嘿我無法聲明,更改和使用全局變量。我嘗試了整個「創建一個擴展你的應用程序並把變量放在那裏的類」的東西,但我不知道如何實現它。這是我的課程,其中的變量。在Android應用程序中遇到困難與全局變量
public class MyApp extends Application {
public int listPos;
}
然後我嘗試訪問並更改int listPos在這裏。
public class Browse extends ListActivity{
MyApp app = ((MyApp)getApplicationContext());
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
String[] coffeeTypes = getResources().getStringArray(R.array.coffeeTypes);
setListAdapter(new ArrayAdapter<String>(this, R.layout.listview, coffeeTypes));
ListView lv = getListView();
lv.setTextFilterEnabled(true);
lv.setOnItemClickListener(new OnItemClickListener() {
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
app.listPos = position;
startActivity(new Intent(Browse.this, CoffeeTypes.class));
}
});
}
}
然後我試圖訪問該變量在下面的活動來決定的,如果else語句
public class CoffeeTypes extends Activity{
MyApp app = ((MyApp)getApplicationContext());
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if(app.listPos == 0){
Toast.makeText(this, "WEEEEEEE!0", Toast.LENGTH_LONG).show();
}
else if(app.listPos == 1){
Toast.makeText(this, "RAWR!1", Toast.LENGTH_LONG).show();
任何人有任何想法,我做錯了的結果?
實際問題是什麼? – Haphazard 2011-04-28 01:07:11