UITableView 是开发中使用十分频繁的控件，本系列记录UITableView的进阶使用：UITableView的搜索栏和字母索引表。
不想看我废话的可以直接到gitHub仓库下载源码😏。 UITableView使用进阶gitHub源码
搜索栏有两种实现方式，第一种是通过UISearchBar和UISearchDisplayController实现，第二种是通过UISearchController实现。而在iOS8.0之后，苹果官方推荐使用第二种方式。
本文使用的是第二种方式（UISearchController），不过源码中也实现了第一种(UISearchBar+UISearchDisplayController)。关于UISearchBar和UISearchDisplayController的使用，可以参考我的另一篇文章：UISearchBar和UISearchDisplayController实现搜索栏
本文先介绍UITableView的搜索栏（UISearchController），是一个显示美国总统的TableView。
Step1. 创建President类
创建一个名为President的Objective-C类，它继承于NSObject类，用于保存总统的姓氏和名字。定义一个静态方法，用来创建President对象，并且对firstName和lastName赋值。
President.h
#import <Foundation/Foundation.h>
@interface President : NSObject
@property (nonatomic, retain) NSString *firstName;
@property (nonatomic, retain) NSString *lastName;
+ (President *) presidentWithFirstName: (NSString *)firstname lastName: (NSString *)lastname;
@end
President.m
#import "President.h"
@implementation President
+ (President *) presidentWithFirstName:(NSString *)firstname lastName:(NSString *)lastname {
President *president = [[President alloc] init];
president.firstName = firstname;
president.lastName = lastname;
return president;
}
@end
Step2. 编写ViewController
viewController.h
#import <UIKit/UIKit.h>
@interface ViewController : UIViewController
@property (nonatomic, strong) UITableView *mTableView;
@property (nonatomic, strong) NSArray *presidents;//所有总统
@property (nonatomic, strong) NSArray *filteredPresidents;//保存搜索结果
@property (nonatomic, retain) UISearchController *searchController;
@end
viewController.m
#import "ViewController.h"
#import "President.h"
@interface ViewController () <UITableViewDataSource, UITableViewDelegate, UISearchBarDelegate, UISearchResultsUpdating, UISearchDisplayDelegate>
@end
@implementation ViewController
- (void)viewDidLoad {
[super viewDidLoad];
//初始化数据
self.presidents = [[NSArray alloc] initWithObjects:
[President presidentWithFirstName:@"George" lastName:@"Washington"],
[President presidentWithFirstName:@"John" lastName:@"Adams"],
[President presidentWithFirstName:@"Thomas" lastName:@"Jeffeson"],
[President presidentWithFirstName:@"James" lastName:@"Madison"],
[President presidentWithFirstName:@"James" lastName:@"Monroe"],
[President presidentWithFirstName:@"John Quincy" lastName:@"Adams"],
[President presidentWithFirstName:@"Andrew" lastName:@"Jackson"],
[President presidentWithFirstName:@"Martin" lastName:@"van Buren"],
[President presidentWithFirstName:@"William Henry" lastName:@"Harrison"],
[President presidentWithFirstName:@"John" lastName:@"Tyler"],
[President presidentWithFirstName:@"James K" lastName:@"Polk"],
[President presidentWithFirstName:@"Zachary" lastName:@"Taylor"],
[President presidentWithFirstName:@"Millard" lastName:@"Fillmore"],
[President presidentWithFirstName:@"Franklin" lastName:@"Pierce"],
[President presidentWithFirstName:@"James" lastName:@"Buchanan"],
[President presidentWithFirstName:@"Abraham" lastName:@"Lincoln"],
[President presidentWithFirstName:@"Andrew" lastName:@"Johnson"],
[President presidentWithFirstName:@"Ulysses S" lastName:@"Grant"],
[President presidentWithFirstName:@"Rutherford B" lastName:@"Hayes"],
[President presidentWithFirstName:@"James A" lastName:@"Garfield"],
[President presidentWithFirstName:@"Chester A" lastName:@"Arthur"],
[President presidentWithFirstName:@"Grover" lastName:@"Cleveland"],
[President presidentWithFirstName:@"Bejamin" lastName:@"Harrison"],
