[FEATURE] Data calculator

[BECATRUE]

Feature you want to implement

'Data calculator (hereafter referred to as datacalc)' is an app for showing the sum of two values from selected databases.

Viewer frame

• dbBoxes: A dictionary containing two comboboxes for selecting the database from which the value of A and B is fetched
• calculateButton: A button for calculating the sum of recently fetched 'A' and 'B'
• numberLabel: A label showing the sum, or an error message if something goes wrong

How the feature is implemented

Frame and App will be implemented in apps.datacalc.

Additional context

[BECATRUE]

I wonder when the sum calculation is operated? Only setting a dataset, adding a calculation button, or polling whether datas are updated?

@kangz12345

[kangz12345]

I wonder when the sum calculation is operated? Only setting a dataset, adding a calculation button, or polling whether datas are updated?

For simplicity, let's add a calculation button.

[kangz12345]

Suggestion:

• How about using a dict-like structure for the comboboxes? For example, dbBoxes["A"].

[BECATRUE]

Suggestion:

• How about using a dict-like structure for the comboboxes? For example, dbBoxes["A"].

It looks good!

[BECATRUE]

For simplicity, can I assume that the selected database has a table named A (or B), and the table has only one column.

If not, we should add two QLineEdits for typing a table name and a column name.

@kangz12345

[kangz12345]

Adding line edits looks tiresome indeed. Then, how about taking the table names as constructor arguments? Which implies that it should be given in "setup.json". If you force the table names to "A" and "B", numgen and poller should use the table name "A" or "B", and it does not look intuitive.

[BECATRUE]

Using "setup.json" looks good! I'll do it like this.