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Force closing after Splash Screen Android apps

This is the Logcat. plese help:(
07-19 09:39:48.815 9001-9001/pens.pensnews E/AndroidRuntime: FATAL EXCEPTION: main
Process: pens.pensnews, PID: 9001
java.lang.RuntimeException: Unable to start activity ComponentInfo{pens.pensnews/pens.pensnews.MainActivity}: java.lang.IllegalStateException: This Activity already has an action bar supplied by the window decor. Do not request Window.FEATURE_SUPPORT_ACTION_BAR and set windowActionBar to false in your theme to use a Toolbar instead.
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3319)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3415)
at android.app.ActivityThread.access$1100(ActivityThread.java:229)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1821)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:148)
at android.app.ActivityThread.main(ActivityThread.java:7325)
at java.lang.reflect.Method.invoke(Native Method)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120)
Caused by: java.lang.IllegalStateException: This Activity already has an action bar supplied by the window decor. Do not request Window.FEATURE_SUPPORT_ACTION_BAR and set windowActionBar to false in your theme to use a Toolbar instead.
at android.support.v7.app.AppCompatDelegateImplV9.setSupportActionBar(AppCompatDelegateImplV9.java:204)
at android.support.v7.app.AppCompatActivity.setSupportActionBar(AppCompatActivity.java:129)
at pens.pensnews.MainActivity.onCreate(MainActivity.java:25)
at android.app.Activity.performCreate(Activity.java:6904)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1136)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:3266)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:3415) 
at android.app.ActivityThread.access$1100(ActivityThread.java:229) 
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1821) 
at android.os.Handler.dispatchMessage(Handler.java:102) 
at android.os.Looper.loop(Looper.java:148) 
at android.app.ActivityThread.main(ActivityThread.java:7325) 
at java.lang.reflect.Method.invoke(Native Method) 
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1230) 
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1120) 
I implemented a splash screen to launch before my main activity. Before I put the Splash Screen, it worked. I am not sure where I am going wrong or what I missed.
This is my code
Splashscreen.java :
package pens.pensnews;import android.app.Activity;import android.content.Intent;import android.os.Bundle;import android.os.Handler;import android.view.Window;import android.view.WindowManager;
public class Splashscreen extends Activity {
//Set waktu lama splashscreen
private static int splashInterval = 2000;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.activity_splashscreen);
new Handler().postDelayed(new Runnable(){
#Override
public void run() {
// TODO Auto-generated method stub
Intent i = new Intent(getApplicationContext(), MainActivity.class);
startActivity(i); // menghubungkan activity splashscreen ke main activity dengan intent
//jeda selesai Splashscreen
finish();
}
}, splashInterval);
}}
MainActivity.java
package pens.pensnews;import android.os.Bundle;import android.support.design.widget.FloatingActionButton;import android.support.design.widget.Snackbar;import android.support.v4.app.FragmentManager;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.view.View;
public class MainActivity extends AppCompatActivity
implements NavigationView.OnNavigationItemSelectedListener {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
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);
FragmentManager manager = getSupportFragmentManager();
Kampus kampus = new Kampus();
manager.beginTransaction().replace(R.id.MainLayout, kampus).commit();
Akademik akademik = new Akademik();
manager.beginTransaction().replace(R.id.MainLayout, akademik).commit();
Nonak nonak = new Nonak();
manager.beginTransaction().replace(R.id.MainLayout, nonak).commit();
Beranda beranda = new Beranda();
manager.beginTransaction().replace(R.id.MainLayout, beranda).commit();
}
#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.main, menu);
return true;
}
#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.nav_help) {
return true;
}
return super.onOptionsItemSelected(item);}
#SuppressWarnings("StatementWithEmptyBody")
#Override
public boolean onNavigationItemSelected(MenuItem item) {
// Handle navigation view item clicks here.
int id = item.getItemId();
if (id == R.id.nav_beranda) {
Beranda beranda = new Beranda();
FragmentManager manager = getSupportFragmentManager();
manager.beginTransaction().replace(R.id.MainLayout, beranda).commit();
} else if (id == R.id.nav_kampus) {
Kampus kampus = new Kampus();
