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POLoad bitmap into canvas and draw over it
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  1. POLoad bitmap into canvas and draw over it
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    copied!<p>I like to make an app, something like a little paint, I have to get a bitmap, draw it on a canvas and next, draw over it (with figer)... So, I actually have this code:</p> <pre><code>import java.io.File; import java.io.FileOutputStream; import java.util.ArrayList; import android.content.Context; import android.graphics.BitmapFactory; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.Paint; import android.graphics.Path; import android.os.Environment; import android.util.Log; import android.graphics.Bitmap; import android.view.MotionEvent; import android.view.View; import android.view.View.OnTouchListener; public class DrawView extends View implements OnTouchListener { private Canvas mCanvas; private Path mPath; public Paint mPaint; private ArrayList&lt;Path&gt; paths = new ArrayList&lt;Path&gt;(); private boolean start = true; public DrawView(Context context) { super(context); setFocusable(true); setFocusableInTouchMode(true); this.setOnTouchListener((OnTouchListener) this); mPaint = new Paint(); mPaint.setAntiAlias(true); mPaint.setDither(true); mPaint.setColor(Color.BLACK); mPaint.setStyle(Paint.Style.STROKE); mPaint.setStrokeJoin(Paint.Join.ROUND); mPaint.setStrokeCap(Paint.Cap.ROUND); mPaint.setStrokeWidth(4); mPaint.setDither(true); mPaint.setFilterBitmap(true); mCanvas = new Canvas(); mPath = new Path(); paths.add(mPath); } @Override protected void onSizeChanged(int w, int h, int oldw, int oldh) { super.onSizeChanged(w, h, oldw, oldh); } @Override protected void onDraw(Canvas canvas) { for (Path p : paths) { canvas.drawPath(p, mPaint); } if (start) { Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.v01); canvas.drawBitmap(bmp, 0, 0, mPaint); start = false; } } private float mX, mY; private static final float TOUCH_TOLERANCE = 4; private void touch_start(float x, float y) { mPath.reset(); mPath.moveTo(x, y); mX = x; mY = y; } private void touch_move(float x, float y) { float dx = Math.abs(x - mX); float dy = Math.abs(y - mY); if (dx &gt;= TOUCH_TOLERANCE || dy &gt;= TOUCH_TOLERANCE) { mPath.quadTo(mX, mY, (x + mX) / 2, (y + mY) / 2); mX = x; mY = y; } } private void touch_up() { mPath.lineTo(mX, mY); // commit the path to our offscreen mCanvas.drawPath(mPath, mPaint); // kill this so we don't double draw mPath = new Path(); paths.add(mPath); } public boolean onTouch(View arg0, MotionEvent event) { float x = event.getX(); float y = event.getY(); switch (event.getAction()) { case MotionEvent.ACTION_DOWN: touch_start(x, y); invalidate(); break; case MotionEvent.ACTION_MOVE: touch_move(x, y); invalidate(); break; case MotionEvent.ACTION_UP: touch_up(); invalidate(); break; } return true; } } </code></pre> <p>With this code I can draw over the canvas, and get the bitmap by first way... But, if I touch over, the bitmap dissapears, that's cause on each onTouch event I draw again based on the path... How can I do what I like?, I mean, get the Bitmap, and draw over it... </p>
 

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