iphone - 我在 UITableView 中使用搜索有很大延迟

Question

有我的问题，我有一个应用程序有大量的数据。我的 .plist 文件包含元素数组，它看起来像这样 - 橙色、蛋白质 - 25、碳水化合物 - 40、脂肪 - 50 等。总共，每个项目包含 7 行带有数据的子行。

我的 tableview 在一个巨大的 tableview 中显示了所有带有部分的数组。在屏幕顶部我有一个搜索栏。当我点击搜索栏并输入任何字母时，它会显示这样的新数组 - M：巨无霸、肉类、膳食等。

所以，在我的数组中达到 700 多个元素之前，一切都很好，但是，当我添加最后 500 个元素（我的 .plist 文件从 200 到 700 个元素编辑）时，我意识到当我点击搜索并输入任何字母时，我有很大的延迟。第一次延迟大约 0.6 秒（当我点击搜索字段时），在我按下键盘上的按钮后第二次延迟（再次大约 0.6 秒）。我认为，那是因为我在我的 .plist 中添加了许多项目。

显然，我不想减少数组中对象的数量。我想我有“坏”的代码，我向你寻求任何有用的建议。请帮助我，我想我需要改进它！有我的代码，其中包含我的 UITableView 代码和搜索方法：

- (void)viewDidLoad 
{
    [super viewDidLoad];

    self.tableView.backgroundColor=[UIColor colorWithPatternImage:[UIImage imageNamed:@"bg.png"]];


    NSString *path = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)lastObject]stringByAppendingPathComponent:@"food.plist"];

    listOfItems = [[NSMutableArray alloc]initWithContentsOfFile:path];
    searchListOfItems = [[NSMutableArray alloc]init];

    searchBar = [[UISearchBar alloc] initWithFrame:CGRectMake(0, 0, 320, 45)];
    searchBar.barStyle = UIBarStyleBlackTranslucent;
    searchBar.showsCancelButton = NO;
    searchBar.autocorrectionType=UITextAutocorrectionTypeNo;
    searchBar.autocapitalizationType=UITextAutocapitalizationTypeNone;
    searchBar.delegate= self; 
    [[self tableView] setTableHeaderView:searchBar];


    searching = NO;
    letUserSelectRow = YES;
    UIBarButtonItem *addButton = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemAdd target:self action:@selector(addProduct:)];
    self.navigationItem.leftBarButtonItem = addButton;
    self.navigationItem.backBarButtonItem.title = @"Back";


    [self.tableView reloadData];

    self.navigationItem.backBarButtonItem =
    [[UIBarButtonItem alloc] initWithTitle:@"Назад"
                                     style:UIBarButtonItemStyleBordered
                                    target:nil
                                    action:nil];




    self.title = @"Продукты";
    UILabel* tlabel=[[UILabel alloc] initWithFrame:CGRectMake(0,0, 125, 21)];
    tlabel.text=self.navigationItem.title;
    tlabel.font = [UIFont fontWithName:@"Chalkboard SE" size:17];
    tlabel.textAlignment = UITextAlignmentCenter;
    tlabel.textColor=[UIColor whiteColor];
    tlabel.backgroundColor =[UIColor clearColor];
    tlabel.adjustsFontSizeToFitWidth=YES;
    self.navigationItem.titleView=tlabel;


}

- (void)hideModalViewController:(NSNotification *)notif
{
    [self dismissModalViewControllerAnimated:YES];
    [self viewDidLoad];   
}

-(void)productAdded {
    [self.tableView setContentOffset:CGPointMake(0, self.tableView.contentSize.height - self.tableView.frame.size.height)];
    [self.tableView reloadData];
}

- (void)addProduct:(UIBarButtonItem *)button
{
    BIDAddProductViewController *addProductVC = [[BIDAddProductViewController alloc]init];
    addProductVC.delegate = self;
    [self.navigationController pushViewController:addProductVC animated:YES];

    [[NSNotificationCenter defaultCenter]addObserver:self selector:@selector(hideModalViewController:) name:@"HideModalViewController" object:addProductVC];
}

- (void)viewDidUnload
{
    [super viewDidUnload];
    self.childController = nil;
    self.tableView=nil;

}

- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{

    NSDictionary *dictionary = [listOfItems objectAtIndex:indexPath.section];

    if (editingStyle == UITableViewCellEditingStyleDelete)

