如何将活动转换为片段？

Question

我有这段代码，但每次我尝试将其更改为片段时，我总是会出错。谁能帮我解决这个问题？

这是我的带有卡片视图的 RecyclerViewAdapter

公共类 RecyclerViewAdapter 扩展RecyclerView.Adapter {

private Context mContext ;
private List<Book> mData ;


public RecyclerViewAdapter(Context mContext, List<Book> mData) {
    this.mContext = mContext;
    this.mData = mData;
}

@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

    View view ;
    LayoutInflater mInflater = LayoutInflater.from(mContext);
    view = mInflater.inflate(R.layout.cardveiw_item_book,parent,false);
    return new MyViewHolder(view);
}

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

    holder.tv_book_title.setText(mData.get(position).getTitle());
    holder.img_book_thumbnail.setImageResource(mData.get(position).getThumbnail());
    holder.cardView.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {

            Intent intent = new Intent(mContext,Book_Activity.class);

            // passing data to the book activity
            intent.putExtra("Title",mData.get(position).getTitle());
            intent.putExtra("Description",mData.get(position).getDescription());
            intent.putExtra("Thumbnail",mData.get(position).getThumbnail());
            // start the activity
            mContext.startActivity(intent);

        }
    });



}

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

public static class MyViewHolder extends RecyclerView.ViewHolder {

    TextView tv_book_title;
    ImageView img_book_thumbnail;
    CardView cardView ;

    public MyViewHolder(View itemView) {
        super(itemView);

        tv_book_title = (TextView) itemView.findViewById(R.id.book_title_id) ;
        img_book_thumbnail = (ImageView) itemView.findViewById(R.id.book_img_id);
        cardView = (CardView) itemView.findViewById(R.id.cardview_id);


    }
}

}

这是用于 MainActivity

公共类 MainActivity 扩展 AppCompatActivity {

List<Book> lstBook ;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    lstBook = new ArrayList<>();
    lstBook.add(new Book("The Vegitarian","Categorie Book","Description book",R.drawable.thevigitarian));
    lstBook.add(new Book("The Wild Robot","Categorie Book","Description book",R.drawable.thewildrobot));
    lstBook.add(new Book("Maria Semples","Categorie Book","Description book",R.drawable.mariasemples));
    lstBook.add(new Book("The Martian","Categorie Book","Description book",R.drawable.themartian));

    RecyclerView myrv = (RecyclerView) findViewById(R.id.reyclerview_id);
    RecyclerViewAdapter myAdapter = new RecyclerViewAdapter(this,lstBook);
    myrv.setLayoutManager(new GridLayoutManager(this,2));
    myrv.setAdapter(myAdapter);


}

}

如何将我的 Main Activity 转换为 Fragment？

Answer 1

超级简单

public class MainActivity extends Fragment {

List<Book> lstBook ;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    lstBook = new ArrayList<>();
    lstBook.add(new Book("The Vegitarian","Categorie Book","Description book",R.drawable.thevigitarian));
    lstBook.add(new Book("The Wild Robot","Categorie Book","Description book",R.drawable.thewildrobot));
    lstBook.add(new Book("Maria Semples","Categorie Book","Description book",R.drawable.mariasemples));
    lstBook.add(new Book("The Martian","Categorie Book","Description book",R.drawable.themartian));
}


@Nullable @Override public View onCreateView(LayoutInflater inflater, ViewGroup container,
      Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.activity_main,container)
RecyclerView myrv = (RecyclerView) view.findViewById(R.id.reyclerview_id);
    RecyclerViewAdapter myAdapter = new RecyclerViewAdapter(getActivity(),lstBook);
    myrv.setLayoutManager(new GridLayoutManager(this,2));
    myrv.setAdapter(myAdapter)
return view;
  }
}