MvxRecyclerView Fluent API绑定 [英] MvxRecyclerView Fluent API binding

问题描述

我无法使用Fluent API将MvxRecyclerView(或其适配器)的ItemClick绑定到ViewModel上的命令.如果将ItemsSource和ItemClick都放在XML中，则它可以工作，因此我对这种解决方案不感兴趣.

I am unable to bind ItemClick from MvxRecyclerView (or its Adapter) to a command on my ViewModel using Fluent API. It works if I put both ItemsSource and ItemClick in the XML so I am not interested in such solution.

我将此帖子用作出色的指导原则(

I used this post as an excellent guideline (How to use the MvvmCross fluent API to bind a RecyclerView item's TextView to a property of its ViewModel on Android?) and all of that works except that I am unable to bind ItemClick on MvxRecyclerView (or the adapter) to a MainViewModel's command which will take me to the next fragment (ItemsSource works like a charm but its a property and not a command!).

为了简洁起见，我不会从原始帖子中复制代码(

For the sake of brevity, I will not be copying the code from the original post (How to use the MvvmCross fluent API to bind a RecyclerView item's TextView to a property of its ViewModel on Android?) so assume that the MainViewModel from that post has been enhanced with a command ShowItemCommand as such:

public class MainViewModel : MvxViewModel
{
    private IEnumerable<ViewModelItem> _viewModelItems;
    public IEnumerable<ViewModelItem> ViewModelItems
    {
        get { return _viewModelItems; }
        set { SetProperty(ref _viewModelItems, value); }
    }    

    public MvxCommand<ViewModelItem> ShowItemCommand
    {
        get
        {
            return new MvxCommand<ViewModelItem>(selectedItem =>
            {
                ShowViewModel<ViewModelItem>
                (new { itemId = selectedItem.Id });
            });
        }
    }
}

，所有其他内容均已按照引用的帖子实施.

and everything else has been implemented as per the referenced post.

所以现在，除了ItemsSource，我还要将MvxRecyclerView(或适配器)上的ItemClick连接到命令.它们可互换的原因是MvxRecyclerView只是将这些命令中继到适配器.

So now, in addition to ItemsSource, I want to wire up ItemClick on the MvxRecyclerView (or the Adapter) to the command. The reason these are interchangeable is that MvxRecyclerView just relays these commands to the Adapter.

显然，这应该可以...但是不能:

Apparently, this should work...but it does not:

adapter.ItemClick = ViewModel.ShowItemCommand;

这也不起作用:

set.Bind(recyclerView).For(v => v.ItemClick).To(vm => vm.ShowItemCommand);

推荐答案

创建自定义MvxRecyclerViewHolder时，需要确保将Click命令分配给ViewHolder.这是在您的自定义适配器的OnCreateViewHolder替代中完成的.

When creating a custom MvxRecyclerViewHolder you need to make sure that you assign the Click command over to the ViewHolder. This is done in the OnCreateViewHolder override of your custom adapter.

自定义ViewHolder

public class MyAdapter : MvxRecyclerAdapter
{
    public MyAdapter(IMvxAndroidBindingContext bindingContext)
        : base(bindingContext)
    {
    }

    public override RecyclerView.ViewHolder OnCreateViewHolder(ViewGroup parent, int viewType)
    {
        var itemBindingContext = new MvxAndroidBindingContext(parent.Context, this.BindingContext.LayoutInflaterHolder);
        var view = this.InflateViewForHolder(parent, viewType, itemBindingContext);

        return new MyViewHolder(view, itemBindingContext)
        {
            Click = ItemClick,
            LongClick = ItemLongClick
        };
    }
}

这篇关于MvxRecyclerView Fluent API绑定的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！