ViewPager2与TabLayout
展示效果
说明:项目必须运行在Androidx环境下使用
依赖
implementation ‘androidx.viewpager2:viewpager2:1.0.0-alpha01’
//tablayout
implementation ‘com.google.android.material:material:1.2.0-alpha01’
一.Activity布局
<LinearLayout 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"
tools:context=".MainActivity"
android:orientation="vertical">
<com.google.android.material.tabs.TabLayout
android:id="@+id/tablayout1"
android:layout_width="match_parent"
android:layout_height="wrap_content">
</com.google.android.material.tabs.TabLayout>
<androidx.viewpager2.widget.ViewPager2
android:id="@+id/v2"
android:layout_width="match_parent"
android:layout_height="match_parent">
</androidx.viewpager2.widget.ViewPager2>
</LinearLayout>
二.Activity代码
public class MainActivity extends AppCompatActivity {
private ViewPager2 viewPager2;
private ArrayList<Fragment> fragments;
private ArrayList<String> titles;
private Fragment1 fragment1;
private Fragment2 fragment2;
private TabLayout tabLayout;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
init();
//设置滑动方向
viewPager2.setOrientation(ViewPager2.ORIENTATION_VERTICAL);
//添加适配器
MyFragmentStateAdapter myFragmentStateAdapter =
new MyFragmentStateAdapter(this,fragments);
viewPager2.setAdapter(myFragmentStateAdapter);
//关联TabLayout 添加attach()
new TabLayoutMediator(tabLayout, viewPager2, new TabLayoutMediator.TabConfigurationStrategy() {
@Override
public void onConfigureTab(@NonNull TabLayout.Tab tab, int position) {
tab.setText(titles.get(position));
}
}).attach();
viewPager2.registerOnPageChangeCallback(new ViewPager2.OnPageChangeCallback() {
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
super.onPageScrolled(position, positionOffset, positionOffsetPixels);
}
@Override
public void onPageSelected(int position) {
super.onPageSelected(position);
Log.d("amy",position+"");
}
@Override
public void onPageScrollStateChanged(int state) {
super.onPageScrollStateChanged(state);
}
});
}
public void init(){
viewPager2 = findViewById(R.id.v2);
tabLayout = findViewById(R.id.tablayout1);
fragments = new ArrayList<>();
fragment1 = new Fragment1();
fragment2 = new Fragment2();
fragments.add(fragment1);
fragments.add(fragment2);//绿
titles = new ArrayList<>();
titles.add("关注");
titles.add("推荐");
}
}
三.适配器
public class MyFragmentStateAdapter extends FragmentStateAdapter {
private ArrayList<Fragment> fragments;
public MyFragmentStateAdapter(@NonNull FragmentActivity fragmentActivity,ArrayList<Fragment> fragments) {
super(fragmentActivity);
this.fragments = fragments;
}
@Override
public int getItemCount() {
return fragments.size();
}
@NonNull
@Override
public Fragment createFragment(int position) {
return fragments.get(position);
}
}