Collapsing toolbar with map fragment inside and view pager

activity_model_information.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.design.widget.CoordinatorLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/information_coordinator_layout"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:fitsSystemWindows="true">

    <android.support.design.widget.AppBarLayout
        android:id="@+id/appbar"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:theme="@style/AppTheme.AppBarOverlay">

        <android.support.design.widget.CollapsingToolbarLayout
            android:id="@+id/collapsingToolbarLayout"
            android:layout_width="match_parent"
            android:layout_height="280dp"
            app:contentScrim="?attr/colorPrimary"
            app:expandedTitleMarginStart="48dp"
            app:expandedTitleMarginEnd="64dp"
            app:layout_scrollFlags="scroll|snap">

            <FrameLayout
                android:id="@+id/mapContainer"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                app:layout_collapseMode="parallax"/>

        </android.support.design.widget.CollapsingToolbarLayout>

        <android.support.v7.widget.Toolbar
            android:id="@+id/toolbar"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:minHeight="56dp"
            android:background="?colorPrimary"
            android:layout_marginTop="-56dp"
            app:popupTheme="@style/AppTheme.PopupOverlay"
            app:layout_scrollFlags="scroll|enterAlways|snap" />

        <include
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_marginTop="-112dp"
            layout="@layout/activity_model_information_header" />

        <android.support.design.widget.TabLayout
            android:id="@+id/sliding_tabs"
            android:layout_width="match_parent"
            android:layout_height="?attr/actionBarSize"
            app:tabIndicatorHeight="4dp"
            app:tabMode="fixed" />

    </android.support.design.widget.AppBarLayout>

    <DeactivatableViewPager
        android:id="@+id/viewpager"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:background="@android:color/white"
        app:layout_behavior="@string/appbar_scrolling_view_behavior"/>

</android.support.design.widget.CoordinatorLayout>

activity_model_information_header.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    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="wrap_content"
    android:orientation="vertical"
    android:gravity="center"
    app:layout_scrollFlags="scroll|enterAlways|snap">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="112dp"
        android:padding="6dp"
        android:gravity="center">

        <TextView
            android:id="@+id/circleView"
            android:layout_width="100dp"
            android:layout_height="100dp"
            android:text="@string/name"
            android:background="@drawable/background_circle"
            android:textSize="18sp"
            android:gravity="center"
            android:textStyle="bold"
            android:textColor="@color/white"/>

    </LinearLayout>

    <TextView
        android:id="@+id/nameTextView"
        android:layout_width="match_parent"
        android:layout_height="28dp"
        android:gravity="center"
        android:text="@string/name"
        android:textAppearance="@style/TextAppearance.AppCompat.Widget.ActionBar.Title" />

    <TextView
        android:id="@+id/descriptionTextView"
        android:gravity="center"
        android:layout_width="match_parent"
        android:layout_height="28dp"
        android:text="@string/unique_identifier"
        android:textAppearance="@style/TextAppearance.AppCompat.Widget.ActionBar.Subtitle" />

</LinearLayout>

ActivityHelper.java

/**
 * Helper class which provides methods to being, redirect, start and finish activities.
 */
public class ActivityHelper {

    /**
     * The {@code fragment} is added to the container view with id {@code frameId}. The operation is
     * performed by the {@code fragmentManager}.
     *
     */
    public static void addFragmentToActivity(
            @NonNull FragmentManager fragmentManager,
            @NonNull Fragment fragment,
            int frameId
    ) {
        checkNotNull(fragmentManager);
        checkNotNull(fragment);
        FragmentTransaction transaction = fragmentManager.beginTransaction();
        transaction.add(frameId, fragment);
        transaction.commit();
    }

}

ActivityModelInformation.java

public class ActivityModelInformation extends InformationActivity {
  
    private HeaderViewHolder headerInformationHolder;

    private TabLayout tabLayout;
    private DeactivatableViewPager viewPager;
    private MapViewFragment mapFragment;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_model_information);
        super.baseSetup();
        setupViewPager();
        setupMapFragment();
    }

    @Override
    protected void onResume() {
        super.onResume();
        //CALL PRESENTER TO FETCH DATA
    }

    @Override
    protected void initViews() {
        super.initViews();
        viewPager = (DeactivatableViewPager) findViewById(R.id.viewpager);
        tabLayout = (TabLayout) findViewById(R.id.sliding_tabs);
        headerInformationHolder = new HeaderViewHolder(findViewById(android.R.id.content));
        //INITIALIZE PRESENTER.
      
    }
  
    @Override
    protected void setInformationData() {
        Bundle bundle = getIntent().getExtras();
        //SET CLASS VARIABLES from BUNDLE
        updateUIHeader();
    }

    /**
     * This method is NOT used by this class.
     * @param isCollapsed state of toolbar.
     */
    @Override
    protected void onToolbarCollapsed(boolean isCollapsed) {
        //IMPORTANT! Do nothing
    }

    /**
     * Retrieves a custom activity title for display on toolbar.
     * @return activity title.
     */
    @Override
    public String getActivityTitle() {
        return "Custom Activity Title";
    }

    /**
     * Updates the flowmeter header information.
     */
    private void updateUIHeader(){
        //UPDATE VALUES ON HEADER VIEW HOLDER
    }


    /**
     * Setup the view pager that shows information about the parameters.
     */
    private void setupViewPager() {
        //INITIALIZE THE ADAPTER
        viewPager.addOnPageChangeListener(new ViewPager.OnPageChangeListener() {
            public void onPageScrollStateChanged(int state) {}
            public void onPageScrolled(int position, float positionOffset, int positionOffsetPixels) {}

            public void onPageSelected(int position) {
                boolean pagingEnable = true;
                /*if(position == MyAdapter.PAGE_NEED_IT_TO_MATCH){
                    pagingEnable = false;
                }*/
                viewPager.setPagingEnabled(pagingEnable);
            }
        });
        viewPager.setAdapter(sectionsPagerAdapter);
        tabLayout.setupWithViewPager(viewPager);
    }

    /**
     * This method setups a {@link MapViewFragment} to show the flowmeter location.
     * This method also validates if Google Play Services are available on the current device.
     * If there is no Google Play Services API available the map is not displayed on UI.
     */
    private void setupFlowmeterMapFragment() {
        final int status = GoogleApiAvailability.getInstance().isGooglePlayServicesAvailable(this);
        if (status != ConnectionResult.SUCCESS) {
            FrameLayout mapContainer = (FrameLayout) findViewById(R.id.mapContainer);
            mapContainer.setVisibility(View.GONE);
        } else {
            mapFragment = (MapViewFragment) getSupportFragmentManager()
                    .findFragmentById(R.id.mapContainer);

            if (mapFragment == null) {
                mapFragment = MapViewFragment.newInstance(/* Parameters if you need */);
                ActivityHelper.addFragmentToActivity(
                        getSupportFragmentManager(), mapFragment, R.id.mapContainer);
            }
        }
    }
}

background_circle.xml

<?xml version="1.0" encoding="utf-8"?>
<shape
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="oval">

    <solid android:color="@color/white" />

    <size
        android:height="100dp"
        android:width="100dp"/>

    <padding
        android:bottom="15dp"
        android:top="15dp"
        android:left="15dp"
        android:right="15dp"/>
</shape>

DeactivatableViewPager.java

/**
 * Allows to deactivate the paging on a {@link ViewPager} component.
 */
public class DeactivatableViewPager extends ViewPager {

    private boolean isPagingEnabled = true;

    public DeactivatableViewPager(Context context) {
        super(context);
    }

    public DeactivatableViewPager(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    public boolean onTouchEvent(MotionEvent event) {
        return this.isPagingEnabled && super.onTouchEvent(event);
    }

    @Override
    public boolean onInterceptTouchEvent(MotionEvent event) {
        return this.isPagingEnabled && super.onInterceptTouchEvent(event);
    }

    public void setPagingEnabled(boolean b) {
        this.isPagingEnabled = b;
    }
}

fragment_model_location.xml

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:map="http://schemas.android.com/tools"
    android:id="@+id/supportMapContainer"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <FrameLayout
        android:id="@+id/map"
        android:name="com.google.android.gms.maps.SupportMapFragment"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        map:cameraZoom="13"
        map:mapType="normal"
        map:liteMode="true" />

    <LinearLayout
        android:id="@+id/mapButtons"
        android:orientation="horizontal"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_alignParentTop="true"
        android:layout_alignParentRight="true"
        android:layout_alignParentEnd="true"
        android:layout_marginRight="15dip"
        android:layout_marginEnd="15dip"
        android:layout_marginTop="15dip">

        <ImageButton
            android:id="@+id/location"
            android:src="@drawable/ic_crosshair_gps"
            style="@style/MapControlButton"/>

        <ImageButton
            android:id="@+id/zoom_in"
            android:layout_marginLeft="5dip"
            android:layout_marginStart="5dip"
            android:src="@drawable/ic_plus"
            style="@style/MapControlButton"/>

        <ImageButton
            android:id="@+id/zoom_out"
            android:src="@drawable/ic_minus"
            android:layout_marginLeft="5dip"
            android:layout_marginStart="5dip"
            style="@style/MapControlButton"/>

    </LinearLayout>

</RelativeLayout>

HeaderViewHolder.java

/**
 * Created by luisburgos on 8/18/16.
 */
public class HeaderViewHolder extends RecyclerView.ViewHolder {

    public View cirlceView;
    public TextView nameTextView;
    public TextView descriptionTextView;

    public HeaderViewHolder(View itemView) {
        super(itemView);
        cirlceView = itemView.findViewById(R.id.cirlceView);
        nameTextView = (TextView) itemView.findViewById(R.id.nameTextView);
        descriptionTextView = (TextView) itemView.findViewById(R.id.descriptionTextView);
    }

}

InformationActivity.java

/**
 * Base UI View to show a basic information about a domain model.
 * This class has basic components like {@link CoordinatorLayout} and
 * {@link AppBarLayout}.
 * Created by luisburgos on 8/31/16.
 */
public abstract class InformationActivity extends AppCompatActivity {

    protected CoordinatorLayout coordinatorLayout;
    protected AppBarLayout appBarLayout;
    protected CollapsingToolbarLayout collapsingToolbarLayout;
    protected Toolbar toolbar;

    /**
     * This method has sequential cohesion in order to achieve a
     * correct configuration for the activity. This method NEEDS to be called from
     * concrete implementations.
     *
     * This method depends on {@link InformationActivity#initViews()},
     * {@link InformationActivity#setInformationData()}, {@link InformationActivity#setupToolbar()},
     * {@link InformationActivity#setupAppBar()}
     */
    protected void baseSetup(){
        this.initViews();
        this.setInformationData();
        this.setupToolbar();
        this.setupAppBar();
    }

    /**
     * BINDS xml components to class variables.
     */
    protected void initViews() {
        coordinatorLayout = (CoordinatorLayout) findViewById(R.id.information_coordinator_layout);
        collapsingToolbarLayout = (CollapsingToolbarLayout) findViewById(R.id.collapsingToolbarLayout);
        toolbar = (Toolbar) findViewById(R.id.toolbar);
        appBarLayout = (AppBarLayout) findViewById(R.id.appbar);
    }

    /**
     * Displays home back button and enables back pressed behavior.
     */
    protected void setupToolbar() {
        setSupportActionBar(toolbar);
        if(getSupportActionBar() != null){
            getSupportActionBar().setDisplayHomeAsUpEnabled(true);
            getSupportActionBar().setDisplayShowTitleEnabled(false);
        }
        toolbar.setNavigationOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                onBackPressed();
            }
        });
    }

    /**
     * Sets a {@link AppBarLayout.OnOffsetChangedListener} to the AppBar and notifies when
     * offset change and is less than 25.
     */
    protected void setupAppBar() {
        appBarLayout.addOnOffsetChangedListener(new AppBarLayout.OnOffsetChangedListener() {

            boolean isShow = false;
            int scrollRange = -1;

            @Override
            public void onOffsetChanged(AppBarLayout appBarLayout, int verticalOffset) {
                if (scrollRange == -1) {
                    scrollRange = appBarLayout.getTotalScrollRange();
                }
                if (scrollRange + verticalOffset <= 25) {
                    onToolbarCollapsed(true);
                    isShow = true;
                } else if(isShow) {
                    onToolbarCollapsed(false);
                    isShow = false;
                }
            }
        });
    }

    /**
     * Shows a {@link Snackbar} with the message to show.
     * @param message text to show.
     */
    protected void showMessage(String message) {
        if(coordinatorLayout == null){
            return;
        }
        Snackbar.make(coordinatorLayout, message, Snackbar.LENGTH_LONG).show();
    }

    /**
     * This method is NOT used by this class.
     * @param isCollapsed state of toolbar.
     */
    protected abstract void onToolbarCollapsed(boolean isCollapsed);

    /**
     * Retrieves a custom activity title for display on toolbar.
     * @return activity title.
     */
    protected abstract String getActivityTitle();

    /**
     * This method is needed to retrieve information a set the current activity information.
     * It could be necessary to implement a extra method to update the UI.
     */
    protected abstract void setInformationData();
}

MapViewFragment.java

import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageButton;

import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.CameraPosition;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;

/**
 *
 */
public class MapViewFragment extends Fragment implements OnMapReadyCallback {

    private SupportMapFragment mapFragment;
    private GoogleMap mMap = null;
    private Marker mMarker;

    private LatLng initialPoint;

    public MapViewFragment(){
        //REQUIRES EMPTY CONSTRUCTOR
    }

    public static MapViewFragment newInstance( /* Add parameters if you need */ ){
        Bundle arguments = new Bundle();
        /*arguments.putSerializable(KEY, value);*/
        MapViewFragment fragment = new MapViewFragment();
        fragment.setArguments(arguments);
        return fragment;
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View root = inflater.inflate(R.layout.fragment_model_location, container, false);
        setupMapControlButtons(root);
        return root;
    }

    @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        //GET VALUES FROM ARGUMENTS.
        /*valueVariable = (String) getArguments().getSerializable(KEY);*/
    }

    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
        FragmentManager fm = getChildFragmentManager();
        mapFragment = (SupportMapFragment) getActivity().getSupportFragmentManager().findFragmentById(R.id.map);
        if (mapFragment == null) {
            mapFragment = SupportMapFragment.newInstance();
            fm.beginTransaction().replace(R.id.map, mapFragment).commit();
        }
    }

    @Override
    public void onResume() {
        super.onResume();
        mapFragment.getMapAsync(this);
    }

    @Override
    public void onMapReady(GoogleMap googleMap) {
        this.mMap = googleMap;
        initialPoint = /* IMPORTANT!! FIND A WAY TO PARSE A LAT LNG POSITION*/

        if(initialPoint != null){
            setupMarker(initialPoint);
            setupMarkerInfoAction();
        }
    }

    private void setupMarkerInfoAction() {
        mMap.setOnInfoWindowClickListener(new GoogleMap.OnInfoWindowClickListener() {
            @Override
            public void onInfoWindowClick(Marker marker) {
                displayOpenOnGoogleMapsDialog();
            }
        });
    }

    private void displayOpenOnGoogleMapsDialog() {
       //IMPORTANT! Display a Dialog to Open on Google Maps.
    }

    private void zoomToCurrentLatLngPosition(LatLng initialPoint) {
        CameraPosition cameraPosition = new CameraPosition.Builder()
                .target(initialPoint)
                .zoom(9)
                .build();

        mMap.animateCamera(CameraUpdateFactory.newCameraPosition(cameraPosition));
    }

    private void setupMarker(@NonNull LatLng initialPoint) {
        this.mMarker = this.mMap.addMarker(
                new MarkerOptions()
                        .position(initialPoint)
                        .title(yourCustomTitleHere)
                        .icon(BitmapDescriptorFactory.fromResource(R.drawable.ic_custom_marker_of_your_choice))
        );
        mMarker.showInfoWindow();
        zoomToCurrentLatLngPosition(initialPoint);
    }

    private void setupMapControlButtons(View root) {
        final ImageButton locationButton = (ImageButton) root.findViewById(R.id.location);
        final ImageButton zoomInButton = (ImageButton) root.findViewById(R.id.zoom_in);
        final ImageButton zoomOutButton = (ImageButton) root.findViewById(R.id.zoom_out);
        locationButton.setVisibility(View.VISIBLE);
        zoomInButton.setVisibility(View.VISIBLE);
        zoomOutButton.setVisibility(View.VISIBLE);
        locationButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                if(initialPoint != null){
                    zoomToCurrentLatLngPosition(initialPoint);
                }
            }
        });
        zoomInButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                mMap.animateCamera(CameraUpdateFactory.zoomIn());
            }
        });
        zoomOutButton.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                mMap.animateCamera(CameraUpdateFactory.zoomOut());
            }
        });
    }

}

styles.mxl

<resources>

    <style name="MapControlButton">
        <item name="android:layout_width">25dip</item>
        <item name="android:layout_height">25dip</item>
        <item name="android:visibility">gone</item>
        <item name="android:background">@drawable/background_dodgerblue_rounded_corners</item>
    </style>

</resources>