为啥 UITableView 是空的？

Posted 2023-03-03

【中文标题】为啥 UITableView 是空的？

【英文标题】：Why UITableView is empty?为什么 UITableView 是空的？

【发布时间】：2014-03-05 12:02:05

【问题描述】：

我想在 UITableView 中构建菜单，但我做错了什么。 我做错了什么？我得到空的 UITableView。我不知道，怎么了。也许有什么想法？ 这是我的代码： .h

#import <UIKit/UIKit.h>

@interface ViewController : UIViewController <UITableViewDelegate, UITableViewDataSource>

    IBOutlet UITableView *tblSimpleTable;
    NSMutableArray *array1;
    UIBarButtonItem *addButton;
    BOOL manyCells;
    UIView *headerView;
    UITapGestureRecognizer  *headerTapped;
    NSMutableArray *history;
    NSString *valueToSave;
    NSMutableArray      *sectionTitleArray;
    NSMutableDictionary *sectionContentDict;
    NSMutableArray      *arrayForBool;
    UITableView *table;


- (IBAction) EditTable:(id)sender;

@end

.m

#import "ViewController.h"

@interface ViewController ()

@end

@implementation ViewController

- (void)viewDidLoad

    NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
    NSMutableArray *arrayOfImages = [userDefaults objectForKey:@"tableViewDataImage"];

    NSLog(@"test: %@", arrayOfImages);

    self.view.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"news1.jpg"]];

    addButton = [[UIBarButtonItem alloc] initWithTitle:@"" style:UIBarButtonItemStyleBordered target:self action:@selector(EditTable:)];

    [super viewDidLoad];
    // Do any additional setup after loading the view, typically from a nib.

    if (!sectionTitleArray) 
        sectionTitleArray = [NSMutableArray arrayWithObjects:@"Aachen", @"Berlin", @"Düren", @"Essen", @"Münster", @"Düren", @"Essen", @"Münster", @"Münster", nil];
    
    if (!arrayForBool) 
        arrayForBool    = [NSMutableArray arrayWithObjects:[NSNumber numberWithBool:NO],
                           [NSNumber numberWithBool:NO],
                           [NSNumber numberWithBool:NO],
                           [NSNumber numberWithBool:NO],
                           [NSNumber numberWithBool:NO],
                           [NSNumber numberWithBool:NO],
                           [NSNumber numberWithBool:NO],
                           [NSNumber numberWithBool:NO],
                           [NSNumber numberWithBool:NO] , nil];
    
    if (!sectionContentDict) 
        sectionContentDict = [[NSMutableDictionary alloc] init];

        if (arrayOfImages == NULL)
        
            array1 = [NSMutableArray arrayWithObjects:@"   Fakty", @"   Sport", @"   Rozrywka", @"   Kultura", @"   Biznes", @"   deLuxe",@"   Dom",nil];
        
        else
        
            array1 = arrayOfImages;
        

        [sectionContentDict setValue:array1 forKey:[sectionTitleArray objectAtIndex:0]];
        //        NSArray *array2     = [NSArray arrayWithObjects:@"wurst 1", @"käse 2", @"keks 3", nil];
        //        [sectionContentDict setValue:array2 forKey:[sectionTitleArray objectAtIndex:1]];

        table = [[UITableView alloc]initWithFrame:CGRectMake(0.0, 0.0, self.view.frame.size.width, self.view.frame.size.height)];
        [self.view addSubview:table];

    


#pragma mark - Table View

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
    return [sectionTitleArray count];

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
    if ([[arrayForBool objectAtIndex:section] boolValue]) 
        return [[sectionContentDict valueForKey:[sectionTitleArray objectAtIndex:section]] count];
    
    return 0;


- (UIView *)tableView:(UITableView *)tableView viewForHeaderInSection:(NSInteger)section
    headerView = [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.view.frame.size.width, 50)];
    headerView.tag = section;
    headerView.backgroundColor = [UIColor clearColor];
    UILabel *headerString = [[UILabel alloc] initWithFrame:CGRectMake(30, 0, 120, 50)];
    headerString.backgroundColor = [UIColor clearColor];
    manyCells = [[arrayForBool objectAtIndex:section] boolValue];

    if (section == 0)
    
        headerString.text = @"Wiadomości";
        headerTapped   = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(sectionHeaderTapped:)];
        [headerView addGestureRecognizer:headerTapped];
        //up or down arrow depending on the bool
        UIImageView *upDownArrow        = [[UIImageView alloc] initWithImage:manyCells ? [UIImage imageNamed:@"upArrowBlack"] : [UIImage imageNamed:@"downArrowBlack"]];
        upDownArrow.autoresizingMask    = UIViewAutoresizingFlexibleLeftMargin;
        upDownArrow.frame               = CGRectMake(150, 10, 25, 25);
        upDownArrow.backgroundColor = [UIColor clearColor];
        [headerView addSubview:upDownArrow];

