In case anyone else doesn't have a nice test case for you, here are some of the methods that you will be looking at (I just threw this together from the sourcecode for my Animated GIFs project, so it isn't really a complete working example):
import android.graphics.Bitmap;
Bitmap image = Bitmap.createBitmap( textureWidth, textureHeight, Bitmap.Config.ARGB_4444 );
int[] pixels = new int[image.getWidth() * image.getHeight()];
// Of course you can draw whatever you like into the pixels array. Some other useful things:
// To copy the contents of the pixels array onto the Bitmap:
image.setPixels( pixels, 0, image.getWidth(), 0, 0, image.getWidth(), image.getHeight() );
// If you want to clear the bitmap:
if( useAlpha )
image.eraseColor( Color.TRANSPARENT );
else
image.eraseColor( Color.BLACK );
// Or if you have a "background" image that you always want to start with:
background.getPixels( pixels, 0, background.getWidth(), 0, 0,
background.getWidth(), background.getHeight() );
image.setPixels( pixels, 0, background.getWidth(), 0, 0,
background.getWidth(), background.getHeight() );
// To create a new Texture from the Bitmap:
Texture newTexture = new Texture( image, useAlpha );
// Then to replace an existing texture with the new one you created:
TextureManager.getInstance().replaceTexture( textureID, newTexture );