Question

I am making the following call in my blackberry application (API ver 4.5)…

public void annotate(String msg, EncodedImage ei)
{
  Bitmap bitmap = ei.getBitmap();

  Graphics g = new Graphics(bitmap);
  g.drawText(msg,0,0);
}

And I keep getting an IllegalArgumentException when I instantiate the Graphics object. Looking at the documentation for Graphics is confusing as it leaves many things unstated.

What does it mean by ‘default type of the device’?
How do you know if the type of ‘bitmap’ is not supported? Does this mean that there are different types of bitmaps? Can different encodedImages generate different types of bitmaps?

Is there another way to add my string to the associated encoded image?

public Graphics(Bitmap bitmap)

Constructs a Graphics object for drawing to a bitmap.

Parameters:

bitmap – Bitmap to draw into. Must be Bitmap.COLUMNWISE_MONOCHROME or the default type of the device.

Throws:

IllegalArgumentException – If the type of ‘bitmap’ is not supported, or the bitmap is readonly.

Answer 1

Are you sure that your Bitmap is mutable? You can’t create Graphics objects from immutable Bitmaps. That is one cause of an IllegalArgumentException. You can set the decode mode for your EncodedImage (EncodeImage.setDecodeMode). There are different modes that allow you to specify whether the file is native or readonly…along with other modes that can be combined.

The size of the bitmap might be another IllegalArgumentException. Of course, this is relevant to the target device.