问题
i implemented Custom cursor adapter in my listview. but the listview is always null. Let me explain my codes:
OfflineAdapter offlineadapter = new OfflineAdapter(ctx, null);
listview.setAdapter(offlineadapter);
There's nothing really to explain Here. Moving into my offlineadapter Class:
public class OfflineAdapter extends CursorAdapter {
public com.androidarabia.lazylist.ImageLoader imageLoader;
@SuppressWarnings("deprecation")
public OfflineAdapter(Context context, Cursor c) {
super(context, c);
imageLoader = new com.androidarabia.lazylist.ImageLoader(
context.getApplicationContext());
Initializing...
public View newView(Context context, Cursor cursor, ViewGroup parent) {
LayoutInflater inflater = LayoutInflater.from(context);
View v = inflater.inflate(R.layout.pricelist, parent, false);
bindView(v, context, cursor);
return v;
}
Inflating layout...
@Override
public void bindView(View v, Context context, Cursor c) {
try {
String title = c.getString(c
.getColumnIndexOrThrow(LebanonSamsung.KEY_PHONENAME));
String date = c.getString(c
.getColumnIndexOrThrow(LebanonSamsung.KEY_MODELNUMBER));
String imagePath = c.getString(c
.getColumnIndexOrThrow(LebanonSamsung.KEY_PRICE));
String deletion = c.getString(c
.getColumnIndexOrThrow(LebanonSamsung.KEY_URL));
TextView title_text = (TextView) v.findViewById(R.id.title);
title_text.setText(title);
TextView date_text = (TextView) v.findViewById(R.id.modelnumber);
date_text.setText(date);
ImageView item_image = (ImageView) v.findViewById(R.id.list_image);
imageLoader.DisplayImage(deletion, item_image);
TextView del_image = (TextView) v.findViewById(R.id.details);
del_image.setText(imagePath);
} catch (Exception e) {
e.printStackTrace();
}
Yes, the database isn't null at all, i ran a check to view if it's null but it's not! What can i do? the listview is always empty. what i'm doing wrong??? Thanks!
**
UPDATE i noticed that im not closing cursor. Here's my database codes:
public class LebanonSamsung {
public static final String KEY_PHONENAME = "phone_name";
public static final String KEY_PRICE = "phone_price";
public static final String KEY_MODELNUMBER = "phone_modelnumber";
public static String prefName = "SecretFile";
static SharedPreferences prefs;
public static final String KEY_ROWID = "_id";
public static final String KEY_URL = "phone_picurl";
private static final String DATABASE_NAME = "PriceListDatabasesamsunglebanon";
private static final int DATABASE_VERSION = 1;
private static DbHelper ourHelper;
private static Context ourContext;
private static SQLiteDatabase mDb;
private static final String SQLITE_SAMSUNGLEBANON = "SamsungLebanon";
public static final String DATABASE_CREATESAMSUNGLEBANON = "CREATE TABLE IF NOT EXISTS "
+ SQLITE_SAMSUNGLEBANON
+ " ("
+ KEY_ROWID
+ " INTEGER PRIMARY KEY AUTOINCREMENT, "
+ KEY_PHONENAME
+ " TEXT NOT NULL, "
+ KEY_URL
+ " TEXT NOT NULL, "
+ KEY_PRICE
+ " TEXT NOT NULL, " + KEY_MODELNUMBER + " TEXT NOT NULL);";
private static class DbHelper extends SQLiteOpenHelper {
public DbHelper(Context ourContext) {
super(ourContext, DATABASE_NAME, null, DATABASE_VERSION);
prefs = ourContext.getSharedPreferences(prefName,
Context.MODE_PRIVATE);
}
@Override
public void onCreate(SQLiteDatabase arg0) {
// TODO Auto-generated method stub
arg0.execSQL(DATABASE_CREATESAMSUNGLEBANON);
}
@Override
public void onUpgrade(SQLiteDatabase arg0, int arg1, int arg2) {
// TODO Auto-generated method stub
arg0.execSQL("DROP TABLE IF EXISTS " + SQLITE_SAMSUNGLEBANON);
onCreate(arg0);
}
}
public LebanonSamsung(Context onNavigationListener) {
ourContext = onNavigationListener;
}
public LebanonSamsung open() throws SQLException {
ourHelper = new DbHelper(ourContext);
mDb = ourHelper.getWritableDatabase();
return this;
}
public void close() {
ourHelper.close();
}
public boolean deletesamsung() {
int doneDelete = 0;
doneDelete = mDb.delete(SQLITE_SAMSUNGLEBANON, null, null);
Log.w("error bi deleting l table", Integer.toString(doneDelete));
return doneDelete > 0;
}
public long createEntrySamsung(String phonename, String phoneprice,
String modelnumber, String url) {
ContentValues cv = new ContentValues();
cv.put(KEY_PHONENAME, phonename);
cv.put(KEY_PRICE, phoneprice);
cv.put(KEY_MODELNUMBER, modelnumber);
cv.put(KEY_URL, url);
return mDb.insert(SQLITE_SAMSUNGLEBANON, null, cv);
}
public Cursor listsamsung() {
Cursor mCursor = mDb.query(SQLITE_SAMSUNGLEBANON,
new String[] { KEY_ROWID, KEY_PHONENAME, KEY_PRICE,
KEY_MODELNUMBER, KEY_URL }, null, null, null, null,
null);
if (mCursor != null) {
mCursor.moveToFirst();
}
return mCursor;
}
public void insertsamsung() {
// TODO Auto-generated method stub
new insertentries().execute("");
}
public class insertentries extends AsyncTask<String, Integer, String> {
protected void onPreExecute() {
}
@Override
protected String doInBackground(String... params) {
// TODO Auto-generated method stub
InputStream isr = null;
String result = "";
try {
String url;
HttpClient httpclient = new DefaultHttpClient();
String range = prefs.getString("range", "1");
String sortby = prefs.getString("filtering", "ByDate");
url = "there's a url";
Log.e("url", url);
HttpPost httpost = new HttpPost(url);
HttpResponse resposne = httpclient.execute(httpost);
HttpEntity entity = resposne.getEntity();
isr = entity.getContent();
BufferedReader reader = new BufferedReader(
new InputStreamReader(isr, "UTF-8"), 8);
StringBuilder sb = new StringBuilder();
String line = null;
while ((line = reader.readLine()) != null) {
sb.append(line + "\n");
}
isr.close();
result = sb.toString();
JSONArray jArray = new JSONArray(result);
for (int i = 0; i < jArray.length(); i++) {
JSONObject json = jArray.getJSONObject(i);
createEntrySamsung(json.getString("PhoneName"),
json.getString("PhonePrice"),
json.getString("ModelNumber"),
json.getString("imageurl"));
