WinJS SQLite runAsync all before doing something else

问题

I have a collection of INSERT statements that gets run within a SQLite async method:

SQLite3JS.openAsync(path).then(function (db) {
    $.each(sql, function (idx, item) {
        return db.runAsync(item).done(function complete(xhr) {
            var i = 0;
        });
    });
});

I want the collection to be inserted, then do something after this has completed successfully. I tried to follow through on then() promises, but they all get called before the db.runAsync() gets fired.

Is there a clean way to do this? Basically, I have a progress ring that should be removed once all this has completed, but I cannot get this to fire correctly.

回答1:

I think you'll want to use WinJS's ability to join multiple promises together...

SQLite3JS.openAsync(path).then(function (db) {
    var promises = [];
    $.each(sql, function (idx, item) {
        promises.push( db.runAsync(item) );
    });

    return WinJS.Promis.join( promises ).then(
        function success() {
            // all done!
        },
        function error() {
            // something didn't work
        },
    );
});

来源：https://stackoverflow.com/questions/20803684/winjs-sqlite-runasync-all-before-doing-something-else