当在NestedScrollView内时，RecyclerView会夺取焦点 [英] RecyclerView steals focus when inside a NestedScrollView

问题描述

当我将RecyclerView放入嵌套的滚动视图中时，屏幕总是跳到RecyclerView的顶部而不是页面的顶部.这是一个简单的例子.

When I put a RecyclerView inside a nested scrollview, the screen always jumps to the top of the RecyclerView instead of the top of the page. Here is a simple example.

布局xml:

<?xml version="1.0" encoding="utf-8"?>
<layout xmlns:tools="http://schemas.android.com/tools"
    xmlns:android="http://schemas.android.com/apk/res/android">
<android.support.v4.widget.NestedScrollView
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <LinearLayout
        android:orientation="vertical"
        android:layout_width="match_parent"
        android:layout_height="wrap_content">
        <RelativeLayout
            android:layout_width="match_parent"
            android:layout_height="350dp"
            android:background="@android:color/holo_blue_dark"/>
        <android.support.v7.widget.RecyclerView
            android:id="@+id/recycleView"
            android:layout_width="match_parent"
            android:layout_height="wrap_content" />
    </LinearLayout>
</android.support.v4.widget.NestedScrollView>
</layout>

具有虚拟适配器的活动:

Activity with dummy adapter:

public class RecycleViewTestActivity extends AppCompatActivity {

public static class ExampleAdapter extends RecyclerView.Adapter<ExampleViewHolder> {

    private Context context;

    public ExampleAdapter(Context context) {
        this.context = context;
    }

    @Override
    public ExampleViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        TextView view = new TextView(context);
        view.setText("Test");
        return new ExampleViewHolder(view);
    }

    @Override
    public void onBindViewHolder(ExampleViewHolder holder, int position) {

    }

    @Override
    public int getItemCount() {
        return 100;
    }
}

public static class ExampleViewHolder extends RecyclerView.ViewHolder {

    public ExampleViewHolder(View itemView) {
        super(itemView);
    }
}

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_rectest);
    RecyclerView view = (RecyclerView) findViewById(R.id.recycleView);
    view.setNestedScrollingEnabled(false);
    view.setLayoutManager(new LinearLayoutManager(this));
    ExampleAdapter adapter = new ExampleAdapter(this);
    view.setAdapter(adapter);
}

}

在此示例中，我在recycleview上有一个350dp高的空视图，因为您需要在RecycleView上有一些内容才能明显地显示出来. RecycleView本身包含100个虚拟textview.

In this example I have a 350dp tall empty view over the recycleview because you need to have some content over the RecycleView for this to show up obviously. The RecycleView iteself contains 100 dummy textviews.

开始活动后，滚动条位于RecycleView的顶部而不是页面的顶部.它必须在LinearLayoutManager中，但是还没有真正看到.

After you start the activity, the scroll is at the top of the RecycleView instead of the top of the page. It must be something inside the LinearLayoutManager, but havent really looked yet.

任何想法如何解决这个问题?

Any ideas how to solve this?

推荐答案

使您的顶视图更具针对性. "RecyclerView将"focusableOnTouchMode"设置为true，以处理布局过程中其子级的焦点更改."相关讨论该问题.

Make your top view focusable. "RecyclerView has "focusableOnTouchMode" set to true to handle its childrens' focus changes during layout." Relevant discussion of the issue.

示例:

<android.support.v4.widget.NestedScrollView
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:focusableInTouchMode="true"
        android:orientation="vertical">

        <View
            android:id="@+id/someView"
            android:layout_width="wrap_content"
            android:layout_height="350dp"/>

        <android.support.v7.widget.RecyclerView
            android:id="@+id/recyclerView"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"/>

    </LinearLayout>
</android.support.v4.widget.NestedScrollView>

这篇关于当在NestedScrollView内时，RecyclerView会夺取焦点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！