Select one row in each section of UITableView ios?

问题

Scenario:

I have made 2 sections in one UITableView and the user needs to select a row in each section as shown in the screenshot below.

Expected Outcome: 1. User should be able to select a row in each section

Outcome right now: 1. After I have selected row in one section, and then when I select the row in second section, the first selection disappears.

Here is my code:

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    // Uncheck the previous checked row

    long sec=indexPath.section;
     if(sec==0){
    if(self->checkedIndexPath)
    {
        UITableViewCell* uncheckCell = [tableView
                                        cellForRowAtIndexPath:self->checkedIndexPath];
        uncheckCell.accessoryType = UITableViewCellAccessoryNone;
    }
    if([self->checkedIndexPath isEqual:indexPath])
    {
        self->checkedIndexPath = nil;
    }
    else
    {
        UITableViewCell* cell = [tableView cellForRowAtIndexPath:indexPath];
        cell.accessoryType = UITableViewCellAccessoryCheckmark;
        self->checkedIndexPath = indexPath;
    }}

    if(sec==1){

        if(self->checkedIndexPath)
        {
            UITableViewCell* uncheckCell = [tableView
                                            cellForRowAtIndexPath:self->checkedIndexPath];
            uncheckCell.accessoryType = UITableViewCellAccessoryNone;
        }
        if([self->checkedIndexPath isEqual:indexPath])
        {
            self->checkedIndexPath = nil;
        }
        else
        {
            UITableViewCell* cell = [tableView cellForRowAtIndexPath:indexPath];
            cell.accessoryType = UITableViewCellAccessoryCheckmark;
            self->checkedIndexPath = indexPath;
        }

    }

}

Help is appreciated.

回答1:

This is the simplest way. Finally i found a solution. It works for me, hope it will work for you. declare these

@interface ViewController ()
{
    int selectedsection;
    NSMutableArray *selectedindex;

}

Replace didSelectRowAtIndexPath as follows:

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath {
    // Uncheck the previous checked row

    NSIndexPath *selectedIndexPath = [tableView indexPathForSelectedRow];

        if(self.checkedIndexPath)

        {

            for (int i=0; i<[selectedindex count]; i++) {

                NSIndexPath *temp= [selectedindex objectAtIndex:i];
                if (temp.section==selectedIndexPath.section) {
                    UITableViewCell* uncheckCell = [tableView
                                                    cellForRowAtIndexPath:temp];
                    uncheckCell.accessoryType = UITableViewCellAccessoryNone;

                }
            }

            NSInteger numb= [tableView numberOfRowsInSection:selectedIndexPath.section];

            if (selectedsection==selectedIndexPath.section) {


            UITableViewCell* uncheckCell = [tableView
                                            cellForRowAtIndexPath:self.checkedIndexPath];
            uncheckCell.accessoryType = UITableViewCellAccessoryNone;

            }
        }



        if([self.checkedIndexPath isEqual:indexPath])
        {
            for (int i=0; i<[selectedindex count]; i++) {

                NSIndexPath *temp= [selectedindex objectAtIndex:i];
                if (temp.section==selectedIndexPath.section) {
                    UITableViewCell* uncheckCell = [tableView
                                                    cellForRowAtIndexPath:temp];
                    uncheckCell.accessoryType = UITableViewCellAccessoryNone;

                }
            }


           self.checkedIndexPath = nil;
        }
        else
        {
            for (int i=0; i<[selectedindex count]; i++) {

                NSIndexPath *temp= [selectedindex objectAtIndex:i];
                if (temp.section==selectedIndexPath.section) {
                    UITableViewCell* uncheckCell = [tableView
                                                    cellForRowAtIndexPath:temp];
                    uncheckCell.accessoryType = UITableViewCellAccessoryNone;

                }
            }

            UITableViewCell* cell = [tableView cellForRowAtIndexPath:indexPath];
            cell.accessoryType = UITableViewCellAccessoryCheckmark;
            self.checkedIndexPath = indexPath;
            [selectedindex addObject:indexPath];
            selectedsection=indexPath.section;

            NSLog(@"check");
        }






}

回答2:

You can enable the multiple selection in the tableview:

self.tableView.allowsMultipleSelection = YES;

回答3:

I wrote a sample code where a compound datasource holds datasource objects for each section. Sounds complicated but actually provides an easy to extend architecture. And keeps your view controller small.

The advantages of this approach:

Small ViewController
ViewController set ups view and handles user interaction — as it should be in MVC
Reusable datasources
by using different datasources per section easy to customize cells for each section

the base datasource architecture

This provides easy extension and is simple to reuse.

@import UIKit;

@interface ComoundTableViewDataSource : NSObject
@property (nonatomic,strong, readonly) NSMutableDictionary *internalDictionary;


-(void) setDataSource:(id<UITableViewDataSource>)dataSource forSection:(NSUInteger)section;
-(instancetype)initWithTableView:(UITableView *)tableView;
@end

#import "ComoundTableViewDataSource.h"


@interface ComoundTableViewDataSource () <UITableViewDataSource>
@property (nonatomic,strong, readwrite) NSMutableDictionary *internalDictionary;
@property (nonatomic, weak) UITableView *tableView;
@end

@implementation ComoundTableViewDataSource
-(instancetype)initWithTableView:(UITableView *)tableView
{
    self = [super init];
    if (self) {
        _tableView = tableView;
        tableView.dataSource = self;
        _internalDictionary = [@{} mutableCopy];
        [self.tableView registerClass:[UITableViewCell class] forCellReuseIdentifier:@"Cell"];

    }
    return self;
}

-(void)setDataSource:(id<UITableViewDataSource>)dataSource forSection:(NSUInteger)section
{
    self.internalDictionary[@(section)] = dataSource;
    [self.tableView reloadData];

}

-(NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    return [[self.internalDictionary allKeys] count];
}

-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    id<UITableViewDataSource> sectionDataSource = self.internalDictionary[@(section)];
    return [sectionDataSource tableView:tableView numberOfRowsInSection:section];
}

-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    id<UITableViewDataSource> sectionDataSource = self.internalDictionary[@(indexPath.section)];
    return [sectionDataSource tableView:tableView cellForRowAtIndexPath:indexPath];

}


-(NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section
{
    id<UITableViewDataSource> sectionDataSource = self.internalDictionary[@(section)];
    return [sectionDataSource tableView:tableView titleForHeaderInSection:section];
}
@end

@import UIKit;

@interface SingleSectionDataSource : NSObject <UITableViewDataSource>
@property (nonatomic, strong, readonly) NSArray *array;
@property (nonatomic, strong, readonly) UITableView *tableView;

- (instancetype)initWithArray:(NSArray *)array;
@end

#import "SingleSectionDataSource.h"

@interface SingleSectionDataSource ()
@property (nonatomic, strong, readwrite) NSArray *array;
@property (nonatomic, strong, readwrite) UITableView *tableView;

@end

@implementation SingleSectionDataSource

- (instancetype)initWithArray:(NSArray *)array
{
    self = [super init];
    if (self) {
        self.array = array;
    }
    return self;
}
-(NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    return 1;
}

-(NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    self.tableView = tableView;
    return self.array.count;
}

-(UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:@"Cell" forIndexPath:indexPath];
    cell.textLabel.text = self.array[indexPath.row];
    return cell;
}

-(NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section
{
    return [@(section) stringValue];
}

@end

the selection datasource architecture

We extend the classes from above to allow one selection per section

#import "ComoundTableViewDataSource.h"

@interface OnSelectionPerSectionComoundTableViewDataSource : ComoundTableViewDataSource
-(void)selectedCellAtIndexPath:(NSIndexPath *)indexPath;

@end

#import "OnSelectionPerSectionComoundTableViewDataSource.h"
#import "SingleSelectionSingleSectionDataSource.h"

@implementation OnSelectionPerSectionComoundTableViewDataSource


-(instancetype)initWithTableView:(UITableView *)tableView
{
    self = [super initWithTableView:tableView];
    if(self){
        [tableView setAllowsMultipleSelection:YES];
    }
    return self;
}

-(void)selectedCellAtIndexPath:(NSIndexPath *)indexPath
{
    SingleSelectionSingleSectionDataSource *sectionDataSource = self.internalDictionary[@(indexPath.section)];
    [sectionDataSource selectedCellAtIndexPath:indexPath];
}
@end

View Controller Implementation

As promised, a very slim view controller:

@interface ViewController () <UITableViewDelegate>
@property (weak, nonatomic) IBOutlet UITableView *tableView;
@property (nonatomic, strong) OnSelectionPerSectionComoundTableViewDataSource *tableViewDataSource;

@end

@implementation ViewController

- (void)viewDidLoad {
    [super viewDidLoad];

    self.tableViewDataSource = [[OnSelectionPerSectionComoundTableViewDataSource alloc] initWithTableView:self.tableView];
    self.tableView.delegate = self;
    [self.tableViewDataSource setDataSource:[[SingleSelectionSingleSectionDataSource alloc] initWithArray:@[@"Hallo", @"Welt"]] forSection:0];
    [self.tableViewDataSource setDataSource:[[SingleSelectionSingleSectionDataSource alloc] initWithArray:@[@"Hello", @"World", @"!"]] forSection:1];
    [self.tableViewDataSource setDataSource:[[SingleSelectionSingleSectionDataSource alloc] initWithArray:@[@"Hola", @"Mundo", @"!", @"¿Que tal?"]] forSection:2];
}

-(void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    [self.tableViewDataSource selectedCellAtIndexPath:indexPath];
}
@end

You will want to add methods to the datasources to get the selected rows.

get the example: https://github.com/vikingosegundo/CompoundDatasourceExample

Note This code has a cell reuse issue. It is fixed on GitHub.

来源：https://stackoverflow.com/questions/27838390/select-one-row-in-each-section-of-uitableview-ios

标签

ios

objective-c

uitableview

didselectrowatindexpath