1) Create a new stack by selecting 'New Mainstack' from the file menu

2) Open the 'Stack Inspector' from the menubar

3) I've given my stack a name and also a title

4) Set the with and height of the stack to 320 * 460 (iPhone)

5) Prevent the stack from being resized

Our stack is now setup and we can move one to coding this example.

Mobile deployment imposes strict controls over what you can and cannot access. Each application in mobile is stored in its own 'sandbox' folder (referred to as the home folder.) An application is free to read and write files within this folder and its descendants, but is not allowed to access anything outside of this.

When an application is installed on a phone (or in the simulator) a number of initial folders are created for use by the application. You can locate the paths to these folders using the specialFolderPath() function.

home – the (unique) folder containing the application bundle and its associated data and folders.

documents – the folder in which the application should store any document data (this folder is backed up by iTunes on sync)

cache – the folder in which the application should store any transient data that needs to be preserved between launches (this folder is not backed up by iTunes on sync)

temporary – the folder in which the application should store any temporary data that is not needed between launches (this folder is not backed up by iTunes on sync)

engine – the folder containing the built standalone engine (i.e. the bundle). This is useful for constructing paths to resources that have been copied into the bundle at build time.

You can test this entering the following line of LiveCode into the message box:

put specialFolderPath("documents")

I am on a Mac so this will return the full path to my default Documents folder:

/Users/ben/Documents

This will be different for every user. It will also change depending on your platform. LiveCode will return the default location for documents on whichever platform your application runs on.

You can reference files in 1 of two ways:

1) Build the full path to your file every time you want to access it.

2) Set the folder that LiveCode performs all File and Folder operation within (default)

set the defaultFolder to specialFolderPath("documents")

Now, whenever you look to perform a Read or Write it will be done relative to the documents folder.

1) Drag on a new button. Name it "Write"

2) Drag on a second button. Name it "Read"

3) Drag on a label. Name it "write" and add some text to its contents

4) Drag on a label. Name it "read". I've added "No Data" to its contents just so that I can see it

Add the following script to the "Write" button:

on mouseUp
	set the defaultFolder to specialFolderPath("documents")
	put field "write" into URL ("file:test.txt")
end mouseUp

There are various ways to read and write to files in LiveCode. You can 'Open' a file and then 'Read' or 'Write'. For smaller files I prefer to use the URL command. It allows us to simply 'Put' our data in the file. If the file you specified doesn't exist LiveCode will create it for you.

If you are writing binary data to your files your should use "binfile:" instead of "file:" before your filename.

Add the following script to your "Read" button:

on mouseUp
	set the defaultFolder to specialFolderPath("documents")
	put URL ("file:test.txt") into field "read"
end mouseUp