从RecyclerView.Adapter类

Question

是否可以通过RecyclerView.Adapter类更新某些列表数据

这是我的List类：

public class Idea {
    private String id, name, voted;

    public Idea(String id, String name, String voted) {
        this.id = id;
        this.name = name;
        this.voted = voted;
    }

    public String getId() {
        return id;
    }

    public String getName() {
        return name;
    }

    public String getVoted() {
        return voted;
    }
}

我的RecyclerView适配器类：

public class IdeaListAdapter extends RecyclerView.Adapter<IdeaListAdapter.IdeaViewHolder> {

    private Context mCtx;
    private List<Idea> ideaList, idlst;

    public IdeaListAdapter(Context mCtx, List<Idea> ideaList) {
        this.mCtx = mCtx;
        this.ideaList = ideaList;
    }

    @NonNull
    @Override
    public IdeaListAdapter.IdeaViewHolder onCreateViewHolder(@NonNull ViewGroup viewGroup, int i) {
        LayoutInflater inflater = LayoutInflater.from(mCtx);
        View view = inflater.inflate(R.layout.idea_list_object_layout, null);
        return new IdeaListAdapter.IdeaViewHolder(view);
    }

    @Override
    public void onBindViewHolder(@NonNull IdeaListAdapter.IdeaViewHolder ideaViewHolder, int i) {
        final Idea idea = ideaList.get(i);

        if (idea.getVoted().equals("0")) {
            ideaViewHolder.checkBoxLikeIdeaListFragment.setChecked(false);
        } else if (idea.getVoted().equals("1")) {
            ideaViewHolder.checkBoxLikeIdeaListFragment.setChecked(true);
        }

        ideaViewHolder.checkBoxLikeIdeaListFragment.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton compoundButton, boolean b) {
                if (b) {
                    *** Update my idea.getVoted() here ***
                } else {
                    *** Update my idea.getVoted() here ***
                }
            }
        });
        ideaViewHolder.textViewNameIdeaListFragment.setText(idea.getName());

    }

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

    class IdeaViewHolder extends RecyclerView.ViewHolder {

        TextView textViewNameIdeaListFragment;
        CheckBox checkBoxLikeIdeaListFragment;

        public IdeaViewHolder(@NonNull View itemView) {
            super(itemView);

            textViewNameIdeaListFragment = (TextView) itemView.findViewById(R.id.textViewNameIdeaListFragment);
            checkBoxLikeIdeaListFragment = (CheckBox) itemView.findViewById(R.id.checkBoxLikeIdeaListFragment);
        }
    }

}

当用户单击 checkBoxLikeIdeaListFragment 时，我想更新我的idea.getVoted（） 我不太确定我将如何在此部分使用 ideaList.set（） 。

我应该在我的 MainActivity 上执行此操作吗？如果是，请教我。

Answer 1

在模型类**Idea**上创建Setter方法，并访问setter方法以更新数据。

喜欢这个。

public class Idea {
    private String id, name, voted;

    public Idea(String id, String name, String voted) {
        this.id = id;
        this.name = name;
        this.voted = voted;
    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getVoted() {
        return voted;
    }

    public void setVoted(String voted) {
        this.voted = voted;
    }
}

在适配器类中使用setVoted的setter方法。

ideaViewHolder.checkBoxLikeIdeaListFragment.setOnCheckedChangeListener(
            new CompoundButton.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(CompoundButton compoundButton, boolean b) {
            i
            ideaList.get(i).setVoted("set your data"); //here you have to upadte the vote value.
            notifiyDatasetChanged(); 
        }
    });

Answer 2

最快的方法是在OnCheckedListener构造函数上传递IdeaViewHolder并将其分配给checkBoxLikeIdeaListFragment。

或者在您现有的代码上，您可以：

ideaViewHolder.checkBoxLikeIdeaListFragment.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
            @Override
            public void onCheckedChanged(CompoundButton compoundButton, boolean b) {
                   ideaList.get(i).setVoted(b); // i is the int index passed to onBindViewHolder(..)
                  IdeaListAdapter.this.notifyDatasetChanged(); //update list 


            }
        });