Remove preset wallpaper within Launcher

package org.indin.blisslaunchero.features.launcher;

import static android.view.View.GONE;

import static android.view.View.VISIBLE;

import static cyanogenmod.providers.WeatherContract.WeatherColumns.TempUnit.CELSIUS;

import static cyanogenmod.providers.WeatherContract.WeatherColumns.TempUnit.FAHRENHEIT;

import static cyanogenmod.providers.WeatherContract.WeatherColumns.WindSpeedUnit.KPH;

import static cyanogenmod.providers.WeatherContract.WeatherColumns.WindSpeedUnit.MPH;

import android.animation.Animator;

import android.animation.AnimatorListenerAdapter;

import android.animation.LayoutTransition;

import android.app.Activity;

import android.app.WallpaperManager;

import android.app.usage.UsageStats;

import android.content.BroadcastReceiver;

import android.content.Context;

import android.content.Intent;

import android.content.IntentFilter;

import android.graphics.Bitmap;

import android.graphics.BitmapFactory;

import android.graphics.Rect;

import android.graphics.drawable.Drawable;

import android.net.Uri;

import android.support.v7.widget.RecyclerView;

import android.text.Editable;

import android.text.TextWatcher;

import android.util.DisplayMetrics;

import android.util.Log;

import android.util.TypedValue;

import android.view.DragEvent;

import android.widget.Toast;

import com.crashlytics.android.Crashlytics;

import com.google.firebase.analytics.FirebaseAnalytics;

import com.jakewharton.rxbinding2.widget.RxTextView;

import org.greenrobot.eventbus.EventBus;

import me.relex.circleindicator.CircleIndicator;

import uk.co.chrisjenx.calligraphy.CalligraphyContextWrapper;

import static android.view.View.GONE;

import static android.view.View.VISIBLE;

import static cyanogenmod.providers.WeatherContract.WeatherColumns.TempUnit.CELSIUS;

import static cyanogenmod.providers.WeatherContract.WeatherColumns.TempUnit.FAHRENHEIT;

import static cyanogenmod.providers.WeatherContract.WeatherColumns.WindSpeedUnit.KPH;

import static cyanogenmod.providers.WeatherContract.WeatherColumns.WindSpeedUnit.MPH;

public class LauncherActivity extends AppCompatActivity implements

        AutoCompleteAdapter.OnSuggestionClickListener {

    public void showApps() {

        allAppsDisplayed = true;

        showIconPackWallpaperFirstTime();

        mProgressBar.setVisibility(GONE);

        createUI();

        isUiDone = true;

        return false;

    }

    private void showIconPackWallpaperFirstTime() {

        if (Preferences.isFirstTime(this)) {

            Bitmap bmap2 = BitmapFactory.decodeStream(

                    getResources().openRawResource(+R.drawable.graphics_1));

            DisplayMetrics metrics = new DisplayMetrics();

            getWindowManager().getDefaultDisplay().getMetrics(metrics);

            int height = metrics.heightPixels;

            int width = metrics.widthPixels;

            Bitmap bitmap = Bitmap.createScaledBitmap(bmap2, width, height, true);

            WallpaperManager wallpaperManager = WallpaperManager.getInstance(this);

            try {

                wallpaperManager.setResource(+R.drawable.graphics_1);

                wallpaperManager.setBitmap(bitmap);

                Preferences.setFirstTimeDone(this);

            } catch (IOException e) {

                e.printStackTrace();

            }

        }

    }

    /**

     * Adds a listener to the folder title.

     * When clicked, the TextView transforms into an EditText.