You don't need OnSharedPreferenceChangeListener in this case. What you need is to override onHeaderClick method in your PreferenceActivity.
@Override
public void onHeaderClick(Header header, int position) {
super.onHeaderClick(header, position);
if (header.id == R.id.clear_cache) {
clearApplicationData();
}
}
Of course you have to add an id to header in xml.
<header android:id="@+id/clear_cache"
android:icon="@drawable/ic_action_cancel"
android:title="Vider le cache d'articles"
android:key="clearCache"
android:summary="Clear all datas.">
</header>