I have created a class from SurfaceView.I wanted it that when i touch on the screen then the screen will be refreshed by calling invalidate() function. But in my implementation invalidate () is not called when i touched on the screen.
Here is my code.
public class GameBoard extends SurfaceView implements Callback {
private SurfaceHolder holder;
int clicked =0;
public GameBoard(Context context)
{
super(context);
holder = getHolder();
holder.addCallback(this);
setFocusable(true);
requestFocus();
}
#Override
public void surfaceCreated(SurfaceHolder holder)
{
Canvas c = holder.lockCanvas(null);
onDraw(c);
holder.unlockCanvasAndPost(c);
}
#Override
public void surfaceDestroyed(SurfaceHolder holder)
{
// TODO Auto-generated method stub
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height)
{
}
public boolean onTouchEvent(MotionEvent event)
{
int action = event.getAction();
if (action==MotionEvent.ACTION_UP)
{
clicked++;
// Canvas c = holder.lockCanvas(null);
// onDraw(c);
// holder.unlockCanvasAndPost(c);
invalidate();
}
return true;
}
#Override
protected void onDraw(Canvas canvas)
{
canvas.drawColor(0xFF00ff00);
Paint p = new Paint();
p.setTextSize(20);
p.setColor( Color.RED );
p.setAntiAlias(true);
canvas.drawText(""+clicked, 100, 500, p);
}
}
Related
i want to add image on surfaceview and make it as clickable. I could do it via xml using layout. But i am not able to do it dynamically from code. I even cannot use lockcanvas to draw image on canvas since i set my SurfaceHolder type to SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS.So what i have to do to draw image on surfaceview in my app. Pls guide me?
Some thing like that
public class MSurface extends SurfaceView implements SurfaceHolder.Callback {
public MSurface(Context context) {
super(context);
getHolder().addCallback(this);
}
#Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
Bitmap icon = BitmapFactory.decodeResource(getResources(),R.drawable.icon);
canvas.drawColor(Color.BLACK);
canvas.drawBitmap(icon, 10, 10, new Paint());
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
// TODO Auto-generated method stub
}
#Override
public void surfaceCreated(SurfaceHolder holder) {
Canvas canvas = null;
try {
canvas = holder.lockCanvas(null);
synchronized (holder) {
onDraw(canvas);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (canvas != null) {
holder.unlockCanvasAndPost(canvas);
}
}
}
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
// TODO Auto-generated method stub
}
}
I am trying an example having SurfaceView. I have inherited my class from SurfaceView and using as follows:
public class MySurfaceView extends SurfaceView implements SurfaceHolder.Callback {
Context context;
MySurfaceViewThread mThread;
SurfaceHolder holder;
Paint paint;
int x = 20, y = 20, r = 10;
public void init() {
holder = getHolder();
holder.addCallback(this);
mThread = new MySurfaceViewThread(getHolder(), this);
paint = new Paint();
paint.setStyle(Style.STROKE);
paint.setStrokeCap(Cap.ROUND);
paint.setStrokeWidth(1);
paint.setColor(Color.rgb(255, 255, 255));
}
public MySurfaceView(Context context) {
super(context);
// TODO Auto-generated constructor stub
this.context = context;
init();
}
public MySurfaceView(Context context, AttributeSet attr) {
super(context,attr);
this.context = context;
init();
}
public MySurfaceView(Context context, AttributeSet attr, int defStyle) {
super(context, attr, defStyle);
this.context = context;
init();
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
// TODO Auto-generated method stub
}
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
// TODO Auto-generated method stub
mThread.isRunning = false;
while (true) {
try {
mThread.join();
break;
} catch (Exception e) {
e.printStackTrace();
}
}
}
#Override
public void onDraw(Canvas canvas) {
// super.onDraw(canvas);
// canvas.drawColor(0, Mode.CLEAR);
x += 2;
y += 2;
r += 3;
canvas.drawColor(Color.rgb(x%255, y%255, (x+y)%255));
canvas.drawCircle(x, y, r, paint);
canvas.drawText("x:"+x, 100, 100, paint);
Log.d("onDraw","onDraw()"+"x:"+x + ",y:"+y+",r:"+r);
}
#Override
public void surfaceCreated(SurfaceHolder holder) {
// TODO Auto-generated method stub
Log.d("surfaceCreated", "surfaceCreated()");
mThread.isRunning = true;
mThread.start();
}
}
I am updating my Canvas from a Thread which is:
public class MySurfaceViewThread extends Thread {
SurfaceHolder holder;
MySurfaceView surfaceView;
boolean isRunning = false;
public MySurfaceViewThread(SurfaceHolder holder, MySurfaceView surfaceView) {
Log.d("thread","thread constructor");
this.holder = holder;
this.surfaceView = surfaceView;
}
#Override
public void run() {
Log.d("run","run()");
while(isRunning) {
Canvas canvas = null;
try {
canvas = holder.lockCanvas();
synchronized(holder) {
surfaceView.onDraw(canvas);
}
sleep(1000);
} catch (InterruptedException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
finally {
holder.unlockCanvasAndPost(canvas);
Log.d("canvas status", "canvas unlocaked...");
}
}
}
}
When application starts and its onDraw() is called, it draws circle and text as well but on further calls to onDraw() it draws nothing. Means nothing changed on screen after first update. Any idea where I am getting wrong? I am new to android and slow learner as well.
I got the answer. Its very strange. I don't know why this worked.
I commented the following line from my activity and it runs.
surfaceView.setBackgroundColor(Color.rgb(0, 255, 0));
the activity code is:
public class SurfaceViewTutorialActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
MySurfaceView surfaceView = new MySurfaceView(this);
// surfaceView.setBackgroundColor(Color.rgb(0, 255, 0));
surfaceView.setBitmap(BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher));
setContentView(surfaceView);
}
}
If any one knows about this, kindly guide me to the right direction.
i want to rotate an image(png) in android depending upon the intensity of touch.
Any Idea?
public class GetmouseActivity extends Activity {
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(new Panel(this));
}
public class Panel extends SurfaceView implements SurfaceHolder.Callback {
private Bitmap mBitmap;
private ViewThread mThread;
private int mX;
private int mY;
public Panel(Context context) {
super(context);
mBitmap = BitmapFactory.decodeResource(getResources(),
R.drawable.icon);
getHolder().addCallback(this);
mThread = new ViewThread(this);
}
public void doDraw(Canvas canvas) {
canvas.drawColor(Color.BLACK);
Paint paint = new Paint();
paint.setStrokeWidth(25);
for (int y = 30, alpha = 255; alpha > 2; alpha >>= 1, y += 10) {
paint.setAlpha(alpha);
canvas.drawLine(0, y, 100, y, paint);
}
canvas.drawBitmap(mBitmap, mX, mY, null);
}
public void surfaceChanged(SurfaceHolder holder, int format, int width,
int height) {
// TODO Auto-generated method stub
}
public void surfaceCreated(SurfaceHolder holder) {
if (!mThread.isAlive()) {
mThread = new ViewThread(this);
mThread.setRunning(true);
mThread.start();
}
}
public void surfaceDestroyed(SurfaceHolder holder) {
if (mThread.isAlive()) {
mThread.setRunning(false);
}
}
#Override
public boolean onTouchEvent(MotionEvent event) {
mX = (int) event.getX() - mBitmap.getWidth() / 2;
mY = (int) event.getY() - mBitmap.getHeight() / 2;
return super.onTouchEvent(event);
}
}
public class ViewThread extends Thread {
private Panel mPanel;
private SurfaceHolder mHolder;
private boolean mRun = false;
public ViewThread(Panel panel) {
mPanel = panel;
mHolder = mPanel.getHolder();
}
public void setRunning(boolean run) {
mRun = run;
}
#Override
public void run() {
Canvas canvas = null;
while (mRun) {
canvas = mHolder.lockCanvas();
if (canvas != null) {
mPanel.doDraw(canvas);
mHolder.unlockCanvasAndPost(canvas);
}
}
}
}
}
try this
I am trying to draw on a surface view, but I get a black screen. My xml layout:
<?xml version="1.0" encoding="utf-8"?>
<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent" android:layout_height="match_parent">
<com.example.surfaceview.MySurface android:id="#+id/padview"
android:layout_width="match_parent" android:layout_height="match_parent" />
</FrameLayout>
Important parts of my code: MySurface.java
public class MySurface extends SurfaceView implements SurfaceHolder.Callback {
public DrawingThread thread;
public MySurface(Context context, AttributeSet attrs) {
super(context, attrs);
SurfaceHolder surfaceholder = getHolder();
surfaceholder.addCallback(this);
thread = new DrawingThread(surfaceholder, context, new Handler() {
#Override
public void handleMessage(Message m) {
// Do some handle thing
}
});
setFocusable(true);
}
#Override
public void surfaceChanged(SurfaceHolder tholder, int format, int width, int height) {
thread.setSurfaceSize(width, height);
thread.holder = tholder;
}
#Override
public void surfaceCreated(SurfaceHolder holder) {
thread.running = true;
thread.start();
}
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
boolean retry = true;
thread.running = false;
while(retry) {
try {
thread.join();
retry = false;
} catch (InterruptedException e) {
}
}
}
public Thread getThread() {
return thread;
}
public class DrawingThread extends Thread {
private SurfaceHolder holder;
private Context context;
private Handler handle;
private Paint background;
private Rect blank;
public boolean running;
public boolean created;
public int canvasheight;
public int canvaswidth;
public PadThread(SurfaceHolder tholder, Context tcontext, Handler thandler) {
holder = tholder;
context = tcontext;
handle = thandler;
// Temporary canvas dimentions
canvaswidth = 1;
canvasheight = 1;
running = false;
created = false;
background = new Paint();
background.setColor(R.color.white);
blank = new Rect(0, 0, canvaswidth, canvasheight);
}
#Override
public void run() {
Log.d("SurfaceView Test", "Drawing thread run");
while(running) {
Canvas canvas = null;
try {
canvas = holder.lockCanvas();
synchronized(holder) {
// update object states
// get user input gestures
drawing(canvas);
}
} finally {
if(canvas != null) {
holder.unlockCanvasAndPost(canvas);
}
}
}
}
private void drawing(Canvas canvas) {
// Clear screen
canvas.drawRect(blank, background);
// Draw Things
}
public void setSurfaceSize(int width, int height) {
synchronized(holder) {
canvaswidth = width;
canvasheight = height;
// New background rect
blank.set(0, 0, canvaswidth, canvasheight);
}
}
}
}
The code is based off of Google's Lunar Landar SurfaceView example at http://developer.android.com/resources/samples/LunarLander/index.html
I know that all of the code is being reached through logging.
change drawing function
background.setColor(Color.RED);
canvas.drawRect(new Rect(10, 10, 100, 100), background);
(There are test values for colors and rect)
I'm new in android. I want to move an image from left to right and right to left.When user touch right side image of the image it will move right side.Same thing will happen when user will touch right side of the image.But image will move predefine point across x-axis.
For example: Image will move p1(100,100), p2(150,100), p3(200,100), p4(250,100) across those points sequentially. If user touch left side of p1, it will remain current position.Same thing will occurs at p4. I can move image from p1 to p2 and p2 to p1. when I add p3 and p4 it's not working as I expected.
Here is my GameView class.