FragmentManager manager = getSupportFragmentManager();
manager.beginTransaction().replace(R.id.MainLayout, kampus).commit();
} else if (id == R.id.nav_akademik) {
Akademik akademik = new Akademik();
FragmentManager manager = getSupportFragmentManager();
manager.beginTransaction().replace(R.id.MainLayout, akademik).commit();
}else if (id == R.id.nav_non) {
Nonak nonak = new Nonak();
FragmentManager manager = getSupportFragmentManager();
manager.beginTransaction().replace(R.id.MainLayout, nonak).commit();
} else if (id == R.id.nav_about) {
About about = new About();
FragmentManager manager = getSupportFragmentManager();
manager.beginTransaction().replace(R.id.MainLayout, about).commit();
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
return true;
}}
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="pens.pensnews">
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:theme="#style/AppTheme">
<activity
android:name="pens.pensnews.Splashscreen"
android:label="#string/app_name"
android:theme="#style/Splashscreen"
android:noHistory="true">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="pens.pensnews.MainActivity"
android:label="#string/app_name" >
</activity>
<activity android:name=".Mawapres" />
<activity android:name=".Akademik1" />
<activity android:name=".Akademik2" />
<activity android:name=".Kampus1" />
<activity android:name=".Kampus2" />
<activity android:name=".Kampus3" />
<activity android:name=".Nonak1" />
<activity android:name=".Nonak2" />
<activity android:name=".Nonak3" />
<activity android:name=".Nonak4"></activity>
</application>
</manifest>
MainActivity.java
package pens.pensnews;import android.os.Bundle;import android.support.design.widget.FloatingActionButton;import android.support.design.widget.Snackbar;import android.support.v4.app.FragmentManager;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.view.View;
public class MainActivity extends AppCompatActivity
implements NavigationView.OnNavigationItemSelectedListener {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
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);
FragmentManager manager = getSupportFragmentManager();
Kampus kampus = new Kampus();
manager.beginTransaction().replace(R.id.MainLayout, kampus).commit();
Akademik akademik = new Akademik();
manager.beginTransaction().replace(R.id.MainLayout, akademik).commit();
Nonak nonak = new Nonak();
manager.beginTransaction().replace(R.id.MainLayout, nonak).commit();
Beranda beranda = new Beranda();
manager.beginTransaction().replace(R.id.MainLayout, beranda).commit();
}
#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.main, menu);
return true;
}
#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.nav_help) {
return true;
}
return super.onOptionsItemSelected(item);}
#SuppressWarnings("StatementWithEmptyBody")
#Override
public boolean onNavigationItemSelected(MenuItem item) {
// Handle navigation view item clicks here.
int id = item.getItemId();
if (id == R.id.nav_beranda) {
Beranda beranda = new Beranda();
FragmentManager manager = getSupportFragmentManager();
manager.beginTransaction().replace(R.id.MainLayout, beranda).commit();
} else if (id == R.id.nav_kampus) {
Kampus kampus = new Kampus();
FragmentManager manager = getSupportFragmentManager();
manager.beginTransaction().replace(R.id.MainLayout, kampus).commit();
} else if (id == R.id.nav_akademik) {
Akademik akademik = new Akademik();
FragmentManager manager = getSupportFragmentManager();
manager.beginTransaction().replace(R.id.MainLayout, akademik).commit();
}else if (id == R.id.nav_non) {
Nonak nonak = new Nonak();
FragmentManager manager = getSupportFragmentManager();
manager.beginTransaction().replace(R.id.MainLayout, nonak).commit();
} else if (id == R.id.nav_about) {
About about = new About();
FragmentManager manager = getSupportFragmentManager();
manager.beginTransaction().replace(R.id.MainLayout, about).commit();
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
return true;
}}
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="pens.pensnews">
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
android:theme="#style/AppTheme">
<activity
android:name="pens.pensnews.Splashscreen"
android:label="#string/app_name"
android:theme="#style/Splashscreen"
android:noHistory="true">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="pens.pensnews.MainActivity"
android:label="#string/app_name" >
</activity>
<activity android:name=".Mawapres" />
<activity android:name=".Akademik1" />
<activity android:name=".Akademik2" />
<activity android:name=".Kampus1" />
<activity android:name=".Kampus2" />
<activity android:name=".Kampus3" />
<activity android:name=".Nonak1" />
<activity android:name=".Nonak2" />
<activity android:name=".Nonak3" />
<activity android:name=".Nonak4"></activity>
</application>
</manifest>

Add This line in your AndroidManifest.xml
android:theme="#style/AppTheme.NoActionBar"
after adding this line your file look like this..
<activity
android:name="pens.pensnews.Splashscreen"
android:label="#string/app_name"
android:theme="#style/Splashscreen"
android:theme="#style/AppTheme.NoActionBar"
android:noHistory="true">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
Shiena if this code is work for you then mark this question as your answer.

Attempt to invoke virtual method 'void android.app.ActionBar.setHomeButtonEnabled(boolean)' on a null object reference

I have seen other soution but i think my situation is diffrent . , I am trying to implement
ActionBar with Tabs from this example ;
http://www.androidgreeve.com/2014/01/android-actionbar-navigating-with-swipeable-tabs-and-views.html
on
actionBar.setHomeButtonEnabled(false);
program throws error :
Attempt to invoke virtual method 'void
android.app.ActionBar.setHomeButtonEnabled(boolean)' on a null object
reference
here is the code
package com.example.administrator.fragmentsexample;
import android.app.ActionBar;
import android.app.FragmentTransaction;
import android.support.v4.app.FragmentActivity;
import android.support.v4.view.ViewPager;
import android.os.Bundle;
import android.support.v7.app.ActionBarActivity;
import android.view.Menu;
import android.view.MenuItem;
import com.example.administrator.adapter.TabsPagerAdapter;
public class MainActivity extends FragmentActivity implements
ActionBar.TabListener {
private ViewPager viewPager;
private TabsPagerAdapter mAdapter;
private ActionBar actionBar;
// Tab titles
private String[] tabs = {"Social", "Organizer", "Movies"};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Initilization
viewPager = (ViewPager) findViewById(R.id.pager);
actionBar = getSupportActionBar();
mAdapter = new TabsPagerAdapter(getSupportFragmentManager());
viewPager.setAdapter(mAdapter);
actionBar.setHomeButtonEnabled(false);
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
// Adding Tabs
for (String tab_name : tabs) {
actionBar.addTab(actionBar.newTab().setText(tab_name)
.setTabListener(this));
}
}
#Override
public void onTabSelected(ActionBar.Tab tab, FragmentTransaction ft) {
}
#Override
public void onTabUnselected(ActionBar.Tab tab, FragmentTransaction ft) {
}
#Override
public void onTabReselected(ActionBar.Tab tab, FragmentTransaction ft) {
}
}
My Manifest File :
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.administrator.fragmentsexample" >
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
I tried to replace FragmentActivity with ActioBarActivity but it is shoing deprecated API Error
i think I am missing very basic thing .. what am I missing in code ?

FragmentActivity out of support.v4 is not including a SupportActionBar, this why you get Null Reference.
Change your class definition to extend AppCompatActivity which extends FragmentActivity like so:
public class MainActivity extends AppCompatActivity implements
ActionBar.TabListener {
...
}
Change your Import of ActionBar to:
import android.support.v7.app.ActionBar
Because like the API Docs said: http://developer.android.com/reference/android/support/v7/app/AppCompatActivity.html#getSupportActionBar()
It returns the support library version of the ActionBar impl. ;)
Attention!
Regarding Deprecated mark on SupportActionBarActivity I changed extend to AppCompatActivity.
Thats all.

