Getting Null Pointer Exception While Setting The Title To Action Bar

Error:Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void android.app.ActionBar.setTitle(java.lang.CharSequence)' on a null object reference tried

Solution 1:

Some premisses:

• Check if you had declared import android.support.v7.app.AppCompatActivityand your activity is extended it.
• Check if you declared WINDOWS_FEATURE: requestWindowFeature(Window.FEATURE_ACTION_BAR); or in your style: <item name="android:windowActionBar">true</item>

regards,

Solution 2:

Its the problem in the style sheet That says

"<style name="AppTheme.NoActionBar">"

Define some theme then you get rid of null pointer exception

Solution 3:

If you are using an INTENT with AppCompatActivity, you need to access to the same relevant thread:

YourClass mContext;
mContext.runOnUiThread(newRunnable() {
    @Overridepublicvoidrun() {
        mContext.getSupportActionBar().hide();
    }
});

YourClass is the one extending AppCompActivity:

publicclassYourClassextendsAppCompatActivity {
}