然后将searchBar添加到该view上面

 //除去在搜索框后面的灰色背景
[_searchBar.subviews[0].subviews[0] removeFromSuperview];
[_searchBackView addSubview:_searchBar];

更改searchBar内部textField的尺寸

新建一个类继承UISearchBar, 重写layoutSubviews,

要区分两种情景, 即是否需要右侧有个取消按钮.

如果不需要, 则直接让textField尺寸和外部设置的searchBar尺寸一致即可;

如果需要, 则外部传进来的宽度, 原点坐标和高度随searchBar尺寸即可

- (void)layoutSubviews{

[super layoutSubviews];

// view是searchBar中的唯一的直接子控件
for (UIView *view in self.subviews) {
    for (UIView *subView in view.subviews) {
        if ([subView isKindOfClass:[UITextField class]]) {
            UITextField *t = (UITextField *)subView;
            
            if (!self.showsCancelButton) {
                
                t.frame = self.bounds;
            }
            else{
                CGFloat height = self.bounds.size.height;
                t.frame = CGRectMake(self.bounds.origin.x, self.bounds.origin.y, _width, height);
            }
        }
    }
}
}

修改右侧取消按钮字体颜色大小等参数

记得_searchBar.showsCancelButton = YES;

UIView *topView = _searchBar.subviews[0];
for(UIView *subView in topView.subviews) {
    
    if([subView isKindOfClass:NSClassFromString(@"UINavigationButton")]) {
        UIButton *cancelButton = (UIButton *)subView;
        cancelButton.titleLabel.font = [UIFont systemFontOfSize:15 * SCALE_WIDTH];
        [cancelButton setTitleColor:THEME_COLOR forState:UIControlStateNormal];
        cancelButton.enabled = YES;//UISearchBar失去焦点时, 取消按钮enable为NO
        break;
    }
}

修改searchBar里面textField的背景颜色(默认是白色)

UIView *searchTextField = nil;
_searchBar.barTintColor = [UIColor whiteColor];
searchTextField = [[[_searchBar.subviews firstObject] subviews] lastObject];
searchTextField.backgroundColor = kRGBColor(239, 239, 243);

修改searchBar里面textField的圆角

 UITextField *searchField = [_searchBar valueForKey:@"searchField"];
if (searchField) {
    searchField.layer.cornerRadius = 10.0f;
}

取消按钮中英文切换

在Project中info，在Localizations默认只有English这一项, 我们只需在Localizations上添加Chinese就可以了, 你还可以根据你的需要添加其他的语言.
如果用户把手机语言设成英文, 那么显示的就是英文, 设置成中文,那么显示的就是中文.

感谢 http://blog.sina.com.cn/s/blog_7f6480790101fvlk.html

在serachBar内部右侧增加扫描按钮

先写个按钮的懒加载

#pragma mark 扫描按钮懒加载
- (NABaseButton *)btnOfScan{
if (!_btnOfScan) {
    CGFloat myWidth = 16.0f;
    CGFloat myHeight = 16.0f;
    _btnOfScan = [NABaseButton buttonWithType:UIButtonTypeCustom];
    _btnOfScan.frame = CGRectMake(0.0f, 0.0f, myWidth, myHeight);
    [_btnOfScan setImage:[UIImage imageNamed:@"searchBarScan"] forState:UIControlStateNormal];
    [_btnOfScan addTarget:self action:@selector(clickSearchBarRightView:) forControlEvents:UIControlEventTouchUpInside];
}
return _btnOfScan;
}

在视图已经出现的时候

#pragma mark - 视图已经出现
- (void)viewDidAppear:(BOOL)animated{
[super viewDidAppear:animated];

for(UIView *subView in _searchController.searchBar.subviews.firstObject.subviews) {
    if([subView isKindOfClass: [UITextField class]]){
        UITextField *searchField = (UITextField *)subView;
        searchField.rightView = self.btnOfScan;
        searchField.rightViewMode = UITextFieldViewModeAlways;
        searchField.clearButtonMode = UITextFieldViewModeNever;
    }
}
}