Change ActionBarAtivity to AppCompatActivity

Null Pointer Exception with the actionBar

I have implemented swipe view but I am getting a Null Poitner Exception and the logcat says:
Caused by: java.lang.NullPointerException: Attempt to invoke virtual
method 'android.app.ActionBar$Tab android.app.ActionBar.newTab()' on a
null object reference at
com.example.android.mainactivityiit.MainActivity.onCreate(MainActivity.java:37)
I have been through numerous answers for the same question but none solved my issue. I changed the getActionBar to getSupportActionBar but still the error stays. Pleaase help me at the earliest.
here is my code:(Edited latest code)
package com.example.android.mainactivityiit;
import android.app.ActionBar;
import android.app.ActionBar.Tab;
import android.app.FragmentTransaction;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.view.ViewPager;
public class MainActivity extends FragmentActivity implements
ActionBar.TabListener {
private ViewPager viewPager;
private TabsPagerAdapter mAdapter;
private ActionBar actionBar;
// Tab titles
private String[] tabs = { "Top Rated", "Games", "Movies" };
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// Initilization
viewPager = (ViewPager) findViewById(R.id.pager);
actionBar = getActionBar();
mAdapter = new TabsPagerAdapter(getSupportFragmentManager());
viewPager.setAdapter(mAdapter);
actionBar.setHomeButtonEnabled(false);
actionBar.setNavigationMode(ActionBar.NAVIGATION_MODE_TABS);
// Adding Tabs
for (String tab_name : tabs) {
actionBar.addTab(actionBar.newTab().setText(tab_name)
.setTabListener(this));
}
/**
* on swiping the viewpager make respective tab selected
* */
viewPager.setOnPageChangeListener(new ViewPager.OnPageChangeListener() {
#Override
public void onPageSelected(int position) {
// on changing the page
// make respected tab selected
actionBar.setSelectedNavigationItem(position);
}
#Override
public void onPageScrolled(int arg0, float arg1, int arg2) {
}
#Override
public void onPageScrollStateChanged(int arg0) {
}
});
}
#Override
public void onTabReselected(Tab tab, FragmentTransaction ft) {
}
#Override
public void onTabSelected(Tab tab, FragmentTransaction ft) {
// on tab selected
// show respected fragment view
viewPager.setCurrentItem(tab.getPosition());
}
#Override
public void onTabUnselected(Tab tab, FragmentTransaction ft) {
}
}
this is tabspageadapter:
package com.example.android.mainactivityiit;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentPagerAdapter;
public class TabsPagerAdapter extends FragmentPagerAdapter {
public TabsPagerAdapter(FragmentManager fm) {
super(fm);
}
#Override
public Fragment getItem(int index) {
switch (index) {
case 0:
// Top Rated fragment activity
return new TopRatedFragment();
case 1:
// Games fragment activity
return new GamesFragment();
case 2:
// Movies fragment activity
return new MoviesFragment();
}
return null;
}
#Override
public int getCount() {
// get item count - equal to number of tabs
return 3;
}
}
I have implemented this activity using intent so the manifest file is for the other activity from which I am calling the swipe view activity.
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.android.mainactivityiit" >
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MainActivityiit"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>

Change following line
actionBar = getActionBar();
to
actionBar = getSupportActionBar();
UPDATE :
you have to import android.support.v7.app.actionBar not android.app.actionBar.
hope this will helps you.

App stops working when I call a second activity with nav drawer from nav drawer click

Okay so I want to have the navigation drawer available to use from all activities. I am creating a soundboard app and when I click on item 0 on the list I want it to take me to the first activity which has a navigation drawer and the first soundboard activity in it. The from that activity I want to open the nav drawer and click on another item on the list and it can take me to that activity with a soundboard in and so on... I have the nav drawer work fine when the app opens but when I click on position 0 for it to take me to another activity with the soundboard in the app closes as it has stopped working. What have I done wrong? How would I correct it to work.
This is my main activity code that opens when the app is launched:
public class MainActivity extends ActionBarActivity {
DrawerLayout mDrawerLayout;
ListView mDrawerList;
ActionBarDrawerToggle mDrawerToggle;
String[] mDrawerListItems;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Toolbar toolbar = (Toolbar)findViewById(R.id.toolbar);
mDrawerLayout = (DrawerLayout)findViewById(R.id.drawer);
mDrawerList = (ListView)findViewById(android.R.id.list);
mDrawerListItems = getResources().getStringArray(R.array.drawer_list);
mDrawerList.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, mDrawerListItems));
mDrawerList.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
switch(position) {
case 0:
Intent i = new Intent(MainActivity.this, MrsClubb.class);
startActivity(i);
}
mDrawerLayout.closeDrawer(mDrawerList);
}
});
mDrawerToggle = new ActionBarDrawerToggle(this,
mDrawerLayout,
toolbar,
R.string.drawer_open,
R.string.drawer_close){
public void onDrawerClosed(View v){
super.onDrawerClosed(v);
invalidateOptionsMenu();
syncState();
}
public void onDrawerOpened(View v){
super.onDrawerOpened(v);
invalidateOptionsMenu();
syncState();
}
};
mDrawerLayout.setDrawerListener(mDrawerToggle);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setHomeButtonEnabled(true);
mDrawerToggle.syncState();
}
#Override
protected void onPostCreate(Bundle savedInstanceState){
super.onPostCreate(savedInstanceState);
mDrawerToggle.syncState();
}
#Override
public void onConfigurationChanged(Configuration newConfig){
super.onConfigurationChanged(newConfig);
mDrawerToggle.onConfigurationChanged(newConfig);
}
#Override
public boolean onOptionsItemSelected(MenuItem item){
switch (item.getItemId()){
case android.R.id.home: {
if (mDrawerLayout.isDrawerOpen(mDrawerList)){
mDrawerLayout.closeDrawer(mDrawerList);
} else {
mDrawerLayout.openDrawer(mDrawerList);
}
return true;
}
default: return super.onOptionsItemSelected(item);
}
}
}
This is my second class that I wish the position 0 on the list view to take me to with the soundboard in:
public class MrsClubb extends ActionBarActivity {
DrawerLayout mDrawerLayout;
ListView mDrawerList;
ActionBarDrawerToggle mDrawerToggle;
String[] mDrawerListItems;
SoundPool Clubb1;
int clubb1Id;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.mrsclubb);
Clubb1 = new SoundPool(10, AudioManager.STREAM_MUSIC, 1);
clubb1Id = Clubb1.load(this, R.raw.clubb1,1);
Toolbar toolbar = (Toolbar)findViewById(R.id.toolbar);
mDrawerLayout = (DrawerLayout)findViewById(R.id.drawer);
