Question

在这个布局中，我已经使用片段活动制作了标签布局，并希望显示一些内容，但片段活动中没有显示任何内容。这是基础xml，其中片段是change.xml

<android.support.v4.widget.DrawerLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_change"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    app:layout_collapseParallaxMultiplier="0.5"
    tools:context="com.example.alpit.formula2.Change">

    <RelativeLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <android.support.design.widget.AppBarLayout
            android:id="@+id/change_appbar"
            android:layout_width="match_parent"
            android:layout_height="wrap_content">

            <android.support.v7.widget.Toolbar
                android:id="@+id/change"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:background="?attr/colorPrimary"
                app:popupTheme="@style/AppTheme.NoActionBar.PopupOverlay"></android.support.v7.widget.Toolbar>

            <android.support.design.widget.TabLayout
                android:id="@+id/change_tab"
                android:layout_width="match_parent"
                android:layout_height="?attr/actionBarSize"
                app:tabGravity="fill">

            </android.support.design.widget.TabLayout>


        </android.support.design.widget.AppBarLayout>

        <android.support.v4.view.ViewPager
            android:id="@+id/change_viewpager"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_below="@id/change_appbar"
            app:layout_behavior="@string/appbar_scrolling_view_behavior">

        </android.support.v4.view.ViewPager>
    </RelativeLayout>

    <android.support.design.widget.NavigationView
        android:id="@+id/nav_change"
        android:layout_width="wrap_content"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        app:menu="@menu/navigation_menu"
        app:theme="@style/NavigationTheme">

    </android.support.design.widget.NavigationView>
</android.support.v4.widget.DrawerLayout>

这是标签布局的java代码

 import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;


public class Distance extends Fragment {


    protected View onCreate(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        return inflater.inflate(R.layout.activity_distance, container, false);
    }
}

这是距离的xml代码

  <?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/activity_distance"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
    tools:context="com.example.alpit.formula2.Distance"

    >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="10dp"
        android:text="Weight in kg" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="10dp"
        android:text="Weight in kg" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="10dp"
        android:text="Weight in kg"
        android:textSize="100sp" />

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:padding="10dp"
        android:text="Weight in kg" />


</LinearLayout>

这是我在布局中添加标签的java代码

import android.os.Bundle;
import android.support.design.widget.NavigationView;
import android.support.design.widget.TabLayout;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.MenuItem;

import java.util.ArrayList;
import java.util.List;


class Change extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener {
    private ActionBarDrawerToggle toggle3;
    private ViewPager viewPager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_change);
        Toolbar toolbar = (Toolbar) findViewById(R.id.change);
        setSupportActionBar(toolbar);
        DrawerLayout drawerLayout = (DrawerLayout) findViewById(R.id.activity_change);
        toggle3 = new ActionBarDrawerToggle(this, drawerLayout, R.string.open, R.string.Close);
        drawerLayout.addDrawerListener(toggle3);
        toggle3.syncState();
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
        NavigationView navigationView = (NavigationView) findViewById(R.id.nav_change);
        navigationView.setItemIconTintList(null);
        navigationView.setNavigationItemSelectedListener(this);
        setTitle("Conversion");
        viewPager = (ViewPager) findViewById(R.id.change_viewpager);
        setUpViewpager(viewPager);
        TabLayout tabs = (TabLayout) findViewById(R.id.change_tab);
        tabs.setupWithViewPager(viewPager);


    }

    public boolean onOptionsItemSelected(MenuItem menuItem) {
        if (toggle3.onOptionsItemSelected(menuItem)) {
            return true;
        }
        return onOptionsItemSelected(menuItem);
    }

    private void setUpViewpager(ViewPager upViewpager) {
        Adapter_tab adapter = new Adapter_tab(getSupportFragmentManager());
        adapter.addFragment(new Distance(), "Distance");
        adapter.addFragment(new Mass(), "Mass");
        upViewpager.setAdapter(adapter);

    }


    @Override
    public boolean onNavigationItemSelected(MenuItem item) {
        return false;
    }

    static class Adapter_tab extends FragmentPagerAdapter {
        private final List<Fragment> mFragmentList = new ArrayList<>();
        private final List<String> mFragmentTitleList = new ArrayList<>();

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

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

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

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

        public CharSequence getPageTitle(int position) {
            return mFragmentTitleList.get(position);
        }


    }
}

Answer 1

只需在距离

中添加onCreateView即可

片段布局没有显示任何内容？

1 个答案: