MainActivity.java

package com.example.uicustomviews;

import android.support.v7.app.ActionBar;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.Window;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        ActionBar actionbar = getSupportActionBar();
        if (actionbar != null) {
            actionbar.hide();
        }
    }
}