I am new to android Surfaceview implementation. I am developing RDP client application in android3.0. I getting the image stream from socket, drawing this image to surface using Surfaceview and Thread.
The sample code of surface view:
class mySurfaceView extends SurfaceView implements SurfaceHolder.Callback
{
private TutorialThread _thread;
Canvas c=null;
public mySurfaceView(Context context)
{
super(context);
getHolder().addCallback(this);
_thread = new TutorialThread(getHolder(), this);
matrix= new Matrix();
m = new float[9];
paint = new Paint();
}
public void surfaceCreated(SurfaceHolder arg0) {
//setWillNotDraw(false) ;
Log.e("surfaceCreated","surfaceCreated");
if(_thread==null ){
Log.e("_thread.created","thread created");
_thread = new TutorialThread(getHolder(),this);
_thread.setRunning(true);
_thread.start();
// <-- added fix
}else {
Log.e("_thread.getState()",_thread.getState()+"");
_thread.setRunning(true); //original code
_thread.start(); //original code
}
}
public void surfaceDestroyed(SurfaceHolder arg0) {
Log.e("surfaceDestroyed","surfaceDestroyed");
boolean retry = true;
_thread.setRunning(false);
while (retry) {
try {
_thread.join();
retry = false;
} catch (InterruptedException e) {
}
}
}
public void surfaceChanged(SurfaceHolder arg0, int arg1, int arg2,
int arg3) {
}
class TutorialThread extends Thread
{
private SurfaceHolder _surfaceHolder;
private mySurfaceView _panel;
private boolean _run = false;
private InputStream is;
private Socket socket;
Bitmap resizeBmp;
public TutorialThread(SurfaceHolder surfaceHolder,mySurfaceView panel)
{
Log.e("TutorialThread","TutorialThread-->Constructor");
_surfaceHolder = surfaceHolder;
_panel = panel;
}
public void setRunning(boolean run) {
_run = run;
}
@Override
public void run()
{
Log.e("TutorialThread","TutorialThread-->run()");
try
{
socket = new Socket("172.19.1.144", 4444);
is = socket.getInputStream();
DataInputStream inputputStream = new DataInputStream(is);
//long time = System.currentTimeMillis();
int i=0;
while (socket.isConnected() )
{
Log.e("tutorial thread","While running");
c = null;
i++;
if(i==10){
System.gc();
i=0;
}
Log.e("BEFORE","BEFORE");
synchronized (_surfaceHolder)
{
Log.e("AFTER","AFTER");
ByteBuffer inputHeaderBuffer = ByteBuffer.allocate(20);
inputHeaderBuffer.order(ByteOrder.LITTLE_ENDIAN);
inputputStream.readFully(inputHeaderBuffer.array());
SurfaceViewPinchZoom.serverWidth=inputHeaderBuffer.getInt();
SurfaceViewPinchZoom.serverHeight=inputHeaderBuffer.getInt();
//Log.e("serverWidth","serverWidth "+ SurfaceViewPinchZoom.serverWidth+"serverHeight===="+SurfaceViewPinchZoom.serverHeight);
SurfaceViewPinchZoom.left=inputHeaderBuffer.getInt();
SurfaceViewPinchZoom.top=inputHeaderBuffer.getInt();
int dataLength = inputHeaderBuffer.getInt();
ByteBuffer imageDataCompress = ByteBuffer.allocate(dataLength);
imageDataCompress.order(ByteOrder.LITTLE_ENDIAN);
inputputStream.readFully(imageDataCompress.array());
byte[] imagedata = new byte[imageDataCompress.remaining()];
imageDataCompress.get(imagedata);
//Decompress the image
//Log.e("imagedata.length::::::::::",imagedata.length+"");
// Create the decompressor and give it the data to compress
Inflater decompressor = new Inflater();
decompressor.setInput(imagedata);
// Create an expandable byte array to hold the decompressed data
ByteArrayOutputStream bos = new ByteArrayOutputStream(imagedata.length);
// Decompress the data
byte[] buf = new byte[1024];
while (!decompressor.finished()) {
try {
int count = decompressor.inflate(buf);
bos.write(buf, 0, count);
} catch (DataFormatException e) {
}
}
try {
bos.close();
} catch (IOException e) {
}
// Get the decompressed data
byte[] decompressedData = bos.toByteArray();
/
BitmapFactory.Options options=new BitmapFactory.Options();
options.inJustDecodeBounds=true;
// Log.e("decompressedData.length::::::::::",decompressedData.length+"");
/*SurfaceViewPinchZoom.*/bmp = BitmapFactory.decodeByteArray(decompressedData, 0,decompressedData.length,options);
options.inDither=true;
/*scaleX=(float)screen_width/bmp.getWidth();
scaleY=(float)screen_height/bmp.getHeight();
matrix.setScale(scaleX, scaleY);*/
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, screen_width, screen_height);
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
/*SurfaceViewPinchZoom.*/bmp= BitmapFactory.decodeByteArray(decompressedData, 0,decompressedData.length,options);
bmp=BitmapFactory.decodeByteArray(decompressedData, 0,decompressedData.length,options);
c = _surfaceHolder.lockCanvas();
c.drawBitmap(bmp, matrix, paint);
//draw(c);
//postInvalidate();
onDraw(c);
inputHeaderBuffer.clear();
imageDataCompress.clear();
inputHeaderBuffer = null;
imageDataCompress = null;
imagedata = null;
}
if (c != null)
{
_surfaceHolder.unlockCanvasAndPost(c);
}
}
}
catch (ArrayIndexOutOfBoundsException ae)
{
ae.printStackTrace();
}
catch (Exception e)
{
e.printStackTrace();
}
finally {
if (c != null) {
_surfaceHolder.unlockCanvasAndPost(c);
}
}
}
private int calculateInSampleSize(Options options, int screen_width,
int screen_height) {
// Raw height and width of image
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > screen_height || width > screen_width) {
if (width > height) {
inSampleSize = Math.round((float)height / (float)screen_height);
} else {
inSampleSize = Math.round((float)width / (float)screen_width);
}
}
return inSampleSize;
}
}
}
The problems are
1) if I press home button then surfaceDestroyed() is called and thread is terminated.
But I need to continue the Thread and update the images(input stream from socket) after open the application from home button is pressed.
2) if I call the activity on doubletap event as child activity, surfaceDestroyed() is called and Thread is terminated.
Where I need to continue the images display after returning from child activity.
In both the case I am getting exception as java.lang.IllegalThreadStateException: Thread already started.
Could please help how to run the same thread without terminating on home button is pressed or another child activity is called?
Thanks & Regards Yamini
