[Solved]-Eclipse, new activity on button click-eclipse

add the code inside oncreate method like this in your preferencesactivity class:-

button button;
@override
protected void oncreate(bundle savedinstancestate) {
super.oncreate(savedinstancestate);

getsupportactionbar().setdisplayhomeasupenabled(true);
setcontentview(r.layout.activity_preferences);

donate = (imageview) findviewbyid(r.id.button_donate);
donate.setonclicklistener(new onclicklistener() {

    @override
    public void onclick(view v) {
        donate(v);
    }
});


button = (button) findviewbyid(r.id.button_visualhelp);
button.setonclicklistener(new onclicklistener() {
    public void onclick(view arg0) {
intent myintent = new intent(preferencesativity.this,
    visualhelpactivity.class);
    startactivity(myintent);
    }
});
spinner s = (spinner) findviewbyid(r.id.combo_language);
lang[] languages = languageutil.lang.values();

s.setadapter(new arrayadapter<lang>(this,
        android.r.layout.simple_dropdown_item_1line, languages));
s.setselection(getposition(languages, languageutil.getlanguage()), true);
}