ios - 在 iOS 的 UItableview 中将行推到顶部

Question

我有 uitableview，每行都有 1 个按钮“TOP”。我想当用户单击此按钮时，此行已在 Uitableview 中被推到顶部（带有动画）。我可以重复使用BVReorderTableView吗？我怎样才能做到这一点？非常感谢

Answer 1

我假设您-cellForRowAtIndexPath从数组中加载单元格内容，例如我命名的数组arrObjects：

1. 是一个NSMutableArray对象
2. 有很多NSString对象

就像是：

- (UITableViewCell *)tableView:(UITableView *)tableView
         cellForRowAtIndexPath:(NSIndexPath *)indexPath {
    //...
    [cell.textLabel setText:[arrObjects objectAtIndex:indexPath.row]];

    UIButton *btnUp = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    [btnUp setFrame:CGRectMake(0, 0, 30, 30)];
    //[btnUp setTag:100];
    [btnUp setTitle:@"\u261D" forState:UIControlStateNormal];
    [btnUp addTarget:self
              action:@selector(moveToTop:)
    forControlEvents:UIControlEventTouchUpInside];
    [cell setAccessoryView:btnUp];

    return cell;
}

---

- (void)moveToTop:(UIButton *)sender
{
    UITableViewCell *cell = (UITableViewCell *)sender.superview; //iOS6 prior
    //UITableViewCell *cell = (UITableViewCell *)sender.superview.superview; //iOS7

    NSIndexPath *indexPath = [self.tableView indexPathForCell:cell];

    //uncomment lines for safety, incase indexPath ever comes nil... prevent the crash
    //if (indexPath == nil) {
    //    return;
    //}

    //1. move and animate row to top
    [self.tableView moveRowAtIndexPath:[NSIndexPath indexPathForItem:indexPath.row
                                                           inSection:indexPath.section]
                           toIndexPath:[NSIndexPath indexPathForItem:0
                                                           inSection:indexPath.section]];


    //2. make appropriate changes to the datasource
    //so that it reflects logically and is not just an aestehtical change

    //PRE-NOTE:
    //arrObjects is an object of a category on NSMutableArray
    //with a custom instance method named -moveObjectFromIndexPath:toIndex:

    //uncomment the following line when you are ready with the category
    //[arrObjects moveObjectFromIndex:indexPath.row toIndex:0];
}

该类别很容易创建，请遵循： http:
//www.icab.de/blog/2009/11/15/moving-objects-within-an-nsmutablearray/

---

其他尝试链接：

1. http://adeem.me/blog/2009/05/29/iphone-sdk-tutorial-add-delete-reorder-uitableview-row/
2. http://learn-iphone-app-development.com/2011/01/31/tables-part-iii-%E2%80%94-re-ordering-moving-cells-and-swipe-to-delete/

Answer 2

你有没有尝试过

- (void)tableView:(UITableView *)tableView moveRowAtIndexPath:(NSIndexPath *)sourceIndexPath toIndexPath:(NSIndexPath *)destinationIndexPath;

如果你愿意，你可以使用动画..

Answer 3

你可以像这样轻松地做到这一点：

[self.tableView setContentOffset:CGPointMake(0, 0) animated:YES];

或者：

[self.tableView scrollToRowAtIndexPath:[NSIndexPath indexPathForRow:0 inSection:0] atScrollPosition:UITableViewScrollPositionBottom animated:YES];

或者：

[self.tableView scrollRectToVisible:CGRectMake(0.f, 0.f, CGRectGetWidth(self.tableView.frame), CGRectGetHeight(self.tableView.frame)) animated:YES];

编辑
对不起，我误解了你的意思。你应该这样做：

[tableView moveRowAtIndexPath:indexPath toIndexPath:[NSIndexPath indexPathForRow:0 inSection:0]];

如果您想在移动单元格后立即将 tableView 滚动到顶部，可以尝试上面的代码。

编辑

    // A more detailed description
- (void)buttonHandle:(UIButton *)sender {
    // Assuming button is added directly on the cell.
    UITableViewCell *cell = (UITableViewCell *)sender.superview;
    NSIndexPath *indexPath = [tableView indexPathForCell:cell];
    [tableView moveRowAtIndexPath:indexPath toIndexPath:[NSIndexPath indexPathForRow:0 inSection:0]];
}