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Navigation Drawer not responding when I click on it

Once I click the Navigation Drawer on my app nothing is happening. I tried so many fixes but nothing is working for me. I created a new project with the same main java code and it worked fine. not sure where I went wrong.
home_fragment.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#90EE90"
tools:context=".ui.home.HomeFrag">
<TextView
android:id="#+id/homefrag_date"
android:layout_width="207dp"
android:layout_height="23dp"
android:layout_marginStart="117dp"
android:layout_marginTop="69dp"
android:layout_marginEnd="87dp"
android:layout_marginBottom="639dp"
android:text="#string/Date"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<androidx.constraintlayout.widget.Guideline
android:id="#+id/guideline2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_begin="20dp" />
<androidx.constraintlayout.widget.Guideline
android:id="#+id/guideline3"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="horizontal"
app:layout_constraintGuide_begin="20dp" />
<TextClock
android:id="#+id/hamza_time"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="117dp"
android:layout_marginTop="123dp"
android:layout_marginBottom="589dp"
android:format12Hour="hh:mm:ss a"
android:text="#string/Current_Time"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<TextView
android:id="#+id/hamza_displaydate"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="27dp"
android:layout_marginTop="73dp"
android:layout_marginEnd="310dp"
android:layout_marginBottom="639dp"
android:text="#string/DisplayDate"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<androidx.constraintlayout.widget.Guideline
android:id="#+id/guideline4"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
app:layout_constraintGuide_begin="20dp" />
<TextView
android:id="#+id/hamza_displaytime"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="29dp"
android:layout_marginTop="123dp"
android:layout_marginEnd="310dp"
android:layout_marginBottom="589dp"
android:text="#string/DisplayTime"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<ImageView
android:id="#+id/hamza_sweep_radient"
android:layout_width="200dp"
android:layout_height="200dp"
android:layout_marginStart="105dp"
android:layout_marginTop="425dp"
android:layout_marginEnd="106dp"
android:layout_marginBottom="106dp"
android:src="#drawable/sweep_gradient"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="1.0"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:layout_constraintVertical_bias="0.0" />
<TextView
android:id="#+id/text_sweep_radient"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="176dp"
android:layout_marginTop="356dp"
android:layout_marginEnd="177dp"
android:layout_marginBottom="356dp"
android:text="#string/Displaysweep_radient"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toTopOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
app_bar_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".HamzaActivity">
<com.google.android.material.appbar.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/Theme.HamzaAssign4.AppBarOverlay">
</com.google.android.material.appbar.AppBarLayout>
<include layout="#layout/content_main" />
<androidx.appcompat.widget.Toolbar
android:id="#+id/Hamza_toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="#dc6a3d"
app:popupTheme="#style/Theme.HamzaAssign4.PopupOverlay" />
</androidx.coordinatorlayout.widget.CoordinatorLayout>
activity_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".HamzaActivity">
<com.google.android.material.appbar.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/Theme.HamzaAssign4.AppBarOverlay">
</com.google.android.material.appbar.AppBarLayout>
<include layout="#layout/content_main" />
<androidx.appcompat.widget.Toolbar
android:id="#+id/Hamza_toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="#dc6a3d"
app:popupTheme="#style/Theme.HamzaAssign4.PopupOverlay" />
</androidx.coordinatorlayout.widget.CoordinatorLayout>
HamzaActivity.java (main java file)
//Made by Hamza Idlepi
package hamza.idlepi.n01361813;
import android.content.Intent;
import android.net.Uri;
import android.os.Bundle;
import android.view.MenuItem;
import android.view.View;
import android.view.Menu;
import com.google.android.material.snackbar.Snackbar;
import com.google.android.material.navigation.NavigationView;
import androidx.annotation.NonNull;
import androidx.appcompat.widget.Toolbar;
import androidx.navigation.NavController;
import androidx.navigation.Navigation;
import androidx.navigation.ui.AppBarConfiguration;
import androidx.navigation.ui.NavigationUI;
import androidx.drawerlayout.widget.DrawerLayout;
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.Toolbar;
import hamza.idlepi.n01361813.databinding.ActivityMainBinding;
public class HamzaActivity extends AppCompatActivity {
private AppBarConfiguration mAppBarConfiguration;
//private ActivityMainBinding binding;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = findViewById(R.id.Hamza_toolbar);
setSupportActionBar(toolbar);
DrawerLayout drawer = findViewById(R.id.Hamza_drawer_layout);
NavigationView navigationView = findViewById(R.id.Hamza_nav_view);
mAppBarConfiguration = new AppBarConfiguration.Builder(
R.id.nav_home, R.id.nav_gallery, R.id.nav_slideshow)
.setOpenableLayout(drawer)
.build();
NavController navController = Navigation.findNavController(this, R.id.Hamza_nav_host_fragment_content_main);
NavigationUI.setupActionBarWithNavController(this, navController, mAppBarConfiguration);
NavigationUI.setupWithNavController(navigationView, navController);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(#NonNull MenuItem item) {
int item_id = item.getItemId();
if (item_id == R.id.Hamza_Help){
startActivity(new Intent(Intent.ACTION_VIEW, Uri.parse("http://www.stackoverflow.com")));
}
else if(item_id==R.id.Hamza_action_settings){
startActivityForResult(new Intent(android.provider.Settings.ACTION_SETTINGS), 0);
}
return true;
}
#Override
public boolean onSupportNavigateUp() {
NavController navController = Navigation.findNavController(this, R.id.Hamza_nav_host_fragment_content_main);
return NavigationUI.navigateUp(navController, mAppBarConfiguration)
|| super.onSupportNavigateUp();
}
}
HomeFragment.java
package hamza.idlepi.n01361813.ui.home;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.fragment.app.Fragment;
import java.text.DateFormat;
import java.util.Calendar;
import hamza.idlepi.n01361813.R;
public class HomeFrag extends Fragment {
String Calendardate;
public View onCreateView(#NonNull LayoutInflater inflater,
ViewGroup container, Bundle savedInstanceState) {
View root = inflater.inflate(R.layout.home_fragment, container, false);
Calendar calendar = Calendar.getInstance();
Calendardate = DateFormat.getDateInstance(DateFormat.FULL).format(calendar.getTime());
TextView date = root.findViewById(R.id.homefrag_date);
//SimpleDateFormat mdformat = new SimpleDateFormat("HH:mm:ss");
//String strDate = "Current Time : " + mdformat.format(calendar.getTime());
//TextView textView = (TextView) root.findViewById(R.id.hamza_time);
//textView.setText(strDate);
date.setText(Calendardate);
return root;
}
}

