Question

我的recycleview个应用可以显示随机页面吗？我想在我的floatbutton上添加detailactivity.javaclass，当我点击它时，必须显示包含我的字符串数据和图像文件的页面。

mFlowerData = new FlowerData("Rose", getString(R.string.description_flower_rose),
            R.drawable.rose);
mFlowerList.add(mFlowerData);
mFlowerData = new FlowerData("Carnation", getString(R.string.description_flower_carnation),
            R.drawable.carnation);

如何在最后一页上显示它。

Answer 1

你可以在你的活动/片段中使用这样的东西

private List<Simple> elements;

private String names[] = {
        "Monk's Oartormow",
        "Eldoth Nut",
        "Eblurst",
        "Poison Okule",
        "Black Berry",
        "Snake Eye",
        "Witch's Root",
        "White Burm",
        "Yellow Pig Claw",
        "Uchea Mint"
};

private String contents[] = {
        "What if the adaptable injury ate the click?",
        "The united chip stuffs into the babyish sad.",
        "Did the interesting progress really argue the visual?",
        "What if the chief sign ate the schedule?",
        "Is the brush respect better than the raise?",
        "It was then the inexperienced topic met the open period."
};


@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_flower);
    Toolbar toolbar = findViewById(R.id.toolbar);
    setSupportActionBar(toolbar);

    elements = new ArrayList<>();

    adapter = new SimpleAdapter();

    RecyclerView recyclerView = findViewById(R.id.recycler_view);
    recyclerView.setLayoutManager(new LinearLayoutManager(this));
    recyclerView.setAdapter(adapter);

    FloatingActionButton fab = findViewById(R.id.fab);
    fab.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            Simple s = generateRandomElement();
            elements.add(0,s);
            adapter.updateElements(elements);
        }
    });
}

private Simple generateRandomElement() {
    int posNames = (int) (Math.random() * names.length);
    int posContent = (int) (Math.random() * contents.length);
    String name = names[posNames];
    String content = contents[posContent];

    return new Simple(name, content);
}

并更新适配器中的元素：

private List<Simple> elements;

public SimpleAdapter() {
    this.elements = new ArrayList<>();
}

@Override
public SimpleViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
    View view = LayoutInflater.from(parent.getContext())
            .inflate(R.layout.row_simple_element, parent, false);
    return new SimpleViewHolder(view);
}

@Override
public void onBindViewHolder(SimpleViewHolder holder, int position) {
    Simple element = elements.get(position);
    holder.title.setText(element.getTitle());
    holder.content.setText(element.getContent());
}

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

public void updateElements(List<Simple> elements) {
    this.elements.clear();
    this.elements.addAll(elements);
    notifyDataSetChanged();
}

您可以改善为Flower类实现DiffCallback的元素更新方式（link）

在recycleview上显示随机页面

1 个答案: