Mastering PowerApps Combobox How to Set and Clear Single Select Choices Programmatically

Mastering PowerApps Combobox: How to Set and Clear Single Select Choices Programmatically


In the dynamic realm of PowerApps development, especially when harnessing the PowerApps ComboBox Programmatically Control, it’s not uncommon to be presented with scenarios demanding the programmatic control of UI elements. Through PowerApps ComboBox Programmatically Control, we can address real-world scenarios such as the one discussed with the SharePoint list.

Understanding the PowerApps ComboBox Programmatically Control Context

Crafting data entry interfaces with single-select SharePoint choice columns can be intricate. Especially when there arises a necessity to programmatically set or reset ComboBox values and concurrently ensure that the form correctly displays pre-existing data. Consider a real-world instance where a SharePoint list manages issue reporting. Two crucial fields, ‘close datetime’ and issue status, play pivotal roles. The aspiration is simple: Should a user specify a ‘close datetime’, the issue status should automatically toggle to ‘closed’. Conversely, retracting a ‘close datetime’ should reset the issue status. This list primarily houses the IssueStatus as a single-select choice column with possible selections like In Progress, Open, and Closed.

Blueprint for Effective PowerApps ComboBox Control

To implement this dynamic behavior, our strategy leverages variables that react to the ‘close datetime’ alterations. The IssueStatus ComboBox’s DefaultSelectedItems property references this variable, governing its displayed options.

Using a PowerApps auto-generated app, anchored on our SharePoint list, navigate to the form’s date picker control (renamed here as DateTimeSelector). The control’s OnChange property adopts the formula:

If(IsBlank(DateTimeSelector.SelectedDate), Set(StatusVar,"null"), Set(StatusVar,"Closed") )

If functions in Power Apps
Blank, Coalesce, IsBlank, and IsEmpty functions in Power Apps

This formulation sets the StatusVar variable based on the state of our DateTimeSelector.

Progressing, the DefaultSelectedItems property for the Issue Status ComboBox incorporates:

If(StatusVar="", Parent.Default, If(StatusVar="null", {}, LookUp(Choices(Issues.Status), Value=StatusVar) ) )

This logic discerns the correct display value for our ComboBox.

To ensure flawless operation, initialize the StatusVar with an empty string during form load. This can be orchestrated via the OnVisible property:


Reference: Set function in Power Apps

A pivotal step remains: resetting an existing choice. Merely displaying an empty ComboBox doesn’t suffice to erase its data upon record submission. Overcome this by setting the choice Id to -1 within the data card’s Update property that houses the ComboBox:

If(StatusVar="null", { '@odata.type':"#Microsoft.Azure.Connectors.SharePoint.SPListExpandedReference", Id:-1, Value:"" }, ComboBoxChoice.Selected )

Conclusion: The Impact of PowerApps ComboBox Programmatically Control on Dynamic Forms:

Harnessing the power of PowerApps to set and clear ComboBox values programmatically is integral for interactive and dynamic forms. This walkthrough illuminated the intricacies of achieving this feat using variable-driven logic. Should you find yourself navigating tumultuous PowerApps waters or require technical assistance, our team is a mere click away. Dive into our reservoir of expertise and elevate your PowerApps experience.

If you want to learn more about the Power Apps, feel free to explore our other informative articles and tutorials.

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