如何从UITableView中删除一行

时间：2010-12-21 09:46:00

标签： iphone objective-c uitableview

我正在尝试从表格视图中删除一行，但到目前为止还没有成功。我一直收到这个错误：

  

“因未捕获的异常而终止应用   'NSInternalInconsistencyException'，原因：'无效更新：无效   第0节中的行数。包含在中的行数   更新后的现有部分（5）必须等于数量   更新前的该部分中包含的行（5），加号或减号   从该部分插入或删除的行数（插入0，   1删除）。''我用来填充表视图的数组是   在该类中声明，我也从我的数组中获取我的对象   sqlite db。

我用来尝试删除行的代码如下。

- (void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath {

if (editingStyle == UITableViewCellEditingStyleDelete) {
    // Delete the row from the data source

    [categoryArray objectAtIndex:indexPath.row];
    [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:YES];

}   
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
}   
}

现在我希望得到回答的问题：

- 如何正确删除行？

- 我是否会删除该行，如果它只是在tableView中留下的那一行？

- 我可以将方法中使用的tableView更改为我声明的UITableView 我的.h文件？

非常感谢。

修改

-Full .m代码

#import "DeleteCategoryTableView.h"
#import "KeyCryptAppAppDelegate.h"


@implementation DeleteCategoryTableView
@synthesize categoryArray;

#pragma mark -
#pragma mark Initialization

-(void) initializeCategoryArray {

sqlite3 *db= [KeyCryptAppAppDelegate getNewDBConnection];
KeyCryptAppAppDelegate *appDelegate = (KeyCryptAppAppDelegate *)[[UIApplication sharedApplication] delegate];

const char *sql = [[NSString stringWithFormat:(@"Select Category from Categories;")]cString];


sqlite3_stmt *compiledStatement;



if (sqlite3_prepare_v2(db, sql, -1, &compiledStatement, NULL)==SQLITE_OK)
{
    while(sqlite3_step(compiledStatement) == SQLITE_ROW)
        [categoryArray addObject:[NSString stringWithUTF8String:(char*) sqlite3_column_text(compiledStatement, 0)]];

}
else {
    NSAssert1(0,@"Error preparing statement", sqlite3_errmsg(db));
}
sqlite3_finalize(compiledStatement);
}
/*
- (id)initWithStyle:(UITableViewStyle)style {
// Override initWithStyle: if you create the controller programmatically and want to perform customization that is not appropriate for viewDidLoad.
if ((self = [super initWithStyle:style])) {
}
return self;
}
*/
#pragma mark -
#pragma mark View lifecycle
- (void)viewDidLoad {
self.title = NSLocalizedString(@"Delete Categories",@"Delete your Categories");
categoryArray = [[NSMutableArray alloc]init];
[self initializeCategoryArray];
[super viewDidLoad];

// Uncomment the following line to display an Edit button in the navigation bar for this view controller.
self.navigationItem.rightBarButtonItem = self.editButtonItem;
}
/*
- (void)viewWillAppear:(BOOL)animated {
[super viewWillAppear:animated];
}
*/
/*
- (void)viewDidAppear:(BOOL)animated {
[super viewDidAppear:animated];
}
*/
/*
- (void)viewWillDisappear:(BOOL)animated {
[super viewWillDisappear:animated];
}
*/
/*
- (void)viewDidDisappear:(BOOL)animated {
[super viewDidDisappear:animated];
}
*/
/*
// Override to allow orientations other than the default portrait orientation.
- (BOOL)shouldAutorotateToInterfaceOrientation:(UIInterfaceOrientation)interfaceOrientation {
// Return YES for supported orientations
return (interfaceOrientation == UIInterfaceOrientationPortrait);
}
*/


#pragma mark -
#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.categoryArray count];
}


// 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] autorelease];
}

// Configure the cell...
NSUInteger row = [indexPath row];
cell.text = [categoryArray objectAtIndex:row];
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;
}
*/
// 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

