Function to toggle active layer visibility

toggleActiveLayerVisibility.jsx

toggleActiveLayerVisibility(true);

function toggleActiveLayerVisibility(toggleOptionsPalette) {
    var s2t = function (s) {
        return app.stringIDToTypeID(s);
    };
    var descriptor = new ActionDescriptor();
    var list = new ActionList();
    var reference = new ActionReference();
    reference.putEnumerated(s2t("layer"), s2t("ordinal"), s2t("targetEnum"));
    list.putReference(reference);
    descriptor.putList(s2t("null"), list);
    descriptor.putBoolean(s2t("toggleOptionsPalette"), toggleOptionsPalette);
    executeAction(s2t("show"), descriptor, DialogModes.NO);
}

// or

/*
// Set back layer visibility to true
//Select back layer  - Fails if back layer is in a group/set which becomes selected
var doc = app.activeDocument;
doc.activeLayer = doc.layers[doc.layers.length - 1];
//Set active layer to visible, regardless of current visibility
doc.activeLayer.visible = true;
*/

// or

/*
activeLayerVisibility("Shw "); // "Shw " | "Hd  "

function activeLayerVisibility(toggle) {
    var c2t = function (s) {
        return app.charIDToTypeID(s);
    };

    var descriptor = new ActionDescriptor();
    var list = new ActionList();
    var reference = new ActionReference();

    reference.putEnumerated(c2t("Lyr "), c2t("Ordn"), c2t("Trgt"));
    list.putReference(reference);
    descriptor.putList(c2t("null"), list);
    executeAction(c2t(toggle), descriptor, DialogModes.NO);
}
*/