MaterialDatePicker only works correct with Editor Framework when it is attached to the View

[rwursthorn]

When you use a MaterialDatePicker in your view to store a Date-Value, but you don't show the DatePicker, it won't be attached to the view.
When you take a look at the code

    @Override
    public Date getValue() {
        return getPickerDate();
    }

    @Override
    public void setValue(Date value, boolean fireEvents) {
        if (value == null) {
            clear();
            return;
        }
        this.date = value;
        if (isAttached()) {
            suppressChangeEvent = !fireEvents;
            setPickerDate(JsDate.create((double) value.getTime()), pickatizedDateInput);
            suppressChangeEvent = false;
            label.addStyleName(CssName.ACTIVE);
        }
        super.setValue(value, fireEvents);
    }

you can see, that setValue() calls setPickerDate(JsDate.create((double) value.getTime()), pickatizedDateInput); only when the DatePicker isAttached(). But getValue() returns PickerDate unconditionally.

So when the Editor Framework calls getValue() it will return null when the DatePicker is not attached, although this.date got set correctly.

[kevzlou7979]

Thanks for your contribution for this issue.