我尝试了很多解决方案，但他们没有工作..你能帮我解决..
我认为错误是由于getActivity（）中的null值，但我已经尝试了每个解决方案来删除它，可能是我错过了一些东西..
这就是事情
public class StuffMainFragment extends Fragment {
private ViewPager mPager;
private SlidingTabsLayout mTabs;
private OnFragmentInteractionListener mListener;
private LayoutInflater mMenuInflater;
public AppCompatActivity mCustomgetSupport;
public StuffMainFragment() {
// Required empty public constructor
}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View view=inflater.inflate(R.layout.fragment_stuff_main, container, false);
Toolbar toolbar = (Toolbar)view. findViewById(R.id.app_bar);
final ActionBar actionBar = ((AppCompatActivity) getActivity()).getSupportActionBar();
if (actionBar!=null) {
((AppCompatActivity)getActivity()).setSupportActionBar(toolbar);
actionBar.setDisplayShowHomeEnabled(true);
}
NavigationDrawerFragment drawerFragment=(NavigationDrawerFragment)
(getActivity()).getSupportFragmentManager().findFragmentById(R.id.nav_frag);
drawerFragment.setUp(R.id.nav_frag, (DrawerLayout)view.findViewById(R.id.drawer_layout),toolbar);
mPager=(ViewPager)view.findViewById(R.id.pager);
mPager.setAdapter(new MyPagerAdapter((getActivity()).getSupportFragmentManager()));
mTabs=(SlidingTabsLayout)view.findViewById(R.id.tabs);
mTabs.setDistributeEvenly(true);
mTabs.setBackgroundColor(getResources().getColor(R.color.colorPrimaryDark));
mTabs.setSelectedIndicatorColors(getResources().getColor(R.color.colorAccent));
mTabs.setViewPager(mPager);
return view;
}
public interface OnFragmentInteractionListener {
void onLogout();
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
switch (id) {
case R.id.action_logout:
Log.d("PK", "LOGOUT Menu Item Clicked!");
mListener.onLogout();
return true;
}
return false;
}
class MyPagerAdapter extends FragmentPagerAdapter {
String[] tabs;
public MyPagerAdapter(FragmentManager fm) {
super(fm);
tabs=getResources().getStringArray(R.array.tabs);
}
@Override
public Fragment getItem(int position) {
MyFragment myFrllagment=MyFragment.getInsance(position);
return myFrllagment;
}
@Override
public CharSequence getPageTitle(int position) {
return tabs[position];
}
@Override
public int getCount() {
return 6;
}
}
public static class MyFragment extends Fragment{
private TextView mTextView;
public static MyFragment getInsance(int position){
MyFragment myfragment=new MyFragment();
Bundle args=new Bundle();
args.putInt("position",position);
myfragment.setArguments(args);
return myfragment;
}
@Override
public View onCreateView(LayoutInflater inflater,@Nullable ViewGroup container,@Nullable Bundle savedInstanceState){
View layout=inflater.inflate(R.layout.fragment_my,container,false);
mTextView=(TextView)layout.findViewById(R.id.position);
Bundle bundle=getArguments();
if(bundle!=null)
{
mTextView.setText("The Page Selected Is"+bundle.getInt("position"));
}
return layout;
}
}
@Override
public void onAttach(Context context) {
super.onAttach(context);
if (context instanceof OnFragmentInteractionListener) {
mListener = (OnFragmentInteractionListener) context;
} else {
throw new RuntimeException(context.toString()
+ " must implement OnFragmentInteractionListener");
}
}
@Override
public void onActivityCreated(@Nullable Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
}
@Override
public void onDetach() {
super.onDetach();
mListener = null;
}
}
N错误是
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.rana.sahaj.myyu/com.rana.sahaj.myyu.MainActivity}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2200)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2249)
at android.app.ActivityThread.access$800(ActivityThread.java:141)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1212)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5052)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:609)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at com.rana.sahaj.myyu.StuffMainFragment.onCreateView(StuffMainFragment.java:69)
at android.support.v4.app.Fragment.performCreateView(Fragment.java:1962)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1067)
at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1248)
at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:738)
at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1613)
at android.support.v4.app.FragmentController.execPendingActions(FragmentController.java:330)
at android.support.v4.app.FragmentActivity.onStart(FragmentActivity.java:547)
at android.app.Instrumentation.callActivityOnStart(Instrumentation.java:1171)
at android.app.Activity.performStart(Activity.java:5258)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2173)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2249)
at android.app.ActivityThread.access$800(ActivityThread.java:141)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1212)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5052)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:515)
fragment_stuff_main.xml
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/stuffID"
tools:context="com.rana.sahaj.myyu.StuffMainFragment">
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
xmlns:app="http://schemas.android.com/apk/res-auto"
tools:context="com.rana.sahaj.myyu.MainActivity">
<android.support.v4.widget.DrawerLayout android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/drawer_layout"
xmlns:app="http://schemas.android.com/apk/res-auto"
tools:context="com.rana.sahaj.myyu.MainActivity">
<LinearLayout
android:layout_below="@+id/app_bar"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#263238"
android:orientation="vertical">
<include layout="@layout/app_bar"
android:id="@+id/app_bar"/>
<com.rana.sahaj.myyu.tabs.SlidingTabsLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="@+id/tabs"
app:tabGravity="fill"
app:tabMode="scrollable"
app:tabSelectedTextColor="@color/colorAccent"
app:theme="@style/MyCustomThemeToolbar"/>
<android.support.v4.view.ViewPager
android:id="@+id/pager"
android:layout_width="match_parent"
android:layout_height="0dp"
android:layout_weight="1"/>
</LinearLayout>
<RelativeLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:gravity="bottom|end"
android:layout_margin="@dimen/fab_margin">
</RelativeLayout>
<fragment
android:id="@+id/nav_frag"
android:layout_width="@dimen/nav_drawer_width"
android:layout_height="match_parent"
android:name="com.rana.sahaj.myyu.NavigationDrawerFragment"
android:layout_gravity="start"
app:layout="@layout/fragment_navigation_drawer"
tools:layout="@layout/fragment_navigation_drawer"/>
</android.support.v4.widget.DrawerLayout>
</android.support.v4.widget.DrawerLayout>
强文
包含的tablayout（我已经包含在内）..
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.Toolbar xmlns:android="http://schemas.android.com/apk/res/android"
android:paddingTop="@dimen/app_bar_top_padding"
android:layout_width="match_parent"
android:layout_height="wrap_content" xmlns:app="http://schemas.android.com/apk/res-auto"
android:background="#1A237E"
app:theme="@style/MyCustomThemeToolbar"
app:popupTheme="@style/MyCustomOverlay" >
</android.support.v7.widget.Toolbar>