Editing png file makes background opaque

[Andrus]

png icon appears in Silverlight application toolbar with transparent
backgound.

After making any chages to png file using Windows Vista paint transparency
is lost:
image appers with white opaque backgound.
For to keep original transparent backgound ?

 

[Peter Duniho]

png icon appears in Silverlight application toolbar with transparent
backgound.

After making any chages to png file using Windows Vista paint
transparency is lost:
image appers with white opaque backgound.
For to keep original transparent backgound ?

If you don't show the code you're using, it's not possible to suggest a
way to fix the code.

Obviously, you've either changed the image format so that it doesn't
support transparency, or you've somehow overwritten the alpha channel in
the process of modifying the image. But beyond that, what change is
required for the code you've got, no one can say for sure.

If you want a good answer, you should post a question with enough
information for people to know what your code is doing. Just knowing the
symptoms isn't enough.

Pete

 

[Andrus]

Pete,

Obviously, you've either changed the image format so that it doesn't
support transparency, or you've somehow overwritten the alpha channel in
the process of modifying the image. But beyond that, what change is
required for the code you've got, no one can say for sure.

If you want a good answer, you should post a question with enough
information for people to know what your code is doing. Just knowing the
symptoms isn't enough.

I havent written any line of code. Image (toolbar save, open etc button) is
referenced from SL xaml file.
Steps to reproduce are simple:

1. Open png icon having transparent backgound in Windows Visa using Paint.
2. Change one pixel, save file.
3. Run application which uses this.

Observed:

Icon background transparency is lost: background color becomes white,
looking ugly.

Andrus.

 

[Jeff Johnson]

1. Open png icon having transparent backgound in Windows Visa using Paint.
2. Change one pixel, save file.
3. Run application which uses this.

Observed:

Icon background transparency is lost: background color becomes white,
looking ugly.

Solution: DON'T use Windows Paint; it doesn't support transparency. Go get
Paint.NET; it's free.

 

[Peter Duniho]

I havent written any line of code.

Ah. Well, then you seem to have posted your question in the wrong
newsgroup.