在片段中显示选项卡式菜单

Question

我想在片段中创建一个选项卡式菜单。我试图将片段作为子项包含在mainactivity中，但是它没有用，然后我决定使用JobsTab类包含pageView及其适配器，并以java.lang结尾。 NullPointerException：尝试在空对象引用上调用虚拟方法“ android.view.View android.view.View.findViewById（int）”。谁能帮我解决这个问题

package com.alvartcollection.leakjob.Fragments;

import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;

import androidx.fragment.app.Fragment;
import androidx.viewpager.widget.ViewPager;

import com.alvartcollection.leakjob.PageAdapters.PageAdapter;
import com.alvartcollection.leakjob.R;
import com.google.android.material.tabs.TabLayout;


public class JobsTab extends Fragment {

    private PageAdapter adapter;
    private TabLayout tabLayout;
    private ViewPager viewPager;
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View tabView = inflater.inflate(R.layout.jobstab,container,false);
        viewPager = container.findViewById(R.id.viewPager);
        adapter = new PageAdapter(getFragmentManager());
        adapter.addFragment(new JobsTab(), "Tab 1");
        adapter.addFragment(new MatchedTab(), "Tab 2");
        viewPager.setAdapter(adapter);
        tabLayout.setupWithViewPager(viewPager);
        return tabView;
    }
}