[SOLVED] ofxGui : update gui when value change?

This doesn't work for me.

Code:

parameters.add(waveOrigin.set("wave origin", ofVec2f(-0.5f, 0.0f), ofVec2f(-0.5f, -0.5f), ofVec2f(0.5f, 0.5f)));
waveOrigin.addListener(this, &shSharedResources::waveOriginListener);
void shSharedResources::waveOriginListener(ofVec2f& _value)
{
float wox = _value.x;
float woy = _value.y;
int woxi = (int)(wox * 10.0f);
int woyi = (int)(woy * 10.0f);
_value.x = (float)woxi / 10.0f;
_value.y = (float)woyi / 10.0f;
waveOrigin.set(_value);
}

I went and set a breakpoint to see if it got in the function, and it does perform that function. However, it does not update the GUI.

UPDATE: I figured it out, you can't get edit values of a ofParameter from it's listener function. Makes sense, really.