NSIS/Examples/one-section.nsi

# This example demonstrates how to control section selection.
# It allows only one of the four optional section to be
# selected at any given time.
#
# Please note that the initial value will not be what you expect
# it to be if you are are using InstType because InstType is taken
# into consideration after the .onInit, where the initial state is
# set, executes.
# To use this code with InstType you will either have to specify
# you first InstType to match the initial value you set in .onInit
# (only StrCpy $1 ${sec1} is important in this case because the
# other set the section and that will be done by InstType), or set
# the initial section selection from .onSelChange when it is called
# for the first time.

Name example
OutFile one-section.exe

ComponentText "please choose just one but the default"

# defines SF_*, SECTION_OFF and some macros
!include Sections.nsh

Section !Required
	SectionIn RO
SectionEnd

Section "optional #1" sec1
SectionEnd

Section "optional #2" sec2
SectionEnd

Section "optional #3" sec3
SectionEnd

Section "optional #4" sec4
SectionEnd

Function .onInit
	Push $0

	StrCpy $1 ${sec1} ; Gotta remember which section we are at now...
	SectionGetFlags ${sec1} $0
	IntOp $0 $0 | ${SF_SELECTED}
	SectionSetFlags ${sec1} $0
	# !insertmacro SelectSection ${sec1}

	SectionGetFlags ${sec2} $0
	IntOp $0 $0 & ${SECTION_OFF}
	SectionSetFlags ${sec2} $0
	# !insertmacro UnselectSection ${sec2}

	SectionGetFlags ${sec3} $0
	IntOp $0 $0 & ${SECTION_OFF}
	SectionSetFlags ${sec3} $0
	# !insertmacro UnselectSection ${sec3}

	SectionGetFlags ${sec4} $0
	IntOp $0 $0 & ${SECTION_OFF}
	SectionSetFlags ${sec4} $0
	# !insertmacro UnselectSection ${sec4}

	Pop $0
FunctionEnd

Function .onSelChange
	Push $0

	; Turn off old selected section
	SectionGetFlags $1 $0
	IntOp $0 $0 & ${SECTION_OFF}
	SectionSetFlags $1 $0
	# !insertmacro UnselectSection $1

	; Now remember the current selection
	Push $2
	StrCpy $2 $1

	SectionGetFlags ${sec1} $0
	IntOp $0 $0 & ${SF_SELECTED}
	IntCmp $0 ${SF_SELECTED} 0 +2 +2
		StrCpy $1 ${sec1}
	SectionGetFlags ${sec2} $0
	IntOp $0 $0 & ${SF_SELECTED}
	IntCmp $0 ${SF_SELECTED} 0 +2 +2
		StrCpy $1 ${sec2}
	SectionGetFlags ${sec3} $0
	IntOp $0 $0 & ${SF_SELECTED}
	IntCmp $0 ${SF_SELECTED} 0 +2 +2
		StrCpy $1 ${sec3}
	SectionGetFlags ${sec4} $0
	IntOp $0 $0 & ${SF_SELECTED}
	IntCmp $0 ${SF_SELECTED} 0 +2 +2
		StrCpy $1 ${sec4}

	StrCmp $2 $1 0 +4 ; selection hasn't changed
		SectionGetFlags $1 $0
		IntOp $0 $0 | ${SF_SELECTED}
		SectionSetFlags $1 $0
		# !insertmacro SelectSection $1
	Pop $2
	Pop $0
FunctionEnd