我想打印ArrayList
。我已经从类AsyncTask
接收值arraylist,在MainActivity
,我有值ArrayList,但是当我打印ArrayList时,我的应用程序不工作。请帮帮我!如何从类AsyncTask打印arraylist?
MainActivity
{
executeLoadProduct();
arraylistgroup = new ArrayList<String>();
arraylistgroup=TaskLoadProductGroup.getvaluearraylist();
String[] mStringArray = new String[arraylistgroup.size()];
mStringArray = arraylistgroup.toArray(mStringArray);
for (int i = 0; i < mStringArray.length; i++) {
System.out.println("string is2" + (String) mStringArray[i]);
}
executeLoadProduct
private void executeLoadProduct() {
// execute task load product
loadProductGroup = new TaskLoadProductGroup(MainActivity.this);
loadProductGroup.execute();
}
的AsyncTask
public class TaskLoadProductGroup extends AsyncTask<String, Void, ArrayList<String>> {
private ActionBarActivity actionBarActivity;
private Context context;
private static ArrayList<String> arrayListgroup;
public TaskLoadProductGroup(ActionBarActivity actionBarActivity) {
this.actionBarActivity = actionBarActivity;
this.context = actionBarActivity.getApplicationContext();
}
@Override
protected void onPreExecute() {
///show progress loading
super.onPreExecute();
}
@Override
protected ArrayList<String> doInBackground(String... url) {
ArrayList<String> listProductgroup = null;
try {
Server server = new Server();
ResListProduct resListProduct = server.getListProducts(context);
//init list item for listview home product
listProductgroup = initItemProduct(resListProduct);
} catch (Exception e) {
}
return listProductgroup;
}
public static ArrayList<String> initItemProduct(ResListProduct rsProduct) {
List<GroupProduct> groups = rsProduct.getGroups();
arrayListgroup = new ArrayList<String>();
for (GroupProduct group : groups) {
// add header group
String s = group.getName();
arrayListgroup.add(s);
}
getvaluearraylist();
// getVarialty();
return arrayListgroup;
}
public static ArrayList<String> getvaluearraylist()
{
return arrayListgroup;
}
@Override
protected void onPostExecute(ArrayList<String> listProductgroup) {
super.onPostExecute(listProductgroup);
}
}
这是你在'mainactivity.java'中尝试打印你的数组吗? –
我想打印类TaskLoadProductGroup的arrayListgroup。 –
然后当您尝试从doInBackground打印时发生了什么?您是否尝试使用Log类进行打印或在设备的屏幕上进行打印? –