894356 - [B2G][Helix][Bluetooth]BT in eng-mode only can search one device when there are many BT devices nearby

Status: RESOLVED INVALID

(Firefox OS Graveyard :: Bluetooth, defect)

Description

[ouyangming]

User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0; SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media Center PC 6.0; aff-kingsoft-ciba; .NET4.0C; .NET4.0E)

Steps to reproduce:

When we do the BT test in eng-mode, we open the BT and get the defaultAdapter,then begin to search the BT device. The code as following:
      var requestres = defaultAdapter.startDiscovery();
      defaultAdapter.ondevicefound = function get_result(evt)
      {
	var device = evt.device;
	document.write(device.address);
	document.write("<br>");
      }
    Function ondevicefound will be called when found the BT device. 
         


Actual results:

The function ondevicefound only be called once when there are many BT devices nearby. It means in eng-mode we can only search one BT device when there are many BT devices nearby.


Expected results:

The function ondevicefound should be called many times when there are many BT devices nearby.

Comment 1

[Shawn Huang [:shawnjohnjr][:shuang] (as a happy gecko contributor)]

Dear Vincent,
Can you help to update test results on Helix?

Comment 2

[Shawn Huang [:shawnjohnjr][:shuang] (as a happy gecko contributor)]

Confirmed with our member, this bug can be reproduced on Helix with eng-mode. Currently it does not look like gecko problem. So :ehung will help on it further for eng-mode.

Comment 3

[Evelyn Hung]

(In reply to ouyangming from comment #0)
> User Agent: Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 6.1; Trident/4.0;
> SLCC2; .NET CLR 2.0.50727; .NET CLR 3.5.30729; .NET CLR 3.0.30729; Media
> Center PC 6.0; aff-kingsoft-ciba; .NET4.0C; .NET4.0E)
> 
> Steps to reproduce:
> 
> When we do the BT test in eng-mode, we open the BT and get the
> defaultAdapter,then begin to search the BT device. The code as following:
>       var requestres = defaultAdapter.startDiscovery();
>       defaultAdapter.ondevicefound = function get_result(evt)
>       {
> 	var device = evt.device;
> 	document.write(device.address);
> 	document.write("<br>");
The root cause is simply because of the |document.write| here.
After document loaded, |document.write| will clear all DOM content, in fact, on Firefox, its behavior is more like creating a new page. So all JavaScript objects are cleared includes defaultAdapter. That's why after the first entry is written, it gets stuck.