public class GameView extends SurfaceView{
private Bitmap BG_image;
private SurfaceHolder holder;
//private GameLoopThread gameLoopThread;
int x;
int y;
private int srcX=100;
private int srcY=100;
int replaceX=0,areaThreshold=50;
int distance=50;
public GameView(Context context) {
super(context);
//gameLoopThread = new GameLoopThread(this);
holder = getHolder();
holder.addCallback(new SurfaceHolder.Callback() {
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
/* boolean retry = true;
gameLoopThread.setRunning(false);
while (retry) {
try {
gameLoopThread.join();
retry = false;
} catch (InterruptedException e) {
}
}*/
}
#Override
public void surfaceCreated(SurfaceHolder holder) {
/* gameLoopThread.setRunning(true);
gameLoopThread.start();*/
Canvas c = holder.lockCanvas(null);
onDraw(c);
holder.unlockCanvasAndPost(c);
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format,
int width, int height) {
}
});
BG_image = BitmapFactory.decodeResource(getResources(), R.drawable.icon);
Bitmap.createScaledBitmap(BG_image, BG_image.getWidth(), BG_image.getHeight(), false);
}
#Override
public boolean onTouchEvent(MotionEvent ev) {
// TODO Auto-generated method stub
// x = (int) ev.getX();
// y = (int) ev.getY();
updateX(srcX);
replaceX=(int)ev.getX();
int StartX=0, EndX=0;
StartX=replaceX-areaThreshold;
EndX=replaceX+areaThreshold;
if(StartX<=100){
SurfaceHolder holder=getHolder();
Canvas myCanvas=holder.lockCanvas(null);
onDraw(myCanvas);
holder.unlockCanvasAndPost(myCanvas);
srcX=100;
}
else if(StartX>100 && StartX<250){
SurfaceHolder holder=getHolder();
Canvas myCanvas=holder.lockCanvas(null);
onDraw(myCanvas);
holder.unlockCanvasAndPost(myCanvas);
srcX=srcX+distance;
}
if(EndX>100 && EndX<250){
SurfaceHolder holder=getHolder();
Canvas myCanvas=holder.lockCanvas(null);
onDraw(myCanvas);
holder.unlockCanvasAndPost(myCanvas);
srcX=srcX-distance;
}
else if(EndX>250){
SurfaceHolder holder=getHolder();
Canvas myCanvas=holder.lockCanvas(null);
onDraw(myCanvas);
holder.unlockCanvasAndPost(myCanvas);
srcX=250;
}
return super.onTouchEvent(ev);
}
#Override
protected void onDraw(Canvas canvas) {
// TODO Auto-generated method stub
updateX(srcX);
Paint paint = new Paint();
canvas.drawColor(Color.BLACK);
canvas.drawRect(new Rect(0,0,getWidth(),getHeight()),paint);
canvas.drawBitmap(BG_image, srcX, srcY, null);
}
private int updateX(int srcX){
this.srcX =srcX;
return srcX ;
}
}
Please review my code and give your valuable advice to solve my problem.
Hopefully, I will get a reply soon!
This is very easy with Android TranslateAnimation
ImageView img_animation = (ImageView) findViewById(R.id.img_animation);
TranslateAnimation animation = new TranslateAnimation(0.0f, 400.0f,
0.0f, 0.0f); // new TranslateAnimation(xFrom,xTo, yFrom,yTo)
animation.setDuration(5000); // animation duration
animation.setRepeatCount(5); // animation repeat count
animation.setRepeatMode(2); // repeat animation (left to right, right to left )
//animation.setFillAfter(true);
img_animation.startAnimation(animation); // start animation
find more details from here move an image from left to right and right to left in android
Now, I understand my problem. Thank you very much to give your suggestion.
Here is my updated code.
public class GameView extends SurfaceView{
private Bitmap BG_image;
private SurfaceHolder holder;
int x=100;
private int srcX=100;
private int srcY=100;
int distance=50;
public GameView(Context context) {
super(context);
holder = getHolder();
holder.addCallback(new SurfaceHolder.Callback() {
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
}
#Override
public void surfaceCreated(SurfaceHolder holder) {
Canvas c = holder.lockCanvas(null);
onDraw(c);
holder.unlockCanvasAndPost(c);
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format,
int width, int height) {
}
});
BG_image = BitmapFactory.decodeResource(getResources(), R.drawable.icon);
Bitmap.createScaledBitmap(BG_image, BG_image.getWidth(), BG_image.getHeight(), false);
}
#Override
public boolean onTouchEvent(MotionEvent ev) {
// TODO Auto-generated method stub
x = (int) ev.getX();
if(x-srcX>0)
srcX += distance;
else if(x-srcX<0)
srcX -= distance;
if(srcX<=100)
srcX = 100;
else if(srcX>250)
srcX = 250;
Log.w("ev.getX : srcX",x+" : "+srcX);
SurfaceHolder holder=getHolder();
Canvas myCanvas=holder.lockCanvas(null);
onDraw(myCanvas);
holder.unlockCanvasAndPost(myCanvas);
return super.onTouchEvent(ev);
}
#Override
protected void onDraw(Canvas canvas) {
// TODO Auto-generated method stub
Paint paint = new Paint();
canvas.drawColor(Color.BLACK);
canvas.drawRect(new Rect(0,0,getWidth(),getHeight()),paint);
canvas.drawBitmap(BG_image, srcX-BG_image.getWidth()/2, srcY, null);
}
}