topic Re: Independent "Back Selection" functionality in QlikView

Independent "Back Selection" functionality

vlad_komarov — Thu, 01 Oct 2015 20:10:30 GMT

Hello,

In my application I am doing some UI manipulations based on list of items selected in the list box.

I need to create a “Back Selection” functionality for this Field and this functionality should be independent from standard QV Back / Forward operations.

Seems like straightforward process: using “SelectinField” action with parameter of string constructed from items selected one step back.

I am using the a variable vBack = '(' & Concat({$1}[FIELD_1], '|') &')' which gives me the proper sting in all cases except one:

It return ALL items listed in FIELD_1 when I am selecting any item first time the selection is made (after no selections were made).

I was trying to use GetFieldSelections() or GetSelectedCount(), but they do not have a SetAnalysis option for Previous step {$1}.

Any suggestions about how to handle this issue?

Regards,

Vladimir

Re: Independent "Back Selection" functionality

settu_periasamy — Fri, 02 Oct 2015 03:09:40 GMT

Hi,

May be like this..

vBack = If(GetSelectedCount([FIELD_1])>0,'(' & Concat({$1}[FIELD_1], '|') &')' ,'')

Re: Independent "Back Selection" functionality

jonathandienst — Fri, 02 Oct 2015 05:37:33 GMT

Is that really a problem? Selecting all items is the same as selecting nothing (assuming no nulls). Is that not the correct 'back' state when you make your first selection?

Re: Independent "Back Selection" functionality

vlad_komarov — Fri, 02 Oct 2015 14:36:30 GMT

Jonathan,

Yes, in QV selections terms, "No Selections" = "All Selected". But I am using these selections to activate corresponding columns in a large straight table. So "No Selections" means no columns are visible. Selecting all items will force all columns in straight table to be displayed. Trying to avoid that...

Vladimir

Re: Independent "Back Selection" functionality

Fri, 02 Oct 2015 15:44:41 GMT

it sounds like what you want to do is make the coluns conditional. You can use the conditional attribute on an expression or dimension - when you activate you would place the expression that you would want to column to appear. If the expression is not satisfied, the dimsion or expression does not appear

Re: Independent "Back Selection" functionality

vlad_komarov — Fri, 02 Oct 2015 18:04:47 GMT

Adam,

I am pretty familiar with "Conditional" option and how to show/hide individual column(s).

The question was about different thing - how to use List Box selections to activate this option in each column.

Vladimir