Function to show/hide layer with Photoshop script (JSX)

Question

I am writing a script that will loop through layers, trim them and export. So far I have most of all the element I need to complete this script. The only thing I can't find is how to show/hide an individual layer. I've found functions to show/hide all layers but nothing for one single layer.

///////////////////////////////////////////////////////////////////////////////
// selectAllLayers - select all layers (Select > All Layers)
///////////////////////////////////////////////////////////////////////////////
function selectAllLayers() {
    var ref = new ActionReference();
    ref.putEnumerated(cTID('Lyr '), cTID('Ordn'), cTID('Trgt'));
    var desc = new ActionDescriptor();
    desc.putReference(cTID('null'), ref);

    executeAction(sTID('selectAllLayers'), desc, DialogModes.NO);
}

///////////////////////////////////////////////////////////////////////////////
// hideLayers - hide all selected layers (Layer > Hide Layers)
///////////////////////////////////////////////////////////////////////////////
function hideLayers() {
    var ref = new ActionReference();
    ref.putEnumerated(cTID('Lyr '), cTID('Ordn'), cTID('Trgt'));
    var list = new ActionList();
    list.putReference(ref);
    var desc = new ActionDescriptor();
    desc.putList(cTID('null'), list);
    executeAction(cTID('Hd  '), desc, DialogModes.NO);
}

function cTID(s) {return app.charIDToTypeID(s);}
function sTID(s) {return app.stringIDToTypeID(s);}

Any ideas?

Answer 1

The Layer object has a .visible boolean property which you can use to control visibility for each layer individually:

// make active layer invisible
app.activeDocument.activeLayer.visible = false;

or

// make active layer visible
app.activeDocument.activeLayer.visible = true;

or even toggle visibility for the selected/active layer:

app.activeDocument.activeLayer.visible = !app.activeDocument.activeLayer.visible;

or loop through what layers you need and toggle their visibility:

//example hides odd layers while showing even layers, based on their index
var doc = app.activeDocument;
for(var i = 0 ; i < doc.layers.length;i++){
    doc.layers[i].visible = (i % 2 == 0);
}

I suggest having a looks either in the Photoshop CS5 Javascript Reference (PDF link) or in ExtendScript Toolkit's Object Model Viewer.

You can access it via Help > Object Model Viewer and select the Adobe Photoshop CS5 Object Library from the browser combobox/list to the list of classes available in the Photoshop DOM.