Vba excel custom function not updating
Before we look at some examples, let's get the negatives out of the way first. I will refer to Custom Functions as UDF's (User Defined Functions) Creating a UDF requires the use of VBA - there is no way around it.
This means a user cannot Record a UDF, you have to create the UDF yourself.
Excel cannot examine the VBA code within the UDF and identify cells that may influence the function's output.
So while the function's author may construct the function to return different results based on any number of changes made in the workbook, the only cells Excel knows will change the function's result are the declared inputs.
A UDF should update automatically if the data content of any cell it references changes, this does not include format changes etc.
To have any UDF update as a Volatile Function (eg NOW TODAY etc) you would need to use: Application. However, be aware that too many Volatile function can slow down Excel.
I hit this while hoping to update all user defined functions whenever an Active X textbox was changed even if they didn't affect linked cells which were used as inputs to the UDF.A UDF cannot use many of Excels built in features such as Auto Filters, Advanced Filters, Find, Replace to name but a few!We can use a UDF to Call (Run) another standard Procedure, but if we do the standard Procedure will then be under the same restrictions as the UDF itself.SUM(r Cell) v Result End If Next r Cell Else For Each r Cell In r Range If r Cell. Color Index = l Col Then v Result = 1 v Result End If Next r Cell End If Color Function = v Result End Function It works fine and gives me the expected result if I click the green tick in the formula bar but won't update automatically after I colour another cell.How do I set it to automatically update the count every time I manually colour a cell elsewhere on the spreadsheet?