Toast toast = Toast.makeText(this, content, Toast.LENGTH_SHORT);
    toastView.findViewById(android.R.id.message);
    View toastView = toast.getView();
    Drawable toastBg = toastView.getBackground();
    Drawable drawable = tintDrawable(toastBg, ColorStateList.valueOf(Color.RED));
    toastView.setBackground(drawable);
    toast.setView(toastView);
    toast.show();

public  Drawable tintDrawable(Drawable drawable, ColorStateList colors) {
    final Drawable wrappedDrawable = DrawableCompat.wrap(drawable);
    DrawableCompat.setTintList(wrappedDrawable, colors);
    return wrappedDrawable;
}