- Aug 5, 2010
Understanding Shortcomings of the Macro Recorder
Suppose you work in an accounting department. Each day you receive a text file from the company system showing all the invoices produced the prior day. This text file has commas separating each field. The columns in the file are InvoiceDate, InvoiceNumber, SalesRepNumber, CustomerNumber, ProductRevenue, ServiceRevenue, and ProductCost (see Figure 1.9).
Figure 1.9 Invoice.txt file.
Each morning, you manually import this file into Excel. You add a total row to the data, bold the headings, and then print the report for distribution to a few managers.
This seems like a simple process that would be ideally suited to using the macro recorder. However, due to some problems with the macro recorder, your first few attempts might not be successful. The following case study explains how to overcome these problems.
Examining Code in the Programming Window
Let's look at the code you just recorded from the case study. Don't worry if it doesn't make sense yet.
To open the VB Editor, press Alt+F11. In your VBA Project (MacroToImportInvoices.xls), find the component Module1, right-click the module, and select View Code. Notice that some lines start with an apostrophe—these are comments and are ignored by the program. The macro recorder starts your macros with a few comments, using the description you entered in the Record Macro dialog. The comment for the Keyboard Shortcut is there to remind you of the shortcut.
Recorded macro code is usually pretty neat (see Figure 1.11). Each noncomment line of code is indented four characters. If a line is longer than 100 characters, the recorder breaks it into multiple lines and indents the lines an additional four characters. To continue a line of code, type a space and an underscore at the end of the line.
Figure 1.11 The recorded macro is neat looking and nicely indented.
Consider that the following seven lines of recorded code is actually only one line of code that has been broken into seven lines for readability:
Workbooks.OpenText Filename:= _ "C:\invoice.txt", Origin:=437, StartRow:=1, DataType:=xlDelimited, _ TextQualifier:=xlDoubleQuote, ConsecutiveDelimiter:=False, _ Tab:=True, Semicolon:=False, Comma:=True, Space:=False, _ Other:=False, FieldInfo:=Array(Array(1, 3), Array(2, 1), Array(3, 1), _ Array(4, 1), Array(5, 1), Array(6, 1), Array(7, 1)), _ TrailingMinusNumbers:=True
Counting this as one line, the macro recorder was able to record our 21-step process in 14 lines of code, which is pretty impressive.
Test Each Macro
It is always a good idea to test macros. To test your new macro, return to the regular Excel interface by pressing Alt+F11. Close Invoice.txt without saving any changes. MacroToImportInvoices.xls is still open.
Press Ctrl+I to run the recorded macro. It should work beautifully if you completed the steps correctly. The data is imported, totals are added, bold formatting is applied, and the columns are made wider. This seems like a perfect solution (see Figure 1.12).
Figure 1.12 The macro formats the data in the sheet.
Running the Macro on Another Day Produces Undesired Results
After testing the macro, be sure to save your macro file to use on another day. The next day, after receiving a new Invoice.txt file from the system, you open the macro, press Ctrl+I to run it, and disaster strikes. The data for June 6 happened to have 9 invoices, while the data for the June 7 has 17 invoices. However, the recorded macro blindly added the totals in Row 12 because this was where you put the totals when the macro was recorded (see Figure 1.13).
Figure 1.13 The intent of the recorded macro was to add a total at the end of the data, but the recorder made a macro that always adds totals at Row 11.
This problem arises because the macro recorder is recording all your actions in absolute mode by default. Instead of using the default state of the macro recorder, the next section discusses relative recording and how this might get you closer to a final solution.
Possible Solution: Use Relative References When Recording
By default, the macro recorder records all actions as absolute actions. If you navigate to Row 11 when you record the macro on Monday, the macro will always go to Row 11 when the macro is run. This is rarely appropriate when dealing with variable numbers of rows of data. The better option is to use relative references when recording.
Macros recorded with absolute references note the actual address of the cell pointer, such as A11. Macros recorded with relative references note that the cell pointer should move a certain number of rows and columns from its current position. For example, if the cell pointer starts in cell A1, the code ActiveCell.Offset(16, 1).Select would move the cell pointer to B17, which is the cell 16 rows down and 1 column to the right.
Let's try the same case study again, this time using relative references. The solution will be much closer to working correctly.
Open MacroToImportInvoices.xls and run the new macro with Ctrl+J. This time, everything should look good with the totals in the correct places. Look at Figure 1.16—see anything out of the ordinary?
Figure 1.16 The result of running the Relative macro.
If you aren't careful, you might print these reports for your manager. If you did, you would be in trouble. When you look in cell E19, Excel has inserted a green triangle to tell you to look at the cell. If you happened to try this back in Excel 95 or Excel 97 before SmartTags, there would not have been an indicator that anything was wrong.
When you move the cell pointer to E19, an alert indicator pops up near the cell. This indicator tells you the formula fails to include adjacent cells. If you look in the formula bar, you will see that the macro totaled only from Row 10 to Row 18. Neither the relative recording nor the nonrelative recording is smart enough to replicate the logic of the AutoSum button.
At this point, some people would give up. However, imagine that you might have had fewer invoice records on this particular day. Excel would have rewarded you with the illogical formula of =SUM(E6:E1048574) and a circular reference, as shown in Figure 1.17.
Figure 1.17 The result of running the Relative macro with fewer invoice records.
If you have tried using the macro recorder, most likely you would run into similar problems as the ones produced in the last two case studies. Although this is frustrating, you should be happy to know that the macro recorder actually gets you 95 percent of the way to a useful macro.
Your job is to recognize where the macro recorder is likely to fail and then to be able to dive into the VBA code to fix the one or two lines that require adjusting to have a perfect macro. With some added human intelligence, you can produce awesome macros to speed up your daily work.
Never Use the AutoSum Button While Recording a Macro
There actually is a macro-recorder solution to the current problem. It is important to recognize that the macro recorder will never correctly record the intent of the AutoSum button.
If you are in cell E99 and click the AutoSum button, Excel starts scanning from cell E98 upward until it locates a text cell, a blank cell, or a formula. It then proposes a formula that sums everything between the current cell and the found cell.
However, the macro recorder records the particular result of that search on the day that the macro was recorded. Rather than record something along the lines of "do the normal AutoSum logic," the macro recorder inserts a single line of code to add up the previous 98 cells.
The somewhat bizarre workaround is to type a SUM function that uses a mix of relative and absolute row references. If you type =SUM(E$2:E10) while the macro recorder is running, Excel correctly adds code that will always sum from a fixed row two down to the relative reference that is just above the current cell.
Here is the resulting code with a few comments:
Sub FormatInvoice3() ' ' FormatInvoice2 Macro ' Third try. Use relative. Don't touch AutoSum ' ' Keyboard Shortcut: Ctrl+Shift+K ' Workbooks.OpenText Filename:="C:\Users\Owner\Documents\invoice.txt", Origin _ :=437, StartRow:=1, DataType:=xlDelimited, TextQualifier:=xlDoubleQuote _ , ConsecutiveDelimiter:=False, Tab:=False, Semicolon:=False, Comma:= _ True, Space:=False, Other:=False, FieldInfo:=Array(Array(1, 3), Array(2, 1), _ Array(3, 1), Array(4, 1), Array(5, 1), Array(6, 1), Array(7, 1)), TrailingMinusNumbers _ :=True ' Relative turned on here Selection.End(xlDown).Select ActiveCell.Offset(1, 0).Range("A1").Select ActiveCell.FormulaR1C1 = "Total" ActiveCell.Offset(0, 4).Range("A1").Select ' Don't use AutoSum. Type this formula: Selection.FormulaR1C1 = "=SUM(R2C:R[-1]C)" Selection.AutoFill Destination:=ActiveCell.Range("A1:C1"), Type:= _ xlFillDefault ActiveCell.Range("A1:C1").Select ' Relative turned off here ActiveCell.Rows("1:1").EntireRow.Select ActiveCell.Activate Selection.Font.Bold = True Cells.Select Selection.Columns.AutoFit Range("A1").Select End Sub
This third macro will consistently work with any size dataset.
To see a demo of recording this macro, search for Excel VBA 1 at YouTube.
Three Tips When Using the Macro Recorder
You will rarely be able to record 100 percent of your macros and have them work. However, you will get much closer by using these three tips demonstrated in the following subsections.
Tip 1: Use Relative References Setting Usually Needs to Be On
Microsoft should have made this setting be the default. Unless you specifically need to move to Row 1 from the bottom of a dataset, you should usually leave the Use Relative References button in the Developer tab turned on.
Tip 2: Use Special Navigation Keys to Move to Bottom of a Dataset
If you are at the top of a dataset and need to move to the last cell with data, you can press Ctrl+down arrow or press the End key and then the down-arrow key.
Similarly, to move to the last column in the current row of the dataset, press Ctrl+right arrow or press End and then press the right-arrow key.
By using these navigation keys, you can jump to the end of the dataset, no matter how many rows or columns you have today.
Tip 3: Never Touch the AutoSum Icon While Recording a Macro
The macro recorder will not record the "essence" of the AutoSum button. Instead, it will hard-code the formula that resulted from pressing the AutoSum button. This formula does not work any time you have more or fewer records in the dataset.
Instead, type a formula with a single dollar sign, such as =SUM(E$2:E10). When this is done, the macro recorder records the first E$2 as a fixed reference and starts the SUM range directly below the Row 1 headings. Provided the active cell is E11, the macro recorder recognizes E10 as a relative reference pointing directly above the current cell.