如何将搜索栏添加到使用带有NSDictionaries的数组的TableView

Question

到目前为止，我所做的是让搜索栏工作。

- (void)viewDidLoad
{

[self makeData];

[super viewDidLoad];

self.mySearchBar.delegate = self;
self.myTableView.delegate = self;
self.myTableView.dataSource = self;

//Feedback button code here
UIBarButtonItem *feedback;
feedback = [[UIBarButtonItem alloc] initWithTitle:@"Contact"   style:UIBarButtonItemStylePlain
target:self action:@selector(showEmail:)];
self.navigationItem.leftBarButtonItem = feedback;


[self.tableView reloadData];
self.tableView.scrollEnabled = YES;

}

-(void) makeData; {

list = [[NSMutableArray alloc] init];

[list addObject:[[NSMutableDictionary alloc]
                initWithObjectsAndKeys:@"Acceleration", @"name" ,
                @"acceleration.png", @"image" ,
                @"Acceleration", @"description" ,nil]];

[list addObject:[[NSMutableDictionary alloc]
                initWithObjectsAndKeys:@"Alternating Current", @"name" ,
                @"alternating current.png", @"image" ,
                @"Alternating Current", @"description" ,nil]];

[list addObject:[[NSMutableDictionary alloc]
                initWithObjectsAndKeys:@"Ampere", @"name" ,
                @"ampere.png", @"image" ,
                @"Ampere", @"description" ,nil]];

[list addObject:[[NSMutableDictionary alloc]
                initWithObjectsAndKeys:@"Amplitude", @"name" ,
                @"amplitude.png", @"image" ,
                @"Amplitude", @"description" ,nil]];


}

-(void)searchBar:(UISearchBar *)searchBar textDidChange:(NSString *)searchText
{
if (searchText.length == 0) {
    isFiltered = FALSE;
}
else
{
    isFiltered = TRUE;
    filteredList = [[NSMutableArray alloc] init];

    for (NSString *str in list) {
        NSRange stringRange = [str rangeOfString:searchText options:NSCaseInsensitiveSearch];

        if (stringRange.location != NSNotFound) {
            [filteredList addObject:str];
        }
    }
}
[self.myTableView reloadData];
}

-(void)searchBarSearchButtonClicked:(UISearchBar *)searchBar
{
[self.myTableView reloadData];
}

然而，每次我尝试在应用程序中键入某些内容时，都会崩溃，并收到以下消息：

2013-05-29 11:36:09.734 PhysEX[4770:c07] -[__NSDictionaryM rangeOfString:options:]: unrecognized selector sent to instance 0x9468cd0
2013-05-29 11:36:09.735 PhysEX[4770:c07] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSDictionaryM rangeOfString:options:]: unrecognized selector sent to instance 0x9468cd0'

如何让我的搜索工作？

Answer 1

textDidChange委托中的以下代码不正确：

for (NSString *str in list) {
    ...
}

这是因为列表数组中的对象不是NSString，而是NSDictionary。因此会出现错误消息，指出NSDictionary无法识别选择器rangeOfString:options：，因为该选择器用于NSString实例。

相反，您需要搜索NSDictionary值。

for (NSDictionary *theDictionary in list) {

    for (NSString *key in theDictionary) {
        NSString *value = [theDictionary objectForKey:key];
        NSRange stringRange = [value rangeOfString:searchText options:NSCaseInsensitiveSearch];

        if (stringRange.location != NSNotFound) {
            [filteredList addObject:theDictionary];
            break;
        }
   }
}