【发布时间】：2018-08-20 19:39:39
【问题描述】：
我有 3 个标签，每个标签共享一个片段。但是这个片段包含一个viewPager。所以所有三个选项卡都会有一个带有 viewPager 的 UI，而 viewPager 有三个不同的片段。在遵循可用示例之后，我设法用单个片段实现了 Tab 布局。但是当我尝试在这个片段中实现 viewPager 时，我遇到了问题。选项卡滚动不顺畅，也没有移动到第三个选项卡。我也看不到我的 viewPager 片段。
带有tablayout实现的主要片段：
public class DashboardFragment extends android.support.v4.app.Fragment {
Activity mActivity;
private TabLayout tabLayout;
private ViewPager viewPager;
private static final String TAG = "DashboardFragment";
public DashboardFragment() {
}
@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mActivity = getActivity();
}
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.dashboard_fragment, container, false);
tabLayout = (TabLayout)view.findViewById(R.id.tabs);
viewPager = (ViewPager)view.findViewById(R.id.viewpager);
tabLayout.addTab(tabLayout.newTab().setText("Yesterday"));
tabLayout.addTab(tabLayout.newTab().setText("Last Week"));
tabLayout.addTab(tabLayout.newTab().setText("This Month"));
setupViewPager(viewPager);
return view;
}
private void setupViewPager(ViewPager viewPager) {
DashboardTabPagerAdapter adapter = new DashboardTabPagerAdapter(((AppCompatActivity)getActivity()).getSupportFragmentManager(),tabLayout.getTabCount());
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) {
}
});
}
}
DashboardPagerAdapter：
public class DashboardTabPagerAdapter extends FragmentStatePagerAdapter {
private int mNoOfTabs;
public DashboardTabPagerAdapter(FragmentManager fm, int tabCount) {
super(fm);
mNoOfTabs=tabCount;
}
@Override
public Fragment getItem(int position) {
DashboardYesterdayFragment fragment = new DashboardYesterdayFragment();
Bundle args = new Bundle();
switch (position) {
case 0:
args.putSerializable(AppConstants.TAB_DASHBOARD_TYPE, AppConstants.TAB_DASHBOARD_YESTERDAY);
break;
case 1:
args.putSerializable(AppConstants.TAB_DASHBOARD_TYPE, AppConstants.TAB_DASHBOARD_LAST_WEEK);
break;
case 2:
args.putSerializable(AppConstants.TAB_DASHBOARD_TYPE, AppConstants.TAB_DASHBOARD_THIS_MONTH);
break;
default:
return null;
}
fragment.setArguments(args);
return fragment;
}
@Override
public int getCount() {
return mNoOfTabs;
}
}
包含 childViewPager 的 TabFragment：
public class DashboardYesterdayFragment extends android.support.v4.app.Fragment {
private String title;
private Bundle bundle;
ViewPager mViewPager;
public DashboardYesterdayFragment(){
}
@Override
public void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
bundle = getArguments();
}
}
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.dashboard_yesterday_layout, container, false);
mViewPager = view.findViewById(R.id.vpPager);
setupViewPager(mViewPager);
return view;
}
private void setupViewPager(ViewPager viewPager) {
DashboardViewPagerAdapter adapter = new DashboardViewPagerAdapter( getChildFragmentManager(),bundle);
mViewPager.setAdapter(adapter);
mViewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
@Override
public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {
}
@Override
public void onPageSelected(int position) {
}
@Override
public void onPageScrollStateChanged(int state) {
}
});
mViewPager.setPageMargin(24);
}
ChildViewPagerAdapter：
public class DashboardViewPagerAdapter extends FragmentStatePagerAdapter {
private static int NUM_ITEMS = 3;
private Bundle bundle;
public DashboardViewPagerAdapter(FragmentManager fm, Bundle bundle) {
super(fm);
this.bundle=bundle;
}
@Override
public Fragment getItem(int position) {
switch (position) {
case 0:
return IncidentsFragment.newInstance(bundle);
case 1:
return VehicleUtilizationFragment.newInstance(bundle);
case 2:
return FleetPerformanceFragment.newInstance(bundle);
default:
return null;
}
}
@Override
public int getCount() {
return NUM_ITEMS;
}
}
ChildViewPager 第一个片段：
public class IncidentsFragment extends Fragment {
private TextView mOverSpeeding,mGeoFence,mIdlingCase,mFuelFilling,mMosetIncidences, mLeastIncidences;
public static IncidentsFragment newInstance(Bundle bundle) {
IncidentsFragment fragmentFirst = new IncidentsFragment();
Bundle args = new Bundle();
args.putBundle("bundle", bundle);
fragmentFirst.setArguments(args);
return fragmentFirst;
}
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.incident_layout, container, false);
initViews(view);
return super.onCreateView(inflater, container, savedInstanceState);
}
private void initViews(View view) {
mOverSpeeding = (TextView)view.findViewById(R.id.over_speeding_value);
mGeoFence = (TextView)view.findViewById(R.id.geofence_value);
mIdlingCase = (TextView)view.findViewById(R.id.idling_value);
mFuelFilling = (TextView)view.findViewById(R.id.fuel_value);
mMosetIncidences = (TextView)view.findViewById(R.id.vehicle_reg_no);
mLeastIncidences = (TextView)view.findViewById(R.id.least_incidences_value);
}
}
我很困惑出了什么问题。
【问题讨论】：
标签： android android-fragments android-viewpager