Creating a Password Field
Learn how to create a password entry field using a a custom font and start using font. You can download the PasswordEntry.ttf font here.
The Goal
Password entry fields require that you mask the text in the field so it cannot be read or copied from the field. The easiest way to mask the text in a field is to use a font that draws all characters as bullets. This allows you to still access the text property of the field in order to get the actual password but the user only sees bullets.
Loading The Font
LiveCode enables a developer to load a font at runtime using start using font. The code below shows how you can load the PasswordEntry.ttf font file that resides in the same directory as a stack file.
on preOpenStack
set the itemdelimiter to slash
put the effective filename of this stack into theFontFile
delete the last item of theFontFile
put theFontFile & "/PasswordEntry.ttf" into theFontFile
start using font file theFontFile
put the result into theError
if theError is not empty then
answer "Error loading password font:" && theError & "."
end if
end preOpenStackAfter adding this code to your card script, trigger it so that the font is loaded into the LiveCode IDE. If the stack is the topmost stack then run this in the message box:
dispatch "preOpenStack" to this card of this stackAssign Font To Field
Now that you are loading the font you can assign it as the textFont of the password field. The name of the font is PasswordEntry. Select the font from the mneu or manually type PasswordEntry into the Font field using the Property Inspector.
Filter Input and Don't Allow Copy/Cut
The last thing to do is write some code that prohibits cut/copy and filters input. This example allows characters between ascii numbers 33 and 126. Just put the code in the script of the password field.
on rawKeyDown pKeyCode
## Keypad keycodes for 0 - 9
put "65456,65457,65458,65459,65460,65461,65462,65463,65464,65465" into theKeyPadKeyCodes
put "65361,65362,65363,65364" into theArrowKeys
put 65288 into theDeleteKeyCode
put 65535 into theBackspaceKeyCode
put 65289 into theTabKeyCode
put 65293 into theReturnKeyCode
put "65505,65513" into theModifierKeys # shift, alt/option,
put 97 into theAKeyCode
put 118 into thePasteKey
put the commandkey is "up" and the shiftkey is "up" and the altkey is "up" into noModifiersAreDown
put the commandkey is "down" and the shiftkey is "up" and the altkey is "up" into commandModifierIsDown
set the wholematches to true
if pKeyCode is among the items of theArrowKeys then
pass rawKeyDown
else if noModifiersAreDown and pKeyCode is among the items of theKeyPadKeyCodes then
pass rawkeydown
else if noModifiersAreDown and (pKeyCode is theTabKeyCode or pKeyCode is theReturnKeyCode) then
pass rawkeydown
else if pKeyCode is thePasteKey and commandModifierIsDown then ## paste
pass rawkeydown
else if pKeyCode is theAKeyCode and commandModifierIsDown then ## select all
pass rawkeydown
else if (pKeyCode >= 33 and pKeyCode <= 126 or \
pKeyCode is theDeleteKeyCode or pKeyCode is theBackspaceKeyCode) and \
(the commandkey is "up") then
pass rawkeydown
else if pKeyCode is not among the items of theModifierKeys then ## Shiftkey sends msg on Windows, not Mac
beep
end if
end rawKeyDown
on cutKey
end cutKey
on copyKey
end copyKey
Hello,
Thank you for supplying the sample code and link to the .ttf. There is just one small error in your initial code and it should be updated for others:
http://docs.runrev.com/Command/revFontLoad --> "If the font was loaded successfully, the revFontLoad command puts empty into the result. If the font failed to load or invalid parameters were given, the result will contain an error string. "
The error handling code needs to be changed from: "if theError is empty then" to "if theError is not empty then"
The final thing to adjust is that adding "Password Entry" will not work (the default / previous font will be selected after moving away from the property).
I did this to make it work:
1) Added the correct code above (Selecting Object -> Stack Script) and copy-paste your code
2) Ran the code (green button)
3) No font visible?
4) Saved the stack / card and exit.
5) Open (no error thrown by the loading of font), then I could select "PasswordEntry" from the text field.
Thanks & regards
IA