Receive broadcast data from external barcode scanner

[ghost]

Hi, is it possible to retrieve the data globally (because i have many input from the pages) when a hardware scanner captured the barcode? I have tested the sample code from the documentation but it does not work.

[bsorrentino]

Hi, is it possible to retrieve the data globally (because i have many input from the pages) when a hardware scanner captured the barcode? I have tested the sample code from the documentation but it does not work.

Hi @JustonJ99

I need more details.

• is it possible to retrieve the data globally?

  What does it mean ? The data is sent in an event handler

• I have tested the sample code from the documentation but it does not work.

  do u mean not work handling of barcode ?

[kmitdebus]

I think I get the same error ("its not working with external reader")

My Code:

window.broadcaster.addEventListener( 'de.someExternalBroadcast.SCAN_DATA', true, function( e ) { console.log( e ); });

broadcaster.js:84 Uncaught TypeError: Cannot set property type of #<Event> which has only a getter at Broadcaster.fireEvent (broadcaster.js:84:30) at <anonymous>:1:20

Broadcasted data is: {data: "25C6AE3E", secondaryData: null, type: "#41", typeExt: "HiTag1/S"}

[bsorrentino]

Hi @kmitdebus thanks for sharing infos, I'll investigate as soon as possible

[lgl017]

I think I get the same error ("its not working with external reader")

My Code:

window.broadcaster.addEventListener( 'de.someExternalBroadcast.SCAN_DATA', true, function( e ) { console.log( e ); });

broadcaster.js:84 Uncaught TypeError: Cannot set property type of #<Event> which has only a getter at Broadcaster.fireEvent (broadcaster.js:84:30) at <anonymous>:1:20

Broadcasted data is: {data: "25C6AE3E", secondaryData: null, type: "#41", typeExt: "HiTag1/S"}

I get the same error too, i find the issue in js code:

Broadcaster.prototype.fireEvent = function (type, data) {
        if (!this._channelExists(type))
            return;
        var event = document.createEvent('Event');
        event.initEvent(type, false, false);
        if (data) {
            for (var i in data) {
                if (data.hasOwnProperty(i)) {
                    event[i] = data[i];
                  //^^^ will error when key is "type", "type" in event object is readonly
                }
            }
        }
        this._channelFire(event);
    };

to fix that, special handling key "type" to another

[bsorrentino]

Hi @lgl017 thanks for valuable feedback

Now there is another issue .... what's the best way to handle such problem:

1. catch error and ignore it ( simplest )
2. rename data.type property in event.dataType
3. throw a more meaningful exception

I prefer the n. 2 what do you think ?

[bsorrentino]

I think I get the same error ("its not working with external reader") My Code: window.broadcaster.addEventListener( 'de.someExternalBroadcast.SCAN_DATA', true, function( e ) { console.log( e ); }); broadcaster.js:84 Uncaught TypeError: Cannot set property type of #<Event> which has only a getter at Broadcaster.fireEvent (broadcaster.js:84:30) at <anonymous>:1:20 Broadcasted data is: {data: "25C6AE3E", secondaryData: null, type: "#41", typeExt: "HiTag1/S"}

I get the same error too, i find the issue in js code:

Broadcaster.prototype.fireEvent = function (type, data) {
       if (!this._channelExists(type))
           return;
       var event = document.createEvent('Event');
       event.initEvent(type, false, false);
       if (data) {
           for (var i in data) {
               if (data.hasOwnProperty(i)) {
                   event[i] = data[i];
                 //^^^ will error when key is "type", "type" in event object is readonly
               }
           }
       }
       this._channelFire(event);
   };

to fix that, special handling key "type" to another

I've updated the fireEvent code

Broadcaster.prototype.fireEvent = function (type, data) {
        if (!this._channelExists(type))
            return;
        var event = new Event(type, { bubbles: false, cancelable: false });
        if (data) {
            event['data$'] = data; // fix issue #67
            // for backward compatibility
            for (var i in data) {
                if (data.hasOwnProperty(i) && event[i] === undefined) {
                    event[i] = data[i];
                }
            }
        }
        this._channelFire(event);
}

The solution is to store the given data object in a new Event.data$ property. For backward compatibility the data properties will be added to Event object skipping the ones already present in Event itself. So in the case of type clashing to retrieve type value we have to access the data property:

// in the listener 
    var listener = function( e ) {
      console.log( "type:  ", e.data$.type  );
    }

[bsorrentino]

fix released in 5.2.0