Livecodebeginner Q&A - Recent questions

How to parse Xml Data in Live code

Mon, 25 Nov 2013 16:39:35 +0000

on mouseUp
   loadPreferences
end mouseUp

command loadPreferences
   local tTree
   put readPreferencesToXMLTree() into tTree
   if tTree is empty then
      exit loadPreferences
   end if
   processPreferencesTree tTree
   revDeleteXMLTree tTree
end loadPreferences

private function readPreferencesToXMLTree
   set the itemDelimiter to slash
   local tPreferencesFile
   put the URL"http://htp2.hitecpoint.in:98/api/blackbox/live/45" into tPreferencesFile
   local tPreferencesData, tResult
   put tPreferencesFile into tPreferencesData
   put the result into tResult
   if tResult is not empty then
      answer error "Failed to read preferences file at location: " & tPreferencesFile
      return empty
   end if
   local tTree
   put revCreateXMLTree(tPreferencesData, false, true, false) into tTree
   if tTree is not an integer then
      answer error "Failed to process preferences file with error: " & tTree
      return empty
   end if
   return tTree
end readPreferencesToXMLTree

private command processPreferencesTree pTree
  local tPosts
   put revXMLChildNames(pTree, "ArrayOfLiveStatus/LiveStatus", return, "Location", true) into tPosts
   local tListOfNames
   repeat for each line tName in tPosts
      put revXMLNodeContents(pTree, "ArrayOfLiveStatus/LiveStatus" & tName) & return after tListOfNames
   end repeat
   delete the last char of tListOfNames
   local tOutput
   put tListOfNames after tOutput
   set the text of field "NameList" to tOutput
end processPreferencesTree

I am using Livecode software.I am accessing web api "http://htp2.hitecpoint.in:98/api/blackbox/live/45" which return a xml data.I want to parse location node but I always get a error"xmlerr, can't find element".What I am doing wrong please help.

Where in the US can I order Programming LiveCode for the Real Beginner?

Tue, 12 Nov 2013 12:16:05 +0000

Where in the US can I order Programming LiveCode for the Real Beginner?

function Spaces doesn't work

Thu, 13 Jun 2013 00:40:11 +0000

p 225, bottom:

as it is, the function doesn't work, because the repeat argument tries to divide a number by a string

it could be corrected by:

put " " into mySpace

put the length of mySpace into mySpaceLength

repeat max(1,trunc(theAmount/mySpaceLength) + 1) -- I would use "trunc" rather than "round" here

or

repeat max(1,(theAmount div mySpaceLength) + 1)

PS: according to my test, this function is about 20 times faster than the second one, top of p. 226

File signatures for Mac

Tue, 11 Jun 2013 19:31:17 +0000

p. 201, second paragraph: (Mac OS 10 standalones) The document type can be any code you like [...]

If you want a really unique signature (creator code) for your application's files, see indirections at:

https://developer.apple.com/support/mac/creator-code-registration.html

(the URL given in the dictionary for fileType doesn't work any more)

stack's password (p. 200)

Tue, 11 Jun 2013 18:21:10 +0000

p. 200, first paragraph:

a footnote indicating that it is neither possible to set password for stacks, nor to use password protected stacks, with the community edition of LC, would be useful in the next edition.

Replacing crlf by cr when importing from URL

Mon, 10 Jun 2013 22:32:21 +0000

p. 177

You suggest to replace crlf with cr after reading a textfile from an URL. However, in the dictionary, a note specifies:

Likewise, if you put data into a fileURL or get data from it, end-of-line translation is performed, but not if you put data into or get data from a binfileURL.

Is this automatic translation really limited to local files ? Or is your replace statement just a precaution ?

Are scripts available for download?

Fri, 07 Jun 2013 14:49:36 +0000

Are the scripts in the book available for download?

answer file: how to get the arabic name of a file

Tue, 04 Jun 2013 18:08:46 +0000

p. 157

(Mac OS 10.8) I have an UTF8 file created with TextEdit called "ثسسشه.txt" in the answer file dialog (it's actually "txt.ثسسشه" on the desktop).

Answer file returns "/Users/jhausser/Desktop/?????.txt" and of course my script doesn't find the file to read it.

Except changing the file name manually to something more occidental on the desktop, I didn't find a simple way to deal with this problem. Should I use embedded applescript instead of answer file ?

It's probably an important question for people not using latin characters.

realizable window ?

Mon, 03 Jun 2013 20:07:51 +0000

p 151, lines 2 and 3

"realizable"... I guess it should have been "resizable". Damned automatic spell checker !

replace "finally" by "default" in the switch statements

Mon, 03 Jun 2013 19:12:14 +0000

p. 144, example:

"finally" cannot be used in a switch statement, it is reserved for the "try" procedure. Use "default" (without quotes) instead, or you'll get the error:

compilation error at line nn (switch: bad 'case' condition) near "finally", char 1

Not necessary to round the value returned by scrollbarDrag

Mon, 03 Jun 2013 13:21:15 +0000

p. 124, bottom:

It seems that the rounding is not necessary, because scrollbarDrag transmits an integer as long as you don't define a numberformat (or value format depending of how you did set the preferences) in the slider's inspector. To check it, just create a slider with 0 as startValue and 1 as endValue. Don't fill the numberFormat (or, for an equivalent result, set it to 0). You can made the slider as long as you want. Set the handler:

on scrollbarDrag theValue

put theValue into fld 1

end scrollbarDrag

When you drag the slider "thumb", field 1 will contain 0 for any position above (or left) to the middle point of the slider, 1 for any position below or right to this point.

Now, if you go back to the inspector and set the numberformat to, say, "0.000", the field will show any value between 0.000 and 1.000, depending on the slider thumb position.