navigation drawer made from android studio : android.view.InflateException: Error inflating class fragment

I am a complete beginner in android studio with java and I have run across this error which seems to be very frequent here . I have seen solutions but nothing has helped so far . In my code I have created a navigation drawer using the already made one from android studio . When I try to run the app I get :
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.covidmobileapp/com.example.covidmobileapp.MainActivity}: android.view.InflateException: Binary XML file line #15 in com.example.covidmobileapp:layout/activity_main: Binary XML file line #20 in com.example.covidmobileapp:layout/content_main: Error inflating class fragment
Which seems to spot errors in 2 xml files I have : activity_main.xml and content_main.xml
Goind down the stack trace it seems that the error hits when the app view is created
at com.example.covidmobileapp.MainActivity.onCreate(MainActivity.java:55)
This is my code for the files above :
MainActivity.java
package com.example.covidmobileapp;
import android.os.Bundle;
import android.view.View;
import android.view.Menu;
import com.google.android.material.snackbar.Snackbar;
import com.google.android.material.navigation.NavigationView;
import androidx.navigation.NavController;
import androidx.navigation.Navigation;
import androidx.navigation.ui.AppBarConfiguration;
import androidx.navigation.ui.NavigationUI;
import androidx.drawerlayout.widget.DrawerLayout;
import androidx.appcompat.app.AppCompatActivity;
import com.example.covidmobileapp.databinding.ActivityMainBinding;
public class MainActivity extends AppCompatActivity {
private AppBarConfiguration mAppBarConfiguration;
private ActivityMainBinding binding;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
binding = ActivityMainBinding.inflate(getLayoutInflater());
setContentView(binding.getRoot());
setSupportActionBar(binding.appBarMain.toolbar);
binding.appBarMain.fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
DrawerLayout drawer = binding.drawerLayout;
NavigationView navigationView = binding.navView;
// Passing each menu ID as a set of Ids because each
// menu should be considered as top level destinations.
mAppBarConfiguration = new AppBarConfiguration.Builder(
R.id.nav_home, R.id.nav_gallery, R.id.nav_slideshow , R.id.nav_homepage)
.setDrawerLayout(drawer)
.build();
NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment_content_main);
NavigationUI.setupActionBarWithNavController(this, navController, mAppBarConfiguration);
NavigationUI.setupWithNavController(navigationView, navController);
setContentView(R.layout.activity_main);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public boolean onSupportNavigateUp() {
NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment_content_main);
return NavigationUI.navigateUp(navController, mAppBarConfiguration)
|| super.onSupportNavigateUp();
}
}
content_main.xml I have commented the line where the fragment error hits
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 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:layout_width="match_parent"
android:layout_height="match_parent"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:showIn="#layout/app_bar_main">
<fragment
android:id="#+id/nav_host_fragment_content_main"
android:name="androidx.navigation.fragment.NavHostFragment"
android:layout_width="match_parent"
android:layout_height="match_parent"
app:defaultNavHost="true"
app:layout_constraintHorizontal_bias="0.0"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent"
app:navGraph="#navigation/mobile_navigation" //this is where the fragment error hits
/>
</androidx.constraintlayout.widget.ConstraintLayout>
activity_main.xml I have also commented where the error is here
<?xml version="1.0" encoding="utf-8"?>
<androidx.drawerlayout.widget.DrawerLayout 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/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:openDrawer="start">
<include
android:id="#+id/app_bar_main"
layout="#layout/app_bar_main"
android:layout_width="match_parent"
android:layout_height="match_parent" /> //this is where error for activity_main is
<com.google.android.material.navigation.NavigationView
android:id="#+id/nav_view"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_gravity="start"
android:fitsSystemWindows="true"
app:headerLayout="#layout/nav_header_main"
app:menu="#menu/activity_main_drawer" />
</androidx.drawerlayout.widget.DrawerLayout>
I would appreciate your help as this is really frustrating . If more info is needed I will upload it .

I think you should declare:
NavigationView leftNavigationView;
in your main activity and get you nav view in on create method:
leftNavigationView = findViewById(R.id.nav_view);
setLeftNavigationView();
Then you havae to use setNavigationItemSelectedListener. You can create a method like this:
private void setLeftNavigationView() {
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
this,
drawerLayout,
toolbar,
R.string.navigation_drawer_open,
R.string.navigation_drawer_close);
drawerLayout.addDrawerListener(toggle);
toggle.syncState();
leftNavigationView.setNavigationItemSelectedListener(item -> {
Fragment selectedFragment = null;
switch (item.getItemId()) {
case R.id.nav_yourFragment:
selectedFragment = new YourFragment();
drawerLayout.closeDrawer(GravityCompat.START);
break;
}
getSupportFragmentManager()
.beginTransaction()
.replace(R.id.fragment_container, selectedFragment).addToBackStack("tag")
.commit();
return true;
});
and so on. R.id.nav_yourFragment is your item from your menu
Also you have to put a FrameLayout container in your xml file:
<FrameLayout
android:id="#+id/fragment_container"
android:layout_width="match_parent"
android:layout_height="match_parent" />
I hope this is useful for you

