尝试将用户ID从活动发送到Viewholder片段

Question

我创建了一个android应用，其中添加了一个名为profileview.java的活动，用户可以在该活动上查看该活动或其他用户的个人资料数据。 Profileview活动包含两个片段和喜欢的片段，我必须在这些片段上显示用户发布的帖子以及用户喜欢的帖子，但不知道如何将用户ID从Profileview活动发送到其他两个片段。

profileviewactivity.class

 public class profileviewActivity extends AppCompatActivity {
  public String userid;
  private ViewPager viewPager;
  private TabLayout tabLayout;
  private settingtabAdopter Tabadapter;
   protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_profileview);

    viewPager = (ViewPager) findViewById(R.id.viewpager);
    Tabadapter = new settingtabAdopter(getSupportFragmentManager());
    viewPager.setAdapter(Tabadapter);

    tabLayout = (TabLayout) findViewById(R.id.tablayout);
    tabLayout.setupWithViewPager(viewPager);

    userid = getIntent().getExtras().get("userid").toString();
  }
}

settingadapter.java

public class settingtabAdopter extends FragmentPagerAdapter {
public settingtabAdopter(@NonNull FragmentManager fm) {
    super(fm);
}

@NonNull
@Override
public Fragment getItem(int position) {
    switch (position){
        case 0:
            posttimeline postfragment = new posttimeline();
            return postfragment;
        case 1:
            like chatfragment = new like();
            return chatfragment;
        default:
            return null;
    }
}

@Override
public int getCount() {
    return 2;
}

@Nullable
@Override
public CharSequence getPageTitle(int i) {
    switch (i){
        case 0:
            return "Posts";
        case 1:
            return "Likes";
        default:
            return null;
    }
}
}

posttimeline.java

  public class posttimeline extends Fragment {
  View posttimelineview;
   public posttimeline() {
    // Required empty public constructor
}


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
   posttimelineview =  inflater.inflate(R.layout.fragment_posttimeline, container, false);
   return posttimelineview;
  }
}

like.java

 public class like extends Fragment {
 View Likeview;
  public like() {
    // Required empty public constructor
}


@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {
    // Inflate the layout for this fragment
    Likeview = inflater.inflate(R.layout.fragment_like, container, false);
 return Likeview;
}
}

我想将用户ID从profileaviewactivity发送到后时间表和类似片段。

Answer 1

1. [userid作为settingtabAdopter构造函数的参数传递

   public settingtabAdopter(@NonNull FragmentManager fm, String userid) 
   

   profileviewActivity-> onCreate

   Tabadapter = new settingtabAdopter(getSupportFragmentManager(), userid);
   

2. 在settingtabAdopter内设置私有变量

   private String userid;
   

   在构造函数内部初始化

   this.userid = userid
   

3. 在每个片段中创建私有变量并添加setter（后时间线等）片段

   private String mUserid;
   void setMUserId(String mUserid){
       this.mUserid = mUserid;
   }
   

4. 在settingtabAdopter函数内的getItem上初始化每个片段后，用userid设置私有变量

   public Fragment getItem(int position) {
       switch (position){
           case 0:
               posttimeline postfragment = new posttimeline();
               postfragment.setMUserId(userid)
               return postfragment;
           case 1:
               like chatfragment = new like();
               chatfragment.setMUserId(userid)
               return chatfragment;
           default:
               return null;
       }
   }