How to create a fun game Android App like Geiger tilt counter based on Accelerometer sensor?

Geiger Tilt counter Android App Game

In this video it shows a simple code to create a Geiger Counter kind of game based on the tilt of the phone. It uses Accelerometer sensor to detect the tilt of the phone.

I hope you like this video. For any questions, suggestions or appreciation please contact us at: https://programmerworld.co/contact/ or email at: programmerworld1990@gmail.com

Code:

package com.programmerworld.geigercounter;

// How to create a fun game Android App like Geiger counter playing with Friends?

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.os.Handler;
import android.widget.Toast;

import androidx.appcompat.app.AppCompatActivity;

public class MainActivity extends AppCompatActivity implements SensorEventListener {

    private SensorManager sensorManager;
    private Sensor accelerometer;
    private float tiltAngle;
    private MediaPlayer mediaPlayer;
    private AnalogMeterView meterView;
    private Handler soundHandler = new Handler();
    private boolean isPlayingSound = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        meterView = new AnalogMeterView(this);
        setContentView(meterView);

        sensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
        if (sensorManager != null) {
            accelerometer = sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
        }

        mediaPlayer = MediaPlayer.create(this, R.raw.geiger_click); // Place geiger_click.mp3 in res/raw

        if (accelerometer == null) {
            Toast.makeText(this, "Accelerometer not available", Toast.LENGTH_LONG).show();
            finish();
        }
    }

    @Override
    protected void onResume() {
        super.onResume();
        if (accelerometer != null) {
            sensorManager.registerListener(this, accelerometer, SensorManager.SENSOR_DELAY_UI);
        }
    }

    @Override
    protected void onPause() {
        super.onPause();
        if (accelerometer != null) {
            sensorManager.unregisterListener(this);
        }
        stopSound();
    }

    @Override
    public void onSensorChanged(SensorEvent event) {
        if (event.sensor.getType() == Sensor.TYPE_ACCELEROMETER) {
            float x = event.values[0];
            float y = event.values[1];
            tiltAngle = (float) Math.toDegrees(Math.atan2(x, y));
            meterView.updateAngle(tiltAngle);
            playSoundBasedOnTilt();
        }
    }

    @Override
    public void onAccuracyChanged(Sensor sensor, int accuracy) {
        // Not needed
    }

    private void playSoundBasedOnTilt() {
        if (!isPlayingSound) {
            isPlayingSound = true;
            soundHandler.postDelayed(() -> {
                if (mediaPlayer != null) {
                    mediaPlayer.start();
                }
                isPlayingSound = false;
            }, Math.max(50, 300 - (int) Math.abs(tiltAngle) * 10));
        }
    }

    private void stopSound() {
        if (mediaPlayer != null) {
            mediaPlayer.stop();
            mediaPlayer.release();
            mediaPlayer = null;
        }
    }

    class AnalogMeterView extends androidx.appcompat.widget.AppCompatImageView {
        private Paint paint;
        private float angle = 0;

        public AnalogMeterView(Context context) {
            super(context);
            paint = new Paint();
            paint.setAntiAlias(true);
            paint.setStyle(Paint.Style.STROKE);
            paint.setStrokeWidth(8);
            paint.setColor(Color.YELLOW);
        }

        public void updateAngle(float angle) {
            this.angle = angle;
            invalidate();
        }

        @Override
        protected void onDraw(Canvas canvas) {
            super.onDraw(canvas);

            int width = getWidth();
            int height = getHeight();

            // Draw meter arc
            paint.setColor(Color.YELLOW);
            paint.setStyle(Paint.Style.STROKE);
            canvas.drawArc(50, 50, width - 50, height - 50, 180, 180, false, paint);

            // Draw needle
            paint.setColor(Color.RED);
            paint.setStrokeWidth(12);
            float centerX = width / 2;
            float centerY = height / 2 + (height - 100) / 4;
            float needleLength = (width - 100) / 2;
            double radians = Math.toRadians(angle);
            float needleX = (float) (centerX + needleLength * Math.cos(Math.PI + radians));
            float needleY = (float) (centerY + needleLength * Math.sin(Math.PI + radians));
            canvas.drawLine(centerX, centerY, needleX, needleY, paint);
        }
    }
}

Screenshots: