Adobe InDesign CS5 : Creating and Running Scripts

1. Writing simple scripts

The following three scripts, taken from Adobe's InDesign script examples, do the same thing in JavaScript, AppleScript, and VBA — they rotate an EPS graphic and its frame.

Type the lines that follow this paragraph exactly as they're written for the scripting language you've chosen. Type a return character at the end of each line. Note also the use of straight quotation marks instead of curly typesetter's quotes (the script editor does this for you). Be very careful when you type the text: Typos are script killers.

1.1. JavaScript

var myL ink, myEPs, myFrame;
if(app.documents.length != 0){
 if(app.activeDocument.links.length != 0){
  for(var myLinkCounter = 0; myLinkCounter < ⌝
     app.activeDocument.links.length; myLinkCounter ++){
   myLink = app.activeDocument.links.item(myLinkCounter);
   if(myLink.linkType == "EPS"){
    myEPS = myLink.parent;
    myFrame = myEPS.parent;
    myFrame.rotationAngle = 30;
   }
  }
 }
}

This script first searches through all the items on the page and checks whether any are EPS; if so, it sets the rotation of the item to 30. (Thanks to Adobe's InDesign scripting guru, Olav Martin Kvern, for developing the JavaScript code example.) Note the sequence of actions: First you verify that there is a nonempty document open, and then you check the content type of objects. For those objects of the EPS type, you activate the frame and then apply the rotation to that frame. JavaScripts require you to set your own variables (the var statements) that define what the object is. (Here, myLink is used for each object, myEPS is the object that contains the EPS attribute, and myFrame is the parent frame containing the EPS graphic.) You work with those variables to see what their attributes are and then change those attributes.

If you're in an adventurous mood, try substituting the statement myFrame.rotationAngle = 30; in the preceding script with each of the following statements:

myFrame.shearAngle = 30;
myFrame.verticalScale = 200;

If you want to get really fancy, combine all the myFrame. statements into a single script so that you can use the script to make all the changes at one time.

1.2. AppleScript

tell application "Adobe InDesign CS5"
 activate
 set myPageItems to {EPS, oval, rectangle, polygon}
 set mySelection to selection
 if class of item 1 of mySelection is in myPageItems ⌝
    and (count mySelection) > 0 then
  if class of item 1 of mySelection is EPS then
   set myFrame to parent of mySelection
  else
   set myFrame to item 1 of mySelection
  end if
  set rotation angle of myFrame to 30
 end if
end tell

If you're feeling daring, try substituting the statement set rotation angle of myFrame to 30 in the preceding script with each of the following statements:

set shear angle of myFrame to 30
set vertical scale of myFrame to 200

Here again, you can get fancy by combining all the set statements into a single script so that you can use the script to make all the changes at one time.

1.3. VBA

Dim myInDesign As InDesign.Application
Set myInDesign = CreateObject("InDesign.Application.CS5")
Set mySelection = myInDesign.Selection
If TypeName(mySelection.Item(1)) = "EPS" Then
 mySelection.Parent.RotationAngle = 30
Else
 mySelection.RotationAngle = 30
End If

You might satisfy your adventurous streak by substituting the statement mySelection. RotationAngle = 30 in the preceding script with each of the following statements:

set the color of the current box to "Blue"
set the shade of the current box to 50
set the width of the frame of the current box to 10
set the box shape of the current box to ovular

Go to town if you want: Combine all the set statements into a single script so that you can use the script to make all the changes simultaneously.

2. Labeling items

As you can see from the examples in the previous section, scripts often refer to items by their type and location in the document. But there's another way to refer to objects that makes sure you can select an item precisely: You can label, or name, an item. You do so in the Script Label panel (choose Window => Utilities => Script Label). The process is easy: Select the object and then type a name in the panel. That's it!

When writing scripts, you refer to the labeled object as follows. In these examples, the label is TargetFrame, and don't worry that the samples seem to do different things — they in fact are unrelated examples, not variations of the same command.

2.1. JavaScript

with(app.docum ents.item(0).pages.item(0)){
 myTargetFrame = textFrames.item("myTargetFrame");
}

2.2. AppleScript

select (page item 1 of page 1 of myTargetDocument whose ⌝
label is "TargetFrame")

2.3. VBA

Set myAsset = myLibrary.Assets.Item("TargetFrame")

3. Writing conditio nal scripts

Some scripts simply automate a set of tasks in documents whose content is predictable. But more often than not, documents differ, so you need conditional statements to evaluate certain things to see whether they are true before applying a script's actions. Otherwise, you get an error message when something turns out not to be true. As a simple example, a script that does a search and replace needs to have a document open and a frame selected. If no frame is selected, the script won't know what to search, and the user gets an error message.

The same issue arises for repeated series of actions, where you want the script to do something for all occurrences. The script needs to know what to do when it can't find any more such occurrences. As an example, look at the following script, which counts all open documents. For it to work, at least one document has to be open, so the script checks first to see whether in fact any documents are open and then delivers an error message that the user can understand if none is open. The rotate-EPS-graphic script earlier also used a conditional to make sure there was an EPS graphic in the document. Notice that in all three scripting languages, you use the command if to set up such conditionals.

3.1. JavaScript

if (app.document s.length==0){
 alert("No InDesign documents are open!"); }

3.2. AppleScript

tell application "Adobe InDesign CS5"
 activate
 set myNumberOfDocuments to (count documents)
 if myNumberOfDocuments = 0 then
  display dialog "No InDesign publications are open!"
 end if
end tell

3.3. VBA

Dim myInDesign as InDesign.Application
 Set myInDesign = CreateObject ("InDesign.Application.CS4")
 If myInDesign.Documents.Count
  MsgBox "No InDesign publications are open!"
 End If
End Sub

Another form of conditional is what's called a control loop, in which an action occurs either for a specified number of iterations or until a condition is met. The following scripts show an example of each for each language. Note the use of comments in the scripts — a handy way to document what you're doing for later reference. In JavaScript, a single-line comment begins with //, whereas a multiline comment begins with /* and ends with */. In AppleScript, a comment begins with --and continues until you press Enter or Return. In VBA, it begins with Rem followed by a space, and it continues until you press Enter or Return.

3.4. JavaScript

for (var myCounter = 0; myCounter < 20; myCounter++){
 //do something
}
while (myStop == false){
 /* do something, at some point setting myStop to true
 to leave the loop. */
}

3.5. AppleScript

repeat with counter from 1 to 20
 --do something
end repeat

set myStop to false
repeat while myStop = false
 --do something, at some point setting myStop to true to ⌝
leave the loop.
end repeat

3.6. VBA

For counter = 1 to 20
 Rem do something
Next counter

Do While myStop = false
 Rem do something, at some point setting myStop to true ⌝
 to leave the loop.
loop