我正在使用ViewPager来左右滑动页面,我已经添加了选项卡。选项卡的数目取决于服务器数据,所以我不能将选项卡数量固定下来。为此,我只使用了单个Fragment和一个RecyclerView来在RecyclerView中显示JSON数据。当应用程序首次启动时,应该显示在第二个选项卡中的数据实际上被显示在了第一个选项卡中。当我向右滑动到第三个选项卡并再次返回到第一个选项卡时,数据才会正确地显示。
这与GooglePlayStore相同。我认为只有一个Fragment,因为所有选项卡的UI都是相同的。
以下是添加Fragment并在RecyclerView中显示数据的代码。
PagerAdapter.java
这与GooglePlayStore相同。我认为只有一个Fragment,因为所有选项卡的UI都是相同的。
以下是添加Fragment并在RecyclerView中显示数据的代码。
PagerAdapter.java
private class PagerAdapter extends FragmentStatePagerAdapter {
int mNumOfTabs;
List<List<ProductInfo>> data;
public PagerAdapter(FragmentManager fm, int NumofTabs, List<List<ProductInfo>> data) {
super(fm);
mNumOfTabs = NumofTabs;
this.data = data;
}
@Override
public Fragment getItem(int position) {
/* ProductFragment pf = ProductFragment.newInstance(data.get(position),position);
return pf;*/
return ProductFragment.newInstance(data.get(position),0);
}
@Override
public int getCount() {
return mNumOfTabs;
}
}
Fragment.java
public class ProductFragment extends Fragment {
private static final String ARG_PRODUCTS = "PRODS";
private static List<ProductInfo> allProducts;
int position = 0;
RecyclerView prodList;
public static ProductFragment newInstance(List<ProductInfo> products,int position) {
ProductFragment fragment = new ProductFragment();
Bundle args = new Bundle();
args.putParcelableArrayList(ARG_PRODUCTS, (ArrayList<ProductInfo>) products);
args.putInt("KEY_POSITION",position);
args.putInt("KEY_ID",id);
fragment.setArguments(args);
return fragment;
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//if(isVisibleToUser){
if (getArguments() != null) {
allProducts = getArguments().getParcelableArrayList(ARG_PRODUCTS);
this.position = getArguments().getInt("KEY_POSITION");
}
// }
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View view = inflater.inflate(R.layout.fragment_product, container, false);
prodList = (RecyclerView) view.findViewById(R.id.product_list);
return view;
}
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
prodList.setLayoutManager(new LinearLayoutManager(getActivity()));
prodList.setAdapter(new ProductAdapter(getActivity(), allProducts));
Log.e("ProductFragment " ,"" + allProducts.get(position).getName());
}
EDITED: Activity.java
onCreate(){
TabLayout tabLayout = (TabLayout) findViewById(R.id.tab_layout);
allProducts = new ArrayList<>();
for (Category cat : catList) {
tabLayout.addTab(tabLayout.newTab().setText(cat.getName()));
tabLayout.setTabMode(TabLayout.MODE_SCROLLABLE);
//tabLayout.setTabGravity(TabLayout.GRAVITY_FILL);
allProducts.add(cat.getProductsList());
}
viewPager = (ViewPager) findViewById(R.id.pager);
adapter = new PagerAdapter
(getSupportFragmentManager(), tabLayout.getTabCount(), allProducts);
viewPager.setOffscreenPageLimit(0);
viewPager.setAdapter(adapter);
viewPager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tabLayout));
tabLayout.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
@Override
public void onTabSelected(TabLayout.Tab tab) {
Log.e("ViewPager "," getCurrentItem() "+viewPager.getCurrentItem());
viewPager.setCurrentItem(tab.getPosition());
}
@Override
public void onTabUnselected(TabLayout.Tab tab) {
}
@Override
public void onTabReselected(TabLayout.Tab tab) {
}
});
}
输入图像描述: