I'm programming a pacman, the game is drawed in a SurfaceView, but I have problem to pause it and getting the atributes while it's running (no when I set them)
For example, I set a Semaphore that should be referenced in the Activity and in the Game view, and it is set it correct, but when the thread of the game view is running, and try to release the semaphore it indicates a NullPointerException.
On the other hand, when I try to pause the game, the game used to keep running in the background, and now when I resume it don't run
I'm sure the problem is with the references in memory, when I set and atribute as static i can access from both (view and surfaceview are the same object). I don't know why this happen.
Brief resume: An AppCompatActivity (which is PlayActivity) has a SurfaView (which is GameView), and this SurfaceView has the GameManager(which has all the things of the pacman in a moment). The references when the AppCompatActivity try to get something of the SurfaceView (for example the gameManager) are lost in execution.
Here the code
PlayActivity
public class PlayActivity extends AppCompatActivity {
private TextView playerNickname;
private TextView scoreTv;
private TextView maxScore;
private SurfaceView gameSurfaceView;
private GameView gameView;
private static Semaphore CHANGE_LIFES_MUTEX=new Semaphore(0,true);
private static Semaphore CHANGE_SCORE_MUTEX=new Semaphore(0,true);
private static Semaphore CHANGE_DIRECTION_MUTEX=new Semaphore(0,true);
private Thread changeScoreThread, changeDirectionThread;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//Modified code
setContentView(R.layout.activity_game);
//we get text view that we will use
playerNickname=(TextView) this.findViewById(R.id.tv_player);
scoreTv=(TextView) this.findViewById(R.id.tv_current_score);
maxScore=(TextView) this.findViewById(R.id.tv_current_max_score);
gameSurfaceView= (GameView) this.findViewById(R.id.game_view);
//set text view initial values
playerNickname.setText(getIntent().getExtras().getString("playerNickname"));
scoreTv.setText("0");
maxScore.setText("To modify");
this.gameView=new GameView(gameSurfaceView.getContext());
this.gameView.setSemaphores(CHANGE_SCORE_MUTEX,CHANGE_DIRECTION_MUTEX);
this.gameSurfaceView.getHolder().addCallback(this.gameView);
}
protected void onResume(){
super.onResume();
this.gameView.resume();
this.initChangerThreads();
}
public void updateScoreTv(int score){
this.scoreTv.setText(""+score);
}
protected void onPause(){
super.onPause();
this.gameView.pause();
//in order to stop the threads
CHANGE_SCORE_MUTEX.release();
CHANGE_DIRECTION_MUTEX.release();
}
public void onLose(int score){
//We try to save the score, if there is a previous register we write only if this score
//is better that the one before
DBManager manager;
long raw;
Score scoreToSave;
manager=new DBManager(this);
scoreToSave=new Score(this.playerNickname.toString(), score);
if(manager.saveScore(scoreToSave)==-1){
//if i couldn't save the score
if(manager.updateScore(scoreToSave)!=-1){
//if my new score is better than the one previous
}else{
//if my new score is worse or equal than the one previous
}
}
}
private void initChangerThreads() {
this.changeScoreThread = new Thread(new Runnable() {
public void run() {
while (gameView.isDrawing()) {
//Log.i("Score ",""+gameManager.getScore());
try {
CHANGE_SCORE_MUTEX.acquire();
runOnUiThread(new Runnable() {
#Override
public void run() {
updateScoreTv(gameView.getGameManager().getScore());
}
});
}catch (Exception e){}
}
Log.i("Score Thread","ended");
}
});
this.changeScoreThread.start();
}
}
GameView
public class GameView extends SurfaceView implements Runnable, SurfaceHolder.Callback, GestureDetector.OnGestureListener {
private static final float SWIPE_THRESHOLD = 2;
private static final float SWIPE_VELOCITY = 2;
private static boolean CAN_DRAW = false;
