Android ViewPager Refresh片段

Question

在我的应用程序中有2个选项卡（Android设计支持库）这是带有ViewPagerAdapter的片段：

public class ListaCanali extends Fragment {

public static TabLayout tabLayout;
public static ViewPager viewPager;
public static int int_items = 2 ;

@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    View v =inflater.inflate(R.layout.lista_canali, container,false);

    //Titolo Fragment
    ((MainActivity) getActivity()).setActionBarTitle("Lista Canali");

    //FindViewById
    tabLayout = (TabLayout) v.findViewById(R.id.tabs);
    viewPager = (ViewPager) v.findViewById(R.id.viewpager);

    //Funzioni Tab
    viewPager.setAdapter(new MyAdapter(getChildFragmentManager()));
    tabLayout.post(new Runnable() {
        @Override
        public void run() {
            tabLayout.setupWithViewPager(viewPager);
        }
    });

    return v;
}


//Adattatore Tab
class MyAdapter extends FragmentPagerAdapter {

    public MyAdapter(FragmentManager fm) {
        super(fm);
    }

    @Override
    public Fragment getItem(int position)
    {
        switch (position){
            case 0 : return new FragmentCanali();
            case 1 : return new FragmentPreferiti();
        }
        return null;
    }

    public int getCount() {

        return int_items;

    }

    public CharSequence getPageTitle(int position) {

        switch (position){
            case 0 :
                return "Tutti";
            case 1 :
                return "Preferiti";
        }
        return null;
    }

我希望我的应用程序刷新片段在Swipe上并点击标签标题，因为这不会发生，我希望你能帮助我们。

Answer 1

我相信这不是唯一/最好的方法。 但这应该解决问题，就像它对我做的那样。

请在FragmentCanali和FragmentPreferiti Fragments中编写refresh（）方法。

    public class ListCanali extends Fragment implements OnPageChangeListener{
    private MyAdapter mAdapter;

    @Override
    public View OnCreateView (...) {
    ...
    if(mAdapter == null) {
    mAdapter = new MyAdapter(getChildFragmentManager());
    }
    viewPager.setAdapter(mAdapter);
    viewPager.setOnPageChangeListener(this);
    ...
    }

    ...
    @Override
    public void OnPageSelected (int position) {
    switch (position){
            case 0 : ((FragmentCanali)adapter.getItem(position)).refresh();
            case 1 : ((FragmentPreferiti)adapter.getItem(position)).refresh();
        }
    }}

如果从具有抽象refresh（）方法的基本片段扩展两个片段，它将更加清晰。

在onPageSelected（）中你可以调用((BaseFragment)adapter.getItem(position)).refresh()

Answer 2

尝试这个...

要刷新片段，首先需要它的实例。

改变这一点

 viewPager.setAdapter(new MyAdapter(getChildFragmentManager()));

至

 ArrayList<Fragment> fr_list = new ArrayList<Fragment>();
 fr_list.add(new FragmentCanali());
 fr_list.add(new FragmentPreferiti());
 MyAdapter mMyAdapter = new MyAdapter(getChildFragmentManager(),fr_list);
 viewPager.setAdapter(mMyAdapter);

在适配器中改变这个

 public MyAdapter(FragmentManager fm) {
    super(fm);
}

@Override
public Fragment getItem(int position)
{
    switch (position){
        case 0 : return new FragmentCanali();
        case 1 : return new FragmentPreferiti();
    }
    return null;
}

public int getCount() {

    return int_items;

}

至

 public MyAdapter(FragmentManager fm,ArrayList<Fragment> fr_list) {
    super(fm);
    this.fr_list=fr_list;
}

@Override
public Fragment getItem(int position)
{     
        return fr_list.get(position);
}

public int getCount() {

    return fr_list.size();

}

在片段内添加refresh（）方法，并在需要时调用它

((FragmentCanali) mMyAdapter.fr_list.get(0)).refresh();