    {

        NSString *path = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)lastObject]stringByAppendingPathComponent:@"food.plist"];

        NSMutableArray *listOfItemsToDelete = [[NSMutableArray alloc]initWithContentsOfFile:path];

        [[[listOfItemsToDelete objectAtIndex:indexPath.section]objectForKey:@"Products"] removeObjectAtIndex:indexPath.row];
        [listOfItemsToDelete writeToFile:path atomically:YES];
        [self viewDidLoad];


        NSArray *descriptionsArray = [[dictionary objectForKey:@"Products"]valueForKeyPath:@"ProductName"];

        NSLog(@"%@", descriptionsArray);
        NSLog(@"%i", [descriptionsArray count]);

        if ([descriptionsArray count]<2){


            [listOfItems removeObjectAtIndex:indexPath.section];
            [tableView deleteSections:[NSIndexSet indexSetWithIndex:indexPath.section] withRowAnimation:NO];
            [listOfItems writeToFile:path atomically:YES];
        }



        }
}
- (UITableViewCellEditingStyle)tableView:(UITableView *)tableView editingStyleForRowAtIndexPath:(NSIndexPath *)indexPath
{
    return UITableViewCellEditingStyleDelete;
}

- (UITableViewCell *)tableView:(UITableView *)tableView
         cellForRowAtIndexPath:(NSIndexPath *)indexPath {



    static NSString *SectionsTableIdentifier = @"SectionsTableIdentifier";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:
                             SectionsTableIdentifier];



    if (cell == nil) {
        cell = [[UITableViewCell alloc]
                initWithStyle:UITableViewCellStyleValue1
                reuseIdentifier:SectionsTableIdentifier];
    }

    if(searching)
        cell.textLabel.text = [[searchListOfItems objectAtIndex:indexPath.row]valueForKey:@"ProductName"];
    else {

        NSDictionary *dictionary = [listOfItems objectAtIndex:indexPath.section];
         NSArray *array = [[dictionary objectForKey:@"Products"]valueForKeyPath:@"ProductName"];
        NSString *cellValue = [array objectAtIndex:indexPath.row];
        cell.textLabel.text = cellValue;


    }


    cell.accessoryType = UITableViewCellAccessoryDetailDisclosureButton;
    return cell;
}

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {

    if (searching)
        return 1;
    else
        return [listOfItems count];
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {

    if (searching)
        return [searchListOfItems count];
    else {

        NSDictionary *dictionary = [listOfItems objectAtIndex:section];
        NSArray *array = [dictionary objectForKey:@"Products"];
        return [array count];
    }
}

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section {

    if(searching)
        return @"";

   return [[listOfItems objectAtIndex:section]valueForKey:@"SectionName"];
}

- (void) doneSearching_Clicked:(id)sender {

    searchBar.text = @"";
    [searchBar resignFirstResponder];

    letUserSelectRow = YES;
    searching = NO;
    self.navigationItem.rightBarButtonItem = nil;
    self.tableView.scrollEnabled = YES;
    [self.tableView reloadData];

}
- (void) searchBarSearchButtonClicked:(UISearchBar *)theSearchBar {

    [self searchTableView];
}

- (void) searchTableView {

    NSString *searchText = searchBar.text;
    NSMutableArray *searchArray = [[NSMutableArray alloc] init];

    for (NSDictionary *dictionary in listOfItems)
    {
        NSArray *array = [dictionary objectForKey:@"Products"];
        [searchArray addObjectsFromArray:array];
    }

    for (NSString *sTemp in [searchArray valueForKeyPath:@"ProductName"] )
    {
        NSRange titleResultsRange = [sTemp rangeOfString:searchText options:NSCaseInsensitiveSearch];

        if (titleResultsRange.length > 0)
            [searchListOfItems addObject:[searchArray objectAtIndex:[[searchArray valueForKeyPath:@"ProductName"]indexOfObject:sTemp]]];
    }

    searchArray = nil;
}
- (NSIndexPath *)tableView :(UITableView *)theTableView willSelectRowAtIndexPath:(NSIndexPath *)indexPath {

    if(letUserSelectRow)
        return indexPath;
    else
        return nil;
}
- (void) searchBarTextDidBeginEditing:(UISearchBar *)theSearchBar {

    searching = YES;

    self.navigationItem.rightBarButtonItem = [[UIBarButtonItem alloc]
                                               initWithBarButtonSystemItem:UIBarButtonSystemItemDone
                                               target:self action:@selector(doneSearching_Clicked:)];
}

