如何按活动添加选项卡项？

Question

我需要的TabLayout有一个“x”的标签数量，这可以根据用户的数据，已经在数据库中有所不同

My xml:在此处输入代码

        <com.google.android.material.tabs.TabItem
            android:id="@+id/posto1"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Posto Shell" />

        <com.google.android.material.tabs.TabItem
            android:id="@id/posto2"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:text="Posto Guanabara" />

我的代码：

select_bar.addOnTabSelectedListener(object : TabLayout.OnTabSelectedListener {
override fun onTabSelected(tab: TabLayout.Tab?) {
            when (tab?.position) {
                0 -> {
                    recycler_view_abastecimentos.adapter =
                        ListaAbastecimentoAdapter(applicationContext, lista)
                }
                1 -> {
                    recycler_view_abastecimentos.adapter =
                        ListaAbastecimentoAdapter(applicationContext, lista)
                }
            }
        }

Answer 1

你可以通过列出清单来实现这一点。从列表中，您可以动态创建选项卡。

例子：

final TabLayout tabLayout = findViewById(R.id.tab_layout);
final ArrayList<Hobby> hobbyList = getHobbyListFromDb();
if (hobbyList.size() > 0) {
   for (int i = 0; i < hobbyList.size(); i++) {
      tabLayout.addTab(tabLayout.newTab().setText(hobbyList.get(i).getName()));
   }
}

Answer 2

 PagerAdapter pagerAdapter = new PagerAdapter(fragmentManager,
        getActivity());

mViewPager.setOffscreenPageLimit(dataCategory.size());

mViewPager.setAdapter(pagerAdapter);

mTabLayout.setupWithViewPager(mViewPager);



class PagerAdapter extends FragmentPagerAdapter {
        Context context;

        PagerAdapter(FragmentManager fm, Context context) {
            super(fm);
            this.context = context;
        }

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

        @Override
        public Fragment getItem(int position) {
            return SubFragment.newInstance(dataCategory.get(position),position, gridType);
         }

        @Override
        public CharSequence getPageTitle(int position) {
            // Generate title based on item position
            // return tabTitles[position];
            return dataCategory.get(position).getCat_Name();
        }

        
    }

Answer 3

你可以这样做：

 TabLayout tabLayout = ...;
 tabLayout.addTab(tabLayout.newTab().setText("Tab 1"));
 tabLayout.addTab(tabLayout.newTab().setText("Tab 2"));
 tabLayout.addTab(tabLayout.newTab().setText("Tab 3"));

请参阅此处的文档：https://developer.android.com/reference/com/google/android/material/tabs/TabLayout