android Eventhandler like in c#

Hi, I just start developping on android and i'm missing the EventHandler from c#. As a learning process, I started to write an EventHandler in java. It's almost good execept the method:
getSlider_WantedValueChangedMethod()
I need to get it through reflection, and the name is a String. So when you refactor, It will not change. What do you think about it? Is there a better way?

Manu

EventHandler.java

import java.lang.reflect.InvocationTargetException;  
import java.lang.reflect.Method;  
import java.util.Vector;  
public class EventHandler<T extends EventArgs> {

    Vector<EventHandlerItem> subscribers = new Vector<EventHandlerItem>();

    public void Invoke(Object sender,T eventArgs) throws IllegalArgumentException, IllegalAccessException, InvocationTargetException {

        for (int i = 0, size = subscribers.size(); i < size; i++)
        {
            EventHandlerItem item = subscribers.get(i);
            item.Method.invoke(item.Subscriber,sender, eventArgs);
        }
    }

    public void add(Object subscriber,Method method) {
        subscribers.add(new EventHandlerItem(subscriber,method));
    }

    public void remove(Object subscriber) {
        subscribers.remove(subscriber);
    }
}

EventArgs

import java.util.EventObject;

public class EventArgs extends EventObject{
    private static final long serialVersionUID = 9202854783245818504L;

    public EventArgs(Object source) {
        super(source);

    }

}

EventArgs1

public class EventArgs1<T> extends EventArgs{

    private static final long serialVersionUID = -1694366721997799870L;

    private T property;
    public T getProp()
    {
     return property;
    }

    public EventArgs1(Object source,T property) {
        super(source);
        this.property = property;
    }
}

EventHandlerItem

import java.lang.reflect.Method;

final class EventHandlerItem {

    public Object Subscriber;
    public Method Method;

    public EventHandlerItem(Object subscriber,Method method)
    {
        this.Subscriber =subscriber;
        this.Method = method;
    }
}

slider

public EventHandler<EventArgs1<Double>> onWantedValueChanged = new EventHandler<EventArgs1<Double>>();
    private void InvokeWantedValueChanged(double value) throws Exception
    {
        onWantedValueChanged.Invoke(this,new EventArgs1<Double>(this,value));
    }
    public double getWantedValue()
    {
        return wantedValuePercent;
    }
    public void setWantedValue(double value)
    {
        if (wantedValuePercent == value) return;
        wantedValuePercent = value;
        try {
                InvokeWantedValueChanged(value);
        }
        catch (Exception ex){}
    }

Implementation

slider.onWantedValueChanged.add(this,getSlider_WantedValueChangedMethod());


private static Method slider_WantedValueChangedMethod;
    public Method getSlider_WantedValueChangedMethod() {
        if (slider_WantedValueChangedMethod != null)
            return slider_WantedValueChangedMethod;
        try {
            slider_WantedValueChangedMethod = getClass().getDeclaredMethod(
                    "slider_WantedValueChanged",Object.class, EventArgs1.class);
        } catch (Exception e) {
        }
        return slider_WantedValueChangedMethod;
    }
    public void slider_WantedValueChanged(Object sender,EventArgs1<Double> wantedValue) 
{
}

ansaurus

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android Eventhandler like in c#

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