I checked it with LC 5.5.4 and 6 - but if I remember well, the introduction of the numberFormat for scrollbars is relatively recent, this part of the book was probably written with an earlier version (I didn't keep older versions and cannot check it).

when to change the name of the stack to revSelected Object

Sat, 01 Jun 2013 12:19:18 +0000

page 106

If one change the name of a new stack to anything starting with "rev", this stack will be considered as a plugin... and most of the items of the object menu will be desactived - e.g. it would be impossible to open the card script or the card inspector.

So in the example given it is advisable to set ALL the scripts of the stack and its components, including the card script, BEFORE setting the name of the stack to "revSelected Object".

button's mouseUp default handler

Fri, 31 May 2013 12:29:00 +0000

p. 99, end of first paragraph about backgrounds. "If the script of a button is empty, the group won't receive a mouseUp message"

Not exactly true: Buttons are created with an empty mouseUp handler:

on mouseUp

end mouseUp

which actually blocks the message. But if you remove this script and click "apply", or create a new script without a mouseUp handler, the mouseUp message will be passed along the message path normally.

But be careful! if you re-open the script of a button with an empty script, the empty mouseUp handler will be recreated ! To be sure that your button remains functionally "scriptless" (what can be useful in some circumstances) you have either to correct the default script with a "pass mouseUp" statement or to create a dummy scipt like

command doAbsolutelyNothing

end doAbsolutelyNothing

the visible is the inverse of the invisible

Fri, 31 May 2013 11:39:01 +0000

p 93, under the example

instead of "then you will see true,true,false,false"

read "then you will see true,false,false,true"

Put and get URL

Wed, 29 May 2013 11:50:08 +0000

p. 73, table 10, MS Windows' column

replace:

put myText into url\

"file:C:/test.txt"

with:

put URL "file:C/test.txt\

into myText

Location and Availability of Declared Variables

Tue, 28 May 2013 19:18:16 +0000

p. 61, next to last paragraph. "When x contains x, function foo() puts 1 into x, but..."

should be "When x contains 1, function foo() puts 2 into x, but..."

selectedChunk example

Tue, 28 May 2013 14:01:59 +0000

p. 55, example 2: Replace "Put the selectedChunk the selectedChunk into fld Position" by "Put the selectedChunk into fld Position"

firstFunction parentheses forgotten

Tue, 28 May 2013 11:19:09 +0000

p 47, 3rd example, second line: "put firstFunction into fld i" should be "put firstFunction() into fld i". If the parentheses are absent, firstFunction is interpreted as a string.

"on" versus "command"

Tue, 28 May 2013 10:49:16 +0000

p. 44, paragraph 2: Replace "A openStack handler woulde be preceded by the "command" keyword" by "A openStack handler woulde be preceded by the "on" keyword".

the second line of the message box

Tue, 28 May 2013 10:44:56 +0000

p 25, paragraph 5: I would suggest to replace "the second line of the message box" and "the bottom line of the message box" by "the bottom part of the message box", because it actually has more than one line (e.g. when you type something like "put the script of btn "Bx")

the min function

Tue, 28 May 2013 10:33:45 +0000

p. 33, table 1, first line: put min(1,2,3,4) returns 1, not 0

how to send corrections (plural)

Mon, 27 May 2013 19:40:19 +0000

After a quick general browsing (congrats! the book is clearly written and seems very useful not only for real beginners but for old LC users as well !) I just started a more detailed reading - and, as everybody who published books could confirm, it is strictly impossible to publish a book without some bugs and typos. So I found some of them. And as I'm sure you'll have a second edition soon (14 copies left, you told us), it's worthwile to report them.

My question: do you prefer a list of what I found when I'll be through the entire book or a case-by-case notification ? And if you prefer the list, how and where to send it ?

I have a comment, which you should know about.

Sun, 26 May 2013 14:46:51 +0000

I have found a mistake in the text of the book. I might also have some general remarks.

Will there be a Spanish/French/German transation?

Sun, 26 May 2013 14:43:00 +0000

I'm sure that this book would be a big sucess if it were translated into [enter your language here]! Can you provide a translation?

Can I get a discount?

Sun, 26 May 2013 02:52:43 +0000

Can I get a discount?

Does the book apply to LiveCode 6.0 and later?

Sun, 26 May 2013 02:51:15 +0000

I have LiveCode 4.6. I guess your book is only for LiveCode 6 and later?

What if the book doesn't arrive?

Sun, 26 May 2013 02:49:50 +0000

I ordered my book 6 weeks ago and it hasn't arrived yet. What should I do?

Can I reserve a copy of the book?

Sun, 26 May 2013 00:45:20 +0000

I'd like to buy the book but not just yet. Can I order or reserve a copy now and pay for it later?

Can you please ship it after I come back from holidays?

Sun, 26 May 2013 00:35:19 +0000

I may not be at home when the book arrives and I have no neighbours who check the mail for me. Can you send the book another time if I buy it now?

Can you please, please, please ship it more quickly?

Sat, 25 May 2013 22:12:02 +0000

I have ordered the book and I need it when I go for holidays/go hiking/give a class to students/have an exam/have a deadline/do something else. You wrote on the website and in your e-mails that delivery can take up to 4 weeks. Can you pretty please send it more quickly?

When will I receive the book?

Sat, 25 May 2013 22:08:33 +0000

I have purchased the book a few days ago. When will I get it? Can you give an ETA?

Will an electronic book be made available?

Sat, 25 May 2013 22:06:37 +0000

Will Programming LiveCode for the Real Beginner become available as an e-book?

Have you read the book Programming LiveCode for the Real Beginner?

Tue, 07 May 2013 17:35:09 +0000

To make sure that this site works correctly and also out of curiosity, I ask you this questions.