Validation Alerts

Summary

Validation Alerts can prevent bad edits
They will fire before the edit is committed, preventing a round trip to the server

Validation Alerts can be used to prevent cell edits which break the rule set in the Alert Definition.

This is done by specifying PreventEdit in the AlertProperties property to true.

Note

If a Prevent Edit Alert is too inflexible, an Alert with a an Undo Action can be used instead

Validation Alerts are designed to avoid this common, and extremely annoying, scenario:

an edit is made and commmitted
all other users of the application see this edit
server validation then kicks in and forces the cell to 'jump back' to its initial value in all users' grids

Hint

An alternative to validation Alerts is to create an Alert with a custom form enabling users to provide a new value
This can be achieved via an Adaptable Form with 2 Buttons that reference Grid API methods when clicked

Alerts: Validation Alerts

Fork Fork

This example contains a Validation Alert which prevents a cell edit which sets Github Stars to 0
It is of type Error and displays a Notification when the Alert fires

Expand to see the Alert Definition

Alert: {
  AlertDefinitions: [
    {
      Name: 'alert-github_stars',
      MessageType: 'Error',
      Scope: {
        ColumnIds: ['github_stars'],
      },
      Rule: {
        Predicate: {
          PredicateId: 'Equals',
          Inputs: [0],
        },
      },
      AlertProperties: {
        PreventEdit: true,
        DisplayNotification: true,
      },
    },
  ],
},

Try It Out

Set a GitHub Stars value to 0 and see the change being reverted and the Alert notification displayed

FAQ

How do Validation Alerts differ from ReadOnly Cells The main difference is when the evaluation is peformed:

Use ReadOnly cells ( via isEditable property in Edit Options) to validate before the edit (using the initial cell value)
Validation Alerts are evaluated after the proposed edit using the new cell value

AdapTable Resources

Data Validation on the Client

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