//设Cell可编辑
- (BOOL)tableView:(UITableView *)tableView canEditRowAtIndexPath:(NSIndexPath *)indexPath
{
  return YES;
}
//设置删除按钮
-(UITableViewCellEditingStyle)tableView:(UITableView *)tableView editingStyleForRowAtIndexPath:(NSIndexPath *)indexPath
{
  return UITableViewCellEditingStyleDelete;
}
//进入编辑（删除）模式
-(void)tableView:(UITableView *)tableView commitEditingStyle:(UITableViewCellEditingStyle)editingStyle forRowAtIndexPath:(NSIndexPath *)indexPath
{  
  //出现alterView隐藏删除按钮
  [tableView setEditing:NO animated:YES];
  if (editingStyle == UITableViewCellEditingStyleDelete) {
    UIAlertController *alertController = [UIAlertController alertControllerWithTitle:@"提示" message:@"你确定删除该消息？" preferredStyle:UIAlertControllerStyleAlert];
    [alertController addAction:[UIAlertAction actionWithTitle:@"取消" style:UIAlertActionStyleCancel handler:nil]];
    [alertController addAction:[UIAlertAction actionWithTitle:@"确定" style:UIAlertActionStyleDestructive handler:^(UIAlertAction * _Nonnull action) {
      //需要先删除数据源中对应数据，不然执行下一步会崩溃
      [reconnaissanceListArr removeObjectAtIndex:indexPath.row];
      [tableView deleteRowsAtIndexPaths:@[indexPath] withRowAnimation:UITableViewRowAnimationAutomatic];
    }]];
    [self presentViewController:alertController animated:YES completion:nil];
  }
}
//修改编辑按钮文字
-(NSString *)tableView:(UITableView *)tableView titleForDeleteConfirmationButtonForRowAtIndexPath:(NSIndexPath *)indexPath
{
  return @"删除";
}
//设置进入编辑状态时，Cell不会缩进
- (BOOL)tableView: (UITableView *)tableView shouldIndentWhileEditingRowAtIndexPath:(NSIndexPath *)indexPath
{
  return NO;
}