TabLayout使用（切换标签页，结合ViewPager+Fragment）

1引入布局

app:tabMode=“auto” 表示自适应，好用
app:tabMode=“scrollable” 表示滚动，不好用，超过一屏会均分；不超过一屏不均分

app:tabSelectedTextColor="#0371DD" 条目选中时的字体颜色，蓝
app:tabTextColor="#111111" 条目未选中时的字体颜色，黑
app:tabIndicatorColor="#0371DD" tab指示器颜色，蓝
app:tabTextAppearance="@android:style/TextAppearance.Holo.Large" 改变tab字体大小
app:tabIndicatorHeight=“5dp” 改变指示器高度；为0则没有指示器
app:tabContentStart=“100dp” 整个tab距离开始布局的位置的值

tab代码中动态添加 文字
tabLayout.addTab(tabLayout.newTab().setText(“第六个界面”));
添加文字和图片
tabLayout.addTab(tabLayout.newTab().setText(“Tab 1”).setIcon(R.mipmap.ic_launcher));

tabLayout联动viewPager,通过适配器TabAdapter进行关联，TabAdapter关联fragment

TabAdapter adapter = new TabAdapter(this);
        viewPager2 = findViewById(R.id.vp_tb);
        tabLayout = findViewById(R.id.tb_vp);
        viewPager2.setAdapter(adapter);

全代码

package com.example.myapplication.tab;

import androidx.appcompat.app.AppCompatActivity;
import androidx.viewpager2.widget.ViewPager2;

import android.graphics.Color;
import android.os.Bundle;
import android.util.Log;

import com.example.myapplication.R;
import com.google.android.material.tabs.TabLayout;

public class TabActivity extends AppCompatActivity {

    private ViewPager2 viewPager2;
    private TabLayout tabLayout;

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

        TabAdapter adapter = new TabAdapter(this);
        viewPager2 = findViewById(R.id.vp_tb);
        tabLayout = findViewById(R.id.tb_vp);
        viewPager2.setAdapter(adapter);
        //动态控制字体颜色
//        tabLayout.setTabTextColors(Color.parseColor("#111111"),Color.parseColor("#0371DD"));

        adapter.addColor(android.R.color.darker_gray);
        adapter.addColor(android.R.color.holo_red_dark);
        adapter.addColor(android.R.color.holo_green_dark);
        adapter.addColor(android.R.color.holo_blue_dark);
        adapter.addColor(android.R.color.holo_purple);
        adapter.addColor(android.R.color.holo_orange_dark);

        tabLayout.addTab(tabLayout.newTab().setText("第一个界面"));
        tabLayout.addTab(tabLayout.newTab().setText("第二个界面"));
        tabLayout.addTab(tabLayout.newTab().setText("第三个界面"));
        tabLayout.addTab(tabLayout.newTab().setText("第四个界面"));
        tabLayout.addTab(tabLayout.newTab().setText("第五个界面"));
        tabLayout.addTab(tabLayout.newTab().setText("第六个界面"));
        //添加图标
        tabLayout.addTab(tabLayout.newTab().setText("Tab 1").setIcon(R.mipmap.ic_launcher_round));

        tabLayout.addonTabSelectedListener(new TabLayout.onTabSelectedListener() {
            @Override
            public void onTabSelected(TabLayout.Tab tab) {
                viewPager2.setCurrentItem(tab.getPosition());
                Log.e("wy","======我选中了===="+tab.getPosition());
            }

            @Override
            public void onTabUnselected(TabLayout.Tab tab) {
                Log.e("wy","======未被选中===="+tab.getPosition());
            }

            @Override
            public void onTabReselected(TabLayout.Tab tab) {
                Log.e("wy","======再次被选中===="+tab.getPosition());

            }
        });

        viewPager2.registeronPageChangeCallback(new ViewPager2.onPageChangeCallback() {
            @Override
            public void onPageSelected(int position) {
                super.onPageSelected(position);
                tabLayout.setScrollPosition(position, 0, false);
                Log.e("wy", "onPageSelected position: "+position );
            }
        });
    }
}

package com.example.myapplication.tab;

import android.annotation.SuppressLint;
import android.os.Bundle;

import androidx.annotation.NonNull;
import androidx.annotation.Nullable;
import androidx.fragment.app.Fragment;

import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.frameLayout;
import android.widget.TextView;

import com.example.myapplication.R;

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


public class ShowFragment extends Fragment {

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        return inflater.inflate(R.layout.fragment_show, container, false);
    }

    static ShowFragment newInstance(List colors, int item) {
        Bundle bundle = new Bundle();
        bundle.putSerializable("color", (ArrayList) colors);
        bundle.putInt("item", item);
        ShowFragment fragment = new ShowFragment();
        fragment.setArguments(bundle);
        return fragment;
    }

    @SuppressLint("SetTextI18n")
    @Override
    public void onViewCreated(@NonNull View view, @Nullable Bundle savedInstanceState) {
        view.findViewById(R.id.fl_show)
                .setBackgroundResource(((ArrayList) getArguments()
                        .getSerializable("color")).get(getArguments().getInt("item")));
        view.findViewById(R.id.tv_show).setText("第 " + (getArguments().getInt("item") + 1) + " 个页面");
        super.onViewCreated(view, savedInstanceState);
    }

}

fragment_show.xml