iphone - 索引在 TableView 中不起作用

Question

我正在尝试在表格上实现索引，因为我使用以下方法索引出现在右侧，但它不起作用代码在下面

    - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
        return 2;
    }

    - (NSArray *)sectionIndexTitlesForTableView:(UITableView *)tableView {

        NSArray *toBeReturned = [NSArray arrayWithArray:
                                 [@"A|B|C|D|E|F|G|H|I|J|K|L|M|N|O|P|Q|R|S|T|U|V|W|X|Y|Z|#"
                                  componentsSeparatedByString:@"|"]];

        return toBeReturned;
    }


   - (NSInteger)tableView:(UITableView *)tableView sectionForSectionIndexTitle:(NSString *)title atIndex:(NSInteger)index {

    int foundIndex = 0;


    for (int i = 0; i< [mainArray count]; i++) {
        // Here you return the name i.e. Honda,Mazda
        // and match the title for first letter of name
        // and move to that row corresponding to that indexpath as below
        NSString *letterString = [[[mainArray valueForKey:@"name"] objectAtIndex:i] substringToIndex:1];

        NSLog(@"letterString%@",letterString);
        NSLog(@"title%@",title);

        if ([[letterString uppercaseString ] compare:title] == NSOrderedDescending){
            break;
            foundIndex++;        }

        if(foundIndex > mainArray.count)
            foundIndex = mainArray.count;
        [table scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:foundIndex inSection:0] atScrollPosition:UITableViewScrollPositionTop animated:YES];
        return 1;

    }
  }

   - (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath{

            return 120;


    }
    - (UITableViewCell *)tableView:(UITableView *)tableView

             cellForRowAtIndexPath:(NSIndexPath *)indexPath {

        static NSString *CellIdentifier = @"Cell";

        UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];

        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
       //—set the text to display for the cell—

        NSLog(@"%d",mainArray.count);
        NSLog(@"%@",mainArray);

        UIImageView *selectionView = [[UIImageView alloc] initWithFrame:CGRectMake(0, 0, 768, 120)];

        UIImage *image = [UIImage imageNamed:@"default.png"];
        UIImageView* blockView = [[UIImageView alloc] initWithImage:image];
        blockView.layer.cornerRadius = 4;
        blockView.layer.masksToBounds = YES;
        blockView.layer.borderWidth = 2;
        blockView.layer.borderColor = [UIColor blackColor].CGColor;

        blockView.frame = CGRectMake(5, 5, 110, 110);

      //  title isKindOfClass:[NSNull class]])
        //NSLog(@"%@",[[mainArray valueForKey:@"image"] objectAtIndex:[indexPath row]]);


        id obj = [[mainArray valueForKey:@"image"] objectAtIndex:[indexPath row]];
        if ([obj isKindOfClass:[NSString class]])
        {

            [selectionView addSubview:blockView];
        }

        else     {

            UIImage *contactImage = [[UIImage alloc]init];
            contactImage = [[mainArray valueForKey:@"image"] objectAtIndex:[indexPath row]];
            //  NSLog(@"  array%@",[[mainArray valueForKey:@"image"] objectAtIndex:[indexPath row]]);
            NSLog(@" image%@",contactImage);
            UIImageView *blockView = [[UIImageView alloc] initWithImage:contactImage];
            blockView.frame = CGRectMake(5, 5, 110, 110);
            blockView.layer.cornerRadius = 4;
            blockView.layer.masksToBounds = YES;
            blockView.layer.borderWidth = 2;
            blockView.layer.borderColor = [UIColor blackColor].CGColor;

            [selectionView addSubview:blockView];
        }

        NSLog(@" name :%@",[[mainArray valueForKey:@"name"] objectAtIndex:[indexPath row]]);

        if ([[[mainArray valueForKey:@"name"] objectAtIndex:[indexPath row]] isEqualToString:@"(null)"]) {
            UILabel *name = [[UILabel alloc]initWithFrame:CGRectMake(130, 10, 310, 55)];
            name.text =@"Name Not Available";
            [name setBackgroundColor:[UIColor clearColor]];
            [ name setFont:[UIFont fontWithName:@"Arial-BoldMT" size:30]];
            name.textColor = [UIColor whiteColor];
            [selectionView addSubview:name];
               }
        else{

            UILabel *name = [[UILabel alloc]initWithFrame:CGRectMake(130, 10, 310, 55)];
            name.text =[[mainArray valueForKey:@"name"] objectAtIndex:[indexPath row]];
            [name setBackgroundColor:[UIColor clearColor]];
            [ name setFont:[UIFont fontWithName:@"Arial-BoldMT" size:30]];
            name.textColor = [UIColor whiteColor];
            [selectionView addSubview:name];
        }

        if ([[[mainArray valueForKey:@"phone"] objectAtIndex:[indexPath row]] isEqualToString:@"Add Number"]) {

            UILabel *phone = [[UILabel alloc]initWithFrame:CGRectMake(130, 70, 300, 50)];
            phone.text =@"Not Available";
            [phone setBackgroundColor:[UIColor clearColor]];
            [ phone setFont:[UIFont fontWithName:@"Arial-BoldMT" size:25]];
            phone.textColor = [UIColor whiteColor];
            [selectionView addSubview:phone];
        }
        else{

            UILabel *phone = [[UILabel alloc]initWithFrame:CGRectMake(130, 70, 300, 50)];
            phone.text =[[mainArray valueForKey:@"phone"] objectAtIndex:[indexPath row]];
            [phone setBackgroundColor:[UIColor clearColor]];
            [ phone setFont:[UIFont fontWithName:@"Arial-BoldMT" size:25]];
            phone.textColor = [UIColor whiteColor];
            [selectionView addSubview:phone];

        }
        if ([[[mainArray valueForKey:@"email"] objectAtIndex:[indexPath row]] isEqualToString:@"Add Email"]) {

            UILabel *email = [[UILabel alloc]initWithFrame:CGRectMake(420, 40, 350, 50)];
            email.text =@"Email Id Not Available";
            [email setBackgroundColor:[UIColor clearColor]];
            [ email setFont:[UIFont fontWithName:@"Arial-BoldMT" size:20]];
            email.textColor = [UIColor whiteColor];
            [selectionView addSubview:email];
        }
        else{

            UILabel *email = [[UILabel alloc]initWithFrame:CGRectMake(420, 40, 350, 50)];
            email.text =[[mainArray valueForKey:@"email"] objectAtIndex:[indexPath row]];
            [email setBackgroundColor:[UIColor clearColor]];
            [ email setFont:[UIFont fontWithName:@"Arial-BoldMT" size:20]];
            email.textColor = [UIColor whiteColor];
            [selectionView addSubview:email];

        }

         [[cell contentView] addSubview:selectionView];
         return cell;
    }

我面临的问题是，当我单击任何索引而不是正确的索引时，它会到达表格顶部

Answer 1

要使用索引，您的表实际上应该分为几个部分。目前您似乎要求框架滚动到指定行，然后立即滚动到第 0 节的顶部。

如果您使用performSelector在短暂延迟后请求滚动(可能看起来很糟糕)，它可能会起作用。或者，如果您从该方法返回 -1(文档不支持这种猜测)。

答案实际上是使用表中的部分并让框架按设计工作。