Question

我关注了android recycler tutorial，我遇到了以下错误

java.lang.ClassCastException: android.widget.LinearLayout cannot be cast to android.widget.TextView
                                                                             at com.ji.www.i.RecycleAdapter.onCreateViewHolder(RecycleAdapter.java:33)
                                                                             at com.ji.www.i.RecycleAdapter.onCreateViewHolder(RecycleAdapter.java:12)
                                                                             at android.support.v7.widget.RecyclerView$Adapter.createViewHolder(RecyclerView.java:5288)
                                                                             at android.support.v7.widget.RecyclerView$Recycler.getViewForPosition(RecyclerView.java:4551)

这是代码

public class RecycleAdapter extends RecyclerView.Adapter<RecycleAdapter.ViewHolder>{
    private String[] mDataset;

    public static class ViewHolder extends RecyclerView.ViewHolder {
        public TextView mTextView;

        public ViewHolder(TextView v){

        super(v);
            mTextView=v;
    }
    }
    public RecycleAdapter(String[] myDataset)
    {
        mDataset =myDataset;
    }
    @Override
    public RecycleAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType)
    {
        View v= LayoutInflater.from(parent.getContext())
                                .inflate(R.layout.my_textview, parent, false);
        ViewHolder vh=new ViewHolder((TextView)v);
        return vh;
    }
    public void onBindViewHolder(ViewHolder holder ,int position) {
        holder.mTextView.setText(mDataset[position]);
    }
    @Override
    public int getItemCount()
    {
        return mDataset.length;
    }
}

这是xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical" android:layout_width="match_parent"
    android:layout_height="match_parent">
    <TextView
        android:id="@+id/textview"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:paddingLeft="10dp"
        android:hint="Insert here" />
</LinearLayout>

Answer 1

您必须更改ViewHolder构造函数，以便获得对布局中TextView的引用。

public class RecycleAdapter extends RecyclerView.Adapter<RecycleAdapter.ViewHolder>{
    private String[] mDataset;

    public static class ViewHolder extends RecyclerView.ViewHolder {
        public TextView mTextView;

        public ViewHolder(View v){

            super(v);
            TextView mTextView = (TextView) v.findViewById(R.id.textview);
            this.mTextView = mTextView;
        }
    }
    public RecycleAdapter(String[] myDataset)
    {
        mDataset = myDataset;
    }
    @Override
    public RecycleAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType)
    {
        View v= LayoutInflater.from(parent.getContext())
                .inflate(R.layout.my_textview, parent, false);
        ViewHolder vh= new ViewHolder(v);
        return vh;
    }
    public void onBindViewHolder(ViewHolder holder ,int position) {
        holder.mTextView.setText(mDataset[position]);
    }
    @Override
    public int getItemCount()
    {
        return mDataset.length;
    }
}

recyclerview android开发人员教程错误android.widget.LinearLayout无法强制转换为android.widget.TextView

1 个答案: