虽然这里已经多次询问过这个问题，但我找不到合适的答案来适应我的代码。我意识到它可能很小，但我似乎无法找到问题，因为我只是真的很新。
以下是 DatabaseHelper 类中的代码 getClientNames ：
public Cursor getSitesByClientname(String id) {
String[] args={id};
Cursor myCursor = db.rawQuery("SELECT client_sitename FROM " + CLIENT_SITES_TABLE + " WHERE client_id=?", args);
String results = "";
/*int count = myCursor.getCount();
String[] results = new String[count + 1];
int i = 0;*/
if (myCursor != null) {
if(myCursor.getCount() > 0)
{
for (myCursor.moveToFirst(); !myCursor.isAfterLast(); myCursor.moveToNext())
{
results = results + myCursor.getString(myCursor.getColumnIndex("client_sitename"));
}
}
}
return results;
}
一个问题是我正在向'Cursor'返回一个'String'，但是我不确定这是什么最好的方法，因为我认为我应该返回一个Cursor。
以下是我要显示数据的 ClientSites 类：
public class ClientSites extends Activity {
//public final static String ID_EXTRA="com.example.loginfromlocal._ID";
private DBUserAdapter dbHelper = null;
private Cursor ourCursor = null;
private Adapter adapter=null;
@SuppressWarnings("deprecation")
@SuppressLint("NewApi")
public void onCreate(Bundle savedInstanceState) {
try
{
super.onCreate(savedInstanceState);
setContentView(R.layout.client_sites);
Intent i = getIntent();
String uID = String.valueOf(i.getIntExtra("userID", 0));
ListView myListView = (ListView)findViewById(R.id.myListView);
dbHelper = new DBUserAdapter(this);
//dbHelper.createDatabase();
dbHelper.openDataBase();
ourCursor = dbHelper.getSitesByClientname(uID);
Log.e("ALERT", uID.toString());
startManagingCursor(ourCursor);
Log.e("ERROR", "After start manage cursor: ");
//@SuppressWarnings("deprecation")
//SimpleCursorAdapter adapter = new SimpleCursorAdapter(getBaseContext(), R.id.myListView, null, null, null);
CursorAdapter adapter = new SimpleCursorAdapter(this, R.id.myListView, null, null, null, 0);
adapter = new Adapter(ourCursor);
//Toast.makeText(ClientSites.this, "Booo!!!", Toast.LENGTH_LONG).show();
myListView.setAdapter(adapter);
myListView.setOnItemClickListener(onListClick);
}
catch (Exception e)
{
Log.e("ERROR", "XXERROR IN CODE: " + e.toString());
e.printStackTrace();
}
}
private AdapterView.OnItemClickListener onListClick=new AdapterView.OnItemClickListener() {
public void onItemClick(AdapterView<?> parent,
View view, int position,
long id)
{
Intent i=new Intent(ClientSites.this, InspectionPoints.class);
i.putExtra(ID_EXTRA, String.valueOf(id));
startActivity(i);
}
};
class Adapter extends CursorAdapter {
@SuppressWarnings("deprecation")
Adapter(Cursor c) {
super(ClientSites.this, c);
}
//@Override
public void bindView(View row, Context ctxt,
Cursor c) {
Holder holder=(Holder)row.getTag();
holder.populateFrom(c, dbHelper);
}
@Override
public View newView(Context ctxt, Cursor c,
ViewGroup parent) {
LayoutInflater inflater=getLayoutInflater();
View row = inflater.inflate(R.layout.row, parent, false);
Holder holder=new Holder(row);
row.setTag(holder);
return(row);
}
}
static class Holder {
private TextView name=null;
Holder(View row) {
name=(TextView)row.findViewById(R.id.ingredientText);
}
void populateFrom(Cursor c, DBUserAdapter r) {
name.setText(r.getName(c));
}
}
}
以下是我现在用来尝试在Listview中显示数据的代码。我从原来的尝试中改变了一些，但仍然不确定我做错了什么。
public void onCreate(Bundle savedInstanceState) {
try
{
super.onCreate(savedInstanceState);
//setContentView(R.layout.client_sites);
Intent i = getIntent();
String uID = String.valueOf(i.getIntExtra("userID", 0));
//int uID = i.getIntExtra("userID", 0);
//ListView myListView = (ListView)findViewById(R.id.myListView);
dbHelper = new DBUserAdapter(this);
dbHelper.createDatabase();
dbHelper.openDataBase();
String[] results = dbHelper.getSitesByClientname(uID);
//setListAdapter(new ArrayAdapter<String>(ClientSites.this, R.id.myListView, results));
//adapter = new ArrayAdapter<String>(ClientSites.this, R.id.myListView, results);
setListAdapter(new ArrayAdapter<String>(ClientSites.this, R.layout.client_sites, results));
//ListView myListView = (ListView)findViewById(R.id.myListView);
ListView listView = getListView();
listView.setTextFilterEnabled(true);
//ourCursor = dbHelper.getSitesByClientname(uID);
//Log.e("ALERT", uID.toString());
//startManagingCursor(ourCursor);
//Log.e("ERROR", "After start manage cursor: ");
//@SuppressWarnings("deprecation")
//SimpleCursorAdapter adapter = new SimpleCursorAdapter(getBaseContext(), R.id.myListView, null, null, null); // LOOK AT THIS IN THE MORNING!!!!!!!!!!!
//CursorAdapter adapter = new SimpleCursorAdapter(this, R.id.myListView, null, null, null, 0);
//adapter = new Adapter(ourCursor);
//Toast.makeText(ClientSites.this, "Booo!!!", Toast.LENGTH_LONG).show();
//myListView.setAdapter(adapter);
//myListView.setOnItemClickListener(onListClick);
答案 0 :(得分：2)
我从数据库创建了一个Listview。这是我用于我的应用程序的代码
这是数据库处理程序的一部分。它将返回我的列表视图的类别列表。如果这是你需要的，它可以返回一个字符串列表。
public List<Category> getAllCategorys() {
ArrayList<Category> categoryList = new ArrayList<Category>();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_CATEGORY;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
try{
if (cursor.moveToFirst()) {
do {
Category category = new Category();
category.setID(Integer.parseInt(cursor.getString(0)));
category.setCategory(cursor.getString(1));
// Adding category to list
categoryList.add(category);
} while (cursor.moveToNext());
}
}finally{
cursor.close();
}
db.close();
// return category list
return categoryList;
以下是我通过调用数据库填充ListView的方法。
int size = db.getCategoryCount();
List<Category> categoryList = db.getAllCategorys();
category_data = new String[size-1];
int i=0;
for(Category cn : categoryList)
{
category_data[i] = cn.getCategory(); // get the name of the category and add it to array
i++;
}
listAdapter = new ArrayAdapter<String>(this, R.layout.categoryrow, category_data);
listViw.setAdapter(listAdapter);
编辑：这是适合您的事情
public List<String> getSitesByClientname(String id) {
String[] args={id};
ArrayList<String> result = new ArrayList<String>();
SQLiteDatabase db = this.getWritableDatabase();
Cursor myCursor = db.rawQuery("SELECT client_sitename FROM " + CLIENT_SITES_TABLE + " WHERE client_id=?", args);
try{
if (myCursor.moveToFirst()){
do{
result.add(myCursor.getString(myCusor.getString(myCursor.getColumnIndex("client_sitename"));
}while(myCursor.moveToNext());
}
}finally{
myCursor.close();
}
db.close();
return result;
}
像这样使用
List<String> sites_data = dbHelper.getSitesByClientname(uID);
result_data = new String[sites_data.size()];
int i=0;
for(String s : sites_data)
{
result_data[i] = s; // get the name of the category and add it to array
i++;
}
listAdapter = new ArrayAdapter<String>(this, R.layout.client_sites, result_data);
listViw.setAdapter(listAdapter);
答案 1 :(得分：1)
如果你想从dbHelper返回Cursor，你可以这样做......
public Cursor getSitesByClientname(String id) {
String[] args={id};
return db.rawQuery("SELECT client_sitename FROM " + CLIENT_SITES_TABLE + " WHERE client_id=?", args);
}
我还需要一些时间来阅读listview tutorial