    
    else if (section == 1)
    
        headerString.text = @"Firmy";
        headerTapped   = [[UITapGestureRecognizer alloc] initWithTarget:self action:@selector(sectionHeaderTappedd:)];
        [headerView addGestureRecognizer:headerTapped];
    
    else if (section == 2)
    
        headerString.text = @"Imprezy";
    
    else if (section == 3)
    
        headerString.text = @"Kino";
    
    else if (section == 4)
    
        headerString.text = @"Komunikacja";
    
    else if (section == 5)
    
        headerString.text = @"Pogoda";
    
    else if (section == 6)
    
        headerString.text = @"Ogłoszenia";
    
    else if (section == 7)
    
        headerString.text = @"Poinformuj nas";
    
    else if (section == 8)
    
        headerString.text = @"Ustawienia";
    


    headerString.textAlignment = NSTextAlignmentLeft;
    headerString.textColor = [UIColor blackColor];
    [headerView addSubview:headerString];

    return headerView;


- (CGFloat)tableView:(UITableView *)tableView heightForHeaderInSection:(NSInteger)section
    return 50;


- (CGFloat)tableView:(UITableView *)tableView heightForRowAtIndexPath:(NSIndexPath *)indexPath
    //    ]if ([[arrayForBool objectAtIndex:indexPath.section] boolValue]) 
    return 44;
    //    


//- (CGFloat)tableView:(UITableView *)tableView heightForFooterInSection:(NSInteger)section
//    return 1;
//
// Customize the appearance of table view cells.
- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
    static NSString *CellIdentifier = @"Cell";

    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (cell == nil) 
        cell = [[UITableViewCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
        if ([[UIDevice currentDevice] userInterfaceIdiom] == UIUserInterfaceIdiomPhone) 
            cell.accessoryType = UITableViewCellAccessoryDisclosureIndicator;
        
    
    //    BOOL manyCells  = [[arrayForBool objectAtIndex:indexPath.section] boolValue];
    //    if (!manyCells) 
    //        cell.textLabel.text = @"click to enlarge";
    //    
    //    else
    NSArray *content = [sectionContentDict valueForKey:[sectionTitleArray objectAtIndex:indexPath.section]];
    cell.textLabel.text = [content objectAtIndex:indexPath.row];
    //    
    cell.backgroundColor = [UIColor clearColor];

    return cell;


- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
    [tableView deselectRowAtIndexPath:indexPath animated:YES];
//    DetailViewController *dvc;
//    if ([UIDevice currentDevice].userInterfaceIdiom == UIUserInterfaceIdiomPhone) 
//        dvc = [[DetailViewController alloc] initWithNibName:@"DetailViewController_iPhone"  bundle:[NSBundle mainBundle]];
//    else
//        dvc = [[DetailViewController alloc] initWithNibName:@"DetailViewController_iPad"  bundle:[NSBundle mainBundle]];
//    
//    dvc.title        = [sectionTitleArray objectAtIndex:indexPath.section];
//    dvc.detailItem   = [[sectionContentDict valueForKey:[sectionTitleArray objectAtIndex:indexPath.section]] objectAtIndex:indexPath.row];
//    [self.navigationController pushViewController:dvc animated:YES];



#pragma mark - gesture tapped
- (void)sectionHeaderTapped:(UITapGestureRecognizer *)gestureRecognizer

    if (manyCells)
    
        self.navigationItem.leftBarButtonItem = nil;
        [super setEditing:NO animated:NO];
        [tblSimpleTable setEditing:NO animated:NO];
        [tblSimpleTable reloadData];
    
    else
    

        [self.navigationItem setLeftBarButtonItem:addButton];
        [self.navigationItem.leftBarButtonItem setTitle:@"Edycja"];
        [self.navigationItem.leftBarButtonItem setStyle:UIBarButtonItemStylePlain];
        [super setEditing:NO animated:NO];
        [tblSimpleTable setEditing:NO animated:NO];
        [tblSimpleTable reloadData];
    


    NSIndexPath *indexPath = [NSIndexPath indexPathForRow:0 inSection:gestureRecognizer.view.tag];
    if (indexPath.row == 0) 


        BOOL collapsed  = [[arrayForBool objectAtIndex:indexPath.section] boolValue];
        collapsed       = !collapsed;
        [arrayForBool replaceObjectAtIndex:indexPath.section withObject:[NSNumber numberWithBool:collapsed]];

