Using the google sheets api after completing quickstart tutorial

问题

I'm pretty new to Android app development so please forgive my naivety.

I'm currently trying to develop an app that can pull data from a google spreadsheet and write data to it.

I've completed the quickstart tutorial so my code is the same as that right now. It all works correctly.

My issue is I need to be able to read from my own spreadsheet and I don't really understand the code used so I'm struggling to know where to start.

I've looked at this to try and implement the authorisation in fewer steps which I thought might make the code easier to understand - but again my lack of knowledge means I don't know how this fits into all the methods I currently have.

I've looked at the developer documentation and tried to replace the code from the quickstart which retrieves data from the app with this:

ValueRange result = service.spreadsheets().values().get(spreadsheetId, range).execute();
int numRows = result.getValues() != null ? result.getValues().size() : 0;
System.out.printf("%d rows retrieved.", numRows);

But again this is different to the code I already have so doesn't fit in as the getDataFromApi() method requires a return statement. I've tried just changing the spreadsheetId to that of my own spreadsheet and changing the range value to the cells I need,

/**
         * Fetch a list of names and majors of students in a sample spreadsheet:
         * https://docs.google.com/spreadsheets/d/1BxiMVs0XRA5nFMdKvBdBZjgmUUqptlbs74OgvE2upms/edit
         * @return List of names and majors
         * @throws IOException
         */
        private List<String> getDataFromApi() throws IOException {
            String spreadsheetId = "1-hL78Jm9-HijPx9UHthFxcXatkIhA2FR-AQ1lrCUbEg";
            String range = "Go Mix 12 0506!B6:D";
            List<String> results = new ArrayList<String>();
            ValueRange response = this.mService.spreadsheets().values()
                    .get(spreadsheetId, range)
                    .execute();
            List<List<Object>> values = response.getValues();
            if (values != null) {
                results.add("Name, Major");
                for (List row : values) {
                    results.add(row.get(1) + ", " + row.get(3));
                }
            }
            return results;
        }

but I'm clearly going about it wrong because I get this error: Invalid index 3, size is 3

I've also followed up to video 15 on this tutorial but it bypasses the need for any authorisation so didn't help.

Basically I've hit a brick wall and need someone to explain to me in simple terms how I can either work with the code from the quickstart tutorial to work with my own spreadsheet and fix that error! OR (more preferable to myself) explain how to do it myself from scratch. NB the spreadsheet cannot be public so I will need authorisation.

I hope that all makes sense!

回答1:

You are asking to retrieve three columns of data (B through D), but then attempting to read a fourth column (rows.get(3)). In Java (and in most programming languages), lists and arrays are 0-based. So if you want the first item, you call list.get(0), and if you want the third you call list.get(2). This is evident based on the fact that the error message tells you your index of 3 is invalid since the list is size 3 -- you're attempting to read something beyond the end of the list.

来源：https://stackoverflow.com/questions/45212295/using-the-google-sheets-api-after-completing-quickstart-tutorial