如何在android中加载寻呼机片段时获得选定的选项卡名称

Question

我的所有标签只使用一个片段。 但我无法将选定的选项卡名称传递给我的片段，因此我可以加载我的订单详细信息数据。我在片段中有一个TextView，每当我单击任何选项卡时，我都需要将其文本更改为选项卡名称。 我的代码如下。

在 DateAdapter(PageViewer 适配器)中

public class DateAdapter extends FragmentStatePagerAdapter {
    private Context context;
    int tabCount;
    Integer Index;

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

    public DateAdapter(FragmentManager fm, Context context, int tabCount) {
        super(fm);
        this.context = context;
        this.tabCount = tabCount;
    }

    @Override
    public Fragment getItem(int i) {
        OrderListFragment oneFragment = new OrderListFragment();
        SalesOrderListActivity salesOrderListActivity=new SalesOrderListActivity();
        return oneFragment.newInstance("Tabname", "");
    }

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

    @Override
    public CharSequence getPageTitle(int position) {
        return "Page " + position;
    }

}

在OrderListFragment中（普通片段）

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

        title=(TextView)view.findViewById(R.id.tabtitle);


        salesorderrecycle = (RecyclerView) view.findViewById(R.id.salesorderrecycle);
        salesorderrecycle.setHasFixedSize(true);
        salesorderrecycle.setLayoutManager(new LinearLayoutManager(getActivity()));
        ApiInterface apiInterface = APIClient.getClient().create(ApiInterface.class);
        Call<ArrayList<SalesOrder>> call = apiInterface.GetordersList( loginModel.getUserId());
        call.enqueue(new Callback<ArrayList<SalesOrder>>() {
            @Override
            public void onResponse(Call<ArrayList<SalesOrder>> call, Response<ArrayList<SalesOrder>> response) {
                adapter = new SalesOrderAdapter(getActivity(), response.body());
                adapter.Datefilter("04/09/2019");//Need to give here Tab title value
                salesorderrecycle.setAdapter(adapter);

                ((SalesOrderListActivity)getActivity()).SetCountText(adapter.getItemCount());
                ((SalesOrderListActivity)getActivity()).SetAmountText(adapter.getTotalAmount());
            }
            @Override
            public void onFailure(Call<ArrayList<SalesOrder>> call, Throwable t) {
                Toast.makeText(getActivity(),"Connection Failure",Toast.LENGTH_LONG).show();
            }
        });


        return view;
    }

在 SalesOrderActivity（主要活动）中

public class SalesOrderListActivity extends AppCompatActivity  implements TabLayout.OnTabSelectedListener {


    TextView toolbarText,orderamount,ordercount;
    ImageView back_img;
    public Integer OrderCount;
    public SalesOrderAdapter listadapter;
    TabLayout tablayout;
    ViewPager viewpager;
    public String TabName;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_sales_order_list);
        toolbarText=findViewById(R.id.toolbarText);
        toolbarText.setText("Sale Orders");
        back_img=findViewById(R.id.back_img);
        tablayout=(TabLayout)findViewById(R.id.tablayout);
        viewpager=(ViewPager) findViewById(R.id.viewpager);

        orderamount=findViewById(R.id.orderamount);
        ordercount=findViewById(R.id.ordercount);

        Calendar calendar=Calendar.getInstance();
        Date Today = calendar.getTime();
        SimpleDateFormat df = new SimpleDateFormat("dd MMM \n EEEE");
        String formattedToday = df.format(Today);
        tablayout.addTab(tablayout.newTab().setText(formattedToday));

        for(int i=1;i<=30;i++){
            calendar.add(calendar.DATE,-1);
            Date newDate = calendar.getTime();
            String formattedDate = df.format(newDate);
            tablayout.addTab(tablayout.newTab().setText(formattedDate));
        }

        tablayout.setTabGravity(TabLayout.GRAVITY_FILL);

        DateAdapter adapter=new DateAdapter(getSupportFragmentManager(), this,tablayout.getTabCount());
        viewpager.setAdapter(adapter);
        viewpager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tablayout));
        tablayout.setOnTabSelectedListener(this);



        back_img.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                onBackPressed();
            }
        });
    }

