如何在recyclerview中拥有可变的行高

Question

我正在尝试在导航抽屉中创建一个recyclerview,其标题显示了配置文件信息.我希望标题高度高于其他行元素.下面是我的标题布局

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="200dp"
    android:background="@color/green"
    android:orientation="vertical"
    android:weightSum="1">



    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="56dp"
        android:orientation="vertical"
        android:layout_alignParentBottom="true"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true">

        <TextView
            android:id="@+id/name"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_marginLeft="16dp"
            android:textColor="#ffffff"
            android:text="XXXXX"
            android:textSize="32sp"
            android:textStyle="bold"
            />

    </LinearLayout>

</RelativeLayout>

当我将其设置为回收器视图的标题时,200dp高度不会反映在UI中

 RecyclerView.Adapter<NavDrawerListViewHolder> adapter = new NavDrawerListAdapter(this,TITLES,this);
        navList.setAdapter(adapter);

以下是recyclerview的适配器:

public class NavDrawerListAdapter extends RecyclerView.Adapter<NavDrawerListViewHolder> {

    private static final int TYPE_HEADER = 0;
    private static final int TYPE_ITEM = 1;
    Context mContext;
    String[] mCharacterList;
    IListItemClickListener mListener;
    int holderViewType=0;

    public NavDrawerListAdapter(Context context, String[] characters, IListItemClickListener clickListener) {
        mContext = context;
        mCharacterList = characters;
        mListener = clickListener;
    }

    @Override
    public NavDrawerListViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
        NavDrawerListViewHolder viewHolder;
        holderViewType = viewType;
        if(viewType == TYPE_HEADER) {
            View v = LayoutInflater.from(mContext).inflate(R.layout.header,null);
            viewHolder = new NavDrawerListViewHolder(v,TYPE_HEADER,mListener);
        } else  {
            View v = LayoutInflater.from(mContext).inflate(R.layout.nav_item_row,null);
            viewHolder = new NavDrawerListViewHolder(v,TYPE_ITEM,mListener);
        }

        return viewHolder;
    }

    @Override
    public void onBindViewHolder(NavDrawerListViewHolder holder, int position) {
        if(holderViewType == TYPE_HEADER) {
            Typeface typeface = Typeface.createFromAsset(mContext.getAssets(), "Roboto-Thin.ttf");
            holder.name.setTypeface(typeface);
        } else {
            holder.characterName.setText(mCharacterList[position - 1]);
        }

    }

    @Override
    public int getItemViewType(int position) {
        if (position == 0) {
            return TYPE_HEADER;
        }

        return TYPE_ITEM;
    }

    @Override
    public int getItemCount() {
        return mCharacterList.length + 1;
    }

Answer 1

更换:

LayoutInflater.from(mContext).inflate(R.layout.header,null);

有:

LayoutInflater.from(mContext).inflate(R.layout.header, parent, false);

所有其他inflate()电话都一样.如果您知道要扩充的布局的父容器,请始终将其提供给inflate()呼叫.特别是,RelativeLayout如果它是被夸大的布局的根视图,则需要这个.

此外,考虑使用getLayoutInflater()的Activity替代LayoutInflater.from().这可能是因为,如果你通过Activity进入from(),你会得到相同的结果.但是,一般情况下,您总是希望使用LayoutInflater了解Activity其主题的内容,以便获得正确的结果.