Question

I am adding the device list to the ArrayAdapter and show it in ListView, where device list is getting from the Bluetooth scan, the scanned devices first add to the arrayadapter. Then later i am adding it to the listview to show the list of scanned bluetooth devices to user.

But when i am scanning for the devices, duplicate device is adding, suppose a device A is scanned means then again two or three times its showing device A. I want to show the list of scanned device only one time. How to achieve it. Sorry if question is vague.

Following code is for enquire new devices and adding it to arrayadapter:

if (BluetoothDevice.ACTION_FOUND.equals(action))
        {
            // Get the BluetoothDevice object from the Intent
            BluetoothDevice device = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);
            // If it's already paired, skip it, because it's been listed already
            if (device.getBondState() != BluetoothDevice.BOND_BONDED)
            {
                mNewDevicesArrayAdapter.add(device.getName() + "\n" + device.getAddress());
            }
        // When discovery is finished, change the Activity title
        } else if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)) {
            setProgressBarIndeterminateVisibility(false);
            setTitle(R.string.select_device);
            if (mNewDevicesArrayAdapter.getCount() == 0) {
                String noDevices = getResources().getText(R.string.none_found).toString();
                mNewDevicesArrayAdapter.add(noDevices);
            }
        }

Its an program in Android example of version 4.1, example name is Bluetooth Chat. Where activity is DeviceListActivityScan.java.

Answer 1

I run this demo in my two phones, only one will scan multiple times.
so i guess it is relating to the devices.

u can do that to avoid it:

            if (device.getBondState() != BluetoothDevice.BOND_BONDED) {
                String deviceInfo = device.getName() + "\n" + device.getAddress();
                if(mNewDevicesArrayAdapter.getPosition(deviceInfo) < 0) {
                    mNewDevicesArrayAdapter.add(deviceInfo);
                }
            }