private boolean GHOST_INICIALIZED=false;
private GestureDetector gestureDetector;
private GameManager gameManager;
private Thread thread; //game thread
private SurfaceHolder holder;
private int blockSize; // Ancho de la pantalla, ancho del bloque
private static int movementFluencyLevel=8; //this movement should be a multiple of the blocksize and multiple of 4, if note the pacman will pass walls
private int totalFrame = 4; // Cantidad total de animation frames por direccion
private int currentArrowFrame = 0; // animation frame de arrow actual
private long frameTicker; // tiempo desde que el ultimo frame fue dibujado
//----------------------------------------------------------------------------------------------
//Constructors
public GameView(Context context) {
super(context);
this.constructorHelper(context);
}
public GameView(Context context, AttributeSet attrs) {
super(context, attrs);
this.constructorHelper(context);
}
public GameView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
this.constructorHelper(context);
}
private void constructorHelper(Context context) {
this.gestureDetector = new GestureDetector(this);
setFocusable(true);
this.holder = getHolder();
this.holder.addCallback(this);
this.frameTicker = (long) (1000.0f / totalFrame);
this.gameManager=new GameManager();
int screenWidth=getResources().getDisplayMetrics().widthPixels;
this.blockSize = ((((screenWidth/this.gameManager.getGameMap().getMapWidth())/movementFluencyLevel)*movementFluencyLevel)/4)*4;
this.holder.setFixedSize(blockSize*this.gameManager.getGameMap().getMapWidth(),blockSize*this.gameManager.getGameMap().getMapHeight());
this.gameManager.getGameMap().loadBonusBitmaps(this.getBlockSize(),this.getResources(),this.getContext().getPackageName());
this.gameManager.setPacman(new Pacman("pacman","",this.movementFluencyLevel,this.gameManager.getGameMap().getPacmanSpawnPosition(),this.blockSize,this.getResources(),this.getContext().getPackageName()));
Ghost.loadCommonBitmaps(this.blockSize,this.getResources(),this.getContext().getPackageName());
}
//----------------------------------------------------------------------------------------------
//Getters and setters
public int getBlockSize() {
return blockSize;
}
public GameManager getGameManager() {
return gameManager;
}
public boolean isDrawing(){
return CAN_DRAW;
}
//----------------------------------------------------------------------------------------------
private synchronized void initGhost(){
if(!GHOST_INICIALIZED){
GHOST_INICIALIZED=true;
this.gameManager.initGhosts(this.blockSize,this.getResources(),this.getContext().getPackageName(),movementFluencyLevel);
}
}
#RequiresApi(api = Build.VERSION_CODES.N)
#Override
public void run() {
long gameTime;
Canvas canvas;
while (!holder.getSurface().isValid()) {
}
this.initGhost();
this.setFocusable(true);
while (CAN_DRAW) {
gameTime=System.currentTimeMillis();
if(gameTime > frameTicker + (totalFrame * 15)){
canvas = holder.lockCanvas();
if(canvas!=null){
if(this.updateFrame(gameTime,canvas)){
try {
Thread.sleep(3000);
}catch (Exception e){}
}
holder.unlockCanvasAndPost(canvas);
if(this.gameManager.checkWinLevel()){
CAN_DRAW=false;
this.gameManager.cancelThreads();
try {
Thread.sleep(2000);
} catch (InterruptedException e) {}
//animation
Log.i("Game","You win");
}else if(!this.gameManager.getPacman().hasLifes()){
//we lost
CAN_DRAW=false;
this.gameManager.cancelThreads();
//animation
Log.i("Game","You lose");
}
}
}
}
}
// Method to capture touchEvents
#Override
public boolean onTouchEvent(MotionEvent event) {
//To swipe
//https://www.youtube.com/watch?v=32rSs4tE-mc
this.gestureDetector.onTouchEvent(event);
super.onTouchEvent(event);
return true;
}
//Chequea si se deberia actualizar el frame actual basado en el
// tiempo que a transcurrido asi la animacion
//no se ve muy rapida y mala
#RequiresApi(api = Build.VERSION_CODES.N)
