Header view drawn multiple time

[IHNEL]

Hi,
I implement my recycler-view using FlexibleAdapter within AbstractHeaderItem and AbstractSectionableItem to make sticky-header list.

There are 3 list items which assigned 3 header items. 3 these header items have same data, and of course I implemented the equals method to return whether they are same. The issue is the header items drawn multiple time as below screenshot

If I created unique header data item and then set to all 3 items, then it draw correctly. What I am expecting is I can create header data item dynamically based on given data-fields, and there is a way to group same headers into a section.

Did I make any mistake?

[davideas]

@IHNEL, well a mistake was done. Review your code to be sure the same header object is assigned to the 3 items, or maybe equals is not implemented properly. Read again the wiki for equals or simply read the method comments.

[IHNEL]

@davideas Thank for quickly reply.
I created a new header object every time insert new item. Each header object has a fieldname, and I wrote the equals like this (I'm using Kotlin) :

override fun equals(other: Any?)
= other is HeaderView && other.name == this.name

I debug and see the equals method works fine. Of course the name I set to 3 header objects is same string.

[davideas]

@IHNEL, uhm theoretically it shouldn't work if you assign the same name. Can you check which is the reference in memory for the 3 header items?
Debug and watch the list in the Adapter.
Possibly assign the same object so you see the difference between the 2 approaches.

The header is displayed and inserted if it is seen as hidden, so in memory they should be different.
Also initialize the list only with items (no headers).

[davideas]

I closed due to inactivity, but also the approach used should be refined.

[IHNEL]

@davideas sorry for quite lately reply. I didn't keep good notification in Github.
Of course the memory references are difference cos I initialized 3 difference objects for header. But I think it should rely on the equals method to check that they should be on same group.

[davideas]

@IHNEL, the function getHeaderOf() takes the header instance of the item, and on it is checked if it is hidden or not, then displayed, so it must be the same instance.

[IHNEL]

Ok, Got it. Seems I have to reconsider my data structure.
Thank you so much,

[IHNEL]

I debug and see that the method equals of header view didn't be call. I spent much of time to investigate but don't know why it runs into this case.
Any recommendation?

[davideas]

@IHNEL, the equals method is called when you get an item from the list or when it is explicity called.
With the last Snapshot I improved the calls on equals for managing Headers, check commits in issue #357.

[IHNEL]

Thank. Finally I found the cause.
The equals() method wasn't called if I set up the adapter like this:
adapter.setDisplayHeadersAtStartUp(true).setStickyHeaders(true)

And it works like a charm when I turn to this.

       adapter.setStickyHeaders(true)
        adapter.setStickyHeaders(true)