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我正在抽屜應用程序與片段。抽屜中的一個選項調用了一個片段，我在其中設置了一個顯示圖形的選項卡式視圖（帶有片段）。Android ViewPager在第一次後不顯示內容
當我第一次運行應用程序時，我的標籤工作得很好，內容，圖形和一切看起來都很棒。
只要我點擊該片段並轉到任何其他片段並返回，標籤就會顯示正確的標題，但不會顯示任何內容，也不會顯示任何圖片。
這裏是樹立viewpager我的主要片段：
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
import android.support.v4.view.ViewPager;
public class StatsMain extends Fragment {
private ViewPagerAdapter adapter = null;
private TabLayout tabLayout = null;
private ViewPager viewPager = null;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.stats_main, container, false);
}
@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
viewPager = (ViewPager) view.findViewById(R.id.viewpager);
tabLayout = (TabLayout) view.findViewById(R.id.tabs);
setupViewPager(viewPager);
tabLayout.setupWithViewPager(viewPager);
}
private void setupViewPager(ViewPager viewPager) {
adapter = new ViewPagerAdapter(getFragmentManager());
adapter.addFragment(new Stats1(), "Stats 1");
adapter.addFragment(new Stats2(), "Stats 2");
viewPager.setAdapter(adapter);
}
class ViewPagerAdapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public ViewPagerAdapter(FragmentManager manager) {
super(manager);
}
@Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
@Override
public int getCount() {
return mFragmentList.size();
}
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
@Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
}
}
這裏是我爲它的佈局：
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:layout_width="match_parent"
android:layout_height="match_parent">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">
<android.support.design.widget.TabLayout
android:id="@+id/tabs"
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:tabMode="fixed"
app:tabGravity="fill"/>
</android.support.design.widget.AppBarLayout>
<android.support.v4.view.ViewPager
android:id="@+id/viewpager"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="@string/appbar_scrolling_view_behavior" />
</android.support.design.widget.CoordinatorLayout>
這是我的統計（數據）片段中的一個。第二個看起來非常相似：
public class Stats1 extends Fragment {
GraphView graph;
public Stats1() {
// Required empty public constructor
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
return inflater.inflate(R.layout.stats1, container, false);
}
@Override
public void onViewCreated(View view, Bundle savedInstanceState){
Calendar calendar = Calendar.getInstance();
Date d1 = calendar.getTime();
calendar.add(Calendar.DATE, 1);
Date d2 = calendar.getTime();
calendar.add(Calendar.DATE, 1);
Date d3 = calendar.getTime();
calendar.add(Calendar.DATE, 1);
Date d4 = calendar.getTime();
calendar.add(Calendar.DATE, 1);
Date d5 = calendar.getTime();
graph = (GraphView) view.findViewById(R.id.graph);
StaticLabelsFormatter staticLabelsFormatter = new
StaticLabelsFormatter(graph);
staticLabelsFormatter.setHorizontalLabels(new String[] {"old", "middle", "new"});
graph.setTitle("Data History");
LineGraphSeries<DataPoint> series = new LineGraphSeries<DataPoint>(new DataPoint[] {
new DataPoint(d1, 145.4),
new DataPoint(d2, 145.9),
new DataPoint(d3, 147.2),
new DataPoint(d4, 146.5),
new DataPoint(d5, 147.1)
});
graph.getViewport().setScalable(true);
graph.addSeries(series);
// set date label formatter
//graph.getGridLabelRenderer().setLabelFormatter(new
DateAsXAxisLabelFormatter(this));
graph.getGridLabelRenderer().setLabelFormatter(staticLabelsFormatter);
//graph.getGridLabelRenderer().setNumHorizontalLabels(6); // only 4 because of the space
series.setDrawDataPoints(true);
// set manual x bounds to have nice steps
graph.getViewport().setMinX(d1.getTime());
graph.getViewport().setMaxX(d5.getTime());
graph.getViewport().setXAxisBoundsManual(true);
// as we use dates as labels, the human rounding to nice readable numbers
// is not necessary
graph.getGridLabelRenderer().setHumanRounding(false);
}
我使用appsthatmatter/GraphView進行繪圖。
我試圖調試它，我發現後，我從導航的標籤離開和回來，功能：
@Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
將不會再被調用。它第一次做了兩次，但它永遠不會，直到我正確關閉應用程序並重新啓動。
有人可以幫我弄清楚我做得不對嗎？
謝謝