Question

    this.init = function (onupgradeneeded, onsuccess) {

        var openRequest = indexedDB.open(dbName);

        openRequest.onupgradeneeded = function (e) {

            db = e.target.result;

            if (!db.objectStoreNames.contains(objectStoreName)) {

                console.log('Creating the ' + objectStoreName + ' objectstore');

                db.createObjectStore(objectStoreName, { keyPath: "id", autoIncrement: true });

            }

        };

        openRequest.onsuccess = function (e) {

            db = e.target.result;

            db.onerror = function (event) {
                // Generic error handler for all errors targeted at this database requests
                console.log("Database error: " + event.target.errorCode);
            };
        };

    };

Called by:

var idb = new Demo.IndexedDB();
idb.init();

When the init function runs, it will either end up in openRequest.onupgradeneeded or openRequest.onsuccess.

What i would like to know is if its possible to create a generic callback function that gets called in both function. So regardless of which of the two functions that runs i can know when theyre done by using

idb.init(function(){
    //onupgradeneeded or onsuccess completed
});

Hope you get the idea, otherwise ill elaborate.

Thanks

Answer 1

Just pass in one callback function and call that one single callback in both cases:

this.init = function (onFinish) {

    var openRequest = indexedDB.open(dbName);

    openRequest.onupgradeneeded = function (e) {

        db = e.target.result;

        if (!db.objectStoreNames.contains(objectStoreName)) {

            console.log('Creating the ' + objectStoreName + ' objectstore');

            db.createObjectStore(objectStoreName, { keyPath: "id", autoIncrement: true });

        }
        onFinish();

    };

    openRequest.onsuccess = function (e) {

        db = e.target.result;

        db.onerror = function (event) {
            // Generic error handler for all errors targeted at this database requests
            console.log("Database error: " + event.target.errorCode);
        };
        onFinish();
    };

};