Navigation Screen

balqis almari

Rank: #9592

Solved

Question

Traditional Web

Application Type

Traditional Web

How I could pass list value from WebBlock to Navigation screen

that's error appear when try to pass list parameter to screen :

Invalid Link

Arguments of 'RecordList' data type are not allowed in links with 'Method' property set to 'Navigate'.

on 2020-11-19

Maria da Graça Peixoto

Rank: #218

Solution

Hi!

The problem is exactly that , a screen can not receive a list as parameter.

There are several solutions to your problem here are two:

1 . If yours is a big list try to create an entity to hold the list and send only an identifier that is common to all the records you have in your list . After using the list dose records can be deleted.

2 . If list as just a few records, use widget JSONSerialize to transform the list in a text send that text as the parameter

in the new screen use JSONDeserialize to transform the text in a list variable.

Hope this help

Graça

on 2020-11-19

2 replies

Last reply on 2020-11-23

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balqis almari

Rank: #9592

I try it, but this error appears when used JsonDeserialize :

404 - File or directory not found.

The resource you are looking for might have been removed, had its name changed, or is temporarily unavailable.

on 2020-11-21

Maria da Graça Peixoto

Rank: #218

Replying to balqis almari's comment on 21 Nov 2020 20:05:23

Hi!

I do not understand what can be happening in your work.

Please see an example in the attached .oml

Hope this helps

Graça

JSONExample.oml

on 2020-11-23

Nordin Ahdi

mvp_badge

MVP

Rank: #72

Hi Balqis,

The question you ask is how could I pass a List from a Web Block to a Parent Screen, correct?

In this case you need to use Events in order to pass data from a Web Block to a Screen.

Since you are developing a Traditional Web Application, you are not allowed to use an Input Parameter of type List in the Handler of the Event on the Parent Screen. However, there is a little trick (other than JSON Serialize/Deserialize) that would still allow you to pass a List from a Web Block to a Parent Screen through an Event.

For that, you would need to define a Structure with an Attribute of type List like the following example.

Now you can use this Structure as a data type for the Input Parameter of the Event inside the Web Block. Since it contains a List as an attribute, you can append values to that List before triggering the Event. This will allow you to pass the List to the Parent Screen through an Event.

See example here: https://nordinahdi.outsystemscloud.com/PassListBlock2Screen/

The OML is attached.

Hope this helps!

Regards,

Nordin

PassListBlock2Screen.oml

on 2020-11-19

2 replies

Last reply on 2020-11-23

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balqis almari

Rank: #9592

Hi Nordin ,

i want to open PopUp Screen from Webblock , i try to create Structure but didn't work it still the same error appears .

on 2020-11-21

Nordin Ahdi

mvp_badge

MVP

Rank: #72

Replying to balqis almari's comment on 21 Nov 2020 20:07:51

Hi Balqis,

Since you want to pass the List to a Popup, you are better of using JSON Serialize/Deserialize as suggested by Maria.

The steps I used are:

JSON Serialize the List on click of a button
Store the JSON in a Session Variable
Use Widget_Click to click a Hidden Button that opens the Popup
In the Preparation of the Popup screen, Deserialize the JSON back into a List

>> NOTE: this is to demonstrate that it is possible to build this, however it is not a best practice to pass Lists to screens nor to store large values in Session Variables for that matter.

See sample here: https://nordinahdi.outsystemscloud.com/PassListBlock2Popup/ParentScreen.aspx

I have attached the sample OML.

Hope this helps.

Regards,

Nordin

PassListBlock2Popup.oml

on 2020-11-23

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