Hiding/Showing the toolbar when fragment in the tabs is scrolled

Question

I added the new Toolbar, Tablayout and Viewpager in my android app. I provided Fragments for my 3 Tabs and its working fine. But the problem is that when i scroll up my Toolbar does not hide. I want that when i scroll my fragment it should hide. And one more thing, i am using Webview in the fragment. My codes are given below.

MainActivity.Java

public class MainActivity extends AppCompatActivity {     TabLayout tabLayout; @Override protected void onCreate(Bundle savedInstanceState) {     super.onCreate(savedInstanceState);     setContentView(R.layout.main);          setupToolbar();         setupTablayout();     }  private void setupToolbar() {     // TODO Auto-generated method stub     Toolbar toolbar = (Toolbar) findViewById(R.id.toolbarsdfs);     if (toolbar != null) {         setSupportActionBar(toolbar);         getSupportActionBar().setDisplayHomeAsUpEnabled(true);} }  private void setupTablayout() {     // TODO Auto-generated method stub     tabLayout = (TabLayout) findViewById(R.id.tabLayout);     tabLayout.setTabGravity(TabLayout.GRAVITY_FILL);     tabLayout.addTab(tabLayout.newTab().setText("Tab 1"));     tabLayout.addTab(tabLayout.newTab().setText("Tab 2"));     final ViewPager viewPager = (ViewPager) findViewById(R.id.pager);     final PagerAdapter adapter = new PagerAdapter             (getSupportFragmentManager(), tabLayout.getTabCount());     viewPager.setAdapter(adapter);     viewPager.addOnPageChangeListener(new TabLayout.TabLayoutOnPageChangeListener(tabLayout));     tabLayout.setOnTabSelectedListener(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) {          }     }); } } 

main.xml

<android.support.design.widget.CoordinatorLayout     xmlns:android="http://schemas.android.com/apk/res/android"     xmlns:tools="http://schemas.android.com/tools"     xmlns:app="http://schemas.android.com/apk/res-auto"     android:id="@+id/coordinatorLayout"     android:layout_height="match_parent"     android:layout_width="match_parent">      <android.support.design.widget.AppBarLayout         android:id="@+id/appbar"         android:layout_width="match_parent"         android:layout_height="wrap_content"         android:theme="@style/ThemeOverlay.AppCompat.Dark.ActionBar">  <android.support.v7.widget.Toolbar     android:id="@+id/toolbarsdfs"     android:layout_width="match_parent"     android:layout_height="wrap_content"     android:minHeight="?attr/actionBarSize"     android:background="?attr/colorPrimaryDark"     android:theme="@style/ThemeOverlay.AppCompat.ActionBar"     app:layout_scrollFlags="scroll|enterAlways"/>  <android.support.design.widget.TabLayout             android:id="@+id/tabLayout"             android:scrollbars="horizontal"             android:layout_below="@+id/toolbar"             android:layout_width="match_parent"             android:layout_height="wrap_content"             android:background="?attr/colorPrimary" />  <android.support.v4.view.ViewPager         android:id="@+id/pager"         android:layout_width="match_parent"         android:layout_height="fill_parent"         android:layout_below="@+id/tablayout"/>  </android.support.design.widget.AppBarLayout> </android.support.design.widget.CoordinatorLayout> 

PagerAdapter.Java

public class PagerAdapter extends FragmentStatePagerAdapter {     int mNumOfTabs;      public PagerAdapter(FragmentManager fm, int NumOfTabs) {         super(fm);         this.mNumOfTabs = NumOfTabs;     }      @Override     public Fragment getItem(int position) {          switch (position) {             case 0:                 Fragment_Feeds tab1 = new Fragment_Feeds();                 return tab1;             case 1:                 Fragment_Facts tab2 = new Fragment_Facts();                 return tab2;             default:                 return null;         }     }      @Override     public int getCount() {         return mNumOfTabs;     } } 

Fragment_Feeds.java

public class Fragment_Feeds extends Fragment {     SwipeRefreshLayout swipeView;     WebView myWebView;     ProgressBar progressBar;     final static String myBlogAddr = "http://myblog.com";     String myUrl;     @Override     public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {         View view = inflater.inflate(R.layout.fragmentfeeds, container, false);         swipeView = (SwipeRefreshLayout) view.findViewById(R.id.swipe);          myWebView = (WebView) view.findViewById(R.id.webview);         progressBar = (ProgressBar) view.findViewById(R.id.progressBar);         myWebView.setWebViewClient(new MyWebViewClient());          WebSettings webSettings = myWebView.getSettings();         webSettings.setJavaScriptEnabled(true);         myWebView.setOverScrollMode(View.OVER_SCROLL_NEVER);         myWebView.setScrollBarStyle(WebView.SCROLLBARS_OUTSIDE_OVERLAY);         myWebView.setHorizontalScrollBarEnabled(false);         myWebView.loadUrl("http://myblog.com");         swipeView.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener()             {             @Override             public void onRefresh()              {                   myWebView.loadUrl("http://myblog.com");              }});         return view;     }     private class MyWebViewClient extends WebViewClient {         @Override         public void onPageFinished(WebView view, String url) {             swipeView.setRefreshing(false);         }         @Override         public boolean shouldOverrideUrlLoading(WebView view, String url) {          myUrl = url;             view.loadUrl(url);             return true;         }         @Override         public void onReceivedError(WebView view, int errorCod,String description, String failingUrl) {             myWebView.loadUrl("file:///android_asset/error_page.html");         }     }     @Override     public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {         inflater.inflate(R.menu.main, menu);         super.onCreateOptionsMenu(menu, inflater);     } } 

fragmentfeeds.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"     android:layout_width="match_parent"     android:layout_height="match_parent"     android:orientation="vertical"     android:background="#FFFFFF" >     <ProgressBar         android:id="@+id/progressBar"         style="?android:attr/progressBarStyleSmall"         android:layout_width="wrap_content"         android:layout_height="wrap_content" />      <android.support.v4.widget.SwipeRefreshLayout       xmlns:android="http://schemas.android.com/apk/res/android"       android:id="@+id/swipe"       android:layout_width="match_parent"       android:layout_height="match_parent"       android:background="#FFFFFF">s      <WebView       android:id="@+id/webview"       android:layout_width="match_parent"       android:layout_height="fill_parent"       android:numColumns="1"       android:scrollbars="none"       android:focusableInTouchMode="false"       android:focusable="false"       android:background="#FFFFFF" />    </android.support.v4.widget.SwipeRefreshLayout>  </LinearLayout> 

What i want?

What i want is that when i scroll the webview upwards, the toolbar should also scroll upwards and hides and when i scroll back down the toolbar should come back as soon as possible.