Uncaught RefferenceError of global array in javascript

Question

I have script in A.js like this:

function sinkronMyDB(){
    sinkronDB();
    var u_name = window.localStorage.getItem('uname');
    if(dataSync.length !== 0){ // <-- line 4
        var dataSinkronItems = [];
        for (var i = 0; i<dataSync.length; i++) {
            dataSinkronItems[i] = dataSync[i];
            console.log('dataSync('+i+') = '+dataSync[i]);
        };
        $.ajax({
            url:'http://qrkonfirmasi.16mb.com/delivery/update.php',
            data: {data : dataSinkronItems, username: u_name}, 
            type:'post',
            async:'false',
            dataType: 'json',
            beforeSend:function(){
                $.mobile.loading('show',{theme:"a",text:"Update...",textonly:true,textVisible:true});
            },
            complete:function(){
                $.mobile.loading('hide');
            },
            success:function(result){
                if (result.status===true) {
                    dataBaru = [];
                    idBaru = [];
                    for (i=0; i<dataBaru.length; i++){
                        dataBaru[i] = result.dataBaru[i];
                        idBaru[i] = result.id[i];
                    }
                    sinkronUpd();
                    console.log('Database update success.');
                } else{
                    console.log('Tidak ada pengiriman baru.');
                }
            },
            error:function(request,error){
                alert('Koneksi error. Silahkan coba beberapa saat lagi!');
            }
        });
    }else alert('Belum ada barang yang terkirim');
}

function sinkronDB() is in another Script file. lets call it B.js. the script content is like this:

function sinkronDB(){
    db.transaction(sinkronQuery,errorCB);
}

function sinkronQuery(tx){
    tx.executeSql("SELECT * FROM data_pengiriman WHERE Status = 'Terkirim'",[],successSelect);
}

function successSelect(tx,result){
    var len = result.rows.length;
    dataSync = [];
    for (var i=0; i<len; i++){
        dataSync[i] = result.rows.item(i).id_pengiriman;
        console.log('dataSync['+i+'] = '+dataSync[i]);
    }
}

In console log it's say error:

Uncaught ReferenceError: dataSync is not defined at file A.js line 4.

I tried check it with jshint and no error. Can anyone help me solve it, please!

Arun P Johny · Accepted Answer · 2015-08-06 07:09:26Z

1

The problem is sinkronDB is asynchronous, so the if statement is evaluated before sinkronDB is completed

So you need to use a callback to handle the response like

function sinkronDB(callback) {
    db.transaction(function (tx) {
        sinkronQuery(tx, callback)
    }, errorCB);
}

function sinkronQuery(tx, callback) {
    tx.executeSql("SELECT * FROM data_pengiriman WHERE Status = 'Terkirim'", [], function (tx, result) {
        successSelect(tx, result, callback);
    });
}

function successSelect(tx, result, callback) {
    var len = result.rows.length;
    var dataSync = [];
    for (var i = 0; i < len; i++) {
        dataSync[i] = result.rows.item(i).id_pengiriman;
        console.log('dataSync[' + i + '] = ' + dataSync[i]);
    }
    callback(dataSync)
}

then

function sinkronMyDB() {
    sinkronDB(function (dataSync) {
        var u_name = window.localStorage.getItem('uname');
        if (dataSync.length !== 0) { // <-- line 4
            var dataSinkronItems = [];
            for (var i = 0; i < dataSync.length; i++) {
                dataSinkronItems[i] = dataSync[i];
                console.log('dataSync(' + i + ') = ' + dataSync[i]);
            };
            $.ajax({
                url: 'http://qrkonfirmasi.16mb.com/delivery/update.php',
                data: {
                    data: dataSinkronItems,
                    username: u_name
                },
                type: 'post',
                async: 'false',
                dataType: 'json',
                beforeSend: function () {
                    $.mobile.loading('show', {
                        theme: "a",
                        text: "Update...",
                        textonly: true,
                        textVisible: true
                    });
                },
                complete: function () {
                    $.mobile.loading('hide');
                },
                success: function (result) {
                    if (result.status === true) {
                        dataBaru = [];
                        idBaru = [];
                        for (i = 0; i < dataBaru.length; i++) {
                            dataBaru[i] = result.dataBaru[i];
                            idBaru[i] = result.id[i];
                        }
                        sinkronUpd();
                        console.log('Database update success.');
                    } else {
                        console.log('Tidak ada pengiriman baru.');
                    }
                },
                error: function (request, error) {
                    alert('Koneksi error. Silahkan coba beberapa saat lagi!');
                }
            });
        } else alert('Belum ada barang yang terkirim');
    });
}

answered Aug 6, 2015 at 7:09

Arun P Johny

389k68 gold badges532 silver badges532 bronze badges

Sign up to request clarification or add additional context in comments.

6 Comments

Mahfud Muhammad Over a year ago

thanks it's fixed. but cant u check my code again in B.js. it's always result alert('Koneksi error. Silahkan coba beberapa saat lagi!'). it means cant connect to server caused by connection error. but i try login function it works well. and in console no error sign.

Mahfud Muhammad Over a year ago

By the way this is sinkronUpd():

function sinkronUpd(){     db.transaction(updQuery,errorCB); }  function updQuery(tx){     var len = dataBaru.length;     for (var i = 0; i < len; i++) {         tx.executeSql("INSERT OR IGNORE INTO data_pengiriman VALUES ('"+idBaru[i]+"', '"+dataBaru[i]+"', 'Belum Terkirim')");         console.log('Inserted new kode '+dataBaru[i]+ ' id: ' +idBaru[i]+'.');     } }

Arun P Johny Over a year ago

@MahfudMuhammad add alert(error) in the error handler to see the error

Mahfud Muhammad Over a year ago

it says parsererror. but i use the same way of json parsing in login and it worked well.

Arun P Johny Over a year ago

@MahfudMuhammad what is the value returned... can you check the browser's network tab to check the returned value... since you have set dataType: 'json' you need to return a proper json response.. which seems to be not happening

|

Swaraj Giri · Accepted Answer · 2015-08-06 07:07:03Z

0

As the error message says, you have not defined dataSync. Define it, var dataSync = []; and push whatever you need to it.

answered Aug 6, 2015 at 7:07

Swaraj Giri

4,0372 gold badges30 silver badges45 bronze badges

1 Comment

Mahfud Muhammad Over a year ago

i suppose to make a global array. so where should i define it?

iplus26 · Accepted Answer · 2015-08-06 07:11:04Z

0

You have defined dataSync inside successSelect(tx,result) method, and it is not a global variable. sinkronMyDB() method has no access to it.

If you want to make it a global array, put var dataSync = [] outside the functions, and make sure successSelect(tx,result) method is executed before sinkronMyDB() method.

answered Aug 6, 2015 at 7:11

iplus26

2,68618 silver badges26 bronze badges

Collectives™ on Stack Overflow

Uncaught RefferenceError of global array in javascript

3 Answers 3

6 Comments

1 Comment

Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

6 Comments

1 Comment

Comments

Your Answer

Sign up or log in

Post as a guest

Related