MainActivity.java

package dev.androidgame.gameloop;

import android.os.Bundle;
import android.app.Activity;
import android.content.Context;
import android.content.pm.ActivityInfo;
import android.graphics.Canvas;
import android.graphics.Color;
import android.graphics.Paint;
import android.util.Log;
import android.view.MotionEvent;
import android.view.SurfaceHolder;
import android.view.SurfaceView;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.view.View.OnTouchListener;

public class MainActivity extends Activity {
	
	GameView gameView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);
	    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN);
		/*inisialisasi gameView dan menetapkannya sebagai view dari Activity*/
        gameView = new GameView(this);
        setContentView(gameView);
        setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_PORTRAIT);
		//setRequestedOrientation(ActivityInfo.SCREEN_ORIENTATION_LANDSCAPE);
    }
    
    @Override
    protected void onResume() {
        super.onResume(); 
        gameView.resume();
    }
 
    @Override
    protected void onPause() {
        super.onPause();
        gameView.pause();
    }

    class GameView extends SurfaceView implements OnTouchListener, Runnable{
    	
    	private Context context;
    	private Thread	thread;
    	private SurfaceHolder surfaceHolder;
    	private volatile boolean running;	
    	
    	private final static int	MAX_FPS 		= 60;
    	private final static int	MAX_FRAME_SKIPS = 5;
    	private final static int	FRAME_PERIOD 	= 1000 / MAX_FPS;		
    	
    	//sebuah objek canvas dan paint
        Canvas canvas;
        Paint paint	= new Paint(Paint.ANTI_ALIAS_FLAG);
        
        float sx,sy;
        int pembagi	= 100;
        boolean initialized	= false;

		public GameView(Context context) {
			super(context);
			this.context	= context;
			surfaceHolder 	= getHolder();
	        setOnTouchListener(this);
		}
		
		public void resume() {
			thread	= new Thread(this);
			running	= true;
			thread.start();			
		}
		
		public void pause(){
			running = false;
	        try {
	            thread.join();
	        } catch (InterruptedException e) {
	            Log.e("Error:", "joining thread");
	        }
		}
		
		public void exit(){
			running	= false;
			System.exit(0);
		}
		
		private void initialize(Canvas canvas){
			if(!initialized){
				sx	= canvas.getWidth()/(float)pembagi;
				sy	= canvas.getHeight()/(float)pembagi;
				
				initialized	= true;
			}
		}
		
		private void update() {
			//   
		}	

		private void draw() {
			if (surfaceHolder.getSurface().isValid()) {
				canvas = surfaceHolder.lockCanvas();
				initialize(canvas);
				canvas.drawColor(Color.WHITE);
				//gambar disini untuk ditampilkan ke screen	
				for(int i=0;i<pembagi;i++){
					paint.setColor(Color.rgb(52, 152, 219));
					canvas.drawLine(0, sy*i, canvas.getWidth(), sy*i, paint);
					paint.setColor(Color.rgb(231, 76, 60));
					canvas.drawLine(sx*i, 0, sx*i, canvas.getHeight(), paint);
				}
	            surfaceHolder.unlockCanvasAndPost(canvas);
			}
			
		}

		@Override
		public void run() {
			long beginTime;
			long timeDiff;		
			int sleepTime		= 0;
			int framesSkipped;	
			//GAMELOOP
			while (running) {
				try {
					beginTime = System.currentTimeMillis();
					framesSkipped = 0;
					synchronized(surfaceHolder){					
						update();
						draw();					
					}
					timeDiff = System.currentTimeMillis() - beginTime;
					sleepTime = (int)(FRAME_PERIOD - timeDiff);
					if (sleepTime > 0) {
						try {
							thread.sleep(sleepTime);	
						} catch (InterruptedException e) {}
					}				
					while (sleepTime < 0 && framesSkipped < MAX_FRAME_SKIPS) {
						update();
						sleepTime += FRAME_PERIOD;	
						framesSkipped++;
					}			
				}finally{}
			}			
		}

		@Override
		public boolean onTouch(View view, MotionEvent event) {
			float x	= event.getX();
			float y	= event.getY(); 
			switch(event.getAction()& MotionEvent.ACTION_MASK) {		 
	        case MotionEvent.ACTION_DOWN:
	        	// 	
	            break;
	        case MotionEvent.ACTION_UP:
	        	//
	            break;
	        case MotionEvent.ACTION_MOVE:
	        	//
	            break;
			}		
			return true;
		}    	
    }    
}