我正在尝试从SQLite数据库中获取数据库并尝试填充ListView
并在ArrayList<String>
中添加数据。 ListView
填充得很好,但问题是ArrayList<String>
没有很好地填充。
假设我在数据库中有数据,如:
一个
乙
C
d
Ë
F
G
H
一世
Ĵ
ķ
大号
中号
ñ
........
我的ListView
以这种方式显示数据。但ArrayList<String>
以这种方式添加数据:
一个
乙
C
d
Ë
F
一个
乙
C
d
Ë
F
G
H
......
这意味着我的ArrayList<String>
获得前6个值然后重复它然后接下来6个值然后再重复它.....这意味着当我从列表视图中单击项目“H”时,ArrayList<String>
会显示“B”。我不知道为什么会这样?
我的代码,CustomList,扩展CursorAdapter
import java.util.ArrayList;
import android.content.Context;
import android.database.Cursor;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.CheckBox;
import android.widget.CursorAdapter;
import android.widget.TextView;
public class CustomList extends CursorAdapter {
CheckBox favoriteBox;
TextView cityName, countryName;
ArrayList<String> city_name;
ArrayList<String> country_name;
ArrayList<String> country_short;
ArrayList<CheckBox> check_box;
public CustomList(Context context, Cursor c, ArrayList<String> city_name,
ArrayList<String> country_name, ArrayList<String> country_short,
ArrayList<CheckBox> check_box) {
super(context, c, 0);
this.city_name = city_name;
this.country_name = country_name;
this.country_short = country_short;
this.check_box = check_box;
}
@Override
public View newView(Context context, Cursor cursor, ViewGroup parent) {
LayoutInflater inflater = LayoutInflater.from(parent.getContext());
View retView = inflater.inflate(R.layout.all_city_list, parent, false);
return retView;
}
@Override
public void bindView(final View view, Context context, Cursor cursor) {
cityName = (TextView) view.findViewById(R.id.cityName);
String cityS = cursor.getString(cursor.getColumnIndex("city_name"));
cityName.setText(cityS);
city_name.add(cityS);//adding value to ArrayList<String>
countryName = (TextView) view.findViewById(R.id.countryName);
String conS = cursor.getString(cursor.getColumnIndex("country_name"));
countryName.setText(conS);
country_name.add(conS);//adding value to ArrayList<String>
country_short.add(""
+ cursor.getString(cursor.getColumnIndex("country_short")));//adding value to ArrayList<String>
favoriteBox = (CheckBox) view.findViewById(R.id.favoriteCheckBox);
check_box.add(favoriteBox);
if (cursor.getInt(cursor.getColumnIndex("favorite")) == 0) {
favoriteBox.setChecked(false);
} else {
favoriteBox.setChecked(true);
}
}
}
扩展AllCityListFragment
Fragment
import java.io.IOException;
import java.util.ArrayList;
import android.os.Bundle;
import android.os.Handler;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemLongClickListener;
import android.widget.CheckBox;
import android.widget.ListView;
import android.widget.Toast;
public class AllCityListFragment extends Fragment {
private CustomList customAdapter;
private DatabaseHelper databaseHelper;
ArrayList<String> city_name = new ArrayList<String>();
ArrayList<String> country_name = new ArrayList<String>();
ArrayList<String> country_short = new ArrayList<String>();
ArrayList<CheckBox> check_box = new ArrayList<CheckBox>();
public static final String ARG_OS = "OS";
int pos;
String sql = "";
ListView list;
View view;
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
view = inflater.inflate(R.layout.all_city_layout, null);
databaseHelper = new DatabaseHelper(view.getContext());
try {
databaseHelper.createDataBase();
databaseHelper.openDataBase();
} catch (IOException e) {
// TODO Auto-generated catch block
Toast.makeText(view.getContext(), "Error: " + e.getMessage(),
Toast.LENGTH_LONG).show();
e.printStackTrace();
}
list = (ListView) view.findViewById(R.id.citylist);
list.setFocusable(false);
list.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View myview,
int position, long id) {
Toast.makeText(getActivity(),
position + " " + city_name.get(position),
Toast.LENGTH_LONG).show();
}
});
sql = "SELECT _id, city_name, country_name, country_short, favorite FROM city order by country_name asc;";
new Handler().post(new Runnable() {
@Override
public void run() {
customAdapter = new CustomList(getActivity(), databaseHelper
.getResult(sql), city_name, country_name,
country_short, check_box);
list.setAdapter(customAdapter);
}
});
return view;
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
}
}
在这张照片中,我点击了“Shirajganj”,但是Toast
显示我“230 Thakurgaon”position = 230是正确的,但city_name.get(230)应该是“Shirajganj”。当我尝试在CustomList中的binView中向ArrayList<String>
添加值时,我认为这是错误的。我怎么解决这个问题?
答案 0 :(得分:0)
在bindView方法中填充该数组不是一个好主意。 Android不会为列表中的每一行创建单独的视图,它会利用已经创建的视图,这就是为什么你总会在你的arraylist中收到意想不到的结果的原因。最好是在活动中填充数组,而不是适配器。只需在数据库中查询相同的结果,如下所示:
Cursor cursor = getContentResolver().query(
uri,
projection,
selectionClause
selectionArgs,
sortOrder);
while (cursor.moveToNext ()){
arrayList.add(cursor.getAsString(cursor.getColumnIndex('column_name')));
}
cursor.close()