Removing AppBar SearchView Hint Icon

I'm trying to remove the icon in the hint of my app bar search view.
View of what i have
So i would like to remove the magnifying glass in the searchView.
I'm a beginner in android.
Here is my main activity layout
<?xml version="1.0" encoding="utf-8"?>
<androidx.drawerlayout.widget.DrawerLayout 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/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:openDrawer="start">
<include
layout="#layout/app_bar_main"
android:layout_width="match_parent"
android:layout_height="match_parent" />
...
</androidx.drawerlayout.widget.DrawerLayout>
Here is the app_bar_main.xml
<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.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:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity">
<androidx.cardview.widget.CardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="10dp">
<com.google.android.material.appbar.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/AppTheme.AppBarOverlay">
<androidx.appcompat.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="#color/colorWhite"
app:subtitleTextColor="#color/colorPrimary"
app:titleTextColor="#color/colorPrimary"
app:popupTheme="#style/AppTheme.Toolbar"
app:theme="#style/AppTheme.Icons" />
</com.google.android.material.appbar.AppBarLayout>
</androidx.cardview.widget.CardView>
<include layout="#layout/content_main" />
<com.google.android.material.floatingactionbutton.FloatingActionButton
android:id="#+id/fab"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="bottom|end"
android:layout_margin="#dimen/fab_margin"
app:srcCompat="#android:drawable/ic_dialog_email" />
</androidx.coordinatorlayout.widget.CoordinatorLayout>
Here is my main.xml
<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto">
<item
android:id="#+id/search"
android:title="Recherche"
android:icon="#drawable/ic_search"
app:showAsAction="ifRoom"
app:actionViewClass="android.widget.SearchView"/>
</menu>
Here is my searchable.xml
<?xml version="1.0" encoding="utf-8"?>
<searchable xmlns:android="http://schemas.android.com/apk/res/android"
android:label="#string/app_name"
android:hint="#string/search_hint"
android:voiceSearchMode="showVoiceSearchButton|launchRecognizer"
/>
And here is my Activity java
package com.example.test3;
import android.app.SearchManager;
import android.content.Context;
import android.graphics.Color;
import android.os.Bundle;
import com.google.android.material.floatingactionbutton.FloatingActionButton;
import com.google.android.material.snackbar.Snackbar;
import android.view.MenuInflater;
import android.view.View;
import androidx.navigation.NavController;
import androidx.navigation.Navigation;
import androidx.navigation.ui.AppBarConfiguration;
import androidx.navigation.ui.NavigationUI;
import com.google.android.material.navigation.NavigationView;
import androidx.drawerlayout.widget.DrawerLayout;
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.widget.Toolbar;
import android.view.Menu;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.SearchView;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity {
private AppBarConfiguration mAppBarConfiguration;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
FloatingActionButton fab = findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
DrawerLayout drawer = findViewById(R.id.drawer_layout);
NavigationView navigationView = findViewById(R.id.nav_view);
// Passing each menu ID as a set of Ids because each
// menu should be considered as top level destinations.
mAppBarConfiguration = new AppBarConfiguration.Builder(
R.id.nav_home, R.id.nav_gallery, R.id.nav_slideshow,
R.id.nav_tools, R.id.nav_share, R.id.nav_send)
.setDrawerLayout(drawer)
.build();
NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
NavigationUI.setupActionBarWithNavController(this, navController, mAppBarConfiguration);
NavigationUI.setupWithNavController(navigationView, navController);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
MenuInflater inflater = getMenuInflater();
inflater.inflate(R.menu.main, menu);
SearchManager searchManager = (SearchManager)getSystemService(Context.SEARCH_SERVICE);
SearchView searchView = (SearchView)menu.findItem(R.id.search).getActionView();
searchView.setSearchableInfo(searchManager.getSearchableInfo(getComponentName()));
System.out.println(searchManager.getSearchableInfo(getComponentName()));
int searchPlateId = searchView.getContext().getResources().getIdentifier("android:id/search_plate", null, null);
View searchPlate = searchView.findViewById(searchPlateId);
searchPlate.setBackgroundColor(Color.TRANSPARENT);
int submitAreaId = searchView.getContext().getResources().getIdentifier("android:id/submit_area", null, null);
View submitAreaView = searchView.findViewById(submitAreaId);
submitAreaView.setBackgroundColor(Color.TRANSPARENT);
return true;
}
#Override
public boolean onSupportNavigateUp() {
NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
return NavigationUI.navigateUp(navController, mAppBarConfiguration)
|| super.onSupportNavigateUp();
}
}
I can't find out what i'm supposed to edit to remove this icon
Thank your for your answers
EDIT : If it's easier for you here is the github https://github.com/BenoitBonavia/geoloc-indoor-application

Found it !
In my activity.java in the onCreateOptionsMenu method i added this :
int magId = getResources().getIdentifier("android:id/search_mag_icon", null, null);
ImageView magImage = searchView.findViewById(magId);
magImage.setLayoutParams(new LinearLayout.LayoutParams(0, 0));

