Android Question Strange behaivor when rotating image

[TrisectDevelopment]

I'm trying to rotate an image to show direction(0 - 360) but something strange happens.

This is my code:

    Dim rbmp As RSImageProcessing
    Dim finalBitmap As Bitmap

    '** Roter center billedet
    ivCenter.Bitmap = StartCenterBitmap    '** Hent gemt bitmap
    rbmp.Initialize
  
    finalBitmap = ivCenter.Bitmap
    finalBitmap = rbmp.rotateBitmap(finalBitmap, direction)
    ivCenter.Bitmap = finalBitmap

When I start the App i take a copy of the image and put it into StartCenterBitmap so I allways have the same image to start with when I rotate.

But every time I run this code the image change size (scale) and I don't know why.

This is my image. Its a white circle with an arrow showing the direction.
This image is in an ImageView with the size of 330x330

I try to insert this line in my code but with no difference.

finalBitmap = rbmp.scaleBitmap(finalBitmap, 1.3, 1.3)

 

[TrisectDevelopment]

What I'm trying is that the arrow should show the direction.

 

[eurojam]

If you want to do something like a compass or so on, it is easier to use canvas and DrawBitmapRotated.
see this example: https://www.b4x.com/android/forum/threads/catch-the-bouncing-smiley.6442/
or this one: https://www.b4x.com/android/forum/threads/rotating-bitmap.6733/#post-39103

 

[TrisectDevelopment]

Can I have labels and buttons together with what you suggest?

 

[eurojam]

you can combine buttons and labels together with a canvas, but can you specify how you want to combine them. should they rotate too?

 

[TrisectDevelopment]

No I only want my "image" to rotate.
I have not worked with canvas before.

 

[eurojam]

then you should try it.
I used it for a compass like app and it is the best way to do it, don't use image processing for that.

 

[klaus]

Did you have a look at chapter 16.2.2 Drawing rotating bitmaps / RotatingNeedle in the Beginner's Guide?