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Apps Need help solving a java.lang.NullPointerException

S

Schmidty850

Newbie
I'm going to preface this with I have searched everywhere to try to fix this and have searched the forums here too. I really just need some help to get it fixed.

Here's my code:

HTML: 
package com.app.Studio17.learntocode;

import android.content.Intent;
import android.content.res.Configuration;
import android.content.res.TypedArray;
import android.os.Bundle;
import android.support.v4.app.ActionBarDrawerToggle;
import android.support.v4.widget.DrawerLayout;
import android.support.v7.app.ActionBarActivity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.RelativeLayout;
import java.util.ArrayList;

public class BaseActivity extends ActionBarActivity {
    private DrawerLayout mDrawerLayout;
    private ListView mDrawerList;
    private ActionBarDrawerToggle mDrawerToggle;
    protected RelativeLayout _completeLayout, _activityLayout;
    // nav drawer title
    private CharSequence mDrawerTitle;

    // used to store app title
    private CharSequence mTitle;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.drawer);

        // // on first time display view for first nav item
        if (savedInstanceState == null) {
        displayView(0);
        }

        //initializations
        mTitle = mDrawerTitle = getTitle();
        mDrawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);
        mDrawerList = (ListView) findViewById(R.id.left_drawer);

        // load titles and icons from strings.xml
        String[] navMenuTitles = getResources().getStringArray(R.array.nav_drawer_items);
        TypedArray navMenuIcons = getResources().obtainTypedArray(R.array.nav_drawer_icons);
        ArrayList<NavDrawerItem> navDrawerItems = new ArrayList<NavDrawerItem>();

        mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout,
                R.drawable.ic_drawer, // nav menu toggle icon
                R.string.drawer_open, // nav drawer open - description for
                // accessibility
                R.string.drawer_close // nav drawer close - description for
                // accessibility
        ) {
            public void onDrawerClosed(View view) {
                super.onDrawerClosed(view);
                getSupportActionBar().setTitle(mTitle);
                invalidateOptionsMenu();
                // calling onPrepareOptionsMenu() to show action bar icons
            }

            public void onDrawerOpened(View drawerView) {
                super.onDrawerOpened(drawerView);
                getSupportActionBar().setTitle(mDrawerTitle);
                invalidateOptionsMenu();
                // calling onPrepareOptionsMenu() to hide action bar icons
            }
        };

        // adding nav drawer items
        if(navMenuIcons ==null){
            for(int i=0;i< navMenuTitles.length;i++){
                navDrawerItems.add(new NavDrawerItem(navMenuTitles[i]));
            }
        }else{
            for(int i=0;i< navMenuTitles.length;i++){
                navDrawerItems.add(new NavDrawerItem(navMenuTitles[i],
                        navMenuIcons.getResourceId(i, -1)));
            }
        }

        // setting the nav drawer list adapter
        NavDrawerListAdapter adapter = new NavDrawerListAdapter(getApplicationContext(),
                navDrawerItems);
        mDrawerList.setAdapter(adapter);


        mDrawerList.setOnItemClickListener(new DrawerItemClickListener());


        // enabling action bar app icon and behaving it as toggle button
        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
        getSupportActionBar().setHomeButtonEnabled(true);
        // getSupportActionBar().setIcon(R.drawable.ic_drawer);

        mDrawerLayout.setDrawerListener(mDrawerToggle);
    }

    private class DrawerItemClickListener implements ListView.OnItemClickListener {
        @Override
        public void onItemClick(AdapterView parent, View view, int position,long id) {
            // display view for selected nav drawer item
            displayView(position);
        }
    }

    /***
     * Called when invalidateOptionsMenu() is triggered
     */
    @Override
    public boolean onPrepareOptionsMenu(Menu menu) {
        // if nav drawer is opened, hide the action items
        boolean drawerOpen = mDrawerLayout.isDrawerOpen(mDrawerList);
        menu.findItem(R.id.action_settings).setVisible(!drawerOpen);
        return super.onPrepareOptionsMenu(menu);
    }

    /**
     * Diplaying fragment view for selected nav drawer list item
     * */
    private void displayView(int position) {
        // update the main content by replacing fragments
        switch (position) {
            case 0:
                Intent intent = new Intent(this, Home.class);
                startActivity(intent);
                finish();
                break;
            case 1:
                Intent intent1 = new Intent(this, TSquare.class);
                startActivity(intent1);
                finish();
                break;
            case 2:
                Intent intent2 = new Intent(this, Buzzport.class);
                startActivity(intent2);
                finish();
                break;
            case 3:
                Intent intent3 = new Intent(this, Bus.class);
                startActivity(intent3);
                finish();
                break;
            case 4:
                Intent intent4 = new Intent(this, sting.class);
                startActivity(intent4);
                finish();
                break;
            default:
                break;
        }

        // update selected item and title, then close the drawer
        mDrawerList.setItemChecked(position, true);
        mDrawerList.setSelection(position);
        mDrawerLayout.closeDrawer(mDrawerList);
    }

    @Override
    public void setTitle(CharSequence title) {
        mTitle = title;
        getSupportActionBar().setTitle(mTitle);
    }

    @Override
    protected void onPostCreate(Bundle savedInstanceState) {
        super.onPostCreate(savedInstanceState);
        // Sync the toggle state after onRestoreInstanceState has occurred.
        mDrawerToggle.syncState();
    }

    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        // Pass any configuration change to the drawer toggles
        mDrawerToggle.onConfigurationChanged(newConfig);
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        if (mDrawerToggle.onOptionsItemSelected(item)) {
            return true;
        }
        if (item.getItemId() == android.R.id.home) {
            if (mDrawerLayout.isDrawerOpen(mDrawerList)) {
                mDrawerLayout.closeDrawer(mDrawerList);
            } else {
                mDrawerLayout.openDrawer(mDrawerList);
            }
        }

        return super.onOptionsItemSelected(item);
    }
}

And here's my logcat:

HTML: 
07-22 21:58:11.823    1685-1685/com.app.Studio17.learntocode E/AndroidRuntime&#65109; FATAL EXCEPTION: main
    java.lang.RuntimeException: Unable to start activity ComponentInfo{com.app.Studio17.learntocode/com.app.Studio17.learntocode.Home}: java.lang.NullPointerException
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2059)
            at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
            at android.app.ActivityThread.access$600(ActivityThread.java:130)
            at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
            at android.os.Handler.dispatchMessage(Handler.java:99)
            at android.os.Looper.loop(Looper.java:137)
            at android.app.ActivityThread.main(ActivityThread.java:4745)
            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:786)
            at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
            at dalvik.system.NativeStart.main(Native Method)
     Caused by: java.lang.NullPointerException
            at com.app.Studio17.learntocode.BaseActivity.displayView(BaseActivity.java:155)
            at com.app.Studio17.learntocode.BaseActivity.onCreate(BaseActivity.java:36)
            at com.app.Studio17.learntocode.Home.onCreate(Home.java:9)
            at android.app.Activity.performCreate(Activity.java:5008)
            at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1079)
            at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2023)
************at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
************at android.app.ActivityThread.access$600(ActivityThread.java:130)
************at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
************at android.os.Handler.dispatchMessage(Handler.java:99)
************at android.os.Looper.loop(Looper.java:137)
************at android.app.ActivityThread.main(ActivityThread.java:4745)
************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:786)
************at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
************at dalvik.system.NativeStart.main(Native Method)

With Home.java being:

HTML: 
package com.app.Studio17.learntocode;

import android.os.Bundle;

public class Home extends BaseActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_home);
    }

}
 
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