在IndexPath中移动Row时更新数据源的问题 [英] issue with updating the datasource while moving Row at IndexPath

问题描述

我正在尝试通过滑动手势将行从一个位置移动到另一个位置.当我向右滑动任何一个单元格时，被滑动的单元格应该移至该单元格的底部，为此，我已经编写了代码，并且在某些情况下它可以正常工作，即假设我在索引位置0处滑动了该单元格，它可以正确地转到单元格的底部，假设我在数组中有"A，B，C" ，因此表显示为"A，B，C".现在假设我选择"A" 滑动到底部的 0 位置，现在表格将显示 B，C，A ，这是正确的.现在，我滑过位于位置 1 的"C" ，以便将其移至底部.现在我的表格显示 C，A，B.但实际上它应该显示 B，A，C.

I am trying to move a row from one position to another on swipe gestures, ie. when I swipe right any of the cell, the swiped cell should go to the bottom of the cell, for this I have written the code, and it works fine in some condition i.e suppose I swiped the cell at index position 0 it goes correctly to the bottom of the cell, suppose I have "A, B, C" in my array, so the table displays "A, B, C" .Now suppose I select " A" to swipe which is at position 0 it goes at bottom and and now the table will display B,C,A which is correct. Now I swipe "C" which is at postion 1 so that it should go to bottom. now my table displays C,A,B. But infact it should have displayed B,A,C.

下面是我的代码

if (state == JTTableViewCellEditingStateRight) 
{

   NSIndexPath *selectedIndexPath = [tableView indexPathForSelectedRow];

  [tableView moveRowAtIndexPath:selectedIndexPath toIndexPath:[NSIndexPath indexPathForRow:[self.rows count]-numberOfMoves inSection:0]];  
   [self moveRows];
} 


- (void)moveRows
{

    NSIndexPath *selectedIndexPath = [self.tableView indexPathForSelectedRow];
    NSString *selectedString = [self.rows objectAtIndex:selectedIndexPath.row];     

    [self.rows removeObjectAtIndex:selectedIndexPath.row];
    [self.rows insertObject:selectedString atIndex:[self.rows count]];   
}

问候 兰吉特

推荐答案

让我们分析您的代码:

[self.rows insertObject:selectedString atIndex:[self.rows count]]; 

似乎您将新项始终放在数组的末尾而不是新位置.

it seems you put the new item always to the end of the array and not to the new position.

移动对象的正确方法是使用数据源:

the proper way to move the objects is your data source is the following:

- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)fromIndexPath toIndexPath:(NSIndexPath *)toIndexPath {
    id _object = [self.rows objectAtIndex:fromIndexPath.row];
    [self.rows removeObjectAtIndex:fromIndexPath.row];
    [self.rows insertObject:_object atIndex:toIndexPath.row];
}

这可能会对您有所帮助.

it might helps you.

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