ios - 带有固定部分标题的 UITableView

Question

您好，我正在阅读 UITableView 的默认行为是在滚动部分时将部分标题行固定到表格的顶部，直到下一个部分将上一个部分行推到视野之外。

我有一个 UITableView在 UIViewController 内而这似乎并非如此。

这只是 UITableViewController 的默认行为吗？ ?

这里有一些基于我所拥有的简化代码。我将显示 UIController接口(interface)和我为创建 TableView 而实现的每个 TableView 方法。我有一个辅助数据源类，它可以帮助我索引我的对象以用于表。

    @interface MyUIViewController ()<UITableViewDelegate, UITableViewDataSource>
        @property (nonatomic, readonly) UITableView *myTableView;
        @property (nonatomic, readonly) MyCustomHelperDataSource *helperDataSource;
    @end

    //when section data is set, get details for each section and reload table on success
    - (void)setSectionData:(NSArray *)sections {
        super.sectionData = sections; //this array drives the sections

        //get additional data for section details
        [[RestKitService sharedClient] getSectionDetailsForSection:someId 
        success:^(RKObjectRequestOperation *operation, RKMappingResult *details) {
            NSLog(@"Got section details data");
            _helperDataSource = [[MyCustomHelperDataSource alloc] initWithSections:sections andDetails:details.array];
            [myTableView reloadData];
        } failure:^(RKObjectRequestOperation *operation, NSError *error) {
            NSLog(@"Failed getting section details");
        }];
    }

    #pragma mark <UITableViewDataSource, UITableViewDelegate>

    - (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView {
        if (!_helperDataSource) return 0;
        return [_helperDataSource countSectionsWithDetails]; //number of section that have details rows, ignore any empty sections
    }

    - (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
        //get the section object for the current section int
        SectionObject *section = [_helperDataSource sectionObjectForSection:section];
        //return the number of details rows for the section object at this section
        return [_helperDataSource countOfSectionDetails:section.sectionId];
    }

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

        UITableViewCell * cell;

        NSString *CellIdentifier = @"SectionDetailCell";

        cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
        if (cell == nil) {
            initWithStyle:UITableViewCellStyleValue1 reuseIdentifier:CellIdentifier];
            cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleSubtitle reuseIdentifier:CellIdentifier];
            cell.textLabel.font = [UIFont systemFontOfSize:12.0f];
        }

        //get the detail object for this section
        SectionObject *section = [_helperDataSource sectionObjectForSection:indexPath.section]; 

        NSArray* detailsForSection = [_helperDataSource detailsForSection:section.sectionId] ;
        SectionDetail *sd = (SectionDetail*)[detailsForSection objectAtIndex:indexPath.row];

        cell.textLabel.text = sd.displayText;
        cell.detailTextLabel.text = sd.subText;
        cell.detailTextLabel.textColor = [UIColor blueTextColor];

        return cell;
    }

- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath {
    return 50.0f;
}

- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section {
    return 30.0f;
}

- (NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger) section {
    //get the section object for the current section
    SectionObject *section = [_helperDataSource sectionObjectForSection:section]; 

    NSString *title = @"%@ (%d)";

    return [NSString stringWithFormat:title, section.name, [_helperDataSource countOfSectionDetails:section.sectionId]];
}

- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section {
    UIView *header = [[UIView alloc] initWithFrame:CGRectMake(0, 0, 260, 0)];
    header.autoresizingMask = UIViewAutoresizingFlexibleWidth;

    header.backgroundColor = [UIColor darkBackgroundColor];

    SSLabel *label = [[SSLabel alloc] initWithFrame:CGRectMake(3, 3, 260, 24)];
    label.font = [UIFont boldSystemFontOfSize:10.0f];
    label.verticalTextAlignment = SSLabelVerticalTextAlignmentMiddle;
    label.backgroundColor = [UIColor clearColor];
    label.text = [self tableView:tableView titleForHeaderInSection:section];
    label.textColor = [UIColor whiteColor];
    label.shadowColor = [UIColor darkGrayColor];
    label.shadowOffset = CGSizeMake(1.0, 1.0);
    [header addSubview:label];

    return header;
}

Answer 1

仅当表格的 UITableViewStyle 属性设置为 UITableViewStylePlain 时，标题才会保持固定( float )。

如果您将其设置为 UITableViewStyleGrouped，标题将与单元格一起向上滚动(不会 float )。