private boolean updateFrame(long gameTime, Canvas canvas) {
Pacman pacman;
Ghost[] ghosts;
boolean pacmanIsDeath;
pacman=this.gameManager.getPacman();
ghosts=this.gameManager.getGhosts();
// Si el tiempo suficiente a transcurrido, pasar al siguiente frame
frameTicker = gameTime;
canvas.drawColor(Color.BLACK);
this.gameManager.getGameMap().draw(canvas, Color.BLUE,this.blockSize,this.gameManager.getLevel());
this.gameManager.moveGhosts(canvas,this.blockSize);
pacmanIsDeath=pacman.move(this.gameManager,canvas);
if(!pacmanIsDeath){
// incrementar el frame
pacman.changeFrame();
for(int i=0; i<ghosts.length;i++){
ghosts[i].changeFrame();
}
currentArrowFrame++;
currentArrowFrame%=7;
}else{
pacman.setNextDirection(' ');
for(int i=0; i<ghosts.length;i++){
ghosts[i].respawn();
}
}
return pacmanIsDeath;
}
public int getScore(){
return this.getGameManager().getScore();
}
public void setSemaphores(Semaphore changeScoreSemaphore, Semaphore changeDirectionSemaphore){
this.gameManager.setChangeScoreSemaphore(changeScoreSemaphore);
this.gameManager.getPacman().setChangeDirectionSemaphore(changeDirectionSemaphore);
Log.i("Semaphore", "setted");
}
//----------------------------------------------------------------------------------------------
//Callback methods
#RequiresApi(api = Build.VERSION_CODES.N)
#Override
public void surfaceCreated(SurfaceHolder holder) {
CAN_DRAW = true;
this.thread= new Thread(this);
this.thread.start();
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
Log.i("Surface","destroyed");
}
//----------------------------------------------------------------------------------------------
public void resume() {
CAN_DRAW = true;
thread = new Thread(this);
thread.start();
}
public void pause() {
CAN_DRAW = false;
while (true) {
try {
thread.join();
} catch (InterruptedException e) {
// retry
}
break;
}
this.thread=null;
}
#Override
public boolean onDown(MotionEvent e) {
return false;
}
#Override
public void onShowPress(MotionEvent e) {
}
#Override
public boolean onSingleTapUp(MotionEvent e) {
return false;
}
#Override
public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) {
return false;
}
#Override
public void onLongPress(MotionEvent e) {
}
#Override
public boolean onFling(MotionEvent downEvent, MotionEvent moveEvent, float velocityX, float velocityY) {
//To swipe
//https://www.youtube.com/watch?v=32rSs4tE-mc
boolean result;
float diffX, diffY;
Pacman pacman;
Log.i("Fling", "detected");
result=false;
diffX = moveEvent.getX() - downEvent.getX();
diffY = moveEvent.getY() - downEvent.getY();
pacman=this.gameManager.getPacman();
if (Math.abs(diffY) > SWIPE_THRESHOLD && Math.abs(velocityY) > SWIPE_VELOCITY){
if (Math.abs(diffX) > Math.abs(diffY)) {
if (diffX > 0) {
//right
pacman.setNextDirection('r');
} else {
//left
pacman.setNextDirection('l');
}
}else{
if (diffY > 0) {
//down
pacman.setNextDirection('d');
} else {
//up
pacman.setNextDirection('u');
}
}
result=true;
}
return result;
}
}
GameManager
public class GameManager {
private static final int TOTAL_LEVELS=256;
private static int SCORE=0;
private GameMap gameMap;
private int level,bonusResetTime;//,score;
private CountDownScareGhosts scareCountDown;
private Pacman pacman;
private Ghost[] ghosts;
private boolean fruitHasBeenInTheLevel;
private static Semaphore CHANGE_SCORE_MUTEX;
public GameManager(){
this.fruitHasBeenInTheLevel=false;
//this.score=0;
this.gameMap=new GameMap();
this.gameMap.loadMap1();
this.level=1;
this.ghosts=new Ghost[4];
this.bonusResetTime = 5000;
this.scareCountDown=null;
}
public void setChangeScoreSemaphore(Semaphore changeScoreSemaphore) {
CHANGE_SCORE_MUTEX = changeScoreSemaphore;
//if(this.changeScoreSemaphore==null){
// Log.i("Change Score Semaphore","I'm null");
//}else{
// Log.i("Change Score Semaphore","I'm not null");
//}
}
public void addScore(int s){
//this.score+=s;
SCORE+=s;
CHANGE_SCORE_MUTEX.release();
/*if(this.changeScoreSemaphore==null){
Log.i("Change Score Semaphore","I'm null");
}else{
Log.i("Change Score Semaphore","I'm not null");
}*/
//this.changeScoreSemaphore.release();
}
public int getScore() {
return SCORE;
//return this.score;
}
public int getLevel() {
return this.level;
}
public GameMap getGameMap() {
return this.gameMap;
}
public Ghost[] getGhosts(){
return this.ghosts;
}
public Pacman getPacman(){
return this.pacman;
}
public void setPacman(Pacman pacman){
this.pacman=pacman;
}
public void eatPallet(int posXMap, int posYMap){
SCORE+=10;
CHANGE_SCORE_MUTEX.release();
//this.score+=10;
Log.i("Score GM", ""+SCORE);
//Log.i("Score GM", ""+this.score);
this.gameMap.getMap()[posYMap][posXMap]=0;
//this.changeScoreSemaphore.release();
//if(this.changeScoreSemaphore==null){
// Log.i("Change Score Semaphore","I'm null");
//}else{
// Log.i("Change Score Semaphore","I'm not null");
//}
}
public void eatBonus(int posXMap,int posYMap){
SCORE+=500;
CHANGE_SCORE_MUTEX.release();
//this.score+=500;
//Log.i("Score", Double.toString(this.score).substring(0,Double.toString(this.score).indexOf('.')));
this.gameMap.getMap()[posYMap][posXMap]=0;
//this.changeScoreSemaphore.release();
}
public void eatSuperPallet(int posXMap,int posYMap){
SCORE+=50;
CHANGE_SCORE_MUTEX.release();
//this.score+=50;
this.gameMap.getMap()[posYMap][posXMap]=0;
//Si hay un timer andando lo cancelo y ejecuto otro
if (this.scareCountDown != null){
this.scareCountDown.cancel();
}
this.scareCountDown = new CountDownScareGhosts(this.ghosts,this.gameMap.getMap());
this.scareCountDown.start();
//this.changeScoreSemaphore.release();
}
public void tryCreateBonus(){
//only if pacman has eaten 20 pallets we should allow the fruit appear
if(!this.fruitHasBeenInTheLevel && this.gameMap.getEatenPallets()>=20){
//to not allow the fruit be again in the level
this.fruitHasBeenInTheLevel=true;
new CountdownBonusThread(this.gameMap,this.bonusResetTime).start();
}
}
#RequiresApi(api = Build.VERSION_CODES.N)
public void moveGhosts(Canvas canvas,int blocksize) {
for (int i = 0; i < ghosts.length; i++) {
ghosts[i].move(this.gameMap.getMap(),this.pacman);
ghosts[i].draw(canvas);
}
}
public synchronized void initGhosts(int blocksize, Resources res, String packageName,int movementFluency) {
int[][]spawnPositions,cornersPositions, notUpDownPositions,defaultTargets;
defaultTargets=this.gameMap.getDefaultGhostTarget();
notUpDownPositions=this.gameMap.getNotUpDownDecisionPositions();
spawnPositions=this.gameMap.getGhostsSpawnPositions();
cornersPositions=this.gameMap.getGhostsScatterTarget();
//start position
// 5 blinky spawn [13, 11]
// 6 pinky spawn [15,11]
// 7 inky spawn [13,16]
// 8 clyde spawn [15,16]
this.ghosts=new Ghost[4];
ghosts[0] = new Ghost("blinky",spawnPositions[0], cornersPositions[0] ,new BehaviorChaseAgressive(notUpDownPositions,movementFluency,defaultTargets[0]),movementFluency,notUpDownPositions,'l',defaultTargets[0],blocksize,res,packageName);
ghosts[1] = new Ghost("pinky",spawnPositions[1],cornersPositions[1],new BehaviorChaseAmbush(notUpDownPositions,movementFluency,defaultTargets[1]),movementFluency,notUpDownPositions,'r',defaultTargets[1],blocksize,res,packageName);
ghosts[2] = new Ghost("inky",spawnPositions[2],cornersPositions[2],new BehaviorChasePatrol(notUpDownPositions,this.ghosts[0],movementFluency,defaultTargets[0]),movementFluency,notUpDownPositions,'l',defaultTargets[0],blocksize,res,packageName);
ghosts[3] = new Ghost("clyde",spawnPositions[3],cornersPositions[3],new BehaviorChaseRandom(notUpDownPositions,cornersPositions[3],movementFluency,defaultTargets[1]),movementFluency,notUpDownPositions,'r',defaultTargets[1],blocksize,res,packageName);
try{
Thread.sleep(200);
}catch(Exception e){}
for (int i=0;i<ghosts.length;i++){
ghosts[i].onLevelStart(1);
}
}
public boolean checkWinLevel() {
//player win the level if he has eaten all the pallet
