Ios 如何在2个不同的UICollectionViewFlowLayout实例之间切换？

我已经为此工作了几天了。我正在尝试允许应用程序的客户在购物时在两种显示类型之间切换

现在我正在使用2个

UICollectionView

，它们有自己的自定义

UICollectionViewCell

，在这两个视图之间切换很好，但我发现使用2个不同的

UICollectionView

，正在成为一种痛苦。我为主

UICollectionView

实现的某些东西在备选

UICollectionView

中无法正常工作

这就是显示的更改方式。我将

UISegmentedControl

与自定义方法一起使用：

- (void)displayTypeSegmentSelected
{
    _selectedDisplayTypeIndex = [_displayTypeControl selectedSegmentIndex];


    if (_selectedDisplayTypeIndex == 0) {
        NSLog(@"Single file item view selected");
        _fromCollectionView = _collectionView;
        _toCollectionView = _collectionView2;


    } else if (_selectedDisplayTypeIndex == 1) {
        NSLog(@"Grid style view selected");
        _fromCollectionView = _collectionView2;
        _toCollectionView = _collectionView;
    }

    [_fromCollectionView removeFromSuperview];

    [_toCollectionView setFrame:[_superView bounds]];
    [_superView addSubview:_toCollectionView];

}

通过stackoverflow，我得到了两个不同的建议，关于如何更好地完成我想做的事情。

- (void)displayTypeSegmentSelected
{
    _selectedDisplayTypeIndex = [_displayTypeControl selectedSegmentIndex];

    if (_selectedDisplayTypeIndex == 0) {
        NSLog(@"Single file item view selected");
        [_collectionView setCollectionViewLayout:_flowLayout2 animated:YES];
        [_collectionView reloadItemsAtIndexPaths:[_collectionView indexPathsForVisibleItems]];


    } else if (_selectedDisplayTypeIndex == 1) {
        NSLog(@"Grid style view selected");
        [_collectionView setCollectionViewLayout:_flowLayout animated:YES];
        [_collectionView reloadItemsAtIndexPaths:[_collectionView indexPathsForVisibleItems]];
    }

}

-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath object:(PFObject *)object
{

        NSLog(@"collectionview 1 loaded");

        static NSString *CellIdentifier = @"Cell";
        VAGGarmentCell *cell = [_collectionView dequeueReusableCellWithReuseIdentifier: CellIdentifier forIndexPath:indexPath];
        static NSString *CellIdentifier2 = @"Cell2";
        VAGGarmentCell2 *cell2 = [_collectionView dequeueReusableCellWithReuseIdentifier:CellIdentifier2 forIndexPath:indexPath];


    if ([[_collectionView collectionViewLayout] isEqual: _flowLayout]) {
        [[cell activityIndicator] startAnimating];

        PFFile *userImageFile = [object valueForKey:@"image"];
        [[cell imageView] setFile: userImageFile];
        [[cell imageView] loadInBackground];

        [[cell activityIndicator] stopAnimating];

        [[cell title] setText:[object valueForKey:@"title"]];
        [[cell price] setText:[NSString stringWithFormat: @"£%@ GBP", [object valueForKey:@"price"]]];
        return cell;

    } else if ([[_collectionView collectionViewLayout] isEqual: _flowLayout2]) {
        [[cell2 activityIndicator] startAnimating];

        PFFile *userImageFile = [object valueForKey:@"image"];
        [[cell2 imageView] setFile: userImageFile];
        [[cell2 imageView] loadInBackground];

        [[cell2 activityIndicator] stopAnimating];

        [[cell2 title] setText:[object valueForKey:@"title"]];
        [[cell2 price] setText:[NSString stringWithFormat: @"£%@ GBP", [object valueForKey:@"price"]]];
        return cell2;
    }

     return 0;

    //_addToFavouritesButton = [cell addFavouriteButton];

    [_addToFavouritesButton addTarget:_thisController action:@selector(addToFavouritesButtonTapped:) forControlEvents:UIControlEventTouchUpInside];
}

// Grab cell nib file and give a reuse identifier
[_collectionView registerNib:[UINib nibWithNibName:@"VAGGarmentCell2" bundle:nil] forCellWithReuseIdentifier:@"Cell2"];

使用2

UICollectionViewFlowLayout

，并在它们之间切换，而不是使用2

UICollectionView

根据选择的段返回相应的自定义

UICollectionViewCell

我觉得第一种方法会更好。我需要将接口生成器

UICollectionViewFlowLayout

设置为IBOutlet，因为连接的

UICollectionView

不是以编程方式创建的。然后我将以编程方式创建第二个

UICollectionViewFlowLayout

在我的displayTypeSegmentSelected方法中，我将根据所选的段加载两个

UICollectionViewFlowLayout

中的一个

单个文件显示如下所示：

- (void)displayTypeSegmentSelected
{
    _selectedDisplayTypeIndex = [_displayTypeControl selectedSegmentIndex];


    if (_selectedDisplayTypeIndex == 0) {
        NSLog(@"Single file item view selected");
        _fromCollectionView = _collectionView;
        _toCollectionView = _collectionView2;


    } else if (_selectedDisplayTypeIndex == 1) {
        NSLog(@"Grid style view selected");
        _fromCollectionView = _collectionView2;
        _toCollectionView = _collectionView;
    }

    [_fromCollectionView removeFromSuperview];

    [_toCollectionView setFrame:[_superView bounds]];
    [_superView addSubview:_toCollectionView];

}

网格样式显示如下所示：

- (void)displayTypeSegmentSelected
{
    _selectedDisplayTypeIndex = [_displayTypeControl selectedSegmentIndex];


    if (_selectedDisplayTypeIndex == 0) {
        NSLog(@"Single file item view selected");
        _fromCollectionView = _collectionView;
        _toCollectionView = _collectionView2;


    } else if (_selectedDisplayTypeIndex == 1) {
        NSLog(@"Grid style view selected");
        _fromCollectionView = _collectionView2;
        _toCollectionView = _collectionView;
    }

    [_fromCollectionView removeFromSuperview];

    [_toCollectionView setFrame:[_superView bounds]];
    [_superView addSubview:_toCollectionView];

}

问题：

- (void)displayTypeSegmentSelected
{
    _selectedDisplayTypeIndex = [_displayTypeControl selectedSegmentIndex];


    if (_selectedDisplayTypeIndex == 0) {
        NSLog(@"Single file item view selected");
        _fromCollectionView = _collectionView;
        _toCollectionView = _collectionView2;


    } else if (_selectedDisplayTypeIndex == 1) {
        NSLog(@"Grid style view selected");
        _fromCollectionView = _collectionView2;
        _toCollectionView = _collectionView;
    }

    [_fromCollectionView removeFromSuperview];

    [_toCollectionView setFrame:[_superView bounds]];
    [_superView addSubview:_toCollectionView];

}

我想我有一个正确的想法，那就是如何按照我最初的问题去做，如何去做。不过，我会从经验丰富的开发人员那里介绍一个观点和示例。 你会如何做到这一点，你能给我一个清晰的例子，我可以去乱搞吗

---

亲切的问候

这就是我最后做事情的方式

点击特定分段控件后，我更改布局并重新加载单元格。

- (void)displayTypeSegmentSelected
{
    _selectedDisplayTypeIndex = [_displayTypeControl selectedSegmentIndex];

    if (_selectedDisplayTypeIndex == 0) {
        NSLog(@"Single file item view selected");
        [_collectionView setCollectionViewLayout:_flowLayout2 animated:YES];
        [_collectionView reloadItemsAtIndexPaths:[_collectionView indexPathsForVisibleItems]];


    } else if (_selectedDisplayTypeIndex == 1) {
        NSLog(@"Grid style view selected");
        [_collectionView setCollectionViewLayout:_flowLayout animated:YES];
        [_collectionView reloadItemsAtIndexPaths:[_collectionView indexPathsForVisibleItems]];
    }

}

-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath object:(PFObject *)object
{

        NSLog(@"collectionview 1 loaded");

        static NSString *CellIdentifier = @"Cell";
        VAGGarmentCell *cell = [_collectionView dequeueReusableCellWithReuseIdentifier: CellIdentifier forIndexPath:indexPath];
        static NSString *CellIdentifier2 = @"Cell2";
        VAGGarmentCell2 *cell2 = [_collectionView dequeueReusableCellWithReuseIdentifier:CellIdentifier2 forIndexPath:indexPath];


    if ([[_collectionView collectionViewLayout] isEqual: _flowLayout]) {
        [[cell activityIndicator] startAnimating];

        PFFile *userImageFile = [object valueForKey:@"image"];
        [[cell imageView] setFile: userImageFile];
        [[cell imageView] loadInBackground];

        [[cell activityIndicator] stopAnimating];

        [[cell title] setText:[object valueForKey:@"title"]];
        [[cell price] setText:[NSString stringWithFormat: @"£%@ GBP", [object valueForKey:@"price"]]];
        return cell;

    } else if ([[_collectionView collectionViewLayout] isEqual: _flowLayout2]) {
        [[cell2 activityIndicator] startAnimating];

        PFFile *userImageFile = [object valueForKey:@"image"];
        [[cell2 imageView] setFile: userImageFile];
        [[cell2 imageView] loadInBackground];

        [[cell2 activityIndicator] stopAnimating];

