在 iOS 中创建可编辑的表格视图？

Question

我正在尝试使用 .xib 文件在 iOS 中创建一个可编辑的表格视图。

我的代码如下所示：

viewController.h

#import <UIKit/UIKit.h>

@interface ViewController : UITableViewController

@property (nonatomic, strong) NSMutableArray *notes;

@end

viewController.m

#import "ViewController.h"
#import "Note.h"

@interface ViewController ()

@end

@implementation ViewController

- (id)initWithStyle:(UITableViewStyle)style
{
    self = [super initWithStyle:style];
    if (self) {
        // Custom initialization
    }
    return self;
}

- (void)viewDidLoad
{
    [super viewDidLoad];

    [self setEditing:NO animated:NO];
}

- (void)viewWillAppear:(BOOL)animated{

    self.notes = [[Note savedNotes]mutableCopy];
    [self.tableView reloadData];
}

- (void)didReceiveMemoryWarning
{
    [super didReceiveMemoryWarning];
    // Dispose of any resources that can be recreated.
}

#pragma mark - Button Events

- (void)setEditing:(BOOL)editing animated:(BOOL)animated
{
    [super setEditing:editing animated:animated];

    if (editing) {
        UIBarButtonItem *cancelButton = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemCancel target:self action:@selector(cancelButtonPressed:)];
        self.navigationItem.leftBarButtonItem = cancelButton;

        UIBarButtonItem *doneButton = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemDone target:self action:@selector(rightButtonPressed:)];

        self.navigationItem.rightBarButtonItem = doneButton;

    }else{
        self.navigationItem.leftBarButtonItem = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemAdd
                                                                                             target:self
                                                                                             action:@selector(addNoteButtonPressed:)];

        UIBarButtonItem *editButton = [[UIBarButtonItem alloc]initWithBarButtonSystemItem:UIBarButtonSystemItemEdit
                                                                                   target:self
                                                                                   action:@selector(rightButtonPressed:)];

        self.navigationItem.rightBarButtonItem = editButton;
    }

}

- (void)rightButtonPressed:(id)sender{

    [self setEditing:!self.isEditing animated:YES];
}

- (void)cancelButtonPressed:(id)sender{
    [self setEditing:!self.isEditing animated:YES];
}

- (void)addNoteButtonPressed:(id)sender{
    //ATTViewController *viewController = [self.storyboard instantiateViewControllerWithIdentifier:@"ATTViewController"];
    //[self.navigationController pushViewController:viewController animated:YES];
}

#pragma mark - Table view data source

- (NSInteger)numberOfSectionsInTableView:(UITableView *)tableView
{
    // Return the number of sections.
    return 1;
}

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    // Return the number of rows in the section.
    return [self.notes count];
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"Cell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];

    // Configure the cell...

    Note *note = self.notes[indexPath.row];

    cell.textLabel.text = note.name;
    cell.detailTextLabel.text = note.event;

    return cell;
}


// Override to support conditional editing of the table view.
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
{
    // Return NO if you do not want the specified item to be editable.
    return YES;
}

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


// Override to support editing the table view.
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
    if (editingStyle == UITableViewCellEditingStyleDelete) {
        // Delete the row from the data source
        Note *note = self.notes[indexPath.row];
        [note remove];
        [self.notes removeObjectAtIndex:indexPath.row];
        [tableView deleteRowsAtIndexPaths:@[indexPath]
                         withRowAnimation:UITableViewRowAnimationFade];
    }
    else if (editingStyle == UITableViewCellEditingStyleInsert) {
        // Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view
    }
}


/*
 // Override to support rearranging the table view.
 - (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath
 {
 }
 */

/*
 // Override to support conditional rearranging of the table view.
 - (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath
 {
 // Return NO if you do not want the item to be re-orderable.
 return YES;
 }
 */

#pragma mark - Table view delegate

- (void)tableView:(UITableView *)tableView didSelectRowAtIndexPath:(NSIndexPath *)indexPath
{
    // Navigation logic may go here. Create and push another view controller.
    /*
     <#DetailViewController#> *detailViewController = [[<#DetailViewController#> alloc] initWithNibName:@"<#Nib name#>" bundle:nil];
     // ...
     // Pass the selected object to the new view controller.
     [self.navigationController pushViewController:detailViewController animated:YES];
     */
    [tableView deselectRowAtIndexPath:indexPath animated:YES];
}