return this.gameMap.countPallets()==0;
}
public void onResume(){
for (int i=0 ; i<this.ghosts.length;i++){
this.ghosts[i].cancelBehavoirThread();
}
if(this.scareCountDown!=null && !this.scareCountDown.hasEnded()){
this.scareCountDown.start();
}
}
public void onPause(){
for (int i=0 ; i<this.ghosts.length;i++){
this.ghosts[i].cancelBehavoirThread();
}
if(this.scareCountDown!=null && !this.scareCountDown.hasEnded()){
this.scareCountDown=this.scareCountDown.onPause();
}
}
public void cancelThreads(){
for (int i=0 ; i<this.ghosts.length;i++){
this.ghosts[i].cancelBehavoirThread();
}
if(this.scareCountDown!=null){
this.scareCountDown.cancel();
}
}
}
My app is a little jump and run game. The moment you die, the activity sleeps for 1 sec. If I touch in that time the screen (so that the OnTouchEvent gets triggered) I get the error "unfortunately app has stopped".
Is there a way to ignore touch events?
public class GamePanel extends SurfaceView implements SurfaceHolder.Callback{
private MainThread thread;
private Background bg;
private Player player;
MediaPlayer mp = MediaPlayer.create(getContext(), R.raw.background_sound);
MediaPlayer copter = MediaPlayer.create(getContext(), R.raw.helicoptersound);
public GamePanel(Context context) {
super(context);
getHolder().addCallback(this);
setFocusable(true);
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
}
#Override
public void surfaceCreated(SurfaceHolder holder) {
setWillNotDraw(false);
bg = new Background(BitmapFactory.decodeResource(getResources(), R.raw.grassbg1), 900);
player = new Player(BitmapFactory.decodeResource(getResources(), R.raw.helicopter), 132, 47, 3);
thread = new MainThread(getHolder(), this);
// start game loop
thread.setRunning(true);
thread.start();
}
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
mp.release();
copter.release();
while (true) {
try {
thread.setRunning(false);
thread.join();
thread = null;
}
catch (InterruptedException e) {
e.printStackTrace();
}
break;
}
}
#Override
public boolean onTouchEvent(MotionEvent event) {
if (((Activity)getContext()) != null) {
if (event.getAction() == MotionEvent.ACTION_DOWN && fuel > 0) {
if (!player.getPlaying()) {
player.setPlaying(true);
player.setUp(true);
}
else {
player.setUp(true);
}
return true;
}
if (event.getAction() == MotionEvent.ACTION_UP) {
copter.pause();
player.setUp(false);
return true;
}
}
return super.onTouchEvent(event);
}
public void update() {
postInvalidate();
if (player.getPlaying()) {
bg.update();
player.update();
// check if player out of range
if (player.getY() > HEIGHT || player.getY() < 0) {
player.setPlaying(false);
newGame(score);
}
}
}
public boolean collision(GameObject a, GameObject b) {
if (Rect.intersects(a.getRectangle(), b.getRectangle())) {
return true;
}
return false;
}
#Override
public void draw(Canvas canvas) {
if (canvas != null) {
bg.draw(canvas);
player.draw(canvas);
}
}
public void newGame(int score) {
mp.release();
copter.release();
try {
thread.setRunning(false);
Thread.sleep(1000);
}
catch (InterruptedException e) {
e.printStackTrace();
}
Bundle basket13 = new Bundle();
basket13.putInt("key2", score);
Context context = getContext();
Intent intent = new Intent(context, MainActivity.class);
intent.putExtras(basket13);
context.startActivity(intent);
((Activity)context).finish(); // letztes was ausgeführt wird
}
}
In my android app i have activity containing a surfaceview. I want to start the surfaceview thread when the surfaceview/activity is visible to user. I have tried starting the thread in OnSurfaceCreated. That works but on some mobiles(samsung) The activity takes many seconds to become visible.The screen turns black when i resume activity. So i googled and found that when a view becomes visible onFocusChanged is called. I tried implementing OnFocusChanged in surfaceview but it is never called. below is my surfaceview class.
