Question

我在mainActivity中有一个TabLayout，有一些标签，标签是片段在每个片段上我都有一个ReclerView 从主活动我想在我的片段中的我的适配器上调用notifyDatasetChange()来更新UI 但是如何通知呢？

myMainActivity：

     final ViewPager viewPager = (ViewPager) findViewById(R.id.viewPager);


    TabLayout     tabLayout = (TabLayout) findViewById(R.id.tabLayout);
    tabLayout.addTab(tabLayout.newTab().setText("Tab1"));
    tabLayout.addTab(tabLayout.newTab().setText("Tab2"));


    final PagerAdapter adapter = new PagerAdapter
            (getSupportFragmentManager(), tabLayout.getTabCount());
    viewPager.setAdapter(adapter);
    viewPager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tabLayout));
    tabLayout.setOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
        @Override
        public void onTabSelected(TabLayout.Tab tab) {
            viewPager.setCurrentItem(tab.getPosition());
        }

        @Override
        public void onTabUnselected(TabLayout.Tab tab) {

        }

        @Override
        public void onTabReselected(TabLayout.Tab tab) {

        }
    });

myTabFragment之一：

 @Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    RecyclerView v = (RecyclerView) inflater.inflate(R.layout.tab_fragment_1, container, false);
    SetupRecycleView(v);
    return v;
}


void SetupRecycleView(RecyclerView recList) {
    recList.setHasFixedSize(true);
    LinearLayoutManager llm = new LinearLayoutManager(G.context);
    llm.setOrientation(LinearLayoutManager.VERTICAL);
    //recList.setLayoutManager(new GridLayoutManager(G.context, 2));
    recList.setLayoutManager(llm);
    List<StructGhaza> ghazas = StructGhaza.getAllGhaza("2");
    CardAdapter adapter = new CardAdapter(ghazas);
    recList.setAdapter(adapter);
}

CardAdapter：

public class CardAdapter extends     RecyclerView.Adapter<CardAdapter.GhazaViewHolder> {

private List<StructGhaza> ghazas;

public CardAdapter(List<StructGhaza> ghazaList) {
    this.ghazas = ghazaList;
}

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

@Override
public void onBindViewHolder(GhazaViewHolder ghazaViewHolder, int position) {

    StructGhaza ghaza = ghazas.get(position);
    ghazaViewHolder.vTitle.setText(ghaza.Name);
    //----Load Image
    Glide.with(G.context)
            .load(ghaza.Aks)
            .placeholder(R.drawable.loading_spinner)
            .crossFade()
            .into(ghazaViewHolder.itemImg);
    //---------------
    ghazaViewHolder.Rate.setRating(ghaza.Star);
    ghazaViewHolder.sampleLayout.setHoverView(ghazaViewHolder.hover);
    ghazaViewHolder.sampleLayout.addChildAppearAnimator(ghazaViewHolder.hover, R.id.tvHover, Techniques.FlipInX);
    ghazaViewHolder.sampleLayout.addChildDisappearAnimator(ghazaViewHolder.hover, R.id.tvHover, Techniques.FlipOutX);
}

@Override
public GhazaViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
    View itemView = LayoutInflater.
            from(viewGroup.getContext()).
            inflate(R.layout.fragment_carditem, viewGroup, false);

    return new GhazaViewHolder(itemView);
}

public static class GhazaViewHolder extends RecyclerView.ViewHolder {
    protected TextView vTitle;
    protected BlurLayout sampleLayout;
    protected View hover;
    protected ImageView itemImg;
    protected RatingBar Rate;

    public GhazaViewHolder(View v) {
        super(v);
        sampleLayout = (BlurLayout) v.findViewById(R.id.sample);
        itemImg = (ImageView) v.findViewById(R.id.item_img);
        hover = LayoutInflater.from(G.context).inflate(R.layout.fragment_hover, null);
        vTitle = (TextView) v.findViewById(R.id.titleTv);
        Rate = (RatingBar) v.findViewById(R.id.rating);
    }
}
}

Answer 1

我建议您在Fragment中使用公开方法，然后从Activity拨打电话。请参阅＆＃34;向片段发送消息＆＃34;在这里：

http://developer.android.com/training/basics/fragments/communicating.html

在Activity中，只需执行以下操作即可确保可以调用Fragment方法：

    TabFragment tabFragment = (TabFragment) getSupportFragmentManager().findFragmentByTag(TAB_FRAGMENT_TAG);

        // Check if the tab fragment is available
        if (tabFragment != null) {

            // Call your method in the TabFragment
            articleFrag.yourMethod();
    }

然后在Fragment中，使用以下方法：

    public void yourMethod() { 
        recyclerViewAdapter.notifyDataSetChanged(); 
    }

Answer 2

在片段中创建updateListview（），如

public void updateListView() {
    yourAdapter.notifyDataSetChanged();
}

您的活动中的

和updateListview（）

updateListView();

如何通过活动通知片段中的适配器？

2 个答案: