在uisearchbar中删除uitextfield的边框

Question

我想将UISearchBar控件自定义为如下图所示的样式:

首先我应该删除背景视图,然后找出UISearchBar中的UITextfiled,扩展UITextfiled的框架并删除它的边界.

这是我的代码:

UITextField *searchField;

NSUInteger numViews = [self.subviews count];
for(int i = 0; i != numViews; i++) {
    if([[self.subviews objectAtIndex:i] isKindOfClass:[UITextField class]]) { //conform?
        searchField = [self.subviews objectAtIndex:i];
    }
}
if(!(searchField == nil)) {

    [searchField setBorderStyle:UITextBorderStyleNone];
    searchField.frame = self.frame; //modify the frame
}

[[self.subviews objectAtIndex:0]removeFromSuperview]; //remove the background.

结果是UITextField的边界仍然存在.:(

我的问题是:1.为什么我不能修改UISearchBar的UITextField的外观？

2.如何在UISearchBar中删除UITextfield的边界.

非常感谢!

Answer 1

子类UISearchBar并覆盖layoutSubViews以删除搜索栏背景和文本字段边框子视图:

- (void)layoutSubviews
{    
    [super layoutSubviews];

    for (UIView *subview in self.subviews) {
        // Remove the default background
        if ([subview isKindOfClass:NSClassFromString(@"UISearchBarBackground")]) {
            [subview removeFromSuperview];
        }

        // Remove the rounded corners
        if ([subview isKindOfClass:NSClassFromString(@"UITextField")]) {
            UITextField *textField = (UITextField *)subview;
            for (UIView *subsubview in textField.subviews) {
               if ([subsubview isKindOfClass:NSClassFromString(@"UITextFieldBorderView")]) {
                    [subsubview removeFromSuperview];
                }
            }
        }
    }
}