mDrawerList = (ListView)findViewById(android.R.id.list);
mDrawerListItems = getResources().getStringArray(R.array.drawer_list);
mDrawerList.setAdapter(new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, mDrawerListItems));
mDrawerList.setOnItemClickListener(new AdapterView.OnItemClickListener()
{
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
switch(position) {
case 0:
Intent i = new Intent(MrsClubb.this, MrsClubb.class);
startActivity(i);
}
mDrawerLayout.closeDrawer(mDrawerList);
}
});
mDrawerToggle = new ActionBarDrawerToggle(this,
mDrawerLayout,
toolbar,
R.string.drawer_open,
R.string.drawer_close){
public void onDrawerClosed(View v){
super.onDrawerClosed(v);
invalidateOptionsMenu();
syncState();
}
public void onDrawerOpened(View v){
super.onDrawerOpened(v);
invalidateOptionsMenu();
syncState();
}
};
mDrawerLayout.setDrawerListener(mDrawerToggle);
setSupportActionBar(toolbar);
getSupportActionBar().setDisplayHomeAsUpEnabled(true);
getSupportActionBar().setHomeButtonEnabled(true);
mDrawerToggle.syncState();
}
#Override
protected void onPostCreate(Bundle savedInstanceState){
super.onPostCreate(savedInstanceState);
mDrawerToggle.syncState();
}
#Override
public void onConfigurationChanged(Configuration newConfig){
super.onConfigurationChanged(newConfig);
mDrawerToggle.onConfigurationChanged(newConfig);
}
#Override
public boolean onOptionsItemSelected(MenuItem item){
switch (item.getItemId()){
case android.R.id.home: {
if (mDrawerLayout.isDrawerOpen(mDrawerList)){
mDrawerLayout.closeDrawer(mDrawerList);
} else {
mDrawerLayout.openDrawer(mDrawerList);
}
return true;
}
default: return super.onOptionsItemSelected(item);
}
} public void playSound1(View view) {Clubb1.play(clubb1Id, 1, 1, 1, 0, 1);}
}
This is the manifest:
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".MrsClubb"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MRSCLUBB" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
</application>
Here is the LogCat:
-30 21:58:33.984 1971-1971/com.jonatboard.jonat.htssoundboard D/AndroidRuntime﹕ Shutting
down VM
--------- beginning of crash
03-30 21:58:33.985 1971-1971/com.jonatboard.jonat.htssoundboard E/AndroidRuntime﹕
FATAL EXCEPTION: main
Process: com.jonatboard.jonat.htssoundboard, PID: 1971
java.lang.RuntimeException: Unable to start activity
ComponentInfo{com.jonatboard.jonat.htssoundboard/com.jonatboard.jonat.htssoundboard.MrsClu
bb}: java.lang.NullPointerException: Attempt to invoke virtual method 'void
android.widget.ListView.setAdapter(android.widget.ListAdapter)' on a null object reference
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2298)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
at android.app.ActivityThread.access$800(ActivityThread.java:144)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void
android.widget.ListView.setAdapter(android.widget.ListAdapter)' on a null object reference
at com.jonatboard.jonat.htssoundboard.MrsClubb.onCreate(MrsClubb.java:49)
at android.app.Activity.performCreate(Activity.java:5933)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
at android.app.ActivityThread.access$800(ActivityThread.java:144)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
If you need any more code let me know, your help is much appreciated.

Your problem is with referring to the ListView in the DrawerLayout incorrectly in the MrsClubb activity. Here is an example of how you should be using and referring to the ListView.
<android.support.v4.widget.DrawerLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="#+id/drawer_layout"
android:layout_width="match_parent"
android:layout_height="match_parent">
<FrameLayout
android:id="#+id/content"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
<ListView
android:id="#+id/drawer"
android:layout_width="240dp"
android:layout_height="match_parent"
android:layout_gravity="start"
android:background="#111"
android:choiceMode="singleChoice"
android:divider="#android:color/transparent"
android:dividerHeight="0dp"/>
</android.support.v4.widget.DrawerLayout>
Now you can refer to the ListView in the DrawerLayout as:
ListView lv = (ListView) findViewByid(R.id.drawer);
Using Android provided IDs can sometimes get tricky and I believe this is where you have gone wrong.

Here is your problem:
java.lang.NullPointerException: Attempt to invoke virtual method 'void
android.widget.ListView.setAdapter(android.widget.ListAdapter)' on a null object reference
Looks like your listView is null, check to make sure you are declaring and finding it correctly in your activity.

Android start activity with button?

i keep getting a null pointer exception
I have a problem about starting a new activity via using button.
I already checked the previous questions related to mine problem, one of them is almost same but solutions didn't work out for me. So here is my problem.
whenever i start the app it crashes.
i have a main class called MainActivity and new Activity called login
Main class
public class MainActivity extends Activity {
Intent myIntent = new Intent(MainActivity.this, login.class);
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button loginButton = (Button) findViewById(R.id.button_login);
loginButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
startActivity(myIntent);
}
});
}
#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(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();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
return rootView;
}
}
}
logcat
02-18 10:27:42.520 1098-1098/com.example.app E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.example.app, PID: 1098
java.lang.RuntimeException: Unable to start activity ComponentInfo{com.example.app/com.example.app.MainActivity}: java.lang.NullPointerException
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
at android.app.ActivityThread.access$800(ActivityThread.java:135)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:136)
at android.app.ActivityThread.main(ActivityThread.java:5017)
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:779)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.NullPointerException
at com.example.app.MainActivity.onCreate(MainActivity.java:30)
at android.app.Activity.performCreate(Activity.java:5231)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
            at android.app.ActivityThread.access$800(ActivityThread.java:135)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
            at android.os.Handler.dispatchMessage(Handler.java:102)
            at android.os.Looper.loop(Looper.java:136)
            at android.app.ActivityThread.main(ActivityThread.java:5017)
            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:779)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
            at dalvik.system.NativeStart.main(Native Method)
thanks in advance!!!
EDIT---> MANIFEST
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.app" >
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.example.app.MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.example.app.login"
android:label="#string/title_activity_login" >
<intent-filter>
<action android:name="android.intent.action.LOGIN" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
</application>
</manifest>
MainActivity Layout
<RelativeLayout 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:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin"
tools:context="com.example.app.MainActivity">
//login Button
<Button
android:layout_width="120dp"
android:layout_height="wrap_content"
android:text="Login"
android:id="#+id/button_login"
android:layout_marginBottom="160dp"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginLeft="23dp" />
//high score button
<Button
android:layout_width="120dp"
android:layout_height="wrap_content"
android:text="high score"
android:id="#+id/highScore"
android:layout_alignTop="#+id/button_login"
android:layout_toRightOf="#+id/button_login"
android:layout_marginLeft="45dp" />
//play Button
<Button
android:layout_width="150dp"
android:layout_height="wrap_content"
android:text="Play"
android:id="#+id/Play"
android:layout_above="#+id/button_login"
android:layout_centerHorizontal="true"
android:layout_marginBottom="55dp" />
</RelativeLayout>
Edited corrections with imports
package com.example.app;
import android.app.Activity;
import android.content.Intent;
import android.support.v7.app.ActionBarActivity;
import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ImageButton;
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button loginButton = (Button) findViewById(R.id.button_login);
// if (savedInstanceState == null) {
// getSupportFragmentManager().beginTransaction()
// .add(R.id.container, new PlaceholderFragment())
// .commit();
// }
loginButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Intent myIntent = new Intent(MainActivity.this, login.class);
startActivity(myIntent);
}
});
}
#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(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();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* A placeholder fragment containing a simple view.
*/
public static class PlaceholderFragment extends Fragment {
public PlaceholderFragment() {
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
return rootView;
}
}
}

Move this inside the onCreate method :
Intent myIntent = new Intent(MainActivity.this, login.class);
By using that line outside the method, you are referring to the instance of MainActivity before it is fully created.
Since it looks like you are only using that intent once, you could even move that line inside the onClick method of the loginButton's OnClickListener, as suggested by InnocentKiller.

Remove this line from top of your screen
Intent myIntent = new Intent(MainActivity.this, login.class);
and put under the button click event. So basically your code will something like this for MainActivity.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button loginButton = (Button) findViewById(R.id.button_login);
loginButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Intent myIntent = new Intent(MainActivity.this, login.class);
startActivity(myIntent);
}
});
............
...........
}

Do you have the Login activity declared on your manifest as an activity
<activity
android:name="com.examlpe.app.loginActivity"/>

You need an Intent!
try:
loginButton.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Intent myIntent = new Intent(MainActivity.this, Login.class);
startActivity(myIntent);
}
});
Your login class should also be named "Login" to serve the name convention
And you need to add the new Login.class to your Manifest like
<activity
android:name="com.example.yourapp.Login"
android:label="#string/app_name"
<intent-filter>
<action android:name="android.intent.action.VIEW" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity