这是 Bug 了吗？

https://zippy.gfycat.com/GratefulKeyChamois.webm

情况如上， PagerTabStrip 的 title 刚打开程序不显示，必须要拉动到下一个界面才会出现。

在网上找了个遍，都没发现原因，代码也是最基本的初始化，没做任何自定义，感觉要么是 Bug 、要么是手机问题。

这是代码：

MainActivity.java

package com.example.system.myapplication; import android.app.Activity; import android.os.Bundle; import android.support.annotation.Nullable; import android.support.v4.view.ViewPager; import android.view.View; import java.util.ArrayList; import java.util.List; public class MainActivity extends Activity { @Override protected void onCreate(@Nullable Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main_activity); List<View> viewList = new ArrayList<>(); View view1 = View.inflate(this, R.layout.view1, null); View view2 = View.inflate(this, R.layout.view2, null); View view3 = View.inflate(this, R.layout.view3, null); View view4 = View.inflate(this, R.layout.view4, null); viewList.add(view1); viewList.add(view2); viewList.add(view3); viewList.add(view4); List<String> titleList = new ArrayList<>(); titleList.add("第一个页面"); titleList.add("第二个页面"); titleList.add("第三个页面"); titleList.add("第四个页面"); MyPagerAdapter myPagerAdapter = new MyPagerAdapter(viewList, titleList); ViewPager viewPager = (ViewPager) findViewById(R.id.viewPager); viewPager.setAdapter(myPagerAdapter); } } 

PagerAdapter 适配器

package com.example.system.myapplication; import android.support.v4.view.PagerAdapter; import android.view.View; import android.view.ViewGroup; import java.util.List; public class MyPagerAdapter extends PagerAdapter { private List<View> viewList; private List<String> titleList; public MyPagerAdapter(List<View> viewList, List<String> titleList) { this.viewList = viewList; this.titleList = titleList; } @Override public int getCount() { return viewList.size(); } @Override public boolean isViewFromObject(View view, Object object) { return view == object; } @Override public Object instantiateItem(ViewGroup container, int position) { View view = viewList.get(position); container.addView(view); return view; } @Override public void destroyItem(ViewGroup container, int position, Object object) { View view = viewList.get(position); container.removeView(view); } @Override public CharSequence getPageTitle(int position) { return titleList.get(position); } } 

main_activity.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:layout_width="match_parent" android:layout_height="match_parent"> <android.support.v4.view.ViewPager android:id="@+id/viewPager" android:layout_gravity="center" android:layout_width="wrap_content" android:layout_height="wrap_content"> <android.support.v4.view.PagerTabStrip android:id="@+id/tab" android:layout_gravity="top" android:layout_width="wrap_content" android:layout_height="wrap_content"> </android.support.v4.view.PagerTabStrip> </android.support.v4.view.ViewPager> </LinearLayout>