How can I lock the keypad in Blackberry application using "lockSystem" method in J2ME?

How can I lock the keypad in Blackberry application u开发者_高级运维sing "lockSystem" method in J2ME ?? And also the brightness of the blackberry should reduce to Zero ??

its really easy. I know the answer. We can just use the method "lockSystem". I have coded as following to lock the keypad. It takes long time for me to find it, but u got this.

package net.asem;
import net.rim.device.api.system.ApplicationManager;
import net.rim.device.api.ui.Field;
import net.rim.device.api.ui.FieldChangeListener;
import net.rim.device.api.ui.UiApplication;
import net.rim.device.api.ui.component.ButtonField;
import net.rim.device.api.ui.component.LabelField;
import net.rim.device.api.ui.container.MainScreen;


public class LockBlackberry extends UiApplication
{
    public static void main(String[] args) 
    {
        LockBlackberry lockB = new LockBlackberry();
        lockB.enterEventDispatcher();
    }
    LockBlackberry()
    {
        pushScreen(new myBlackBerryClass());

    }
}
final class myBlackBerryClass extends MainScreen implements FieldChangeListener<br>
{
    LabelField title;
    ButtonField btn1;
    myBlackBerryClass()
    {
        LabelField title = new LabelField("Title : Locking the Device.",LabelField.USE_ALL_WIDTH | LabelField.USE_ALL_WIDTH);
        setTitle(title);
        btn1 = new ButtonField("KeyPad Loack ?",ButtonField.CONSUME_CLICK);
        btn1.setChangeListener(this);
        add(btn1);
    }
    public void fieldChanged(Field field, int context)
    {
        if(field == btn1)
        {
         Click();
        }

    }
    private void Click()
    {
        ApplicationManager manager = ApplicationManager.getApplicationManager();
        manager.lockSystem(true);
    }

}