How to Select the Document just back of the Active Document

I had the same problem. I did not want to go back to the "last viewed" doc but to the doc opened before the active one.

I use this on F1 key to go back to the previous opened document (index order -1).

It works great.

//////////////////////////////////////////////////////////////////////////////////////////////////////////
#target photoshop
// Go back to the last opened doc. If it is the oldest opened one it does not give error window and stays on it.
if(documents.length>0) {
    var thisIndexImage = getActiveDocumentIndex();
    var theDocs = app.documents; 
    if ( thisIndexImage != 0 ) {
        var openedBefore = theDocs[thisIndexImage - 1];
        } else {
        var openedBefore = theDocs[0];
        }
    app.activeDocument = openedBefore;
} else {
    alert ("You need to have any opened documents to apply this script.")
}
// Functions
function getActiveDocumentIndex(){
     var ref = new ActionReference();
     ref.putEnumerated( charIDToTypeID("Dcmn"), charIDToTypeID("Ordn"), charIDToTypeID("Trgt") ); 
     return desc = executeActionGet(ref).getInteger(stringIDToTypeID('itemIndex'))-1;
}

I may be wrong but I don’t think what you want is possible in DOM or with ActionDescriptors reliably when more than two documents are open as the order in which open images are stacked is not reflected in their indices.

Possible workarounds might be:

• Close the active Document, do whatever with the now active one, then re-open the originally active one.

• Use platform dependent code that utilizes OS behaviour. Of this I am not at all sure and could probably not help even if it was possible, but on Mac OS at least one can switch between document windows in an application with an OS command, so I assume one might be able to use that.

I’m curious if I have overlooked something obvious and if so hope on of the regulars can set me straight.