Add default file extension configuration

[Lyqst]

Closes #1304
There was already a config option for this, called setSaveAsFileExtension, but it wasn't exposed in the configuration panel. I've changed it to defaultFileExtension so it has a clearer name, and added it to the general options tab in the configuration panel as a ComboBox.

[veracioux]

@Lyqst Thank you for your contribution. I didn't test the feature in detail, but I have a few small criticisms:

• When I restart flameshot, the spin box should load the extension from the config file. Currently it displays an empty extension every time.
• I don't think you should change existing option names. This will break people's existing configs. At least until we implement a way for people to resolve configs between flameshot versions (I'm not aware of any ongoing discussions about this). I agree that setSaveAsFileExtension is a poorly chosen name.
• I think the "Preferred save file extension:" text would look better if you put it inside the "Save Path" group (to make it indented).

[Lyqst]

@veracioux Thanks for your comments!

When I restart flameshot, the spin box should load the extension from the config file. Currently it displays an empty extension every time.

Not sure what you mean with spin box, but when I test these changes on my machine (Manjaro), it loads whatever option has been previously saved. Maybe I'm missing something here, please let me know.

I don't think you should change existing option names. This will break people's existing configs. At least until we implement a way for people to resolve configs between flameshot versions (I'm not aware of any ongoing discussions about this). I agree that setSaveAsFileExtension is a poorly chosen name.

I see your point, makes total sense to keep compatibility with existing configs. I'll change this back to the old name.
On a side note, the previous config was only working with extensions beginning with . (.png instead of png), so to keep full compatibility I'll append the . to each options in the ComboBox.

I think the "Preferred save file extension:" text would look better if you put it inside the "Save Path" group (to make it indented).

I agree, I'll make this change.

[veracioux]

@Lyqst I meant to say combo box instead of spin box. Confused them because they look similar. And it does actually load the extension from the config. But my config contained .png instead of png so the combo box displayed it as an empty string.

While you are at it, would you mind adding a ValueHandler that forces the setSaveAsFileExtension's value to be a valid image mime-type (plus the . at the beginning)? (see src/utils/valuehandler.h) This way, the user will get a config error if the image format is unsupported.

[Lyqst]

Hi @veracioux, I've implemented the ValueHandler, with the added value that the config will now accept image formats with or without the ..

[veracioux]

@Lyqst Thanks for the changes. I hope the ValueHandler was intuitive enough to implement. That class is a recent addition to flameshot.

There are a few problems though:

• When I select an extension in the GUI, it is saved to the config without the ., but that is recognized by the value handler as an error
• When I try to take a screenshot and save it, the file extension does not match the one I configured

[Lyqst]

@veracioux I think it was intuitive enough! Only thing I wasn't clear at first was to set the type of the handler in the recognizedGeneralOptions map, but figured it out after it a bit of digging.

When I select an extension in the GUI, it is saved to the config without the ., but that is recognized by the value handler as an error

It was an issue in the check function, it was comparing against the raw val, instead of the extension variable with the . removed (if it had one).

When I try to take a screenshot and save it, the file extension does not match the one I configured

Had to pass the format to the properScreenshotPath call so it could use it to generate the filename.

[veracioux]

@Lyqst Working like a charm!

@veracioux I think it was intuitive enough! Only thing I wasn't clear at first was to set the type of the handler in the recognizedGeneralOptions map, but figured it out after it a bit of digging.

Thanks for the feedback. I hope this will be crystal clear to new contributors once we make a developer documentation.

If it's not too much of a bother, could you just place the "Preferred save file extension" along with its combo box into the "Save Path" group for better indentation? Just for aesthetic reasons.

Other than that, if you have nothing to add and if the checks pass, I can get this merged.

[Lyqst]

@veracioux done!

[veracioux]

@Lyqst Perfect! Thank you very much for your contribution.