BarcodeScanner2 = TypeError: Cannot set property 'innerHTML' of null

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I am trying to develop a barcode scanning app using phonegap-1.4.1 in android. I am trying to store all the values in an array code[] and later on I am displayi

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一生所求

2021-01-16 12:40

Add below javascript Function in your html file ( top of the page).

function SaveDataToLocalStorage(barcodeValue)
{

    var oldItems = JSON.parse(localStorage.getItem('barcodes')) || [];
    var newItem = {
        'barcode': barcodeValue
    };
    oldItems.push(newItem);
    localStorage.setItem('barcodes', JSON.stringify(oldItems));

}

Now Change Your barcode Scan Code as below :

var scanCode = function () {
      window.plugins.barcodeScanner.scan(function (result) {
         if(result.cancelled == true ) {
           window.location.href = 'page5.html';
         } else {
           // below function save your data in localstorage.
           SaveDataToLocalStorage(result.text);
           scanCode();
         }

     }, function (error) {
            alert("Scan failed: " + error);
           window.location.href = 'page5.html';
    });
  }

Now, if you want to display all barcodes in page5.html just read all barcodes from localstorage and display it in page.

use following function page5.html to display all barcodes in page5.html

function displayValues()
{
    var oldItems = JSON.parse(localStorage.getItem('barcodes')) || [];

    for(var i=oldItems.length-1;i>=0;i--)
    {
        var html=document.getElementById("allCodes").innerHTML;
        document.getElementById("allCodes").innerHTML=html+"<br>"+oldItems[i].barcode;      
    }    
}

make one div name allCodes in page5.html

Your page5.html

<body>
<div id="allCodes">

</div>

</body>
<script>
function displayValues()
{
    var oldItems = JSON.parse(localStorage.getItem('barcodes')) || [];

    for(var i=oldItems.length-1;i>=0;i--)
    {
        var html=document.getElementById("allCodes").innerHTML;
        document.getElementById("allCodes").innerHTML=html+"<br>"+oldItems[i].barcode;      
    }    
    }
displayValues();
</script>

//Display in table :

function displayValues()
{
    var oldItems = JSON.parse(localStorage.getItem('barcodes')) || [];

    if(oldItems.length>0)
    {
        document.getElementById("allCodes").innerHTML="<table border='2'>";
    }
    for(var i=oldItems.length-1;i>=0;i--)
    {
        var html=document.getElementById("allCodes").innerHTML;
        html=html+"<tr><td>"+oldItems[i].barcode+"</td></tr>";
        document.getElementById("allCodes").innerHTML=html;   
    }    
    if(oldItems.length>0)
    {
        var old=document.getElementById("allCodes").innerHTML;
        document.getElementById("allCodes").innerHTML=old+"</table>"

    }
}

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慢半拍i

2021-01-16 12:40

The error is clearly related to document.getElementById(test2[k]) returning no element, hence, there is no element with the id given. In your sample this would be Test1.

Set the id of the paragraph to Test1 instead of Text and it find the element.

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