Tip: Interface patterns give you an opportunity to explore different interface designs. Be sure to check out How to Adapt a Pattern for Your Application.
Limit the number of rows that can be selected to an arbitrary number.
Note: This expression uses direct references to the Employee record type, created in the Records Tutorial. If you've completed that tutorial in your environment, you can change the existing record-type references in this pattern to point to your Employee record type instead.
This is a more elaborate version of the Limit Grid Selection to One Row pattern.
This scenario demonstrates:
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a!localVariables(
local!selection,
local!selectedRows,
/* This is the maximum number of rows you can select from the grid. Selections that exceed
this value are dropped from local!selectedRows. */
local!selectionLimit: 2,
/* This stores the last dropped row that exceeded the selection limit. */
local!errorDrop,
{
a!columnsLayout(
columns: {
a!columnLayout(
contents: {
a!gridField(
label: "Employees",
labelPosition: "ABOVE",
instructions: "Select up to " & local!selectionLimit & " employees.",
data: recordType!Employee,
columns: {
a!gridColumn(
label: "ID",
sortField: "id",
value: fv!row[recordType!Employee.fields.id],
width: "ICON"
),
a!gridColumn(
label: "First Name",
sortField: "firstName",
value: fv!row[recordType!Employee.fields.firstName]
),
a!gridColumn(
label: "Last Name",
sortField: "lastName",
value: fv!row[recordType!Employee.fields.lastName]
),
a!gridColumn(
label: "Phone Number",
sortField: "phoneNumber",
value: fv!row[recordType!Employee.fields.phoneNumber]
)
},
pagesize: 10,
selectable: true,
selectionstyle: "ROW_HIGHLIGHT",
selectionvalue: local!selection,
selectionsaveinto: {
local!selection,
a!save(local!selectedRows, append(local!selectedRows, fv!selectedRows)),
a!save(local!selectedRows, difference(local!selectedRows, fv!deselectedRows)),
/* If the length of the selected rows is greater than the limit, this saves the excess
selection in local!errorDrop so we can tell the user which row was dropped. */
if(length(local!selectedRows) > local!selectionLimit,
a!save(local!errorDrop, fv!selectedRows),
a!save(local!errorDrop, null)
),
/* We use the rdrop() function to remove the most recent selections, so only the
first-selected rows, up to the limit, remain. If you want the reverse behavior,
dropping the oldest selections instead, replace rdrop() with ldrop().
The max() function is used as a simple way to handle negative numbers for when
the selection length is less than the limit. */
a!save(local!selectedRows, rdrop(local!selectedRows, max(0, length(local!selectedRows)-local!selectionLimit))),
a!save(local!selection, rdrop(local!selection, max(0, length(local!selection)-local!selectionLimit)))
},
validations: a!validationMessage(
message: "The total cannot be greater than $1,000",
validateAfter: "REFRESH",
showWhen: true
)
)
},
width: "WIDE"
),
a!columnLayout(
contents: {
a!sectionLayout(
label: "Selected Employees",
contents: {
a!forEach(
items: local!selectedRows,
expression: a!textField(
label: fv!index&". "&fv!item[recordType!Employee.fields.firstName]&" "&fv!item[recordType!Employee.fields.lastName],
value: " "&fv!item[recordType!Employee.fields.phoneNumber],
readOnly: true
)
)
}
),
a!richTextDisplayField(
label: "Rich Text",
labelPosition: "COLLAPSED",
value: {
a!richTextItem(
text: {
if(
not(isnull(local!errorDrop)),
"Can't add "
&local!errorDrop[recordType!Employee.fields.firstName] &" "& local!errorDrop[recordType!Employee.fields.lastName] &"."
&char(10)&"Maximum selections: "&local!selectionLimit,
""
)
},
color: "NEGATIVE",
style: {
"STRONG"
}
)
}
)
}
)
}
)
}
)
Limit the Number of Rows in a Grid That Can Be Selected
