Java Development

[njaa]

Hiho,

I have a problem with the following Code:

public class MyApp extends UiApplication
{    
    
    public static void main(String[] args)
    {
        MyApp app = new MyApp();
        app.enterEventDispatcher();
    }
    
    public MyApp()
    {                    
        if(System.getProperty("bluetooth.api.version") != null)
        {
            initializeMode();
        }
        else
        {          
            Dialog.alert("JSR 82 Bluetooth APIs not present");
            System.exit(0);            
        } 
    }
    
    private void initializeMode()
    {
    	System.out.println("INITIALIZE");
    	pushScreen(new ClientScreen());    
    }
}

public ClientScreen(int uuid)
{    	
        super(Manager.NO_VERTICAL_SCROLL);

        setTitle("...");
        
                 try {
            	
		 _local = LocalDevice.getLocalDevice();
		 _discoveryAgent = _local.getDiscoveryAgent();
	        } catch (BluetoothStateException e) {
		 e.printStackTrace();
	        }

       //startInquiry...
}

I start like in the BluetoothJSR82Demo with pushing a new Screen onto the stack. In the constructor I want to initiate a bluetooth device discovery.

Now the problem only appears when Bluetooth is disabled on the device at the beginning. So the getLocalDevice() command causes a Pop-Up that bluetooth has to be enabled. When the user chooses "yes"  then it takes round about 1 minute to enable it. The debugger output is like this:

[66988.26] BT: HCI_INITIALIZED
[66988.26] BT: EIR set
[66996.805] VM:+GC(f)w=11
[66997.4] VM:-GCt=76,b=1,r=0,g=f,w=11
[66997.43] VM:QUOT t=4
[66997.43] VM:+CR
[66997.445] VM:-CR t=2
[67010.97] JVM: bklt @67010968: timer
[67010.97] JVM: bklt[1] @67010968: usrIdle 23, usrTime 30, usrAct 1
[67010.97] JVM: bklt[1] @67010968: chkIdle 29, currTime 30
[67010.97] JVM: bklt @67010968: setTimer 7
[67017.96] JVM: bklt @67017960: timer
[67017.96] JVM: bklt[1] @67017960: usrIdle 30, usrTime 30, usrAct 1
[67017.96] JVM: bklt[1] @67017960: chkIdle 36, currTime 30
[67017.96] JVM: bklt[1] @67017960: enableBacklight 0
[67017.96] JVM: bklt[1]: setTimeout 30

When I use

UiApplication.getUiApplication().invokeLater(new Runnable()
{
   public void run() {
      pushScreen(new ClientScreen());
   }
});

instead,  the Pop-Up appears but the app crashes afterwards. So I can enable Bluetooth via the popup being in the homescreen.

I have to say I really have not understood when to use this invokeLater stuff so far.

Thanks in advance

njaa

[MSohm]

You should not use code in a screen's constructor that triggers a dialog.

If you want to initiate discovery on startup, perform that operation in a new thread you create in the screen's constructor.

[lyon819]

The sample does not work on BlackBerry 9900.

I modify the Github sample code, and then share to everyone.

https://sourceforge.net/projects/bluetoothjsr82d/

Cheers,