GridView分頁顯示與數(shù)據(jù)過濾

在Android開發(fā)中，GridView是一種常用的列表視圖控件，用于展示大量數(shù)據(jù)。為了提高性能和用戶體驗，我們通常需要對GridView進(jìn)行分頁顯示和數(shù)據(jù)過濾。下面是一個簡單的示例，展示了如何實現(xiàn)GridView的分頁顯示和數(shù)據(jù)過濾。

1. 首先，創(chuàng)建一個數(shù)據(jù)源，例如一個ArrayList，用于存儲要顯示的數(shù)據(jù)。

List<String> dataList = new ArrayList<>();
for (int i = 1; i <= 20; i++) {
    dataList.add("Item " + i);
}

2. 創(chuàng)建一個適配器，繼承自BaseAdapter，用于將數(shù)據(jù)綁定到GridView。

public class MyAdapter extends BaseAdapter {
    private List<String> dataList;
    private Context context;

    public MyAdapter(Context context, List<String> dataList) {
        this.context = context;
        this.dataList = dataList;
    }

    @Override
    public int getCount() {
        return dataList.size();
    }

    @Override
    public Object getItem(int position) {
        return dataList.get(position);
    }

    @Override
    public long getItemId(int position) {
        return position;
    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {
        if (convertView == null) {
            convertView = LayoutInflater.from(context).inflate(R.layout.item_layout, parent, false);
        }
        TextView textView = convertView.findViewById(R.id.text_view);
        textView.setText(dataList.get(position));
        return convertView;
    }
}

3. 在Activity中，初始化GridView和適配器，并設(shè)置適配器。

public class MainActivity extends AppCompatActivity {
    private GridView gridView;
    private MyAdapter adapter;
    private List<String> dataList;
    private int currentPage = 1;
    private final int pageSize = 5;

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

        gridView = findViewById(R.id.gridview);
        dataList = new ArrayList<>();
        // 填充數(shù)據(jù)
        for (int i = 1; i <= 20; i++) {
            dataList.add("Item " + i);
        }

        adapter = new MyAdapter(this, dataList);
        gridView.setAdapter(adapter);

        // 設(shè)置分頁監(jiān)聽器
        gridView.setOnScrollListener(new AbsListView.OnScrollListener() {
            @Override
            public void onScrollStateChanged(AbsListView view, int scrollState) {
            }

            @Override
            public void onScroll(AbsListView view, int firstVisibleItem, int visibleItemCount, int totalItemCount) {
                if (firstVisibleItem + visibleItemCount >= totalItemCount && !isLoadingMore) {
                    isLoadingMore = true;
                    currentPage++;
                    loadMoreData();
                }
            }
        });
    }

    private void loadMoreData() {
        // 模擬異步加載數(shù)據(jù)
        new Handler().postDelayed(new Runnable() {
            @Override
            public void run() {
                List<String> newData = new ArrayList<>();
                for (int i = (currentPage - 1) * pageSize + 1; i <= currentPage * pageSize; i++) {
                    newData.add("Item " + i);
                }
                dataList.addAll(newData);
                adapter.notifyDataSetChanged();
                isLoadingMore = false;
            }
        }, 1000);
    }
}

4. 為了實現(xiàn)數(shù)據(jù)過濾，可以在適配器中添加一個方法，用于根據(jù)輸入的搜索關(guān)鍵詞過濾數(shù)據(jù)。

public void filterData(String keyword) {
    List<String> filteredList = new ArrayList<>();
    for (String item : dataList) {
        if (item.contains(keyword)) {
            filteredList.add(item);
        }
    }
    dataList = filteredList;
    notifyDataSetChanged();
}

在Activity中，可以為搜索框設(shè)置一個監(jiān)聽器，當(dāng)用戶輸入關(guān)鍵詞時，調(diào)用適配器的filterData方法進(jìn)行數(shù)據(jù)過濾。

searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
    @Override
    public boolean onQueryTextSubmit(String query) {
        return false;
    }

    @Override
    public boolean onQueryTextChange(String newText) {
        adapter.filterData(newText);
        return true;
    }
});

這樣，我們就實現(xiàn)了一個簡單的GridView分頁顯示和數(shù)據(jù)過濾功能。你可以根據(jù)實際需求進(jìn)行調(diào)整和優(yōu)化。