Getting Started
To get started go to https://web.powerapps.com, click on start from blank or open one of your existing apps that are connected to a SharePoint list. These steps will help you when you have a form on your app connected to your SharePoint list. To add a form, click on Insert on the top of the studio then click on Forms, then edit. The form will appear on your screen and will show the data panel. Select your SharePoint list or if you do not have one in the drop down click on “Add a data source” to select one.
Once you select your SharePoint list you will notice that all of the columns from your list will be checked, uncheck any of the columns that you do not need. Often when we’re creating an app that uses a SharePoint list as the data source, we want to define certain values to be selected by default when creating new items.
Text / number / date columns
To change the default value for any column in the edit form, you need to update the property that defines the default value in the control that is used to edit that property. You’ll also only want to define that default value for new items – if the form is editing an existing item, the form should display the current value for that column. You can do that with the If function, checking for the Mode property of the edit form control. For example, if you want to define the default value for a numeric column to zero, you can change the Default property of the text input control in the form from:
Parent.Default
to
If(EditForm1.Mode = FormMode.New, 0, Parent.Default)
Where EditForm1 is the name of the edit form control. In this formula, if the form is being used to add new items, then the default (zero) will be used. Otherwise (edit or view mode) the control will use the default value from the card, which has the current value for the selected item. Notice that you will have to unlock the card to update the property of the text input control. To do that, select the control (or the card), and in the property panel on the far right, click on Advanced, and then click on “Unlock to change properties”.
Text columns are similar – they use the same text input control by default as numeric columns. Date columns use the date picker control, and the expression would also be similar, except that it would use the DefaultDate property of that control.
Choice columns
Unlike “simple” controls like the text input or the date picker that have a single default value, the combo box control has a different way of defining its default values, so, the default expression needs to be defined appropriately. The combo box control is used in Choice, Lookup and Person column types – and since those types have the option of single and multiple selection, the default expression will change accordingly.
Choice columns are those where the user can select from a pre-defined list of values. For example, if you have a column called ‘TimeOfDay’, we could have the list of [‘Morning’, ‘Afternoon’, ‘Evening’ and ‘Night’] as possible values – that’s a typical single-selection scenario. Or if you have a list that stores kitchen products, a column called ‘Intended Uses’ with possible values [‘Day-to-day’, ‘Formal dining’, ‘Gifts’, ‘Other’] would be a scenario where multiple selections are acceptable. In forms choice columns are mapped to the combo box control – which uses the DefaultSelectedItems property to determine the default values – and the value of this property can be both a single item (for the case of single selection columns) or a table (for the case of multiple selection scenarios).
While choice columns on the surface look like a text column with certain restriction, they are implemented in SharePoint as an object, that references the list of possibilities for that column. If you tried to define the default property as follows:
If(
EditForm1.Mode = FormMode.New,
"Morning",
Parent.Default)
It would give an error. Instead, you need to define it as a record with a property called Value, and that would define ‘Morning’ as the default value for that card when the card is in the New mode:
If(
EditForm1.Mode = FormMode.New,
{ Value: "Morning" },
Parent.Default)
For columns that support multiple selections, you need to use a table (collection) of data instead. So if you want to define the that ‘Day-to-day’ and ‘Gifts’ are the default values for the ‘Intended Uses’ column, we would use the following expression:
If(
EditForm1.Mode = FormMode.New,
Table({ Value: "Day-to-day" }, { Value: "Gifts" }),
Parent.Default)
Lookup columns
Those are columns for which the user can select a value from another table. This time, using the value only is not enough – it’s possible that there are multiple items in the table that is being looked up that have the same value for the referenced column, so we also need to specify the Id property of those values. The best way to retrieve it is to use the Choices function, which returns both the referenced column in the lookup, as well as the identifier of the value. So if you have a column named ‘Department’ of type lookup to another list ‘Departments’, and we know that the value that you want to use as the default is ‘Sales’, we can use a LookUp function if the column only allows single selection:
If(
EditForm1.Mode = FormMode.New,
LookUp(
Choices(MyListName.Department),
Value = "Sales"),
Parent.Default)
Likewise, if the column supports multiple selection, then you’d use a Filter expression on the possible choices to define the default selected values:
If(
EditForm1.Mode = FormMode.New,
Filter(
Choices(MyListName.RelatedDepartments),
Value = "Sales" Or Value = "Human Resources"),
Parent.Default)
Chris Memo 