        [[cell2 title] setText:[object valueForKey:@"title"]];
        [[cell2 price] setText:[NSString stringWithFormat: @"£%@ GBP", [object valueForKey:@"price"]]];
        return cell2;
    }

     return 0;

    //_addToFavouritesButton = [cell addFavouriteButton];

    [_addToFavouritesButton addTarget:_thisController action:@selector(addToFavouritesButtonTapped:) forControlEvents:UIControlEventTouchUpInside];
}

// Grab cell nib file and give a reuse identifier
[_collectionView registerNib:[UINib nibWithNibName:@"VAGGarmentCell2" bundle:nil] forCellWithReuseIdentifier:@"Cell2"];

在我的

单元格ForItemAtIndexPath

中，根据屏幕上显示的布局，我加载了具有正确设置的特定自定义单元格。

- (void)displayTypeSegmentSelected
{
    _selectedDisplayTypeIndex = [_displayTypeControl selectedSegmentIndex];

    if (_selectedDisplayTypeIndex == 0) {
        NSLog(@"Single file item view selected");
        [_collectionView setCollectionViewLayout:_flowLayout2 animated:YES];
        [_collectionView reloadItemsAtIndexPaths:[_collectionView indexPathsForVisibleItems]];


    } else if (_selectedDisplayTypeIndex == 1) {
        NSLog(@"Grid style view selected");
        [_collectionView setCollectionViewLayout:_flowLayout animated:YES];
        [_collectionView reloadItemsAtIndexPaths:[_collectionView indexPathsForVisibleItems]];
    }

}

-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath object:(PFObject *)object
{

        NSLog(@"collectionview 1 loaded");

        static NSString *CellIdentifier = @"Cell";
        VAGGarmentCell *cell = [_collectionView dequeueReusableCellWithReuseIdentifier: CellIdentifier forIndexPath:indexPath];
        static NSString *CellIdentifier2 = @"Cell2";
        VAGGarmentCell2 *cell2 = [_collectionView dequeueReusableCellWithReuseIdentifier:CellIdentifier2 forIndexPath:indexPath];


    if ([[_collectionView collectionViewLayout] isEqual: _flowLayout]) {
        [[cell activityIndicator] startAnimating];

        PFFile *userImageFile = [object valueForKey:@"image"];
        [[cell imageView] setFile: userImageFile];
        [[cell imageView] loadInBackground];

        [[cell activityIndicator] stopAnimating];

        [[cell title] setText:[object valueForKey:@"title"]];
        [[cell price] setText:[NSString stringWithFormat: @"£%@ GBP", [object valueForKey:@"price"]]];
        return cell;

    } else if ([[_collectionView collectionViewLayout] isEqual: _flowLayout2]) {
        [[cell2 activityIndicator] startAnimating];

        PFFile *userImageFile = [object valueForKey:@"image"];
        [[cell2 imageView] setFile: userImageFile];
        [[cell2 imageView] loadInBackground];

        [[cell2 activityIndicator] stopAnimating];

        [[cell2 title] setText:[object valueForKey:@"title"]];
        [[cell2 price] setText:[NSString stringWithFormat: @"£%@ GBP", [object valueForKey:@"price"]]];
        return cell2;
    }

     return 0;

    //_addToFavouritesButton = [cell addFavouriteButton];

    [_addToFavouritesButton addTarget:_thisController action:@selector(addToFavouritesButtonTapped:) forControlEvents:UIControlEventTouchUpInside];
}

// Grab cell nib file and give a reuse identifier
[_collectionView registerNib:[UINib nibWithNibName:@"VAGGarmentCell2" bundle:nil] forCellWithReuseIdentifier:@"Cell2"];

在我的viewDidLoad中，这里是我为单个项目显示的自定义单元格引用nib文件的地方。

- (void)displayTypeSegmentSelected
{
    _selectedDisplayTypeIndex = [_displayTypeControl selectedSegmentIndex];

    if (_selectedDisplayTypeIndex == 0) {
        NSLog(@"Single file item view selected");
        [_collectionView setCollectionViewLayout:_flowLayout2 animated:YES];
        [_collectionView reloadItemsAtIndexPaths:[_collectionView indexPathsForVisibleItems]];


    } else if (_selectedDisplayTypeIndex == 1) {
        NSLog(@"Grid style view selected");
        [_collectionView setCollectionViewLayout:_flowLayout animated:YES];
        [_collectionView reloadItemsAtIndexPaths:[_collectionView indexPathsForVisibleItems]];
    }

}

-(UICollectionViewCell *)collectionView:(UICollectionView *)collectionView cellForItemAtIndexPath:(NSIndexPath *)indexPath object:(PFObject *)object
{

