This example shows how to navigate a list of items.
Complete with wrap-around:
Strict
' Initialise a TList called mylist
' This is used to hold a list of strings
Global mylist:TList=New TList
' add some items to mylist
mylist.AddLast "Apple"
mylist.AddLast "Banana"
mylist.AddLast "Pear"
mylist.AddLast "Blackberry"
mylist.AddLast "Peach"
mylist.AddLast "Mango"
' Initialise a TLink called link
' Set it to point to the first item in mylist
Global link:TLink=mylist.FirstLink()
' store the string from the first item into selected$
Global selected$=String(link.Value())
' open a small graphic window
AppTitle = "Lists - Next/Previous example"
Graphics 300,180,0,30|SOFTSYNC
SetClsColor $aa,$aa,$aa
Repeat
' if user presses ESCAPE break out of the loop
If KeyHit(KEY_ESCAPE) Exit
' if user presses DOWN ARROW move to next item in list
If KeyHit(KEY_DOWN)
link=link.NextLink()
If link=Null link=mylist.FirstLink()
selected$=String(link.Value())
EndIf
' if user presses UP ARROW move to previous item in list
If KeyHit(KEY_UP)
link=link.PrevLink()
If link=Null link=mylist.LastLink()
selected$=String(link.Value())
EndIf
' If DEL pressed remove selected item
' Now point to the first item in the remaining list
' If the list is empty exit from the loop
If KeyHit(KEY_DELETE)
mylist.Remove selected$
link=mylist.FirstLink()
If link=Null Exit
selected$=String(link.Value())
EndIf
' if user presses RETURN key show item selected
If KeyHit(KEY_RETURN)
Notify "Your choice is "+selected$
EndIf
' show list and highlight the 'selected' item
Cls
SetColor $88,$44,$00
DrawText "Cursors UP/DOWN to select item",10,10
DrawText "RETURN to confirm selection",10,24
Local y=55
For Local l$=EachIn mylist
SetColor $22,$22,$22
If l$=selected$ SetColor $ff,$ff,$ff
DrawText l$,40,y
y:+16
Next
Flip
FlushMem
Forever
End