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Question

我在这里搜索过但没有找到我的解决方案。所以我发布了我的问题，当我们点击选项卡时它的工作正常但是当我们滚动viewPager时它并没有完美地工作。动态高度有一些问题。一些内容没有显示。

我的Xml是

 <my_packagename.ViewPager_Height
            android:id="@+id/pager"
            android:layout_width="match_parent"
            android:nestedScrollingEnabled="false"
            android:layout_height="wrap_content" />

现在我的java文件就像

public class ViewPager_Height extends ViewPager {

private View mCurrentView;

public ViewPager_Height(Context context) {
    super(context);
}

public ViewPager_Height(Context context, AttributeSet attrs) {
    super(context, attrs);
}

@Override
public void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
    if (mCurrentView == null) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        return;
    }
    int height = 0;
    mCurrentView.measure(widthMeasureSpec, MeasureSpec.makeMeasureSpec(0, MeasureSpec.UNSPECIFIED));
    int h = mCurrentView.getMeasuredHeight();
    if (h > height) height = h;
    heightMeasureSpec = MeasureSpec.makeMeasureSpec(height, MeasureSpec.EXACTLY);

    super.onMeasure(widthMeasureSpec, heightMeasureSpec);
}

public void measureCurrentView(View currentView) {
    mCurrentView = currentView;
    requestLayout();
}

public int measureFragment(View view) {
    if (view == null)
        return 0;

    view.measure(0, 0);
    return view.getMeasuredHeight();
}

}

和主要类是

 final ViewPager_Height viewPager = (ViewPager_Height) findViewById(R.id.pager);
        TabLayout tabLayout = (TabLayout) findViewById(R.id.tab_layout);

        tabLayout.addTab(tabLayout.newTab().setText(about_us));
        tabLayout.addTab(tabLayout.newTab().setText(listing));
        tabLayout.addTab(tabLayout.newTab().setText(contact));

        DynamicheightTabsAdapter adapter;
        adapter = new DynamicheightTabsAdapter(getSupportFragmentManager(), "TASK");
        viewPager.setAdapter(adapter);
        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) {

            }
        });


    }
}

最后我的Adapter类就像

public class DynamicheightTabsAdapter extends FragmentPagerAdapter {

private List<Fragment> fragments;
private int mCurrentPosition = -1;

public DynamicheightTabsAdapter(FragmentManager fm, String takidetifier) {
    super(fm);
    this.fragments = new ArrayList<>();

    switch (takidetifier){
        case "Task":
            fragments.add(new MyFirstFragment());
            fragments.add(new  MySecondFragment());
            fragments.add(new  MyThirdFragment());
            break;


    }



}

@Override
public void setPrimaryItem(ViewGroup container, int position, Object object) {
    super.setPrimaryItem(container, position, object);
    if (position != mCurrentPosition) {
        Fragment fragment = (Fragment) object;
        ViewPager_Height pager = (ViewPager_Height) container;
        if (fragment != null && fragment.getView() != null) {
            mCurrentPosition = position;
            pager.measureCurrentView(fragment.getView());
        }
    }
}

@Override
public Fragment getItem(int position) {
    return fragments.get(position);
}

@Override
public int getCount() {
    return fragments.size();
}

}

Answer 1

在OnTabSelected中调用adapter.notifyDataSetChanged（） 所以新代码将是，

public void onTabSelected(TabLayout.Tab tab) { viewPager.setCurrentItem(tab.getPosition()); adapter.notifyDataSetChanged() }