    [categoryArray removeObjectAtIndex:indexPath.row];
    [tableView deleteRowsAtIndexPaths:[NSArray arrayWithObject:indexPath] withRowAnimation:YES];
    [deleteCategoryTable reloadData];

    NSString *selectedCategory = [categoryArray objectAtIndex:indexPath.row];

    sqlite3 *db= [KeyCryptAppAppDelegate getNewDBConnection];
    KeyCryptAppAppDelegate *appDelegate = (KeyCryptAppAppDelegate *)[[UIApplication sharedApplication] delegate];
    const char *sql = [[NSString stringWithFormat:@"Delete from Categories where Category = '%@';", selectedCategory]cString];

    sqlite3_stmt *compiledStatement;


    if (sqlite3_prepare_v2(db, sql, -1, &compiledStatement, NULL)==SQLITE_OK)
    {
        sqlite3_exec(db,sql,NULL,NULL,NULL);

    }
    else {
        NSAssert1(0,@"Error preparing statement", sqlite3_errmsg(db));
    }
    sqlite3_finalize(compiledStatement);
}



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 -
#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];
 [detailViewController release];
 */
}
#pragma mark -
#pragma mark Memory management

- (void)didReceiveMemoryWarning {
// Releases the view if it doesn't have a superview.
[super didReceiveMemoryWarning];

// Relinquish ownership any cached data, images, etc that aren't in use.
}

- (void)viewDidUnload {
// Relinquish ownership of anything that can be recreated in viewDidLoad or on demand.
// For example: self.myOutlet = nil;
}


- (void)dealloc {
[super dealloc];
}


@end

5 个答案:

答案 0 :(得分：21)

1）删除的问题是

[categoryArray removeObjectAtIndex:indexPath.row];

也可以从db中删除它。

删除行后，使用[tableView reloadData]

重新加载tableView

2）如果它是唯一的一个项目

没有问题

修改

这是问题

[categoryArray removeObjectAtIndex:indexPath.row];
NSString *selectedCategory = [categoryArray objectAtIndex:indexPath.row];

在同一个indexPath.row访问值之后，你已经从数组中删除了indexPath.row的值，显然它只会删除下一个值.. :)

所以把那个

NSString *selectedCategory = [categoryArray objectAtIndex:indexPath.row]

[categoryArray removeObjectAtIndex:indexPath.row];之前的行

答案 1 :(得分：7)

这是您需要做的 ALL 。它归结为很好地实现了一种方法。

Swift 2 

func tableView(_ tableView: UITableView, commit editingStyle: UITableViewCellEditingStyle, forRowAt indexPath: IndexPath) {
    if editingStyle == .delete {

        //1. remove data from model
        data.remove(at: indexPath.row)

        //2. remove row from view
        tableView.deleteRows(at: [indexPath as IndexPath], with: .fade)

        //3. custom method to update your view after removing
        updateView()
    }
}

Swift 3 

{{1}}

答案 2 :(得分：1)

您的代码很好，期望withRowAnimation:不期望BOOL而是UITableViewRowAnimation成员。例如。 UITableViewRowAnimationRight让它滑到桌子的右侧。

另外：你只是从数组中获取对象，你必须删除它！如果是可变数组，则可以使用[categoryArray removeObjectAtIndex:indexpath.row]

答案 3 :(得分：1)

为此目的不要尝试删除行尝试从数组或数据源中删除（如果数组正在从数据库中准备）然后尝试通过简单地调用数据库函数来重新加载数组。

然后

[table reloadData].

这是正确的做法。

答案 4 :(得分：0)

从控制台中了解问题所在。

你有一个方法numberOfRowsInSection ...让我们说它设置为return 5;。

当你从表格视图中删除一行时，你还需要更新这个方法......所以它会从那个方法中找你return 4;。

基本上，您需要确保表格视图中的行数比删除行之前少一行。

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