วิธีสร้าง Tab Layout ในแอป Android

ภาพรวม

ตัวอย่างนี้สาธิตการสร้าง Tab Layout พร้อม ViewPager โดยใช้ Material Design Support Library แสดง Fragment ต่างๆ ในแต่ละ Tab

ขั้นตอนที่ 1: สร้างโปรเจกต์ใหม่

เปิด Android Studio → File → New Project และกรอกข้อมูลที่จำเป็น

ขั้นตอนที่ 2: เพิ่ม Dependency (build.gradle Module:app)

dependencies {
    implementation 'com.android.support:design:28.0.0'
    // AndroidX ใหม่:
    // implementation 'com.google.android.material:material:1.11.0'
    // implementation 'androidx.viewpager2:viewpager2:1.0.0'
    // implementation 'androidx.fragment:fragment:1.6.2'
}

ขั้นตอนที่ 3: เลย์เอาต์หลัก (res/layout/activity_main.xml)

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="https://schemas.android.com/apk/res/android"
    xmlns:tools="https://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <android.support.design.widget.TabLayout
        android:id="@+id/tabLayout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:background="#1db995" />

    <android.support.v4.view.ViewPager
        android:id="@+id/viewPager"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_below="@id/tabLayout" />

</RelativeLayout>

ขั้นตอนที่ 4: Activity หลัก (src/MainActivity.java)

import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.design.widget.TabLayout;
import android.support.v4.view.ViewPager;

public class MainActivity extends AppCompatActivity {
    TabLayout tabLayout;
    ViewPager viewPager;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        tabLayout = findViewById(R.id.tabLayout);
        viewPager = findViewById(R.id.viewPager);

        // เพิ่ม Tab
        tabLayout.addTab(tabLayout.newTab().setText("Football"));
        tabLayout.addTab(tabLayout.newTab().setText("Cricket"));
        tabLayout.addTab(tabLayout.newTab().setText("NBA"));
        
        tabLayout.setTabGravity(TabLayout.GRAVITY_FILL);

        // Adapter
        MyAdapter adapter = new MyAdapter(this, getSupportFragmentManager(), tabLayout.getTabCount());
        viewPager.setAdapter(adapter);

        // Sync ViewPager กับ TabLayout
        viewPager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tabLayout));
        tabLayout.addOnTabSelectedListener(new TabLayout.OnTabSelectedListener() {
            @Override
            public void onTabSelected(TabLayout.Tab tab) {
                viewPager.setCurrentItem(tab.getPosition());
            }
            @Override public void onTabUnselected(TabLayout.Tab tab) {}
            @Override public void onTabReselected(TabLayout.Tab tab) {}
        });
    }
}

ขั้นตอนที่ 5: Adapter (MyAdapter.java)

import android.content.Context;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.app.FragmentManager;

class MyAdapter extends FragmentPagerAdapter {
    Context context;
    int totalTabs;

    public MyAdapter(Context c, FragmentManager fm, int totalTabs) {
        super(fm);
        context = c;
        this.totalTabs = totalTabs;
    }

    @Override
    public Fragment getItem(int position) {
        switch (position) {
            case 0: return new Football();
            case 1: return new Cricket();
            case 2: return new NBA();
            default: return null;
        }
    }

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

ขั้นตอนที่ 6: สร้าง Fragments

Football.java / fragment_football.xml

// Football.java
public class Football extends Fragment {
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_football, container, false);
    }
}

// fragment_football.xml
<FrameLayout xmlns:android="https://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <TextView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:textAlignment="center"
        android:text="Football Fragment"
        android:textSize="16sp"
        android:textStyle="bold" />
</FrameLayout>

Cricket.java / fragment_cricket.xml

// Cricket.java
public class Cricket extends Fragment {
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_cricket, container, false);
    }
}

// fragment_cricket.xml
<FrameLayout xmlns:android="https://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <TextView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:textAlignment="center"
        android:text="Cricket Fragment"
        android:textSize="16sp"
        android:textStyle="bold" />
</FrameLayout>

NBA.java / fragment_nba.xml

// NBA.java
public class NBA extends Fragment {
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_nba, container, false);
    }
}

// fragment_nba.xml
<FrameLayout xmlns:android="https://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <TextView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:textAlignment="center"
        android:text="NBA Fragment"
        android:textSize="16sp"
        android:textStyle="bold" />
</FrameLayout>

ขั้นตอนที่ 7: AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="https://schemas.android.com/apk/res/android"
    package="app.com.sample">

    <application
        android:allowBackup="true"
        android:icon="@mipmap/ic_launcher"
        android:label="@string/app_name"
        android:roundIcon="@mipmap/ic_launcher_round"
        android:supportsRtl="true"
        android:theme="@style/AppTheme">

        <activity android:name=".MainActivity">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

    </application>
</manifest>

การทดสอบ

รันแอป แท็บ 3 แท็บ สลับได้โดยสไลด์หรือกด Tab

อัปเดตสำหรับ AndroidX + ViewPager2 (แนะนำปัจจุบัน)

Dependencies

dependencies {
    implementation 'com.google.android.material:material:1.11.0'
    implementation 'androidx.viewpager2:viewpager2:1.0.0'
    implementation 'androidx.fragment:fragment:1.6.2'
}

Layout (ใช้ ViewPager2)

<androidx.viewpager2.widget.ViewPager2
    android:id="@+id/viewPager"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:layout_below="@id/tabLayout" />

Adapter ใหม่ (FragmentStateAdapter)

public class MyAdapter extends FragmentStateAdapter {
    public MyAdapter(@NonNull FragmentActivity fa) {
        super(fa);
    }

    @NonNull
    @Override
    public Fragment createFragment(int position) {
        switch (position) {
            case 0: return new Football();
            case 1: return new Cricket();
            case 2: return new NBA();
            default: return new Football();
        }
    }

    @Override
    public int getItemCount() {
        return 3;
    }
}

เชื่อม TabLayout กับ ViewPager2

new TabLayoutMediator(tabLayout, viewPager, (tab, position) -> {
    tab.setText(new String[]{"Football", "Cricket", "NBA"}[position]);
}).attach();

TabLayout Customization

<com.google.android.material.tabs.TabLayout
    android:id="@+id/tabLayout"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    app:tabMode="fixed"              <!-- fixed | scrollable -->
    app:tabGravity="fill"            <!-- fill | center -->
    app:tabIndicatorColor="@color/white"
    app:tabIndicatorHeight="3dp"
    app:tabSelectedTextColor="@color/white"
    app:tabTextColor="@color/gray"
    app:tabTextAppearance="@style/CustomTabText" />