Content not shown when recycler view is placed below AppBarLayout

I'm making an app where the activity has this layout (which I got off a guide) and its perfect because this is what I wanted. But since I have been unable to display data in it - as you can see with the recycler view put in the layout file.
Here's the layout
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/drawer"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true">
<android.support.design.widget.CoordinatorLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/main_content"
android:layout_width="match_parent"
android:layout_height="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/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:layout_scrollFlags="scroll|enterAlways"
app:popupTheme="#style/ThemeOverlay.AppCompat.Light" />
</android.support.design.widget.AppBarLayout>
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:scrollbars="vertical" />
<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>
<android.support.design.widget.NavigationView
android:id="#+id/nav_view"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:layout_gravity="start"
android:fitsSystemWindows="true"
app:headerLayout="#layout/navheader"
app:menu="#menu/menu_navigation" />
Here's the activity which runs everything:
import android.support.design.widget.NavigationView;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBar;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.support.v7.widget.DefaultItemAnimator;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.Toolbar;
import android.view.MenuItem;
import java.util.ArrayList;
import java.util.List;
public class basics_list extends AppCompatActivity {
private DrawerLayout mDrawerLayout;
private List<Basic> basicList = new ArrayList<>();
private RecyclerView recyclerView;
private BasicsAdapter mAdapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setTitle(R.string.basics_list_name);
setContentView(R.layout.activity_basics_list);
// Adding Toolbar to Main screen
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
// set recycler view
recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
mAdapter = new BasicsAdapter(basicList);
final RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager(getApplicationContext());
recyclerView.setLayoutManager(mLayoutManager);
recyclerView.setItemAnimator(new DefaultItemAnimator());
recyclerView.setAdapter(mAdapter);
prepareBasicsData();
// Create Navigation drawer and inflate layout
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer);
// Adding menu icon to Toolbar
ActionBar supportActionBar = getSupportActionBar();
if (supportActionBar != null) {
supportActionBar.setHomeAsUpIndicator(R.drawable.ic_menu_white_24dp);
supportActionBar.setDisplayHomeAsUpEnabled(true);
}
// Set behavior of Navigation drawer
navigationView.setNavigationItemSelectedListener(
new NavigationView.OnNavigationItemSelectedListener() {
// This method will trigger on item Click of navigation menu
#Override
public boolean onNavigationItemSelected(MenuItem menuItem) {
// Set item in checked state
menuItem.setChecked(true);
// TODO: handle navigation
// Closing drawer on item click
mDrawerLayout.closeDrawers();
return true;
}
});
}
private void prepareBasicsData() {
Basic basic = new Basic("one");
basicList.add(basic);
basic = new Basic("two");
basicList.add(basic);
basic = new Basic("three");
basicList.add(basic);
mAdapter.notifyDataSetChanged();
}
}

Try adding a layout_behavior to your RecyclerView
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler_view"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
android:scrollbars="vertical" />
See this question for more about placing views within CoordinatorLayouts