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

        OrderListFragment orderListFragment=new OrderListFragment();
        TabName=tab.getText().toString();
        Toast.makeText(getApplicationContext(),"1st"+TabName,Toast.LENGTH_SHORT).show();
    }

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

    }

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

    }

    public void SetCountText(Integer count){
        ordercount.setText(count.toString());
    }
    public void SetAmountText(Double amt){
        orderamount.setText(String.format("%.2f",amt));
    }

}

Answer 1

适配器类

 import android.support.annotation.Nullable;
 import android.support.v4.app.Fragment;
 import android.support.v4.app.FragmentManager;
 import android.support.v4.app.FragmentStatePagerAdapter;
 import java.util.ArrayList;
 import java.util.List;
 public class TabAdapter extends FragmentStatePagerAdapter {
 List<MyTabFragments> fragmentlist;

public TabAdapter(FragmentManager fm, List<MyTabFragments> fragmentlist ) {
    super(fm);
    this.fragmentlist = fragmentlist;
}

@Override
public Fragment getItem(int position) {

    return fragmentlist.get(position);
}

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

@Override
public CharSequence getPageTitle(int position) {
    return fragmentlist.get(position).getArguments().getString("title");
}
}

片段

import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
public class MyTabFragments extends Fragment {
String title;
public static MyTabFragments getInstances(String title) {
    MyTabFragments ob1 = new MyTabFragments();
    Bundle bundle = new Bundle();
    bundle.putString("title", title);
    ob1.setArguments(bundle);
    ob1.pass(title);
    return  ob1;
}


public void pass(String title) {
    this.title = title;
}

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
    return super.onCreateView(inflater, container, savedInstanceState);
  // You can use title 
}
}

活动类

import android.os.Bundle;
import android.os.PersistableBundle;
import android.support.annotation.Nullable;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import com.podamibe.merolagani.R;
import java.util.ArrayList;
import java.util.List;
public class MyActivity extends AppCompatActivity {
ViewPager viewpage;
@Override
 public void onCreate(@Nullable Bundle savedInstanceState, @Nullable     PersistableBundle persistentState) {
    super.onCreate(savedInstanceState, persistentState);
    setContentView(R.id.your_view);
    viewpage = findViewById(R.id.your_view_pager);
    List<MyTabFragments> fragmentlist = new ArrayList<>();
    MyTabFragments  ob1 =  MyTabFragments.getInstances("Simple title first");
    MyTabFragments  ob2 =  MyTabFragments.getInstances("Simple title Second");
    MyTabFragments  ob3 =  MyTabFragments.getInstances("Simple title third");
    fragmentlist.add(ob1);
    fragmentlist.add(ob2);
    fragmentlist.add(ob3);
    TabAdapter adapter = new TabAdapter(getSupportFragmentManager(), fragmentlist);
    viewpage.setAdapter(adapter);
}
 }

Answer 2

你需要改变你的 DateAdapter 如下

public class DateAdapter extends FragmentStatePagerAdapter {
private Context context;
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();



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

 public void addFragment(Fragment fragment, String title) {
        mFragmentList.add(fragment);
        mFragmentTitleList.add(title);
    }

@Override
public Fragment getItem(int position) {
    return mFragmentList.get(position);
}
@Override
public CharSequence getPageTitle(int position) {
    return mFragmentTitleList.get(position);
}

@Override
public int getCount() {
    return mFragmentList.size;
}
@Override
 public int getItemPosition(Object object) {

    return PagerAdapter.POSITION_NONE;
 }

 public updateTabTittle(int pos, String value){
  mFragmentTitleList.get(pos) = value;
  notifydatasetchanged();
 }
 }

现在你在 viewpager 方法中添加片段也会改变

DateAdapter adapter=new DateAdapter(getSupportFragmentManager());
adapter.addFragment(new OrderListFragment(), "Title for First Fragment" 
);
adapter.addFragment(new OrderListFragment(), "Title for second 
Fragment" ); 
adapter.addFragment(new OrderListFragment(), "Title for third Fragment" 
);  
 viewpager.setAdapter(adapter);

在片段名称更改中创建函数

void change(String str){
textview.setTest(str);
}

并从 SalesOrderActivity 调用此函数 updateTabTittle

 DateAdapter value =  (DateAdapter) adapter.getItem(pos);
 value.change("")


 // pos = fragment postion where you wants to change title