Text boxes and sliders

BlitzMax Forums/BlitzMax Beginners Area/Text boxes and sliders

Marco A G Pinto

(Posted 2012) [#1]

Hello!!!

I want to associate sliders to text boxes and use special properties.

We can use the sliders to select values between 0 and 255.

How do I limit the number of characters in the text box to 3 digits and prevent non numeric characters?

Here is how I am creating one of the sliders and associate a text box to it:

'   Place the main panel which will have most of the gadgets inside
	Global panel:TGadget=CreatePanel(21,97-4-2+8-6-3,450+20-20,240-20-20-20-40+6+3+2,window,PANEL_GROUP,"NORMAL TRAINER")
'	SetGadgetLayout panel, EDGE_ALIGNED, EDGE_ALIGNED, EDGE_ALIGNED, EDGE_ALIGNED
'	SetGadgetColor(panel,160,255,160)
'   Create sliders
'	LIVES1
    Global lives1_slider = CreateSlider:TGadget(80-10-2,10,20,20,panel:TGadget,SLIDER_STEPPER)
	SetSliderRange(lives1_slider,0,255)
	SetSliderValue(lives1_slider,lives1)
	Global status_text_field_lives1=CreateTextField:TGadget(80-40-10,10+1,35,16+4,panel)
	SetGadgetText(status_text_field_lives1,lives1)
	CreateLabel("LIVES1",80-10-2+10+10+5,20-5-2,40,15,panel)

Any ideas?

Thanks!

Kind regards,
>Marco A.G.Pinto
-------------------

Midimaster

(Posted 2012) [#2]

you have two possibilities. first is to check it.

1. After the textbox is firing an event, because the user is pressing a key. This has tha advantage of checking characters and digits in the same function:

	Function Event (EventQuelle:Object)
		Local tmpGadget:TGadget = TGadget(EventQuelle)
		If tmpGadget 
			If  GadgetClass(tmpGadget) = GADGET_TEXTFIELD
					CheckInhalt  3, tmpGadget			
	.....
	


	Function CheckInhalt(Anzahl% , TextField:TGadget )
		Local Zeichen$, i% , Erlaubt$ , Inhalt$
		
		Inhalt=GadgetText(TextField)
		Inhalt=Upper(Inhalt)
		Erlaubt="1234567890"

		For i=1 To Len(Inhalt)			
			zeichen=Mid(Inhalt,i,1)
			If Erlaubt.Find(Zeichen)=-1 Then
				PrintOut "verboten " + zeichen
				Inhalt=Left(Inhalt,i-1)+Mid(Inhalt,i+1,-1)
			EndIf
		Next
		Inhalt=Left(Inhalt,Anzahl)
		SetGadgetText TextField,Inhalt
	End Function

2. A second possibility is to use the build-in-pre-check of MaxGui.This only can check charakters, but you can add a digit checking too:

This adds a callback function to the maxgui, which is called erery time when a key is pressed in this textgadget. Depending on the RETURN-vakue of the function MaxGui add the new character or not:

You need to let through also the BACKSPACE, DELETE, CURSORs, etc... keys too!

TextField=CreateTextField(0,0,100,60,Mother,0)
SetGadgetFilter TextField, ZahlenFilter

Function ZahlenFilter%(event:TEvent,context:Object)
	Local Key%=event.data
	Select event.id
		Case EVENT_KEYDOWN
			Select Key
				Case 8,32,37,38,39,40,46,45
					Return 1
				Case 48,49,50,51,52,53,54,55,56,57
					Return 1
				Default
					Return 0
			End Select
		Case EVENT_KEYCHAR
			Select Key
				Case 48,49,50,51,52,53,54,55,56,57
					Return 1
				Case 32,45
					Return 1
				Default
					Return 0
			End Select
	End Select
End Function

if you want you can add a counting of digits, which would return 0 if they are is already to many.