Scrollable "tabs" using ion-segment


#1

I’m trying to emulate the Material Design scrolling tabs as seen here: https://material.io/guidelines/components/tabs.html#tabs-specs

I want the segments to scroll horizontally and, by default, scroll the selected segment button into view. I have the ion-segment object on a component that has vertical scrolling, which seems to work well for the scrolling part, but I haven’t been able to figure out how to scroll the selected segment into view. If anyone has done something like this, I’d love some help. :smile: How do I scroll into view a selected segment button? Do I have to use an ion-scroll object?


#2

@btsiders did you figure out how to do it? I’m facing the same issue.


#3

Good to see it’s not just me. :smile:

No, I don’t have scroll-into-view segments yet. Since I’m still just prototyping, I’ve moved on to other problems to let this one simmer for a while.


#4

Yeah, the same for me haha. I found a solution to make it scroll using only CSS. However, it doesn’t work on swipe. :confused:



#5

So I revisited this and came up with something that seems to be working in Chrome on the desktop that is emulating a mobile device. I haven’t checked it on a device yet.

// Scroll selected segment into view on mobile
if (this.platform.is('mobile')) {
	var selectedValue = this.segment.value;

	// I don't like working with underscore objects,
	// but this seems *slightly* nicer than working with native elements at this point, 
	// and it seems to be the easiest way to find the selected index
	var selectedIndex = this.segment._buttons.toArray().findIndex(function(button) { 
		return button.value === selectedValue; 
	});
    			
	// Of course, now I need to work with the native element...
	var nativeSegment = <Element>this.segment.getNativeElement();
	
	// I pass in false to keep my page from scrolling vertically. YMMV
	nativeSegment.children[selectedIndex].scrollIntoView(false);
}

This is after setting up the CSS to do scrolling. In my case, the ion-segment object is wrapped in a custom component of mine, so I have the scrolling CSS on that element instead of directly on the ion-segment, but it’s basically the same as the CSS in https://github.com/driftyco/ionic/issues/7202.

First off, import needed objects from @angular/core and ionic-angular, of course. The segment object above comes from a @ViewChild(Segment) segment: Segment;

When should you do this? Well, since my segments are being used as navigation to pages that are then set as root on my current tab, and since I am using the workaround for the ion-segment-button *ngFor issue, I run this in my ViewController's didEnter. That may not be the right spot for anyone else, but it seems to be working for me.


#6

It seems to be a nice solution! :smiley:

I’ll have a closer look when I’ll revisit this issue next week.


#7

This is really awesome, but how can I center the selected segment button afterwards automatically? Any idea?


#8

I hope my tutorial will help :wink: Tutorial