關於適配器的幾個問題

Question

public class AdapterQuestion extends RecyclerView.Adapter<AdapterQuestion.ViewQuestion>{
private LayoutInflater mLayoutInflater;
//this is an arrayList of questionData objects
private ArrayList<QuestionData> data =new ArrayList<>();
//Created the layoutInflator
public AdapterQuestion(Context context){
    //get from context
    mLayoutInflater=LayoutInflater.from(context);

}
public void setBloglist(ArrayList<QuestionData> data){
    this.data =data;
    notifyItemRangeChanged(0, data.size());
    System.out.print("Size of the array "+data.size());
}
@Override
public ViewQuestion onCreateViewHolder(ViewGroup parent, int viewType) {
    //inflates the customQuestion view or converts it to java code
    View view= mLayoutInflater.inflate(R.layout.customquestion, null);
    //We now want to convert the View into a ViewQuestion, view Question takes
    //a view so we pass the view into view question and then return it.

    ViewQuestion holder=new ViewQuestion(view);
    return holder;
}
//ViewGroup parent and ViewType are not being assigned.
@Override
public void onBindViewHolder(ViewQuestion holder, int position) {
    //here we need to bind the data to our view, there is currently no Data!
    //We need to get the data from our JSON
    //Parameters is a ViewHolder and a Position
    QuestionData currentBlog= data.get(position);
    holder.answerText.setText(currentBlog.getMtext());
    holder.answerId.setText(currentBlog.getId());
    holder.mVotes.setText(currentBlog.getVotes());
    holder.mLikeButton.setTag(currentBlog);
}

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

public class ViewQuestion extends RecyclerView.ViewHolder{
    //once we create it once the reclycer view will automatically recycle it
    private TextView answerText;
    private TextView answerId;
    private TextView mVotes;
    private LikeButton mLikeButton;

    public ViewQuestion (View itemView){
        super(itemView);
        //here we are finding the views by their ID
        answerText=(TextView)itemView.findViewById(R.id.answerText);
        answerId=(TextView)itemView.findViewById(R.id.answerId);
        mVotes=(TextView)itemView.findViewById(R.id.VoteTextView);
        mLikeButton=(LikeButton)itemView.findViewById(R.id.heart_buttons);

        mLikeButton.setOnLikeListener(new OnLikeListener() {
            @Override
            public void liked(LikeButton likeButton) {
                Voting vote = new Voting();
                vote.onUpVote(convertToString(),getAdapterPosition(),ViewQuestion.this);
                  System.out.print("Adapter      Position"+getAdapterPosition());
            }
            @Override
            public void unLiked(LikeButton likeButton) {
                Voting onDown=new Voting();
                onDown.onDownVote(convertToString(), getAdapterPosition(), ViewQuestion.this);

            }
        });

    }
    public String getVoteView(){
        String voteView=mVotes.getText().toString();
        return voteView;
    }
    public String convertToString(){
        String converted=answerId.getText().toString();
        return converted;
    }
    public int convertToInt(){
        String converted=answerId.getText().toString();
        int ConvertedInt=Integer.parseInt(converted);
        return ConvertedInt;
    }
}
}

1.首先，為什么我們將RecyclerView.Adapter擴展為arrayList？ 2. public void setBloglist(ArrayList<QuestionData> data){ this.data =data; notifyItemRangeChanged(0, data.size()); System.out.print("Size of the array "+data.size()); } public void setBloglist(ArrayList<QuestionData> data){ this.data =data; notifyItemRangeChanged(0, data.size()); System.out.print("Size of the array "+data.size()); } public void setBloglist(ArrayList<QuestionData> data){ this.data =data; notifyItemRangeChanged(0, data.size()); System.out.print("Size of the array "+data.size()); }在上面的方法中，我們通過在一個ArrayList，我們該ArrayList的數據設置為傳入的數據，但不我們必須設置在ViewHolder數據？ 3. super(itemView); Why does the ViewHolder extend super? isnt that itself? super(itemView); Why does the ViewHolder extend super? isnt that itself?

Answer 1

1. 它不是ArrayList，而是泛型

2. 此關鍵字指向當前對象，因此我們將AdapterQuestion對象中的數據實例變量的值設置為作為方法爭論傳遞的值

3. ViewHolder不會擴展名為super的類，但是您的ViewQuestion類將擴展RecyclerView.ViewHolder類， super(itemView); 用於調用RecyclerView.ViewHolder構造函數