Android App Crash On Button Click

I am building an app and on a button click the app crashes. The app was working perfectly about a week ago and the code has not been altered in anyway since the last time I tested it. Now when I click the Login in button it crashes. This makes no sense as it hasn't been edited. Source code below.
Login.java
package com.example.martin.ivebeenthere;
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.View;
public class Login extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
}
public void onClickbtnFeed(View view)
{
startActivity(new Intent(Login.this, Feed.class));
}
}
content_login.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout 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:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:context="com.example.martin.ivebeenthere.Login"
tools:showIn="#layout/activity_login">
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/imageView"
android:src="#drawable/logo"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginBottom="276dp" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="textPersonName"
android:ems="10"
android:hint="Username"
android:id="#+id/editText"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="textPassword"
android:ems="10"
android:hint="Password"
android:id="#+id/editText2"
android:layout_below="#+id/editText"
android:layout_centerHorizontal="true" />
<Button
android:layout_width="200dp"
android:layout_height="wrap_content"
android:text="Login"
android:id="#+id/button3"
android:layout_below="#+id/editText2"
android:layout_centerHorizontal="true"
android:onClick="onClickbtnFeed"/>
<Button
android:layout_width="200dp"
android:layout_height="wrap_content"
android:text="Login With Facebook"
android:id="#+id/button4"
android:background="#3b5998"
android:textColor="#ffffff"
android:layout_below="#+id/button3"
android:layout_alignLeft="#+id/button3"
android:layout_alignStart="#+id/button3"
android:layout_marginTop="25dp" />
</RelativeLayout>
Feed.java (Page Linked With Button)
package com.example.martin.ivebeenthere;
import android.content.Intent;
import android.os.Bundle;
import android.support.design.widget.FloatingActionButton;
import android.support.design.widget.Snackbar;
import android.view.View;
import android.support.design.widget.NavigationView;
import android.support.v4.view.GravityCompat;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarDrawerToggle;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ListView;
import android.widget.Toast;
public class Feed extends AppCompatActivity
implements NavigationView.OnNavigationItemSelectedListener {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_feed);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
drawer.setDrawerListener(toggle);
toggle.syncState();
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
navigationView.setNavigationItemSelectedListener(this);
String[] users = {"\nMartin Hoban\n\nVisited Dublin 2 Hours Ago\n","\nJack White\n\nVisited Mayo 10 Hours Ago\n","\nSarah Cox\n\nVisited Cork 1 Day Ago\n","\nMalcolm Holmes\n\nVisited Knock 2 Days Ago\n", "\nCraig Fisher\n\nVisited The Spire 2 Days Ago\n", "\nHannah Smith\n\nVisited Mayo 3 Days Ago\n"
,"\nLanelle Delaune\n\nVisited Limerick 1 Week Ago\n", "\nHanna Whitlow\n\nVisited Paris 1 Week Ago\n", "\nMoses Primm\n\nVisited Italy 3 Weeks Ago\n", "\nBerta Pedraza\n\nVisited The Aillwee Caves 1 Month Ago\n"};
ArrayAdapter<String> itemsAdapter =
new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, users);
ListView listView = (ListView) findViewById(R.id.listView);
listView.setAdapter(itemsAdapter);
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
if (position == 4) {
Intent myIntent = new Intent(view.getContext(), CheckinInfo.class);
startActivityForResult(myIntent, 0);
}
}
});
}
#Override
public void onBackPressed() {
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
if (drawer.isDrawerOpen(GravityCompat.START)) {
drawer.closeDrawer(GravityCompat.START);
} else {
super.onBackPressed();
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.feed, menu);
return true;
}
#SuppressWarnings("StatementWithEmptyBody")
#Override
public boolean onNavigationItemSelected(MenuItem item) {
// Handle navigation view item clicks here.
int id = item.getItemId();
if (id == R.id.nav_feed) {
startActivity(new Intent(getApplicationContext(), Feed.class));
} else if (id == R.id.nav_map) {
startActivity(new Intent(getApplicationContext(), Map.class));
} else if (id == R.id.nav_account) {
startActivity(new Intent(getApplicationContext(), Account.class));
} else if (id == R.id.nav_logout) {
startActivity(new Intent(getApplicationContext(), Home.class));
Toast.makeText(getApplicationContext(), "Logged Out",
Toast.LENGTH_LONG).show();
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
return true;
}
}
Logcat
Caused by: java.lang.NullPointerException
at com.example.martin.ivebeenthere.Feed.onCreate(Feed.java:38)
at android.app.Activity.performCreate(Activity.java:5047)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1094)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2056)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2117) 
at android.app.ActivityThread.access$700(ActivityThread.java:134) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1218) 
at android.os.Handler.dispatchMessage(Handler.java:99) 
at android.os.Looper.loop(Looper.java:137) 
at android.app.ActivityThread.main(ActivityThread.java:4867) 
at java.lang.reflect.Method.invokeNative(Native Method) 
at java.lang.reflect.Method.invoke(Method.java:511) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1007)at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:774) 
at dalvik.system.NativeStart.main(Native Method)
activity_feed.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout 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/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:openDrawer="start">
<include
layout="#layout/app_bar_feed"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</android.support.v4.widget.DrawerLayout>
app_bar_feed.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:layout_width="match_parent"
android:layout_height="match_parent"
android:fitsSystemWindows="true"
tools:context="com.example.martin.ivebeenthere.Feed">
<android.support.design.widget.AppBarLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:theme="#style/AppTheme.AppBarOverlay">
<android.support.v7.widget.Toolbar
android:id="#+id/toolbar"
android:layout_width="match_parent"
android:layout_height="?attr/actionBarSize"
android:background="?attr/colorPrimary"
app:popupTheme="#style/AppTheme.PopupOverlay" />
</android.support.design.widget.AppBarLayout>
<include layout="#layout/content_feed" />
</android.support.design.widget.CoordinatorLayout>
Rendering Problem In Design View of activity_feed.xml
java.lang.IllegalArgumentException: No drawer view found with gravity LEFT
at android.support.v4.widget.DrawerLayout.openDrawer(DrawerLayout.java:1464)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at com.android.layoutlib.bridge.util.ReflectionUtils.invoke(ReflectionUtils.java:45)
at com.android.layoutlib.bridge.android.support.DrawerLayoutUtil.openDrawer(DrawerLayoutUtil.java:56)
at com.android.layoutlib.bridge.android.support.DrawerLayoutUtil.openDrawer(DrawerLayoutUtil.java:50)
at android.view.BridgeInflater.postInflateProcess(BridgeInflater.java:361)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.postInflateProcess(RenderSessionImpl.java:968)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.postInflateProcess(RenderSessionImpl.java:973)
at com.android.layoutlib.bridge.impl.RenderSessionImpl.inflate(RenderSessionImpl.java:235)
at com.android.layoutlib.bridge.Bridge.createSession(Bridge.java:426)
at com.android.ide.common.rendering.LayoutLibrary.createSession(LayoutLibrary.java:350)
at com.android.tools.idea.rendering.RenderTask$2.compute(RenderTask.java:510)
at com.android.tools.idea.rendering.RenderTask$2.compute(RenderTask.java:498)
at com.intellij.openapi.application.impl.ApplicationImpl.runReadAction(ApplicationImpl.java:888)
at com.android.tools.idea.rendering.RenderTask.createRenderSession(RenderTask.java:498)
at com.android.tools.idea.rendering.RenderTask.access$600(RenderTask.java:72)
at com.android.tools.idea.rendering.RenderTask$3.call(RenderTask.java:610)
at com.android.tools.idea.rendering.RenderTask$3.call(RenderTask.java:607)
at com.android.tools.idea.rendering.RenderService.runRenderAction(RenderService.java:362)
at com.android.tools.idea.rendering.RenderTask.render(RenderTask.java:607)
at com.android.tools.idea.rendering.RenderTask.render(RenderTask.java:629)
at com.intellij.android.designer.designSurface.AndroidDesignerEditorPanel$6.run(AndroidDesignerEditorPanel.java:480)
at com.intellij.util.ui.update.MergingUpdateQueue.execute(MergingUpdateQueue.java:320)
at com.intellij.util.ui.update.MergingUpdateQueue.execute(MergingUpdateQueue.java:310)
at com.intellij.util.ui.update.MergingUpdateQueue$2.run(MergingUpdateQueue.java:254)
at com.intellij.util.ui.update.MergingUpdateQueue.flush(MergingUpdateQueue.java:269)
at com.intellij.util.ui.update.MergingUpdateQueue.flush(MergingUpdateQueue.java:227)
at com.intellij.util.ui.update.MergingUpdateQueue.run(MergingUpdateQueue.java:217)
at com.intellij.util.concurrency.QueueProcessor.runSafely(QueueProcessor.java:238)
at com.intellij.util.Alarm$Request$1.run(Alarm.java:351)
at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
at java.util.concurrent.FutureTask.run(FutureTask.java:266)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)

I think that the referenced dimension resource can't be found.
The reason may be, you have dimensions specified for specific screen sizes only.
your content.xml:
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
define them in values-820dp/dimens.xml or define them in content.xml
you can remove them too.

The local variable navigationView is null. That means there's no view with id nav_view in your activity_feed layout. Make sure to include all views you try to find with findViewById() in onCreate() into the layout.