在 NSMutableArray 之间移动 objects 时出错

Question

在我的 iOS 应用程序中，我有一个 table 视图，它有 2 个部分/2 个数组。我正在尝试将一个 object 从一个 array/section 移动到另一个 array/section。现在第 0 节称为 followedArray，第 1 节称为 dataArray，dataArray 存储构成每个单元格的所有数据。因此，当用户单击我设置的名为 Follow 的按钮时，它应该获取该单元格并将其从 dataArray/Section 1 中删除并将其插入到 followedArray/Section 0 中。但是当我尝试这样做时，我得到一个错误这么说。

错误信息

*** Assertion failure in -[UITableView _endCellAnimationsWithContext:], /BuildRoot/Library/Caches/com.apple.xbs/Sources/UIKit/UIKit-3599.6/UITableView.m:1396

*** Terminating app due to uncaught exception 'NSInternalInconsistencyException', reason: 'attempt to insert row 0 into section 0, but there are only 0 rows in section 0 after the update'

代码：

TableView

- (UITableViewCell *)tableView:(UITableView *)tableView cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    
    static NSString *CellIdentifier = @"Cell";
    CustomCell *cell = [tableView dequeueReusableCellWithIdentifier:CellIdentifier];
    if (!cell) {
        cell = [[CustomCell alloc] initWithStyle:UITableViewCellStyleDefault reuseIdentifier:CellIdentifier];
    }
    
    // Configuring the cell
    Data * dataObject;
    if (!isFiltered) {
        
        if (indexPath.section == 0) {
            dataObject = [followedArray objectAtIndex:indexPath.row];
        }
        else if (indexPath.section == 1) {
            dataObject = [dataArray objectAtIndex:indexPath.row];
        }
    }
    else {
        dataObject = [filteredArray objectAtIndex:indexPath.row];
    }
    
    // Loading Button
    cell.followButton.tag = indexPath.row;
    [cell.followButton addTarget:self action:@selector(followButtonClick:) forControlEvents:UIControlEventTouchUpInside];
    cell.followButton.hidden = NO;
    
    return cell;
}

小节Headers

-(NSString *)tableView:(UITableView *)tableView titleForHeaderInSection:(NSInteger)section {
    if (section == 0) {
        return @"Followed Data";
    }
    else {
        return @"All Data";
    }
}

行数

- (NSInteger)tableView:(UITableView *)tableView numberOfRowsInSection:(NSInteger)section {
    
    if (!isFiltered) {
        
        if (section == 0) {
            return [followedArray count];
        }
        else if (section == 1) {
            return [dataArray count];
        }
    }
    return [filteredArray count];
}

---------------------------------------- --------------

--这是动作发生的地方--

---------------------------------------- --------------

关注按钮

-(void)followButtonClick:(UIButton *)sender {
    
    // Adding row to tag
    CGPoint buttonPosition = [sender convertPoint:CGPointZero toView:self.myTableView];
    NSIndexPath *indexPath = [self.myTableView indexPathForRowAtPoint:buttonPosition];
    
    // Creating an action per tag
    if (indexPath != nil)
    {
        NSLog(@"Current Row = %@", indexPath);
        
        
        // ----- ERROR HERE -----
    [self.myTableView beginUpdates];
    
    // ----- Inserting Cell to Section 0 ----- *NOT WORKING*
    [followedArray insertObject:[dataArray objectAtIndex:indexPath.row] atIndex:indexPath.row];
    NSInteger rowToAdd = indexPath.row;
    [self.myTableView insertRowsAtIndexPaths:[NSMutableArray arrayWithObjects:[NSIndexPath indexPathForRow:rowToAdd inSection:0], nil] withRowAnimation:YES];
    
    // ----- Removing Cell from Section 1 ----- *WORKING*
    [dataArray removeObjectAtIndex:indexPath.row];
    NSInteger rowToRemove = indexPath.row;
    [self.myTableView deleteRowsAtIndexPaths:[NSMutableArray arrayWithObjects:[NSIndexPath indexPathForRow:rowToRemove inSection:1], nil] withRowAnimation:YES];
    
    [self.myTableView endUpdates];
        
    }
}

Answer 1

这可能是因为您正在使用 convertPoint 获取所单击单元格的 indexPath。尝试在您的 CustomCell 中创建一个协议并在您的 CustomCell 中实现您的 followButtonClick 并使用委托在您的控制器中使用您的 CustomCell 对象获取回调并使用该对象获取 indexPath。请参考以下代码。

你的CustomCell.h #导入

@protocol CustomCellDelegate;

@interface CustomCell : UITableViewCell

@property(nonatomic,weak) id<CustomCellDelegate> delegate;

@end

@protocol CustomCellDelegate <NSObject>

-(void)followButtonClickedWithCell:(CustomCell *) cell;

@end

你的CustomCell.m

#import "CustomCell.h"

@implementation CustomCell
...
-(void)followButtonClicked:(UIButton *) sender{
    if(self.delegate != nil){
        [self.delegate followButtonClickedWithCell:self];
    }
}

...
@end

确认你的view controller实现了CustomCellDelegate，在delegate方法中参考下面的代码获取被点击的indexPath

-(void)followButtonClickedWithCell:(CustomCell *) cell{
    NSIndexPath *clickedIndexPath = [self.tableView indexPathForCell:cell];
    if (clickedIndexPath != nil){
        //Implement your logic here
    }
}

Answer 2

修改关注按钮代码如下：

关注按钮

-(void)followButtonClick:(UIButton*)sender {
    //Use this IndexPath
    NSInteger buttonTag = [sender tag];
    NSIndexPath *indexPath = [NSIndexPath indexPathForRow:buttonTag inSection:<YourSection>];

    // Creating an action per tag
    if (indexPath != nil)
    {
        NSLog(@"Current Row = %@", indexPath);


        // ----- ERROR HERE -----

        [self.myTableView beginUpdates];

        // ----- Inserting Cell to Section 0 -----
        [followedArray insertObject:[dataArray objectAtIndex:indexPath.row] atIndex:indexPath.row];
        NSInteger rowToAdd = indexPath.row;
        [self.myTableView insertRowsAtIndexPaths:[NSMutableArray arrayWithObjects:[NSIndexPath indexPathForRow:rowToAdd inSection:0], nil] withRowAnimation:YES];

        // ----- Removing Cell from Section 1 -----
        [dataArray removeObjectAtIndex:indexPath.row];
        NSInteger rowToRemove = indexPath.row;
        [self.myTableView deleteRowsAtIndexPaths:[NSMutableArray arrayWithObjects:[NSIndexPath indexPathForRow:rowToRemove inSection:1], nil] withRowAnimation:YES];

        [self.myTableView endUpdates];

    }

}

Answer 3

这就是帮助我修复错误的原因，感谢@AliOmari、@Rachel 和@CodeChanger

    [self.myTableView beginUpdates];

    [followedArray insertObject:[dataArray objectAtIndex:indexPath.row] atIndex:0];
    [myTableView insertRowsAtIndexPaths:@[[NSIndexPath indexPathForRow:0 inSection:0]] withRowAnimation:UITableViewRowAnimationFade];

    [dataArray removeObjectAtIndex:indexPath.row];
    NSInteger rowToRemove = indexPath.row;
    [self.myTableView deleteRowsAtIndexPaths:[NSMutableArray arrayWithObjects:[NSIndexPath indexPathForRow:rowToRemove inSection:1], nil] withRowAnimation:YES];

    [self.myTableView endUpdates];

在 NSMutableArray 之间移动 objects 时出错

Error when moving objects between NSMutableArray

objective-c

uitableview

nsmutablearray

ios