/**
1. 顶部toolbar
2. TextField可以以UIBarButtonItem的自定义视图的方式加入toolbar
3. 三个按钮
4. 将UIBarButtonItem加入toolBar
**/
UIToolbar *toolBar = [[UIToolbar alloc]initWithFrame:CGRectMake(0, 0, 320, 44)];
[self.view addSubview:toolBar];
UITextField *textField = [[UITextField alloc]initWithFrame:CGRectMake(10, 6, 200, 32)];
[textField setBorderStyle:UITextBorderStyleRoundedRect];// 设置边框
[textField setContentVerticalAlignment:UIControlContentVerticalAlignmentCenter];// 设置垂直对齐
[textField setClearButtonMode:UITextFieldViewModeWhileEditing];// 设置清除按钮
[textField setDelegate:self];
UIBarButtonItem *addressItem = [[UIBarButtonItem alloc]initWithCustomView:textField];
//初始化UIBarButtonItem方法1
UIBarButtonItem *item1 = [[UIBarButtonItem alloc] initWithBarButtonSystemItem:UIBarButtonSystemItemRewind target:self action:@selector(todo1)];
//初始化UIBarButtonItem方法2
UIBarButtonItem *item1 = [[UIBarButtonItem alloc]initWithTitle:@"buttonName " style:UIBarButtonItemStyleBordered target:self action:@selector(btClick)];
[toolBar setItems:@[addressItem, item1, item2, item3]];
// 设置状态栏样式，因为改变bar的时候状态栏颜色会默认变成和bar一样的颜色
[UIApplication sharedApplication].statusBarStyle = UIStatusBarStyleBlackOpaque;
组件_UISearchBar
//初始化
UISearchBar *search = [[UISearchBar alloc] init];
search.autoresizingMask = UIViewAutoresizingFlexibleWidth;//可以伸缩的宽度
search.frame = CGRectMake(0, 0, self.view.frame.size.width, kSearchH);
search.delegate = self;
[self.view addSubview:search];
_searchBar = search;
//代理方法
#pragma mark 监听搜索框的文字改变
- (void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText
#pragma mark 搜索框开始编辑（开始聚焦）
- (void)searchBarTextDidBeginEditing:(UISearchBar *)searchBar