public class ImageSurface extends SurfaceView implements SurfaceHolder.Callback {
private DrawThread drawThread;
private SurfaceHolder sHolder;
private ImageHolder imageHolder;
Bitmap mybit;
Bitmap orgiBitmap;// ;)
int message;
Context context;
private String valMagField;
public ImageSurface(Context context, AttributeSet attrs) {
super(context, attrs);
this.context=context;
SurfaceHolder holder = getHolder();
holder.addCallback(this);
setFocusable(true);
clearFocus();
drawThread = new DrawThread(context);
}
public void setImageHolder(ImageHolder imageHolder){
this.imageHolder = imageHolder;
}
public void setBitmap(String filePath){
}
public void resume(){
drawThread.resumeThread();
}
#Override
public void onFocusChanged(boolean focus,int direction,Rect rect){
super.onFocusChanged(focus, direction, rect);
Log.d("in focus changed","onfocuschanged"+System.currentTimeMillis());
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
drawThread.setSurfaceSize(width, height);
resume();
}
#Override
public void surfaceCreated(SurfaceHolder holder) {
long startTime, stopTime;
startTime = System.currentTimeMillis();
sHolder = holder;
drawThread.setRunning(true);
if(drawThread.getState()==Thread.State.NEW){
drawThread.start();
}
if(drawThread.getState()==Thread.State.TERMINATED){
drawThread = new DrawThread(context);
drawThread.setRunning(true);
drawThread.start();
}
}
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
drawThread.pauseThread();
}
class DrawThread extends Thread{
int value=0;
private Boolean drun;
int valSize =30;
Context context;
private int sHeight , sWidth;
int lastmessage;
boolean threadPaused= false;
public DrawThread(Context context){
drun = false;
this.context = context;
}
public void pauseThread(){
synchronized(this){
threadPaused = true;
this.notify();
}
}
public void resumeThread(){
synchronized(this){
threadPaused = false;
this.notify();
}
}
public void setRunning(Boolean run){
drun = run;
}
public boolean isRunning(){
return drun;
}
public void setSurfaceSize(int width , int height){
sWidth = width;
sHeight = height;
}
#Override
public void run(){
while(drun){
Canvas c = null;
//Log.d("yes","thread is running");
try{
synchronized(this){
if(threadPaused)
try {
this.wait();
} catch (InterruptedException e) {
Log.d("in wait of surface view thread","error"+e.toString());
}
}
c = sHolder.lockCanvas(null);
synchronized(sHolder){
updateCanvas(c);
}
}finally {
if(c!=null){
sHolder.unlockCanvasAndPost(c);
}
}
}
}
private void updateCanvas(Canvas canvas){
try{
if(imageHolder.dispBit!= null){
int x=(sWidth-imageHolder.dispBit.getWidth())/2,y=(sHeight-imageHolder.dispBit.getHeight())/2;
imageHolder.applyEffects();
if(canvas!=null)
canvas.drawBitmap(imageHolder.dispBit, x,y,null);
}
else if(imageHolder!=null)
imageHolder.setDisplaySize(sWidth, sHeight);
}catch(Exception e){
e.printStackTrace();
}
}
}
}
In my library project I have the following code to initialize the camera, and start previewing.
