Improved list names and default values in File > New Data Frame dialog

[anastasia-mbithe]

fixes #7771
fixes #7799
This is still in progress, am working to fix some emerging bugs.

[anastasia-mbithe]

@rdstern, this is ready for review. Kindly have a look at it.
Though I couldn't get to use the last name, so I used the name from the second control that shows the lists per category.

[anastasia-mbithe]

The last commit includes changes that fixes #7799 as well.

[lloyddewit]

The last commit includes changes that fixes #7799 as well.

I updated the PR description so that when this PR is merged, it automatically closes the issue.

[rdstern]

On the File > New, I was ok with the row numbers being 10 and not I million.
Then when you press to see the names I am happy with the first variable x1, as you have it.
The second variable should be left as it was before, i.e. as a character variable filled with NA.
So:

[rdstern]

@anastasia-mbithe in my comment above I realise that the 1,1000000 looks a bit odd for a beginner. So make it 1,1000 instead I think. Then it does not need changing for any data frame up to 1000.

[anastasia-mbithe]

@rdstern, I can't get a way of separating the change in the first row not to affect the second row, since the code fills the grid up to the nth row. It can however be done manually when one is using the dialog. @N-thony, you can check whether my view/ suggestion is correct.

[rdstern]

@N-thony could you examine the code for the defined variables? It should be easy to have the default of the first variable being numeric (with a variable from 1 upwards), while the default for any remaining variables remains as a character variable?

[anastasia-mbithe]

@N-thony , kindly have a look at this.

[N-thony]

you can remove this and keep it as it was.

[N-thony]

.Item(iRow).Cells(2).Value = "Character"
.Item(iRow).Cells(3).Value = "NA"

it should remain character at this step

[N-thony]

@rdstern could you test?

[rdstern]

@anastasia-mbithe and @N-thony I was poised to say we should give in on these changes. That's because they were taking too long, and were not so important. But to my great pleasure it all seems to work fine now. That's really great. Many thanks! @lloyddewit I hope the code is ok so this can be merged.