为什么动画执行失败？

var main = plus.android.runtimeMainActivity();  
var Intent = plus.android.importClass("android.content.Intent");  
var intent = new Intent();  
intent.setClassName(main, aclass);  

if (!parameters) {  
    var Bundle = plus.android.importClass("android.os.Bundle");  
    var bundle = new Bundle();  
    bundle.putString("parameters", parameters);  
    intent.putExtras(bundle);  
}  

var Rclass  = plus.android.importClass("cn.***.****.R");  
var rclass = new Rclass();  
var in_from_right = rclass.anim.in_from_right;  
var out_from_left = rclass.anim.out_from_left;  
main.startActivity(intent);  
main.overridePendingTransition(in_from_right, out_from_left);  

为啥动画执行不了？

@DCloud_Android_磊子