如图:
1、activity_main.xml
<?xml version="1.0" encoding="utf-8"?> <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" xmlns:app="http://schemas.android.com/apk/res-auto" tools:context=".MainActivity"> <com.google.android.material.tabs.TabLayout android:id="@+id/tab_layout" android:layout_width="wrap_content" android:layout_height="wrap_content" app:tabIndicator="@color/transparent" app:tabRippleColor="@color/transparent" app:tabIndicatorColor="@color/transparent" app:tabBackground="@color/transparent" app:tabIndicatorFullWidth="false" style="@style/CustomTabLayout" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent" app:layout_constraintTop_toTopOf="parent"> </com.google.android.material.tabs.TabLayout> <androidx.viewpager2.widget.ViewPager2 android:id="@+id/view_pager" android:layout_width="0dp" android:layout_height="0dp" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent" app:layout_constraintTop_toBottomOf="@id/tab_layout" app:layout_constraintBottom_toBottomOf="parent"> </androidx.viewpager2.widget.ViewPager2> </androidx.constraintlayout.widget.ConstraintLayout>
2、创建适配器继承 FragmentStateAdapter
package com.example.tablayoutdemo import androidx.fragment.app.Fragment import androidx.fragment.app.FragmentManager import androidx.lifecycle.Lifecycle import androidx.viewpager2.adapter.FragmentStateAdapter class GuideViewPagerAdapter (fragmentManager: FragmentManager, lifecycle: Lifecycle) : FragmentStateAdapter(fragmentManager,lifecycle){ override fun getItemCount(): Int { return 3 } override fun createFragment(position: Int): Fragment { return when (position) { 0 -> { OneFragment() } 1 -> { TwoFragment() } 2 -> { ThreeFragment() } else -> { OneFragment() } } } }
3、MainActivity
package com.example.tablayoutdemo import androidx.appcompat.app.AppCompatActivity import android.os.Bundle import android.util.Log import android.view.LayoutInflater import android.widget.TextView import androidx.constraintlayout.widget.ConstraintLayout import androidx.viewpager2.widget.ViewPager2 import com.google.android.material.tabs.TabLayout import com.google.android.material.tabs.TabLayoutMediator class MainActivity : AppCompatActivity() { private lateinit var guideViewPagerAdapter: GuideViewPagerAdapter override fun onCreate(savedInstanceState: Bundle?) { super.onCreate(savedInstanceState) setContentView(R.layout.activity_main) val tabLayout = findViewById<TabLayout>(R.id.tab_layout) val viewPager = findViewById<ViewPager2>(R.id.view_pager) guideViewPagerAdapter = GuideViewPagerAdapter(supportFragmentManager, lifecycle) viewPager.adapter = guideViewPagerAdapter TabLayoutMediator(tabLayout,viewPager){ tab, position -> val inflater = LayoutInflater.from(tab.parent?.context) val binding = inflater.inflate(R.layout.tab_item_indicator, tab.view, false) Log.i("打印11:","$position") val tvName = binding.findViewById<TextView>(R.id.tv_name) if (position == 0){ tvName.text = "one" tvName.setTextSize(20F) tvName.setBackgroundResource(R.drawable.btn_select) }else if (position == 1){ tvName.text = "two" }else if (position == 2){ tvName.text = "three" } tab.customView = binding }.attach() tabLayout.addOnTabSelectedListener(object : TabLayout.OnTabSelectedListener{ override fun onTabSelected(tab: TabLayout.Tab?) { val customView = tab?.customView as ConstraintLayout val tvName = customView.findViewById<TextView>(R.id.tv_name) tvName.setTextSize(20F) Log.i("打印222:","${tab?.position}") /*if (tab?.position == 0){ tvName.text = "one" }else if (tab!!.position == 1){ tvName.text = "two" }else if (tab!!.position == 2){ tvName.text = "three" }*/ tvName.setBackgroundResource(R.drawable.btn_select) } override fun onTabUnselected(tab: TabLayout.Tab?) { val customView = tab?.customView as ConstraintLayout val tvName = customView.findViewById<TextView>(R.id.tv_name) Log.i("打印333:","${tab?.position}") /* if (tab?.position == 0){ tvName.text = "one" }else if (tab!!.position == 1){ tvName.text = "two" }else if (tab!!.position == 2){ tvName.text = "three" }*/ tvName.setTextSize(16F) tvName.setBackgroundResource(R.drawable.btn_select_no) } override fun onTabReselected(tab: TabLayout.Tab?) { val customView = tab?.customView as ConstraintLayout val tvName = customView.findViewById<TextView>(R.id.tv_name) Log.i("打印444:","${tab?.position}") /*if (tab?.position == 0){ tvName.text = "one" }else if (tab!!.position == 1){ tvName.text = "two" }else if (tab!!.position == 2){ tvName.text = "three" }*/ tvName.setTextSize(18F) tvName.setBackgroundResource(R.drawable.btn_select) } }) } }
4、tab_item_indicator.xml
<?xml version="1.0" encoding="utf-8"?> <androidx.constraintlayout.widget.ConstraintLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="match_parent" android:layout_height="match_parent" xmlns:app="http://schemas.android.com/apk/res-auto"> <TextView android:id="@+id/tv_name" android:layout_width="80dp" android:layout_height="40dp" android:text="" android:gravity="center" android:textSize="16sp" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent" app:layout_constraintTop_toTopOf="parent" app:layout_constraintBottom_toBottomOf="parent"></TextView> <ImageView android:id="@+id/iv_img" android:src="@mipmap/ic_launcher" android:layout_width="40dp" android:layout_height="40dp" app:layout_constraintStart_toStartOf="parent" app:layout_constraintEnd_toEndOf="parent" app:layout_constraintTop_toBottomOf="@id/tv_name"></ImageView> </androidx.constraintlayout.widget.ConstraintLayout>
5、btn_select
<?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle"> <!--填充色--> <!--<solid android:color="#FF409DFE"></solid>--> <solid android:color="#F4F4F4"></solid> <!-- 矩形的边线 --> <!-- <stroke android:color="#4B4B4B" android:width="0.5dp"></stroke>--> <!--圆角大小--> <corners android:bottomRightRadius="20dp" android:topRightRadius="20dp" android:topLeftRadius="20dp" android:bottomLeftRadius="20dp"></corners> <!--android:radius="10dp"--> <!--android:topLeftRadius="7dp" android:bottomLeftRadius="7dp"--> </shape>
6、btn_select_no
<?xml version="1.0" encoding="utf-8"?> <shape xmlns:android="http://schemas.android.com/apk/res/android" android:shape="rectangle"> <!--填充色--> <!--<solid android:color="#FF409DFE"></solid>--> <solid android:color="#FFFFFF"></solid> <!--<!– 矩形的边线 –> <stroke android:color="#4B4B4B" android:width="0.5dp"></stroke>--> <!--圆角大小--> <corners android:bottomRightRadius="20dp" android:topRightRadius="20dp" android:topLeftRadius="20dp" android:bottomLeftRadius="20dp"></corners> <!--android:radius="10dp"--> <!--android:topLeftRadius="7dp" android:bottomLeftRadius="7dp"--> </shape>
7、styles.xml
<?xml version="1.0" encoding="utf-8"?> <resources> <style name="CustomTabLayout" parent="Widget.Design.TabLayout"> <item name="tabGravity">center</item> <item name="tabMode">fixed</item> <item name="tabIndicatorFullWidth">false</item> <item name="android:background">@null</item> <item name="tabIconTint">@null</item> <item name="tabMaxWidth">@dimen/design_tab_max_width</item> <item name="tabIndicatorAnimationDuration">@integer/design_tab_indicator_anim_duration_ms</item> <item name="tabIndicatorColor">@color/transparent</item> <item name="tabIndicatorGravity">bottom</item> <item name="tabIndicatorAnimationMode">linear</item> <item name="tabIndicator">@color/transparent</item> <item name="tabPaddingStart">12dp</item> <item name="tabPaddingEnd">12dp</item> <item name="tabTextAppearance">@style/TextAppearance.Design.Tab</item> <item name="tabTextColor">@null</item> <item name="tabRippleColor">@color/transparent</item> <item name="tabUnboundedRipple">false</item> </style> </resources>
完成