[President presidentWithFirstName:@"Grover" lastName:@"Cleveland"],
[President presidentWithFirstName:@"William" lastName:@"McKinley"],
[President presidentWithFirstName:@"Theodore" lastName:@"Roosevelt"],
[President presidentWithFirstName:@"William Howard" lastName:@"Taft"],
[President presidentWithFirstName:@"Woodrow" lastName:@"Wilson"],
[President presidentWithFirstName:@"Warren G" lastName:@"Harding"],
[President presidentWithFirstName:@"Calvin" lastName:@"Coolidge"],
[President presidentWithFirstName:@"Herbert" lastName:@"Hoover"],
[President presidentWithFirstName:@"Franklin D" lastName:@"Roosevelt"],
[President presidentWithFirstName:@"Harry S" lastName:@"Truman"],
[President presidentWithFirstName:@"Dwight D" lastName:@"Eisenhower"],
[President presidentWithFirstName:@"John F" lastName:@"Kennedy"],
[President presidentWithFirstName:@"Lyndon B" lastName:@"Johnson"],
[President presidentWithFirstName:@"Richard" lastName:@"Nixon"],
[President presidentWithFirstName:@"Gerald" lastName:@"Ford"],
[President presidentWithFirstName:@"Jimmy" lastName:@"Carter"],
[President presidentWithFirstName:@"Ronald" lastName:@"Reagan"],
[President presidentWithFirstName:@"George H W" lastName:@"Bush"],
[President presidentWithFirstName:@"Bill" lastName:@"Clinton"],
[President presidentWithFirstName:@"George W" lastName:@"Bush"],
[President presidentWithFirstName:@"Barack" lastName:@"Obama"],
nil];
CGRect appFrame = [[UIScreen mainScreen] bounds];
//创建tableview
self.mTableView = [[UITableView alloc] initWithFrame:CGRectMake(0, 20, appFrame.size.width, appFrame.size.height - 20) style:UITableViewStylePlain];
self.mTableView.delegate = self;
self.mTableView.dataSource = self;
[self.view addSubview:self.mTableView];
//创建searchController
self.searchController = [[UISearchController alloc] initWithSearchResultsController:nil];
self.searchController.searchResultsUpdater = self;
self.searchController.dimsBackgroundDuringPresentation = NO;
self.searchController.hidesNavigationBarDuringPresentation = NO;
//设置tableview的搜索栏
self.mTableView.tableHeaderView = self.searchController.searchBar;
}
#pragma mark - tableView Delegate
- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
if (self.searchController.active) {
return [self.filteredPresidents count];
} else {
return [self.presidents count];
}
}
#pragma mark - tableView Datasource
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
static NSString *cellId = @"cellId";
UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:cellId];
if (!cell) {
cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:cellId];
}
President *president;
if (self.searchController.active) {
president = [self.filteredPresidents objectAtIndex:indexPath.row];
} else {
president = [self.presidents objectAtIndex:indexPath.row];
}
cell.textLabel.text = [NSString stringWithFormat:@"%@ %@", president.firstName, president.lastName];
return cell;
}
#pragma mark - SearchController delegate
- (void)updateSearchResultsForSearchController:(UISearchController *)searchController {
NSString *searchString = [self.searchController.searchBar text];
NSPredicate *predicate = [NSPredicate predicateWithFormat:@"firstName CONTAINS[cd] %@ OR lastName CONTAINS[cd] %@", searchString, searchString];
self.filteredPresidents = [self.presidents filteredArrayUsingPredicate:predicate];
//刷新表格
[self.mTableView reloadData];
}
- (void)didReceiveMemoryWarning {
[super didReceiveMemoryWarning];
// Dispose of any resources that can be recreated.
}
@end
实现效果