- (void)searchBar:(UISearchBar *)theSearchBar textDidChange:(NSString *)searchText {

    [searchListOfItems removeAllObjects];

    if([searchText length] > 0) {

        searching = YES;
        letUserSelectRow = YES;
        self.tableView.scrollEnabled = YES;
        [self searchTableView];
    }
    else {

        searching = NO;
        letUserSelectRow = NO;
        self.tableView.scrollEnabled = NO;
    }

    [self.tableView reloadData];
}
- (void)viewWillAppear:(BOOL)animated
{


    letUserSelectRow = YES;
    [super viewWillAppear:animated];


}

#pragma mark -
#pragma mark Table Delegate Methods
- (void)tableView:(UITableView *)tableView
    didSelectRowAtIndexPath:(NSIndexPath *)indexPath 
{
    if (childController == nil) {
        childController = [[BIDDisclosureDetailController alloc]
                           initWithNibName:@"BIDDisclosureDetail" bundle:nil];
    }

        if(searching)

        {


            childController.description = [[searchListOfItems objectAtIndex:indexPath.row]valueForKey:@"ProductName"];
//            childController.title = [[searchListOfItems objectAtIndex:indexPath.row]valueForKey:@"ProductName"];
            childController.calories = [[searchListOfItems objectAtIndex:indexPath.row]valueForKey:@"Calories"];
            childController.protein = [[searchListOfItems objectAtIndex:indexPath.row]valueForKey:@"Proteins"];
            childController.carbohydrates = [[searchListOfItems objectAtIndex:indexPath.row]valueForKey:@"Carbohydrates"];
            childController.fat = [[searchListOfItems objectAtIndex:indexPath.row]valueForKey:@"Fat"];
            childController.myBool=[[searchListOfItems objectAtIndex:indexPath.row]valueForKey:@"TextField"];

        }

        else 

        {


            NSDictionary *dictionary = [listOfItems objectAtIndex:indexPath.section];

            NSArray *descriptionsArray = [[dictionary objectForKey:@"Products"]valueForKeyPath:@"ProductName"];
            childController.description = [descriptionsArray objectAtIndex:indexPath.row];


            NSArray *proteinArray = [[dictionary objectForKey:@"Products"]valueForKeyPath:@"Proteins"];
            childController.protein = [proteinArray objectAtIndex:indexPath.row];

            NSArray *carbohydratesArray = [[dictionary objectForKey:@"Products"]valueForKeyPath:@"Carbohydrates"];
            childController.carbohydrates = [carbohydratesArray objectAtIndex:indexPath.row];

            NSArray *fatArray = [[dictionary objectForKey:@"Products"]valueForKeyPath:@"Fat"];
            childController.fat = [fatArray objectAtIndex:indexPath.row];

            NSArray *caloriesArray = [[dictionary objectForKey:@"Products"]valueForKeyPath:@"Calories"];
            childController.calories = [caloriesArray objectAtIndex:indexPath.row];

             NSArray *textFieldArray = [[dictionary objectForKey:@"Products"]valueForKeyPath:@"TextField"];
            childController.myBool = [textFieldArray    objectAtIndex:indexPath.row];






        }

        [self.navigationController pushViewController:childController
                                             animated:YES];
    }

@end

score 1 · Accepted Answer

In your code every time you change the text in the search bar the searchTableView function is run. You will want to make sure this function is as quick as possible.

I see you are iterating over the list of NSDictionarys from the plist file in the function and building a search array. If the plist is large this is probably quite expensive of an operation to be doing on every text change.

for (NSDictionary *dictionary in listOfItems)
{
    NSArray *array = [dictionary objectForKey:@"Products"];
    [searchArray addObjectsFromArray:array];
}

I think if you moved this iteration to viewDidLoad and made searchArray a global variable you will notice some speed increases.

Hope this helps.

score 0 · Accepted Answer

I think you should use SqliteDatabase to store so much data,and use SQL to search your data.Every time you touch search bar,all of your data alloc in a new NSMutableArray with the method

-(void)searchTableView

this is why when you touch the search bar , it will delay 0.6sec when your data is too much

iphone - 我在 UITableView 中使用搜索有很大延迟

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