        NSLog(@"collectionview 1 loaded");

        static NSString *CellIdentifier = @"Cell";
        VAGGarmentCell *cell = [_collectionView dequeueReusableCellWithReuseIdentifier: CellIdentifier forIndexPath:indexPath];
        static NSString *CellIdentifier2 = @"Cell2";
        VAGGarmentCell2 *cell2 = [_collectionView dequeueReusableCellWithReuseIdentifier:CellIdentifier2 forIndexPath:indexPath];


    if ([[_collectionView collectionViewLayout] isEqual: _flowLayout]) {
        [[cell activityIndicator] startAnimating];

        PFFile *userImageFile = [object valueForKey:@"image"];
        [[cell imageView] setFile: userImageFile];
        [[cell imageView] loadInBackground];

        [[cell activityIndicator] stopAnimating];

        [[cell title] setText:[object valueForKey:@"title"]];
        [[cell price] setText:[NSString stringWithFormat: @"£%@ GBP", [object valueForKey:@"price"]]];
        return cell;

    } else if ([[_collectionView collectionViewLayout] isEqual: _flowLayout2]) {
        [[cell2 activityIndicator] startAnimating];

        PFFile *userImageFile = [object valueForKey:@"image"];
        [[cell2 imageView] setFile: userImageFile];
        [[cell2 imageView] loadInBackground];

        [[cell2 activityIndicator] stopAnimating];

        [[cell2 title] setText:[object valueForKey:@"title"]];
        [[cell2 price] setText:[NSString stringWithFormat: @"£%@ GBP", [object valueForKey:@"price"]]];
        return cell2;
    }

     return 0;

    //_addToFavouritesButton = [cell addFavouriteButton];

    [_addToFavouritesButton addTarget:_thisController action:@selector(addToFavouritesButtonTapped:) forControlEvents:UIControlEventTouchUpInside];
}

// Grab cell nib file and give a reuse identifier
[_collectionView registerNib:[UINib nibWithNibName:@"VAGGarmentCell2" bundle:nil] forCellWithReuseIdentifier:@"Cell2"];

虽然每次我在不同的布局之间切换时，我的内存都会不断增加，但我会遇到崩溃，但它们很难复制。我猜我需要删除一些旧代码。我明天会把它整理好，用仪器检查一下。然而，这已经完成，我可以继续前进

---

我可能需要在重复自己的地方重构代码。

我在切换collectionView显示的动画时遇到一些问题。你的解决方案也帮助了我

这是我的结果

这就是解决办法

在ViewController中切换操作

            if self.displayType == .grid {
                self.displayType = .table
            }else {
               self.displayType = .grid
            }

            // Only update item size here
            self.updateFlowLayout()

            self.collectionView.performBatchUpdates({

                self.collectionView.setCollectionViewLayout(self.flowLayout, animated: true)

            }, completion: { (finished) in

            })

我正在使用一个collectionViewCell。 覆盖单元的布局子视图

override func layoutSubviews() {
    super.layoutSubviews()
    if (self.bounds.width / self.bounds.height) > 1.4 {
        if self.displayType != .table {
            self.displayType = .table
        }
    }else {

        if self.displayType != .grid {
            self.displayType = .grid
        }
    }
}

和显示类型

var displayType : CastDisplayType = .grid {
        didSet {
            //Update constraints of subviews between cell
            updateLayout()
        }
    }

---

希望它能对一些人有所帮助。

此时，在github上发布一个精简/基本版本的代码可能是值得的，这样任何人都可以使用它。。。祝你好运。我同意你的决定，第一种方法是在布局之间切换。要做到这一点，没有多少事情要做。看起来您已经构建了这两个布局，只需在分段控件的操作方法中使用setCollectionViewLayout:animated:completion:在它们之间切换即可。试着去实现它，如果你遇到麻烦，再问一个更具体的基于代码的问题。@rdelmar，设置它确实花了5分钟，而且效果很好。这部动画片是一种奖励。我现在唯一的问题是切换到的布局使用了原始布局的单元，默认情况下，该单元比我为单视图布局创建的单元小得多。切换时，我获得了单文件视图，由于布局设置（项目插入300x500），单元格被放大，但由于使用了其他布局单元格，图像视图仍然很小。解决这个问题的最佳方法是什么？我想我可以检查cellForItemAtIndex中的当前布局，但事实证明这很困难。只需使用collectionView:layout:SizeForItemIndeXPath:。布局已为您传入，请检查它是哪一个，并返回该布局所需的大小。@rdelmar，这将调整单元格的大小，但不会调整包含项目图像的“我的图像”视图的大小。图像视图保持不变。最终崩溃与此无关。我真的很感谢你在这里所做的一切和你编写的代码。我正在做一些类似的事情，但是我的问题是动画看起来不太好，如果我在布局之间快速切换，所有的单元格都会消失。不太好。