How to determine when ScrollContainer has a scroll?

santanu

Currently, we're adding items inside a ScrollContainer component. I vaguely remember we able to determine when the container gets a scroll with following code, previously, but seems not to work anymore.

We has this code in a custom TabNavigator component where we also has our ScrollContainer added:

this.tabScroller = new ScrollContainer();
this.tabScroller.showScrollBars = false;
this.addChild(this.tabScroller);

override private function layoutContent():Void 
    {
        this.tabScroller.width = this.actualWidth;
        this.tabScroller.validateNow();
        if (this.tabScroller.maxScrollX != 0)
        {
            trace("ScrollContainer has scroll");
        }
        else
        {
            trace("ScrollContainer has no scroll");
        }
        super.layoutContent();
    }

joshtynjala

The following code is working correctly for me in a blank project:

var tabScroller = new ScrollContainer();
tabScroller.showScrollBars = false;
this.addChild(tabScroller);

var child = new Label("Hello");
child.x = 190;
tabScroller.addChild(child);

tabScroller.width = 200;
tabScroller.validateNow();
if (tabScroller.maxScrollX != 0) {
	trace("ScrollContainer has scroll", tabScroller.maxScrollX);
} else {
	trace("ScrollContainer has no scroll", tabScroller.maxScrollX);
}

Because 190 + child.width > 200, it means that maxScrollX > 0.

If I don't add the child, then it correctly determines that it doesn't need to scroll, and maxScrollX == 0.

santanu

I noticed there was a problem in child creation inside ScrollContainer at my side which I was overlooking previously.

Thanks for taking a look into this, @joshtynjala , and also sorry for the noise. I have adjusted my side to make this work again.