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POJava Scoping with ActionListeners
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copied!<p>I have an application that needs to scan for bluetooth devices every 10 minutes for a duration set by the user. </p> <p>I have two javax.swing.Timer (not java.util.Timer) - one controls invoking the Scanning method every 10 minutes, the other is stopping the first timer (therfore stopping the scanning) once the duration limit has been hit. </p> <p>The durationTimer is created and started within an actionListener. </p> <p>My problem is that because durationTimer is created within an ActionListener, i cannot stop the timer from another ActionListener, as the program cannot "see" the variable name "durationTimer". </p> <p>The reduced code is shown below....</p> <pre><code>public class mainGui extends JFrame { public mainGui() { final ActionListener timerActionEvent = new ActionListener(){ public void actionPerformed(ActionEvent evt){ //start a task here Timer myTimer2 = (Timer) evt.getSource(); //Invoke BluetoothScan method BluetoothScan(myTimer2); } }; final Timer timerDuration; final Timer myTimer = new Timer(5000, timerActionEvent); final ActionListener timerDurationActionEvent = new ActionListener(){ public void actionPerformed(ActionEvent evt){ //Stops myTimer, so that Bluetooth Stops scanning every 10mins. myTimer.stop(); } }; ActionListener btnScanAction = new ActionListener(){ //Action listener for reading data from db public void actionPerformed(ActionEvent e){ int roomID = 0; int lecturer = 0; int unit; int roomIDIndex; int lectIDIndex; int yearIDIndex; int unitIDIndex; String[] roomArray; String[] lecturerArray; String[] unitArray = null; int durationIndex; String DURATION; int durationInt; //System.out.println(unitArray.length); durationIndex = durCB.getSelectedIndex(); DURATION = itemDuration[durationIndex]; durationInt = Integer.parseInt(DURATION); //User Selected Duration converted to Milliseconds int durationMilliSec = (int)(durationInt*60000); ArrayList<String[]> unitYear = null; //Store the index ID of the JComboBox Selections roomIDIndex = roomCB.getSelectedIndex(); lectIDIndex = lectCB.getSelectedIndex(); unitIDIndex = unitCB.getSelectedIndex(); yearIDIndex = yearCB.getSelectedIndex(); switch(yearIDIndex) { case 1: unitYear = Units1; break; case 2: unitYear = Units2; break; case 3: unitYear = Units3; break; case 4: unitYear = UnitsMasters; break; } //Get the Array contents at index location roomArray = rooms.get(roomIDIndex); lecturerArray = Lecturers.get(lectIDIndex); unitArray = unitYear.get(unitIDIndex); if(unitArray==null){ System.out.println("Please select a unit"); System.exit(0); } roomID = Integer.parseInt(roomArray[0]); lecturer = Integer.parseInt(lecturerArray[0]); unit = Integer.parseInt(unitArray[0]); populateComboBoxes pcb = new populateComboBoxes(); pcb.LabSessionInfo(roomID, lecturer, unit); myTimer.start(); Timer timerDuration = new Timer(durationMilliSec, timerDurationActionEvent); timerDuration.start(); } }; public void BluetoothScan(Timer myTimer) { BluetoothDeviceDiscovery scan = new BluetoothDeviceDiscovery(); try { myTimer.stop(); scan.main(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (InterruptedException e) { // TODO Auto-generated catch block e.printStackTrace(); } myTimer.start(); }; } </code></pre> <p>Thankyou in advance for any help</p>

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