[Fixed] Some text in platform updater/app store, backup/restore, PA.c installer, etc invisible w high contrast Windows theme

The platform's installer and updater/app store as well as the portableapps.com installers are written in NSIS. This is a widely-used open source installer (Firefox, 7-Zip, and lots of other projects use it). You'd need to ask them about full compatibility with high contrast themes.

Side Note: The main bits of the installer, updater, and app store do work with the high contrast theme already, at least on Windows 10. I think I may be able to at least manually detect the high contrast theme and force the white text to black in the affected areas with a bit of work. For note, the affected areas are the welcome/finish pages as well as the headers throughout.

I've changed the subject and labeled this a bug for tracking purposes.

For any developers following along, here is the code to run on a page's show function to force the header to be black text sop it's visible on the forced white background (including a PUSH/POP to ensure we don't dirty any variables):

PUSH $0
FindWindow $0 "#32770" "" $HWNDPARENT
GetDlgItem $0 $HWNDPARENT 1037
SetCtlColors $0 0x000000 0xFFFFFF
GetDlgItem $0 $HWNDPARENT 1038
SetCtlColors $0 0x000000 0xFFFFFF
POP $0

I can't get something similar working on welcome/finish yet even when using the appropriate window handle.

UPDATE2: With the welcome pages in conjunction with MUI2, the following code in a custom show handlers will force black text on a white background:

SetCtlColors $mui.WelcomePage.Title 0x000000 0xFFFFFF
SetCtlColors $mui.WelcomePage.Text 0x000000 0xFFFFFF

And with finish, it's a bit more complicated:

SetCtlColors $mui.FinishPage.Title 0x000000 0xFFFFFF
SetCtlColors $mui.FinishPage.Text 0x000000 0xFFFFFF
${If} $bolHighContrast == "true"
  ;Annoying hack to ensure checkboxes are visible when high contrast is on
  SetCtlColors $mui.Finishpage.Run 0x000000 0x888888
  SetCtlColors $mui.FinishPage.ShowReadme 0x000000 0x888888
${EndIf}

Unfortunately, you can't properly set checkbox fore color. Only the background. So, this is an annoying hack to set the checkbox background to 50% gray. This ensures it's somewhat visible for both the standard white or yellow text as well as the less common black text high contrast themes.

I still can't yet determine high contrast use within NSIS itself but can determine it in the platform. So the platform can pass it along to apps as well as to backup/restore and app store/updater when necessary. The next platform release will set an environment variable called PortableApps.comHighContrast. To pull it into an NSIS variable, define it and then put this in .onInit:

ReadEnvStr $bolHighContrast "PortableApps.comHighContrast"

I'll continue updating as I make more progress.

UPDATE3: I've refined the header hack into an easily-inserted macro that works for both MUI version 1 and 2. Including this macro will let you just call ${PageHeaderHackForHighContrast} in your show function:

!define PageHeaderHackForHighContrast "!insertmacro PageHeaderHackForHighContrast"
!macro PageHeaderHackForHighContrast
	!if ${MUI_SYSVERSION} >= 2
		SetCtlColors $mui.Header.Text 0x000000 0xFFFFFF
		SetCtlColors $mui.Header.SubText 0x000000 0xFFFFFF
	!else
		Push $0
		FindWindow $0 "#32770" "" $HWNDPARENT
		GetDlgItem $0 $HWNDPARENT 1037
		SetCtlColors $0 0x000000 0xFFFFFF
		GetDlgItem $0 $HWNDPARENT 1038
		SetCtlColors $0 0x000000 0xFFFFFF
		Pop $0
	!endif
!macroend

This is fixed and worked around in today's release of the PortableApps.com Installer 3.5.2. The welcome and finish screens as well as the header are forced to black text regardless of Windows' settings to be visible on the background which is locked to white by NSIS itself. There is an issue with the one or two check boxes on the final screen (run, read log, etc) where they will not accept a changed color and will use Windows' colors. In this instance, it will look for an environment variable called PortableApps.comHighContrast and if it is set to true, it will force a gray background behind both checkboxes and text. The next release of the PA.c Platform will set this environment variable automatically based on your Windows theme setting. You can force this mode on by setting that environment variable to true at the Windows level or you can test it by creating a batch file called test.bat or similar next to the PortableApps.comInstaller_3.5.2.paf.exe installer with these lines in it:

Set PortableApps.comHighContrast=true
PortableApps.comInstaller_3.5.2.paf.exe

The above-mentioned changes affect both the PortableApps.com Installer's generation wizard as well as all the app installers it generates. Today's updated apps all use this new installer so should be visible in high contrast now.

I will continue updating the platform for the next release with similar changes to the PA.c App Store/Updater, Backup/Restore utility, and the platform's installer as well. This bug will remain open until then.

The environment variable PortableApps.comHighContrast is now set in the PortableApps.com Platform stable 14.4.2 and later as well as the 15.0 Beta 1 and later releases. This will allow installers and tools that are aware of it (like the PortableApps.com Installer generator and the PA.c Installers themselves) to automatically utilize it to fix checkboxes.

This should all be fixed in the new 15 Beta 2 release of the platform I just posted. I made the fixes to the updater/app store, backup, and restore. The bug will remain open pending stable release.

The above-mentioned fixes have all landed in the stable channel with the 15.0 release.