Tablayout title aren't visible in Android

问题

As the title explain, I am not able to see the title in the tablayout. I have followed a tutorial on youtube to create this swipable tabs. Here the link of the tutorial

I have followed all the instruction shown in the video but I couldn't get the similar results.

Here is my code

MainActivity.class

package com.example.kuro.bloodpressure;

import android.annotation.TargetApi;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.os.Build;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.design.widget.TabLayout;
import android.support.v4.view.ViewPager;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.ImageView;
import android.app.Fragment;

public class MainActivity extends AppCompatActivity {
    public Toolbar toolbar;
    public TabLayout tabLayout;
    public ViewPager viewPager;
    public ViewPagerAdapter viewPagerAdapter;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        tabLayout = (TabLayout)findViewById(R.id.tablayout);
        viewPager = (ViewPager)findViewById(R.id.viewpager);
        viewPagerAdapter = new ViewPagerAdapter(getSupportFragmentManager());
        viewPagerAdapter.addFragments(new Measure(), "MEASURE");
        viewPagerAdapter.addFragments(new People(), "PEOPLE");
        viewPager.setAdapter(viewPagerAdapter);
        tabLayout.setupWithViewPager(viewPager);

    }


    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.menu_main, menu);
        return true;
    }

    @TargetApi(Build.VERSION_CODES.LOLLIPOP)
    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {
            case R.id.add_person:
                AlertDialog.Builder add_people_form = new AlertDialog.Builder(MainActivity.this);
                add_people_form.setView(R.layout.add_form)
                        .setCancelable(false)
                        .setPositiveButton("DONE", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                finish();
                            }
                        })
                        .setNegativeButton("CANCLE", new DialogInterface.OnClickListener() {
                            @Override
                            public void onClick(DialogInterface dialog, int which) {
                                dialog.cancel();
                            }
                        });
                AlertDialog alert = add_people_form.create();
                alert.show();
                return true;
            default:
                return super.onOptionsItemSelected(item);
        }
    }

}

activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout 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:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true"
    tools:context="com.example.kuro.bloodpressure.MainActivity">

    <android.support.design.widget.AppBarLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">

        <include
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            layout="@layout/toolbar"
            />
        <android.support.design.widget.TabLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            app:tabMode="fixed"
            app:tabGravity="fill"
            app:tabTextAppearance="@style/MyTabText"
            android:id="@+id/tablayout">

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

    </android.support.design.widget.AppBarLayout>
    <android.support.v4.view.ViewPager
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/viewpager">

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

   <!--<include layout="@layout/content_main"/>-->

    <!--<android.support.design.widget.FloatingActionButton-->
        <!--android:id="@+id/fab"-->
        <!--android:layout_width="wrap_content"-->
        <!--android:layout_height="wrap_content"-->
        <!--android:layout_gravity="bottom|end"-->
        <!--android:layout_margin="@dimen/fab_margin"-->
        <!--android:src="@android:drawable/ic_dialog_email" />-->

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

ViewPagerAdapter.class

package com.example.kuro.bloodpressure;

import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.View;

import java.util.ArrayList;

/**
 * Created by Kuro on 4/16/2016.
 */
public class ViewPagerAdapter extends FragmentPagerAdapter {
    ArrayList<Fragment> fragments = new ArrayList<>();
    ArrayList<String> tabTitles = new ArrayList<>();

    public void addFragments(Fragment fragment, String title) {
        this.fragments.add(fragment);
        this.tabTitles.add(title);

    }

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

    @Override
    public Fragment getItem(int position) {

        return fragments.get(position);
    }

    @Override
    public int getCount() {

        return fragments.size();
    }

    public String getPageTitles(int position) {

        return tabTitles.get(position);
    }
}

toolbar.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.Toolbar
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:background="@color/colorPrimary"
    android:minHeight="?attr/actionBarSize"
    android:fitsSystemWindows="true"
    android:id="@+id/toolbar"
    app:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar"
    >

</android.support.v7.widget.Toolbar>

style.xml

<resources>

    <!-- Base application theme. -->
    <style name="AppTheme" parent="Theme.AppCompat.Light.NoActionBar">
        <!-- Customize your theme here. -->
        <item name="colorPrimary">@color/colorPrimary</item>
        <item name="colorPrimaryDark">@color/colorPrimaryDark</item>
        <item name="colorAccent">@color/colorAccent</item>
    </style>

    <style name="MyEditTextTheme">
        <!-- Used for the bottom line when not selected / focused -->
        <item name="colorControlNormal">#98ffffff</item>
        <item name="android:colorControlActivated">#ffffff</item>
        <!-- colorControlActivated & colorControlHighlight use the colorAccent color by default -->
    </style>

    <style name="AppTheme.NoActionBar">
        <item name="windowActionBar">false</item>
        <item name="windowNoTitle">false</item>
    </style>

    <style name="AppTheme.AppBarOverlay" parent="ThemeOverlay.AppCompat.Dark.ActionBar" />

    <style name="AppTheme.PopupOverlay" parent="ThemeOverlay.AppCompat.Light" />

    <style name="MyTabText" parent="@android:style/Widget.Holo.Light.ActionBar.TabText">
        <item name="android:textColor">#fff</item>
    </style>

</resources>

回答1:

In your activity_main.xml, add this line to your ViewPager :

<android.support.v4.view.ViewPager
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/viewpager"app:layout_behavior="android.support.design.widget.AppBarLayout$ScrollingViewBehavior">
</android.support.v4.view.ViewPager>

The reason for that is since you use a Coordinator layout, you need to provide which view it should react to. In this case, your ViewPager

EDIT : It also seems that your Adapter doesn't implement the required function for titles :

    @Override
    public CharSequence getPageTitle(int position) {
        return tabTitles.get(position);
    }

来源：https://stackoverflow.com/questions/36675884/tablayout-title-arent-visible-in-android

标签

android

xml

android-tablayout