LicenseActivity.java

package com.mercandalli.android.apps.files.settings;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.v7.app.ActionBar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.Toolbar;
import android.view.MenuItem;
import android.webkit.WebView;

import com.mercandalli.android.apps.files.R;
import com.mercandalli.android.library.base.precondition.Preconditions;

public class LicenseActivity extends AppCompatActivity {

    private static final String URL = "file:///android_asset/licenses.html";

    public static void start(@NonNull final Context context) {
        Preconditions.checkNotNull(context);
        final Intent intent = new Intent(context, LicenseActivity.class);
        if (!(context instanceof Activity)) {
            intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
        }
        context.startActivity(intent);
    }

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

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        if (item.getItemId() == android.R.id.home) {
            finish();
            return true;
        }
        return super.onOptionsItemSelected(item);
    }

    private void initViews() {
        ((WebView) findViewById(R.id.activity_license_web_view)).loadUrl(URL);
    }

    private void initToolbar() {
        final Toolbar toolbar = (Toolbar) findViewById(R.id.activity_license_toolbar);
        setSupportActionBar(toolbar);
        final ActionBar actionBar = getSupportActionBar();
        if (actionBar != null) {
            actionBar.setDisplayHomeAsUpEnabled(true);
        }
    }
}