Exception Attempt to invoke virtual method 'void android.support.v7.app.ActionBar.setDisplayHomeAsUpEnabled(boolean)' on a null object reference

[Shahjahan786]

Process: com.my.app, PID: 2142 java.lang.RuntimeException: Unable to start activity ComponentInfo{com.my.app/droidninja.filepicker.FilePickerActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.v7.app.ActionBar.setDisplayHomeAsUpEnabled(boolean)' on a null object reference at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2724) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2789) at android.app.ActivityThread.-wrap12(ActivityThread.java) at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1527) at android.os.Handler.dispatchMessage(Handler.java:110) at android.os.Looper.loop(Looper.java:203) at android.app.ActivityThread.main(ActivityThread.java:6251) at java.lang.reflect.Method.invoke(Native Method) at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1073) at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:934) Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.support.v7.app.ActionBar.setDisplayHomeAsUpEnabled(boolean)' on a null object reference at droidninja.filepicker.BaseFilePickerActivity.onCreate(BaseFilePickerActivity.java:27) at droidninja.filepicker.FilePickerActivity.onCreate(FilePickerActivity.java:26) at android.app.Activity.performCreate(Activity.java:6687) at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118) at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2677) at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2789)  at android.app.ActivityThread.-wrap12(ActivityThread.java)  at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1527)  at android.os.Handler.dispatchMessage(Handler.java:110)  at android.os.Looper.loop(Looper.java:203)  at android.app.ActivityThread.main(ActivityThread.java:6251)  at java.lang.reflect.Method.invoke(Native Method)  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1073)  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:934) 

[zeevy]

You should try

getSupportActionBar().setDisplayHomeAsUpEnabled(true);

[Kenworld]

Am getting same error after trying to add a custom dialog it started complaining about getSupportActionBar().setDisplayHomeAsUpEnabled(true); but was working fine

[Murtaza22]

Am getting same error after trying to add a custom dialog it started complaining about getSupportActionBar().setDisplayHomeAsUpEnabled(true); but was working fine

It is not working for me

[itzpkyadav]

You should try this one. I think it will work.

    Toolbar toolbar = findViewById(R.id.toolbar1);
    setSupportActionBar(toolbar);
    mDrawerLayout = findViewById(R.id.drawer_layout);
    mDrawerLayout = findViewById(R.id.drawer_layout);
    mDrawerLayout.setDrawerShadow(R.drawable.rectagle_with_black_outer,
            GravityCompat.START);
    getSupportActionBar().setDisplayHomeAsUpEnabled(true);
    getSupportActionBar().setHomeButtonEnabled(true);

    mDrawerToggle = new ActionBarDrawerToggle(this, mDrawerLayout,
            toolbar, R.string.navigation_drawer_close,
            R.string.navigation_drawer_close) {
        public void onDrawerClosed(View view) {
            invalidateOptionsMenu();
        }

        public void onDrawerOpened(View drawerView) {
            invalidateOptionsMenu();
        }
    };