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drawBitmap() of canvas gives white image on parent image android

I'm newbie with canvas.
I'm trying to draw child bitmap on parent bitmap using canvas.drawbitmap(childbitmap,matrix,point) method. I'm getting number of bitmaps using loop and trying to overlay image on all that bitmaps But somehow the output which I got haven't original child image. It looks like white image. so I'm able to seen child image on parent one but don't know why it looks like this?
Let me put my code over here with output image.
Canvas mCanvas = new Canvas(bitmap);
Paint p = new Paint();
Bitmap icon = BitmapFactory.decodeResource(getApplicationContext().getResources(),
R.drawable.ic_launcher);
mCanvas.drawBitmap(icon,0,0,p);
This above code will run with loop and it will give multiple "bitmap" object on which I have to draw canvas. So now I'm taking launcher icon as child bitmap.while checking final output it shows like below image :
Check the white image instead of launcher icon.So what's wrong with my code?
Waiting for your best suggestion ASAP.

You are drawing your bitmap on top with the current canvas. So you have to call mCanvas.drawBitmap a second time to draw the foreground bitmap.

Set Picture into RemoteViews

I have some SVGs in my assets folder and I need to dynamically set them in my widget (on an ImageView).
I am using this library: http://code.google.com/p/svg-android/
This library returns a Picture or a PictureDrawable.
The only methods I can see to use on RemoteViews are setImageViewBitmap which obviously takes a bitmap.
I tried looking for code to convert a Drawable to a Bitmap like this:
PictureDrawable pictureDrawable = svg.createPictureDrawable();
Bitmap bitmap = Bitmap.createBitmap(pictureDrawable.getIntrinsicWidth(), pictureDrawable.getIntrinsicHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
canvas.drawPicture(pictureDrawable.getPicture());
currentBitmap = bitmap;
But the bitmap is too small. When I create the bitmap in Illustrator I set the artboard size to 65 which is what comes through on the intrinsic width/height.
My widgets can be resized so the ImageView sizes are variable. Even if I set the width and height statically to some large number like this...
Bitmap bitmap = Bitmap.createBitmap(300, 300, Config.ARGB_8888);
then the resulting bitmap just has a bunch of whitespace below and to the right of a tiny image.
I guess I need to somehow draw the picture at a scaled up value as well as creating the Bitmap at size 300. Ideally I could figure out the size of the ImageView at runtime and set the proper sized Bitmap if I knew that. Is this the best approach and how would I do this? Perhaps there is a better approach I don't even know about?

I've not used android-svg but if it's using vanilla PictureDrawables, then it should be just a matter of not using the intrinsic bounds.
Try the following:
PictureDrawable pictureDrawable = svg.createPictureDrawable();
Bitmap bitmap = Bitmap.createBitmap(300, 300, Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
pictureDrawable.setBounds(0, 0, bitmap.getWidth(), bitmap.getHeight());
pictureDrawable.draw(canvas); // do not access the Picture directly, that defeats the purpose
currentBitmap = bitmap;
In short, use the Drawable, not its Picture and set the Drawable's bounds to be the full canvas.

Have you tried createScaledBitmap?
createScaledBitmap()

I have tried svg-android and it has not worked for me for this very reason. Not to mention its severely limited feature set.
The point of using vector graphics is that I can generate images of any appropriate size to fit the UI View size. Which means the generation method must accept the size requirements at run-time, and not always use width,height declared in <svg> tag.
Hence I used the native implementation: libsvg-android, which exactly does that.
It directly renders to a canvas with given size:
long objId = SvgRaster.svgAndroidCreate();
SvgRaster.svgAndroidParseBuffer(objId, readString(mInputStream, "UTF-8"));
SvgRaster.svgAndroidSetAntialiasing(objId, true);
SvgRaster.svgAndroidRenderToArea(objId, mCanvas, 0, 0, mWidth, mHeight);

I ended up modifying the underlying Artboard size to be 300. None of the scaling up methods worked. So the final code I used was that which I originally posted:
PictureDrawable pictureDrawable = svg.createPictureDrawable();
Bitmap bitmap = Bitmap.createBitmap(pictureDrawable.getIntrinsicWidth(), pictureDrawable.getIntrinsicHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
canvas.drawPicture(pictureDrawable.getPicture());
currentBitmap = bitmap;
Once I had a 300x300 Bitmap I was able to set it into the RemoteViews using setImageViewBitmap .
This kind of defeated the purpose of using SVGs in the first place (at least as far as using them in widgets was concerned).
My problem was not the same as User117. Perhaps he did not name the outer layer 'bounds' as was required in the library. Either way, I managed to get the library working, albeit by having to modify the SVG Artboard size.
Hopefully with the increase in screen resolution Android will introduce SVGs as part of the platform soon.