public class CameraView {
private SurfaceView preview;
private SurfaceHolder previewHolder;
private Camera camera;
private boolean activeCamera;
private boolean cameraConfigured;
private Activity activity;
private final static int NINTY_DEGREES = 90;
public CameraView(Activity activity) {
this.activity = activity;
View rootView;
LayoutInflater inflater = activity.getLayoutInflater();
rootView = inflater.inflate(R.layout.layout_cameraview, null);
preview = (SurfaceView) rootView.findViewById(R.id.surfaceView);
previewHolder = preview.getHolder();
previewHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
cameraConfigured = false;
}
private void initializeCamera(int w, int h) {
if(camera != null && previewHolder.getSurface() != null) {
try
{
camera.setPreviewDisplay(previewHolder);
}
catch(Exception e)
{
Log.e("Camera: ", e.getMessage());
}
if(!cameraConfigured) {
Camera.Parameters params = camera.getParameters();
Camera.Size size = getBestPreviewSize(w, h, params);
if(size != null) {
params.setPreviewSize(size.width, size.height);
cameraConfigured = true;
}
}
}
}
public void startCamera() {
camera = Camera.open();
previewHolder.addCallback(surfaceCallback);
}
public void stopCamera() {
stopPreviewingOnDisplay();
}
public void takePicture() {
View rootView;
LayoutInflater inflater = activity.getLayoutInflater();
rootView = inflater.inflate(R.layout.layout_cameraview, null);
Button capture = (Button) rootView.findViewById(R.id.capture);
capture.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Log.e("CameraView: ", "Capture button pressed!");
}
});
}
private void startPreviewingOnDisplay() {
if(camera != null) {
camera.setDisplayOrientation(NINTY_DEGREES);
camera.startPreview();
activeCamera = true;
}
}
private void stopPreviewingOnDisplay() {
if(camera != null && activeCamera) {
camera.stopPreview();
activeCamera = false;
}
}
private SurfaceHolder.Callback surfaceCallback = new SurfaceHolder.Callback() {
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
}
#Override
public void surfaceCreated(SurfaceHolder holder) {
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
initializeCamera(width, height);
startPreviewingOnDisplay();
Log.d("CameraView: ", "SurfaceChanged");
}
};
private Camera.Size getBestPreviewSize(int w, int h, Camera.Parameters params) {
Camera.Size result = null;
for(Camera.Size size : params.getSupportedPreviewSizes()) {
if(size.width < w && size.height <= h) {
if(result == null) {
result = size;
}
else {
int resultArea = result.width * result.height;
int newArea = size.width * size.height;
if(newArea > resultArea)
result = size;
}
}
}
return(result);
}
}
The usage of this class:
public class History extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
......
camera = new CameraView(this);
}
#Override
public void onResume() {
super.onResume();
Log.i("History.class", "onResume called!");
camera.startCamera();
}
#Override
public void onPause() {
super.onPause();
camera.stopCamera();
}
}
I've debugged the code, and I notice that the camera object is being intitalized, but there is nothing appearing on the screen, it should have previewed the camera. Could anyone see whats wrong with this approach?
Thanks.
i am using a surface view to draw interactive piechart. here is my code which will looks like all surface view examples.
class PieChart extends SurfaceView implements SurfaceHolder.Callback {
public PieChart(Context context) {
super(context);
// Log.i("PieChart", "PieChart : constructor");
getHolder().addCallback(this);
}
#Override
public void onDraw(Canvas canvas) {
if (hasData) {
resetColor();
try {
canvas.drawColor(getResources().getColor(R.color.graphbg_color));
graphDraw(canvas);
} catch (ValicException ex) {
}
}
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
Log.i("PieChart", "surfaceChanged");
}
public int callCount = 0;
#Override
public void surfaceCreated(SurfaceHolder holder) {
try {
// Log.i("PieChart", "surfaceCreated");
mChartThread = new ChartThread(getHolder(), this);
mChartThread.setRunning(true);
if (!mChartThread.isAlive()) {
mChartThread.start();
}
Rect mFrame = holder.getSurfaceFrame();
mOvalF = new RectF(0, 0, mFrame.right, mFrame.right);
} catch (Exception e) {
// No error message required
}
}
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
// Log.i("PieChart", "surfaceDestroyed");
boolean retry = true;
callCount = 0;
mChartThread.setRunning(false);
while (retry) {
try {
mChartThread.join();
retry = false;
} catch (InterruptedException e) {
// No error message required
}
}
}
}
class ChartThread extends Thread {
private SurfaceHolder mSurfaceHolder;
private PieChart mPieChart;
private boolean mRefresh = false;
public ChartThread(SurfaceHolder surfaceHolder, PieChart pieChart) {
// Log.i("ChartThread", "ChartThread");
mSurfaceHolder = surfaceHolder;
mPieChart = pieChart;
}
public void setRunning(boolean Refresh) {
// Log.i("ChartThread", "setRunning : " + Refresh);
mRefresh = Refresh;
}
#Override
public void run() {
Canvas c;
// Log.i("ChartThread", "run : " + mRefresh);
while (mRefresh) {
c = null;
try {
c = mSurfaceHolder.lockCanvas(null);
// c.drawColor(0xFFebf3f5);
synchronized (mSurfaceHolder) {
mPieChart.onDraw(c);
}
} catch (Exception ex) {
} finally {
// do this in a finally so that if an exception is thrown
// during the above, we don't leave the Surface in an
// inconsistent state
if (c != null) {
mSurfaceHolder.unlockCanvasAndPost(c);
}
}
}
}
}
with this i am able to draw pie charts successfully. but here the issue is "before loading pie chart black rectangle is visible for a second which is surfaceview's default back ground". so I want to set background color for surface view to avoid the black rectangle.
