RecyclerView数据绑定项目单击

Question

我试图从Activity本身(而不是来自适配器)监听我的Recycler视图上的行点击(项目点击).

我的适配器到目前为止如下所示:

public class ListMiestnostiAdapter extends RecyclerView.Adapter<ListMiestnostiAdapter.ViewHolder>{
    private List<Miestnost> data;

    // you provide access to all the views for a data item in a view holder
    public static class ViewHolder extends RecyclerView.ViewHolder {
        public ViewDataBinding binding;

        public ViewHolder(ViewDataBinding binding) {
            super(binding.getRoot());
            this.binding = binding;
        }

        public void bind(Object obj){
            binding.setVariable(BR.obj, obj);
            binding.executePendingBindings();
        }
    }

    public ListMiestnostiAdapter(List<Miestnost> data) {
        this.data = data;
    }

    @Override
    public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        // create a new view
        LayoutInflater inflater = LayoutInflater.from(parent.getContext());
        ActivityListMiestnostiRowBinding itemBinding = ActivityListMiestnostiRowBinding.inflate(inflater, parent,false);

        return new ViewHolder(itemBinding);
    }

    @Override
    public void onBindViewHolder(ViewHolder holder, int position) {
        Miestnost item = data.get(position);
        holder.bind(item);
    }

    @Override
    public int getItemCount() {
        return data.size();
    }
}

我的行布局如下:

<layout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:bind="http://schemas.android.com/apk/res-auto">
    <data>
        <variable
            name="obj"
            type="com.example.com.projectname.Models.Miestnost" />
    </data>

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="?android:attr/selectableItemBackground"
        android:clickable="true"
        android:focusable="true"
        android:orientation="horizontal"
        android:paddingBottom="@dimen/row_padding_vertical"
        android:paddingLeft="@dimen/activity_horizontal_margin"
        android:paddingRight="@dimen/activity_horizontal_margin"
        android:paddingTop="@dimen/row_padding_vertical">

        <TextView
            android:id="@+id/txt_miestnost_row_nazov"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_alignParentTop="true"
            android:text="@{obj.Name}"
            android:textSize="16dp" />
    </LinearLayout>
</layout>

正如我已经提到的那样,我正在尝试收听项目点击,但不是来自Adapter本身(如其他帖子所建议的那样),而是来自我的包含此RecyclerView的Activity.

这种行动甚至可能吗？如果是,那么任何帮助都将受到高度赞赏,因为我在谷歌上找不到任何东西.

Answer 1

您首先需要一个指定侦听器行为的接口.在此示例中,有一个名为ContentItem的示例模型,因此单击将返回该类型的项:

public interface OnItemClickListener {
    void onItemClick(ContentItem item);
}

构造函数将接收实现此接口的对象以及要呈现的项:

private final List<ContentItem> items;
private final OnItemClickListener listener;

public ContentAdapter(List<ContentItem> items, OnItemClickListener listener) {
    this.items = items;
    this.listener = listener;
}

您也可以创建一个setOnItemClickListener方法并以这种方式分配它.现在,在onBindViewHolder中,ViewHolder将在自定义绑定方法中接收构造函数:

@Override
public void onBindViewHolder(ViewHolder holder, int position) {
    holder.bind(items.get(position), listener);
}

这是绑定方法的样子:

public void bind(final ContentItem item, final OnItemClickListener listener) {
    ...
    itemView.setOnClickListener(new View.OnClickListener() {
        @Override public void onClick(View v) {
            listener.onItemClick(item);
        }
    });
}

通过创建新的适配器和将在单击项目时实现行为的侦听器,随时使用它.一个简单的例子:

recycler.setAdapter(new ContentAdapter(
    items,
    new ContentAdapter.OnItemClickListener() {
        @Override
        public void onItemClick(ContentItem item) {
            Toast.makeText(getContext(), "Item Clicked", Toast.LENGTH_LONG).show();
        }
    }));

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