XYLibrary笔记六：XTab使用笔记

import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
import android.support.design.widget.TabLayout;
import java.util.List;

public class XTab {
    public static void addTab(TabLayout tabLayout,
                              ViewPager viewPager,
                              final List<Fragment> fragment,
                              final List<String> title,
                              FragmentManager fragmentManager,
                              int offscreenPageLimit,
                              onPageSelected onPageSelected){
        /**
         * 预加载
         */
        viewPager.setOffscreenPageLimit(offscreenPageLimit);
        viewPager.setAdapter(new FragmentPagerAdapter(fragmentManager) {
            @Override
            public Fragment getItem(int position) {
                return fragment.get(position);
            }
            @Override
            public int getCount() {
                return fragment.size();
            }
            @Override
            public CharSequence getPageTitle(int position) {
                return title.get(position);
            }
        });
        viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
            @Override
            public void onPageScrolled(int i, float v, int i1) {}

            @Override
            public void onPageSelected(int i) {
                onPageSelected.onPageSelected(i);}

            @Override
            public void onPageScrollStateChanged(int i) {
            }
        });
        // TabLayout关联ViewPager
        tabLayout.setupWithViewPager(viewPager);
    }
    public interface onPageSelected{
        void onPageSelected(int position);
    }
}

import androidx.appcompat.app.AppCompatActivity;
import androidx.fragment.app.Fragment;
import androidx.fragment.app.FragmentManager;
import androidx.fragment.app.FragmentPagerAdapter;
import androidx.viewpager.widget.ViewPager;
import com.google.android.material.tabs.TabLayout;

...

...
    <android.support.design.widget.TabLayout
        android:layout_width="match_parent"
        app:tabGravity="fill"
        app:tabMode="fixed"
        android:layout_height="wrap_content">
    </android.support.design.widget.TabLayout>

    <android.support.v4.view.ViewPager
        android:layout_width="match_parent"
        android:layout_height="match_parent"/>
...

...
    <com.google.android.material.tabs.TabLayout
        android:layout_width="match_parent"
        app:tabGravity="fill"
        app:tabMode="fixed"
        android:id="@+id/_tab"
        android:layout_height="wrap_content">
    </com.google.android.material.tabs.TabLayout>

    <androidx.viewpager.widget.ViewPager
        android:id="@+id/_vp"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        />
...

private List<Fragment> mFragment;
    private List<String> mTitle;
    private TabLayout mTabLayout;
    private ViewPager mViewPager;
    private void initFragment() {
        mTabLayout = (TabLayout)findViewById(R.id.playview_tab);
        mViewPager = (ViewPager)findViewById(R.id.playview_midd_vp);
        mFragment = new ArrayList<>();
        mFragment.add(new fragment_00());
        mFragment.add(new fragment_11());
        mFragment.add(new fragment_22());
        mFragment.add(new fragment_33());
        mTitle = new ArrayList<>();
        mTitle.add("歌曲");
        mTitle.add("歌词");
        mTitle.add("歌手");
        mTitle.add("专辑");
        XTab.addTab(mTabLayout,
                mViewPager,
                mFragment,
                mTitle,
                getSupportFragmentManager(),
                1,
                new XTab.onPageSelected() {
            @Override
            public void onPageSelected(int position) {

            }
        });
    }

com.xy.fragment I/fragment_00.java: [ (fragment_00.java:27)#onResume ] execute
com.xy.fragment I/fragment_11.java: [ (fragment_11.java:27)#onResume ] execute
com.xy.fragment I/fragment_22.java: [ (fragment_22.java:28)#onResume ] execute

com.xy.fragment I/fragment_00.java: [ (fragment_00.java:39)#onPause ] execute

/**
 * This method will be invoked when the current page is scrolled, either as part
 * of a programmatically initiated smooth scroll or a user initiated touch scroll.
 *
 * @param position 当前显示的第一页的位置索引。如果positionOffset不为零，则页面position + 1将可见。
 * @param positionOffset Value from [0, 1) 指示与位置上的页面的偏移量。
 * @param positionOffsetPixels Value 以像素为单位的值，指示与位置的偏移量。
 */
void onPageScrolled(int position, float positionOffset, @Px int positionOffsetPixels);

/**
 * Indicates that the pager is in an idle, settled state. The current page
 * is fully in view and no animation is in progress.
 * 空闲状态
 */
public static final int SCROLL_STATE_IDLE = 0;

/**
 * Indicates that the pager is currently being dragged by the user.
 * 滑动状态
 */
public static final int SCROLL_STATE_DRAGGING = 1;

/**
 * Indicates that the pager is in the process of settling to a final position.
 * 滑动完成，自动完成调整状态
 */
public static final int SCROLL_STATE_SETTLING = 2;

XTab.addTab(mTabLayout, 
                mViewPager,
                mFragment,
                mTitle, 
                getSupportFragmentManager(),
                2,
                new XTab.onPageSelected() {
            @Override
            public void onPageSelected(int position) {
                XToast.getInstance().Text("当前页面位置："+position).LayoutParamsY(750).show();
            }
        });