InstallScopeDlg in Custom Wix UI not working - wix

Question

Hi i have developed an setup with wix and now i need to ask users wether its AllUser or perUser.After a long research i found that InstallScopeDLg can make it possible.But I have added custom UI with my wix and i wasn't able to add InstallScopeDlg with this custom UI in WIX.
<Publish Dialog="LicenseAgreementDlg" Control="Back" Event="NewDialog" Value="WelcomeDlg">1</Publish>
<Publish Dialog="LicenseAgreementDlg" Control="Next" Event="NewDialog" Value="ReadmeDlg" Order="2">LicenseAccepted = "1"</Publish>
<Publish Dialog="MyInstallScopeDlg" Control="Back" Event="NewDialog" Value="LicenseAgreementDlg">1</Publish>
<Publish Dialog="MyInstallScopeDlg" Control="Next" Event="NewDialog" Value="ReadmeDlg" Order="2"></Publish>
<Publish Dialog="ReadmeDlg" Control="Back" Event="NewDialog" Value="LicenseAgreementDlg">1</Publish>
<Publish Dialog="ReadmeDlg" Control="Next" Event="NewDialog" Value="CustomizeDlg" Order="2"></Publish>
and this is my InstallScopeDlg code
<?xml version="1.0" encoding="UTF-8"?><!--
Copyright (c) Microsoft Corporation. All rights reserved.-->
<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi">
<Fragment>
<UI>
<Dialog Id="MyInstallScopeDlg" Width="370" Height="270" Title="!(loc.InstallScopeDlg_Title)" KeepModeless="yes">
<Control Id="BannerBitmap" Type="Bitmap" X="0" Y="0" Width="370" Height="44" TabSkip="no" Text="!(loc.InstallScopeDlgBannerBitmap)" />
<Control Id="BannerLine" Type="Line" X="0" Y="44" Width="370" Height="0" />
<Control Id="BottomLine" Type="Line" X="0" Y="234" Width="370" Height="0" />
<Control Id="Description" Type="Text" X="25" Y="23" Width="280" Height="20" Transparent="yes" NoPrefix="yes" Text="!(loc.InstallScopeDlgDescription)" />
<Control Id="Title" Type="Text" X="15" Y="6" Width="200" Height="15" Transparent="yes" NoPrefix="yes" Text="!(loc.InstallScopeDlgTitle)" />
<Control Id="BothScopes" Type="RadioButtonGroup" X="20" Y="55" Width="330" Height="120" Property="WixAppFolder" Hidden="yes">
<RadioButtonGroup Property="WixAppFolder">
<RadioButton Value="WixPerUserFolder" X="0" Y="0" Width="295" Height="16" Text="!(loc.InstallScopeDlgPerUser)" />
<RadioButton Value="WixPerMachineFolder" X="0" Y="60" Width="295" Height="16" Text="!(loc.InstallScopeDlgPerMachine)" />
</RadioButtonGroup>
<Condition Action="show">Privileged AND (!(wix.WixUISupportPerUser) AND !(wix.WixUISupportPerMachine))</Condition>
</Control>
<Control Id="PerUserDescription" Type="Text" X="33" Y="70" Width="300" Height="36" Hidden="yes" Text="!(loc.InstallScopeDlgPerUserDescription)">
<Condition Action="show">!(wix.WixUISupportPerUser)</Condition>
</Control>
<Control Id="NoPerUserDescription" Type="Text" X="33" Y="70" Width="300" Height="36" Hidden="yes" Text="!(loc.InstallScopeDlgNoPerUserDescription)">
<Condition Action="show">NOT !(wix.WixUISupportPerUser)</Condition>
</Control>
<Control Id="PerMachineDescription" Type="Text" X="33" Y="131" Width="300" Height="36" Hidden="yes" Text="!(loc.InstallScopeDlgPerMachineDescription)">
<Condition Action="show">Privileged</Condition>
</Control>
<Control Id="Back" Type="PushButton" X="180" Y="243" Width="56" Height="17" Text="!(loc.WixUIBack)" />
<Control Id="Next" Type="PushButton" X="236" Y="243" Width="56" Height="17" Default="yes" Text="!(loc.WixUINext)" />
<Control Id="Cancel" Type="PushButton" X="304" Y="243" Width="56" Height="17" Cancel="yes" Text="!(loc.WixUICancel)">
<Publish Event="SpawnDialog" Value="CancelDlg">1</Publish>
</Control>
</Dialog>
</UI>
and for RadioButtonGroup Property="WixAppFolder" in InstallScopeDlg
i have added in product.wxs file
and am getting the error code as
Error 10 The Windows Installer XML variable
!(wix.WixUISupportPerUser) is unknown. Please ensure the variable is
declared on the command line for light.exe, via a WixVariable element,
or inline using the syntax !(wix.WixUISupportPerUser=some value which
doesn't contain parenthesis).

Answer 1

Hence it we need to initially declare its components under the fragment section in your myinstallscopedlg.wxs
<?xml version="1.0" encoding="UTF-8"?><!--
Copyright (c) Microsoft Corporation. All rights reserved.-->
<Wix xmlns="http://schemas.microsoft.com/wix/2006/wi">
<Fragment>
<WixVariable Id="WixUISupportPerUser" Value="1" Overridable="yes" />
<WixVariable Id="WixUISupportPerMachine" Value="1" Overridable="yes" />
<UI>
<Dialog Id="MyInstallScopeDlg" Width="370" Height="270" Title="!(loc.InstallScopeDlg_Title)" KeepModeless="yes">
by doing this this ERROR The Windows Installer XML variable !(wix.WixUISupportPerUser) is unknown. will be solved