IOS之表视图添加搜索栏

        下面是我们要实现的效果。本效果是在上一篇自定义表视图的基础上进行更改的。http://ikrboy.iteye.com/blog/2004032

   

1.将Search bar and search display拖动到ViewController中。不要添加Search Bar.

2.修改ViewController的头文件

#import <UIKit/UIKit.h>

@interface IkrboyViewController4 : UIViewController
{
    NSArray *dataArr;//用于显示表视图的数据
    NSArray *allDataArr;//存储所有数据，通过关键词搜索将搜索结果赋值给dataArr
}
@property (weak, nonatomic) IBOutlet UISearchBar *searchBar;

@end

 3.修改自定义方法initTableViewData。将ScopeBar隐藏是考虑到iphone的显示高度问题。可自行决定。

-(void)initTableViewData{
    NSBundle *bundle = [NSBundle mainBundle];
    NSString *plistPath = [bundle pathForResource:@"user_head" ofType:@"plist"];
    allDataArr = [[NSArray alloc] initWithContentsOfFile:plistPath];
    dataArr = [NSArray arrayWithArray:allDataArr];
    NSLog(@"table data count = %d",[allDataArr count]);
    
    //设定搜索栏ScopeBar隐藏
    [self.searchBar setShowsScopeBar:NO];
    [self.searchBar sizeToFit];
}

4.添加SearchBar的三个事件触发

//以下三个方法实现SearchBar的搜索功能
//当文本内容发生改变时候，向表视图数据源发出重新加载消息
- (BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchString:(NSString *)searchString
{
    [self filterContentForSearchText:searchString scope:self.searchBar.selectedScopeButtonIndex];
    //YES情况下表视图可以重新加载
    return YES;
}

// 当Scope Bar选择发送变化时候，向表视图数据源发出重新加载消息
- (BOOL)searchDisplayController:(UISearchDisplayController *)controller shouldReloadTableForSearchScope:(NSInteger)searchOption
{
    [self filterContentForSearchText:self.searchBar.text scope:searchOption];
    // YES情况下表视图可以重新加载
    return YES;
}

//点击cancel按钮的事件
- (void)searchBarCancelButtonClicked:(UISearchBar *)searchBar
{
    //查询所有
    [self filterContentForSearchText:@"" scope:-1];
}

 
 5.自定义关键词搜索功能

//自定义搜索方法，根据关键词从allDataArr中搜索到满足搜索条件的元素，并将匹配的数组赋值给dataArr，由于dataArr是表视图的数据源，因此表视图的记录也会随之改变。
- (void)filterContentForSearchText:(NSString*)searchText scope:(NSUInteger)scope;
{
    if([searchText length]==0)
    {
        //查询所有
        dataArr = [NSArray arrayWithArray:allDataArr];
        NSLog(@"dataArr count = %d",[dataArr count]);
        return;
    }
    
    NSPredicate *scopePredicate;
    
    switch (scope) {
        case 0:
            scopePredicate = [NSPredicate predicateWithFormat:@"(SELF.itemName contains[c] %@) OR (SELF.itemImagePath contains[c] %@)",searchText,searchText];
            NSLog(@"searchText=%@",searchText);
            dataArr =[NSArray arrayWithArray:[allDataArr filteredArrayUsingPredicate:scopePredicate]];
            break;
        case 1:
            scopePredicate = [NSPredicate predicateWithFormat:@"SELF.itemName contains[c] %@",searchText];
            dataArr = [NSArray arrayWithArray:[allDataArr filteredArrayUsingPredicate:scopePredicate]];
            break;
        case 2:
            scopePredicate = [NSPredicate predicateWithFormat:@"SELF.itemImagePath contains[c] %@",searchText];
            dataArr =[NSArray arrayWithArray:[allDataArr filteredArrayUsingPredicate:scopePredicate]];
            break;
    }
}

 6.修改cellForRowAtIndexPath方法

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"myTableCell";
    MyTableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    //add code begin:important,for showing searching results
    //不对cell进行空值的判断，会导致在搜索时，找不到对应identifier的cell而报错。
    if (cell == nil) {
    //搜索结果采用简单表视图cell的style，并非自定义的表视图cell的style    
    cell = [[MyTableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier];
        NSUInteger row = [indexPath row];
        NSDictionary *rowDict = [dataArr objectAtIndex:row];
        cell.textLabel.text =  [rowDict objectForKey:@"itemName"];
        NSString *imagePath = [rowDict objectForKey:@"itemImagePath"];
        cell.imageView.image =  [UIImage imageNamed:imagePath];
    }
    //add code end

    NSUInteger row = [indexPath row];
    NSDictionary *rowDict = [dataArr objectAtIndex:row];
    cell.label.text =  [rowDict objectForKey:@"itemName"];
    NSLog(@"cell.label.text =  %@",[rowDict objectForKey:@"itemName"]);
    
    NSString *imagePath = [rowDict objectForKey:@"itemImagePath"];
    cell.image.image = [UIImage imageNamed:imagePath];
    NSLog(@"cell.image.image  =  %@",imagePath);
    
    cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
    
    return cell;
}