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POMulti-threading in the same Canvas
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copied!<p>Well, I'll try to explain exactly what I pretend:</p> <p>I want to draw a bitmap in a canvas in random positions according to the coordinates of the screen on touch, and I want a message(text) to be displayed everytime the user touches the screen. </p> <p>So, if a draw the text in the same thread than I do for the bitmap, it will appear and dissapear right after, and I want it to stay in the screen for a few seconds and the dissapear. My first idea was to use Thread.sleep(), but for that I have to create a thread only for the text, or I will mess with the Bitmap too. </p> <p>I've been trying to use multithreading in the same canvas, but I don't know how. Can someone please explain to me... </p> <p>That's some of the code i've got so far: </p> <pre><code>private void init() { // CREATE SURFACEHOLDER AND ADD THIS CLASS AS HIS CALLBACK enemyHolder = getHolder(); enemyHolder.addCallback(this); scoreHolder = getHolder(); scoreHolder.addCallback(this); hasSurface = false; } </code></pre> <p>public void resume() {</p> <pre><code> if (surfaceViewThread == null) { surfaceViewThread = new SurfaceViewThread(); // CREATE A NEW // THREAD if (hasSurface) surfaceViewThread.start(); // START OUR THREAD } if (secondThread == null) { secondThread = new SecondThread(); if (hasSurface) secondThread.start(); } } public void surfaceCreated(SurfaceHolder holder) { hasSurface = true; if (surfaceViewThread != null) surfaceViewThread.start(); if (scoreShow == 1) { if (secondThread != null) secondThread.start(); } } </code></pre> <p>// THREAD</p> <pre><code> private final class SurfaceViewThread extends Thread { private boolean done; SurfaceViewThread() { super(); done = false; } @Override public void run() { // TODO Auto-generated method stub super.run(); SurfaceHolder surfaceHolder = enemyHolder; while (!done) { Canvas canvas = surfaceHolder.lockCanvas(); canvas.drawColor(Color.WHITE); canvas.drawBitmap(enemy1, enemy1X, enemy1Y, null); // DRAW // FIRST // ENEMY // SECOND THREAD private final class SecondThread extends Thread { private boolean done; SecondThread() { super(); done = false; } @Override public void run() { // TODO Auto-generated method stub super.run(); SurfaceHolder surfaceHolder = scoreHolder; while (!done) { Canvas canvas = surfaceHolder.lockCanvas(); Paint paint = new Paint(); paint.setColor(Color.BLACK); canvas.drawText("xD", 50, 50, paint); surfaceHolder.unlockCanvasAndPost(canvas); try { Thread.sleep(1000); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } scoreShow = 0; } } </code></pre>

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