@end

在 .xib 的身份检查器中，我将类从 UIView 更改为 UITableView。

我将视图与数据源和/或委托连接（我尝试了所有组合）。

但是，我在电话上总是一无所获。我没有得到表格视图，只是一个空的灰色屏幕。

任何想法我做错了什么？上面的代码在一个使用故事板的项目中工作，现在我正试图让它与 .xib 文件一起工作。

截图：

Answer 1

我建议查看免费的 Sensible TableView 框架。将自动处理显示您的数组并代表您处理所有插入/删除。为我节省了大量时间。

Answer 2

经过一些工作，我能够做到并决定将其公开：

Code on GitHub

我正在学习如何做到这一点，但我想支持移动、删除和添加。

一些示例仅显示最后一行的添加按钮，而其他示例仅显示移动/删除。

对我来说棘手的一点是同时支持 3 个。

希望对你有帮助。

代码如下：

EditTVC.h

#import <UIKit/UIKit.h>

@interface EditTVC : UITableViewController

@end

EditTVC.m

//
//  EditTVC.m
//  editTableViewTest
//

#import "EditTVC.h"

@interface EditTVC ()

@property (nonatomic) NSMutableArray *myItems;

@end

@implementation EditTVC

@synthesize myItems;

- (void)viewDidLoad
{
    [super viewDidLoad];

    myItems = [[NSMutableArray alloc] init];

    for (int i=0; i<5; i++)
    {
        [myItems addObject:[NSString stringWithFormat:@"Hey %d",i]];
    }

    NSLog(@"%@",myItems);


    // Display an Edit button in the navigation bar for this view controller.
    self.navigationItem.rightBarButtonItem = self.editButtonItem;
}

#pragma mark - Table view data source


- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section
{
    // Return the number of rows in the section.

    if (self.editing) {
        return myItems.count +1;
    }

    return myItems.count;
}

-(UITableViewCellEditingStyle)tableView:(UITableView *)tableView editingStyleForRowAtIndexPath:(NSIndexPath *)indexPath {
    if (indexPath.row == myItems.count)
        return UITableViewCellEditingStyleInsert;
    else
        return UITableViewCellEditingStyleDelete;
}

- (BOOL)tableView:(UITableView *)tableView canMoveRowAtIndexPath:(NSIndexPath *)indexPath
{
    // Return NO if you do not want the item to be re-orderable.
    if (indexPath.row == myItems.count)
        return NO;
    else
        return YES;
}

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath
{
    static NSString *CellIdentifier = @"MyCell";
    UITableViewCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier forIndexPath:indexPath];

    // Configure the cell...

    if (self.editing && indexPath.row == myItems.count)
    {
        cell.textLabel.text = @"Add ...";
    }
    else
    {
        cell.textLabel.text = myItems[indexPath.row];
    }

    return cell;
}

-(void)setEditing:(BOOL)editing animated:(BOOL)animated {

    [super setEditing:editing animated:animated];

    if(editing)
    {
        //edit mode
    }

    else
    {
        //non-edit mode
    }

    [self.tableView reloadData];
}

// Override to support editing the table view.
- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{
    if (editingStyle == UITableViewCellEditingStyleDelete)
    {
        // Delete the row from the data source
        [myItems removeObjectAtIndex:indexPath.row];

        [tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade];
    }   
    else if (editingStyle == UITableViewCellEditingStyleInsert)
    {
        // Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view
        [myItems insertObject:[NSString stringWithFormat:@"Added %ld",(long)indexPath.row] atIndex:indexPath.row];
        [tableView insertRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationFade];
    }
    NSLog(@"%@",myItems);
}

// Override to support rearranging the table view.
- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath
{
    if (toIndexPath.row == myItems.count) //we only check the toIndexPath because we made the AddCell not to respond to move events
    {
        id tmp = [myItems objectAtIndex:fromIndexPath.row];
        [myItems removeObjectAtIndex:fromIndexPath.row];
        [myItems insertObject:tmp atIndex:toIndexPath.row-1]; //to keep it in valid range for the NSMutableArray

        [self.tableView reloadData];
    }

    else
    {
        id tmp = [myItems objectAtIndex:fromIndexPath.row];
        [myItems removeObjectAtIndex:fromIndexPath.row];
        [myItems insertObject:tmp atIndex:toIndexPath.row];
    }

    NSLog(@"%@",myItems);
}



@end

Answer 3

将至少一项添加到您的数组中，否则将不显示任何内容（当前您的 cellForRowAtIndexPath 正在返回 0）。另外，请确保 tableView 的委托已分配给您在 IB 中的类。