After Effects│選択したレイヤーの文字の状態を変更するスクリプト

(function () {
    var comp = app.project && app.project.activeItem;
    if (!(comp instanceof CompItem)) { alert("Open a composition."); return; }
    var layers = comp.selectedLayers, targets = [];
    if (!layers.length || layers.length > 20) { alert("Select 1 to 20 static text layers."); return; }
    for (var i = 0; i < layers.length; i++) {
        var layer = layers[i];
        if (!(layer instanceof TextLayer) || layer.locked) {
            alert("Select unlocked text layers only."); return;
        }
        var source = layer.property("ADBE Text Properties").property("ADBE Text Document");
        if (source.numKeys || source.expression !== "") {
            alert("Source Text must have no keys or existing expression."); return;
        }
        targets.push({source:source, doc:source.value});
    }
    var changed = 0;
    app.beginUndoGroup("Change selected text fill and stroke");
    try {
        for (i = 0; i < targets.length; i++) {
            var doc = targets[i].doc;
            doc.applyFill = true; doc.fillColor = [0, 0, 0];
            doc.applyStroke = true; doc.strokeColor = [1, 1, 1]; doc.strokeWidth = 2;
            targets[i].source.setValue(doc); changed++;
        }
    } catch (error) {
        alert("Stopped after " + changed + " changes. Undo or reopen the practice copy.\n" + error);
    } finally { app.endUndoGroup(); }
}());