The following is the changed code for drawing background color to surface view.
public PieChart(Context context) {
super(context);
// Log.i("PieChart", "PieChart : constructor");
getHolder().addCallback(this);
setBackgroundColor(getResources().getColor(R.color.graphbg_color));
}
#Override
public void onDraw(Canvas canvas) {
if (hasData) {
setBackgroundColor(getResources().getColor(R.color.graphbg_color));
resetColor();
try {
canvas.drawColor(getResources().getColor(R.color.graphbg_color));
graphDraw(canvas);
} catch (ValicException ex) {
}
}
}
with these changes, black rectangle issue is resolved. but piechart is not refreshing properly. can someone help me to resolve any of these two issues.
class PieChart extends SurfaceView implements SurfaceHolder.Callback {
private int backGroundColor = Color.BLACK;
public PieChart(Context context,int backGroundColor) {
super(context);
setBackGroundColor(backGroundColor);
// Log.i("PieChart", "PieChart : constructor");
getHolder().addCallback(this);
}
public void setBackGroundColor(int color){
this.backGroundColor = color;
}
#Override
public void onDraw(Canvas canvas) {
Paint paint = new Paint();
paint.setStyle(Paint.Style.FILL_AND_STROKE);
paint.setStrokeWidth(3);
paint.setAntiAlias(true);
paint.setColor(backGroundColor);
canvas.drawRect(0, 0, this.getWidth(), this.getHeight(), paint);
if (hasData) {
resetColor();
try {
canvas.drawColor(getResources().getColor(R.color.graphbg_color));
graphDraw(canvas);
} catch (ValicException ex) {
}
}
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
Log.i("PieChart", "surfaceChanged");
}
public int callCount = 0;
#Override
public void surfaceCreated(SurfaceHolder holder) {
try {
// Log.i("PieChart", "surfaceCreated");
mChartThread = new ChartThread(getHolder(), this);
mChartThread.setRunning(true);
if (!mChartThread.isAlive()) {
mChartThread.start();
}
Rect mFrame = holder.getSurfaceFrame();
mOvalF = new RectF(0, 0, mFrame.right, mFrame.right);
} catch (Exception e) {
// No error message required
}
}
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
// Log.i("PieChart", "surfaceDestroyed");
boolean retry = true;
callCount = 0;
mChartThread.setRunning(false);
while (retry) {
try {
mChartThread.join();
retry = false;
} catch (InterruptedException e) {
// No error message required
}
}
}
}
class ChartThread extends Thread {
private SurfaceHolder mSurfaceHolder;
private PieChart mPieChart;
private boolean mRefresh = false;
public ChartThread(SurfaceHolder surfaceHolder, PieChart pieChart) {
// Log.i("ChartThread", "ChartThread");
mSurfaceHolder = surfaceHolder;
mPieChart = pieChart;
}
public void setRunning(boolean Refresh) {
// Log.i("ChartThread", "setRunning : " + Refresh);
mRefresh = Refresh;
}
#Override
public void run() {
Canvas c;
// Log.i("ChartThread", "run : " + mRefresh);
while (mRefresh) {
c = null;
try {
c = mSurfaceHolder.lockCanvas(null);
// c.drawColor(0xFFebf3f5);
synchronized (mSurfaceHolder) {
mPieChart.onDraw(c);
}
} catch (Exception ex) {
} finally {
// do this in a finally so that if an exception is thrown
// during the above, we don't leave the Surface in an
// inconsistent state
if (c != null) {
mSurfaceHolder.unlockCanvasAndPost(c);
}
}
}
}
}
and in yout class client you can use the setBackGroundColor(your color) ;)