        //reload specific section animated
        NSRange range   = NSMakeRange(indexPath.section, 1);
        NSIndexSet *sectionToReload = [NSIndexSet indexSetWithIndexesInRange:range];
        [table reloadSections:sectionToReload withRowAnimation:UITableViewRowAnimationFade];
    


- (IBAction) EditTable:(id)sender
    NSIndexPath *indexPath = [NSIndexPath indexPathForRow:0 inSection:0];
    [table scrollToRowAtIndexPath:indexPath
                          atScrollPosition:UITableViewScrollPositionTop
                                  animated:YES];

    if(self.editing)
    
        table.scrollEnabled = YES;
        [super setEditing:NO animated:NO];
        [tblSimpleTable setEditing:NO animated:NO];
        [tblSimpleTable reloadData];
        [self.navigationItem.leftBarButtonItem setTitle:@"Edycja"];
        [self.navigationItem.leftBarButtonItem setStyle:UIBarButtonItemStylePlain];

    
    else
    
        table.scrollEnabled = NO;
        [super setEditing:YES animated:YES];
        [tblSimpleTable setEditing:YES animated:YES];
        [tblSimpleTable reloadData];
        [self.navigationItem.leftBarButtonItem setTitle:@"Gotowe"];
        [self.navigationItem.leftBarButtonItem setStyle:UIBarButtonItemStyleDone];
    


// The editing style for a row is the kind of button displayed to the left of the cell when in editing mode.
- (UITableViewCellEditingStyle)tableView:(UITableView *)aTableView editingStyleForRowAtIndexPath:(NSIndexPath *)indexPath 
    return UITableViewCellEditingStyleNone;


- (BOOL)tableView:(UITableView *)tableview shouldIndentWhileEditingRowAtIndexPath:(NSIndexPath *)indexPath 
    return NO;


#pragma mark Row reordering
// Determine whether a given row is eligible for reordering or not.
- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath 
    return YES;

// Process the row move. This means updating the data model to correct the item indices.
- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath
      toIndexPath:(NSIndexPath *)toIndexPath 

    NSUserDefaults *userDefaults = [NSUserDefaults standardUserDefaults];
    NSArray *arrayOfImages = [userDefaults objectForKey:@"tableViewDataImage"];

    NSLog(@"tablicansuser: %@", arrayOfImages);

    NSString *item = [array1 objectAtIndex:fromIndexPath.row];
    [array1 removeObject:item];
    [array1 insertObject:item atIndex:toIndexPath.row];
    NSLog(@"tablica: %@", array1);

    [userDefaults setObject:array1 forKey:@"tableViewDataImage"];
    [userDefaults synchronize];



- (NSIndexPath *)tableView:(UITableView *)tableView targetIndexPathForMoveFromRowAtIndexPath:(NSIndexPath *)sourceIndexPath toProposedIndexPath:(NSIndexPath *)proposedDestinationIndexPath

    if( sourceIndexPath.section != proposedDestinationIndexPath.section )
    
        return sourceIndexPath;
    
    else
    
        return proposedDestinationIndexPath;
    


- (void)sectionHeaderTappedd:(UITapGestureRecognizer *)gestureRecognizer

//    DetailViewController *dvc;
//    dvc = [[DetailViewController alloc] initWithNibName:@"DetailViewController_iPhone"  bundle:[NSBundle mainBundle]];
//    [self.navigationController pushViewController:dvc animated:YES];


@end

帮帮我:)

【问题讨论】：

你给[table reloadData]打过电话吗？？是否调用了您的 dataSource 方法？

您忘记设置table 的delegate 和dataSource。然后检查您的numberOfRowsInSection 是否被调用以及从那里返回什么值？

对于任何 NSMutableArray，使用 [[NSMutableArray alloc] initWitharrayWithObj...

设置UITableview的table view delegate和datasource

在哪里写 [table reloadData]？

【参考方案1】：

写入h文件

       UITableViewDelegate,UITableViewDataSource

并在 .m 文件中

       table = [[UITableView alloc]initWithFrame:CGRectMake(0.0, 0.0, self.view.frame.size.width, self.view.frame.size.height)];
       table.Delegate=self;
       table.DataSource=self;

    [self.view addSubview:table];

【讨论】：

嘿，您在 .h 文件中声明了两个 TableView 那么您要在哪个表上显示数据.....

【参考方案2】：

你必须在viewDidload方法中设置tableview委托方法

tblView.delegate = self;
tblView.dataSource = self;

还有一件事，你必须在头文件中设置UITableViewDataSource, UITableViewDelegate。