Android - Extend a Bitmap to use as MapMarker

I want to use downloaded images as markers on a MapView. I images are all squares but I would like the bottom to also extend to form a triangle marking the exact point.
My approach was to create a canvas which is slightly larger than the image. Then, draw the bitmap on to the canvas and then somehow pick the color from the bottom of the bitmap and draw a triangular shape from the horizontal center of the image to the bottom of the canvas. Something like this...
As you might guess I'm stuck with the last part. So far I have....
Bitmap canvasBitmap = Bitmap.createBitmap(markerBitmap.getWidth(), markerBitmap.getHeight()+10, Bitmap.Config.ARGB_8888);
// The 10 pixels will be the so called "pin"
Canvas canvas = new Canvas(canvasBitmap);
canvas.drawBitmap(markerBitmap, 0.0f, 0.0f, null);
// Can figure out how to draw the 10 px bottom using the color from markerBitmap
Help !!

Is there any specific reason why you want to create the images dynamically? If not, why don't you create them using a graphics editing program, save them as png's or 9-patch images and then simply assign it to the Drawable that's used for the marker.

Tiling a Bitmap on a Canvas

I would like to create a 'graph paper' look to the Bitmap I am drawing via a Canvas, and trying to figure out the best way to do this.
I can't pass a source Bitmap containing the graph paper background to the Canvas constructor, as I am getting the Canvas in a SurfaceView via the .lockCanvas() call.
Some solutions I've tried:
I've tried implementing this solution in my SurfaceView's Thread.run(), but the issue I believe is when the BitmapDrawable is converted to a Bitmap... it loses the tiling properties.
canvas = mSurfaceHolder.lockCanvas(null);
BitmapDrawable TileMe = new BitmapDrawable(BitmapFactory.decodeResource(getResources(), R.drawable.editor_graph));
TileMe.setTileModeX(Shader.TileMode.REPEAT);
TileMe.setTileModeY(Shader.TileMode.REPEAT);
Bitmap b = TileMe.getBitmap();
canvas.drawBitmap(b, 0, 0, null);
If I use the Canvas.drawBitmap method that takes a destination RectF as a parameter, it looks like the bitmap will be tiled to fill the RectF... but how do I declare a RectF reliably that fills the entire view area?
Setting the Activities background to the desired graph paper look also doesn't work, as the bitmap/canvas layout is opaque and blocks that from being seen.
Any ideas how to achieve this?

You have two easy solutions:
Either use a BitmapDrawable, but instead of extracting the Bitmap, just call BitmapDrawable.draw(Canvas). Don't forget to set the drawable's bounds to fill your drawing area.
Create a Paint with a BitmapShader and draw a rectangle with it (this is basically what BitmapDrawable does).

I'm sure there is a way to get a tiled effect using a SurfaceView. Unfortunately, it looks like you can't use the BitmapDrawable with a canvas. So you would probably have to implement you own custom tiling method by creating your own series of Rect's on the Canvas and drawing a scaled bitmap to each one.
It honestly wouldn't be that hard. Just get the width/height of the view, and create an array of Rect's based on this data that you will draw the Bitmap to.
Alternatively, if you don't need to make modifications to the actual tiled background on the fly, just draw it as a background and draw the SurfaceView on top of it. That post you linked provided multiple solutions to tiling a BitmapDrawable that you could implement.

multiple images in a one single image

I want to create a bitmap / image which has many images like "Collage" which has more then one images in a single picture.
I have stored all my images in a grid view but now i want to create a single image from all those images. And even i want to make few images click able
so what can be the road map to do this ? any sort of help / example will be helpful.
reference image

Bitmap pic1 = BitmapFactory.decodeResource(getResources(), R.drawable.pic1);
Bitmap pic2 = BitmapFactory.decodeResource(getResources(), R.drawable.pic2);
Bitmap bg= BitmapFactory.decodeResource(getResources(), R.drawable.background);
Bitmap out1 = Bitmap.createBitmap(bg) ;
Canvas comboImage = new Canvas(out1);
comboImage.drawBitmap(pic1, 10f, 20f, null);
comboImage.drawBitmap(pic2, 30f, 40f, null);
out1 will have pic1 & pic2, with a background image bg.

To create a single image from multiple images look at using Canvas. You can put bitmaps (and drawables) on a canvas. You can commit the changes and then push then to a single bitmap that you can then use. As far as making certain sections clickable after making it one single image, I will leave this up to someone else to explain, I am not worked directly with the ontouch() functions.