从回调函数调用其他函数

Question

I like to have some help... being stuck with this for a while.

var inventoryID = '123456';

function pickupFail(){
    db = window.openDatabase("myInvetory", "1.0", "myInvetory", 200000);
    db.transaction(queryUpdateInventory, dbError);
}

function queryUpdateInventory(tx){
    var sql = "SELECT inventoryCount FROM Inventory WHERE inventoryID = ?";
    tx.executeSql(sql, [inventoryID], finalizeUpdateInventory, dbError);
}

function finalizeUpdateInventory(tx, results){
   ....
   var inventoryCount = 0;
   var inventory = results.rows.item(0);
   ....
   inventoryCount = inventory.count;
   ....
   ....
   otherFunction(inventoryCount); // CALLING THIS PRODUCE CALLBACK ERROR
   ....
}

function otherFunction(count,...){
   ....
   //THIS IS LENGTHILY FUNCTION AND BEING USED BY OTHER FUNCTION AS WELL

}

Frankly said, I'm very novice on Cordova and javascript callback concept. I really do appreciate help from you guys.

Answer 1

You are calling a function and defining it later. Defining otherFunction(count) before finalizeUpdateInventory() should remove the error. So the modified code becomes:

var inventoryID = '123456';

function pickupFail(){
    db = window.openDatabase("myInvetory", "1.0", "myInvetory", 200000);
    db.transaction(queryUpdateInventory, dbError);
}

function queryUpdateInventory(tx){
    var sql = "SELECT inventoryCount FROM Inventory WHERE inventoryID = ?";
    tx.executeSql(sql, [inventoryID], finalizeUpdateInventory, dbError);
}

function otherFunction(count,...){
   ....
   //THIS IS LENGTHILY FUNCTION AND BEING USED BY OTHER FUNCTION AS WELL

}

function finalizeUpdateInventory(tx, results){
   ....
   var inventoryCount = 0;
   var inventory = results.rows.item(0);
   ....
   inventoryCount = inventory.count;
   ....
   ....
   otherFunction(inventoryCount); // CALLING THIS PRODUCE CALLBACK ERROR
   ....
}

Answer 2

I finally found the error inside otherFunction. It seems that otherFunction is calling html element that not exist in that same page. This html element exist in other pages that use otherFunction.