}
} catch (Exception e) {
Log.e("log_tag", "Error converting Result " + e.toString());
}
return result;
}
protected void onProgressUpdate(Integer... progress) {
}
protected void onPostExecute(String result) {
}
}
}Anybody
? LOGCAT:
08-06 17:13:10.753: E/SQLiteDatabase(532): close() was never explicitly called on database '/data/data/com.androidarabia.phones/databases/PriceListDatabasesamsunglebanon'
08-06 17:13:10.753: E/SQLiteDatabase(532): android.database.sqlite.DatabaseObjectNotClosedException: Application did not close the cursor or database object that was opened here
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.database.sqlite.SQLiteDatabase.<init>(SQLiteDatabase.java:1943)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:1007)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.database.sqlite.SQLiteDatabase.openDatabase(SQLiteDatabase.java:986)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.database.sqlite.SQLiteDatabase.openOrCreateDatabase(SQLiteDatabase.java:1051)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.app.ContextImpl.openOrCreateDatabase(ContextImpl.java:770)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.content.ContextWrapper.openOrCreateDatabase(ContextWrapper.java:221)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.database.sqlite.SQLiteOpenHelper.getWritableDatabase(SQLiteOpenHelper.java:157)
08-06 17:13:10.753: E/SQLiteDatabase(532): at com.androidarabia.databases.LebanonSamsung.open(LebanonSamsung.java:81)
08-06 17:13:10.753: E/SQLiteDatabase(532): at com.androidarabia.drawer.SamsungLB.onCreateView(SamsungLB.java:65)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.support.v4.app.Fragment.performCreateView(Fragment.java:1478)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:927)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1104)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1460)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:472)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.support.v4.app.FragmentPagerAdapter.finishUpdate(FragmentPagerAdapter.java:141)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.support.v4.view.ViewPager.populate(ViewPager.java:1068)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.support.v4.view.ViewPager.populate(ViewPager.java:914)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.support.v4.view.ViewPager.onMeasure(ViewPager.java:1436)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.view.View.measure(View.java:12723)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:594)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:376)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.view.View.measure(View.java:12723)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4698)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.view.View.measure(View.java:12723)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4698)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.view.View.measure(View.java:12723)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4698)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.view.View.measure(View.java:12723)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.widget.LinearLayout.measureVertical(LinearLayout.java:812)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.widget.LinearLayout.onMeasure(LinearLayout.java:553)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.view.View.measure(View.java:12723)
08-06 17:13:10.753: E/SQLiteDatabase(532): at com.jeremyfeinstein.slidingmenu.lib.CustomViewAbove.onMeasure(CustomViewAbove.java:456)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.view.View.measure(View.java:12723)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.widget.RelativeLayout.measureChildHorizontal(RelativeLayout.java:594)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.widget.RelativeLayout.onMeasure(RelativeLayout.java:376)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.view.View.measure(View.java:12723)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.view.ViewGroup.measureChildWithMargins(ViewGroup.java:4698)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.widget.FrameLayout.onMeasure(FrameLayout.java:293)
08-06 17:13:10.753: E/SQLiteDatabase(532): at com.android.internal.policy.impl.PhoneWindow$DecorView.onMeasure(PhoneWindow.java:2092)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.view.View.measure(View.java:12723)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.view.ViewRootImpl.performTraversals(ViewRootImpl.java:1064)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.view.ViewRootImpl.handleMessage(ViewRootImpl.java:2442)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.os.Handler.dispatchMessage(Handler.java:99)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.os.Looper.loop(Looper.java:137)
08-06 17:13:10.753: E/SQLiteDatabase(532): at android.app.ActivityThread.main(ActivityThread.java:4424)
08-06 17:13:10.753: E/SQLiteDatabase(532): at java.lang.reflect.Method.invokeNative(Native Method)
08-06 17:13:10.753: E/SQLiteDatabase(532): at java.lang.reflect.Method.invoke(Method.java:511)
08-06 17:13:10.753: E/SQLiteDatabase(532): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:784)
08-06 17:13:10.753: E/SQLiteDatabase(532): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:551)
08-06 17:13:10.753: E/SQLiteDatabase(532): at dalvik.system.NativeStart.main(Native Method)
08-06 17:13:10.793: E/System(532): Uncaught exception thrown by finalizer
08-06 17:13:10.875: E/System(532): java.lang.IllegalStateException: Don't have database lock!
08-06 17:13:10.875: E/System(532): at android.database.sqlite.SQLiteDatabase.verifyLockOwner(SQLiteDatabase.java:2090)
08-06 17:13:10.875: E/System(532): at android.database.sqlite.SQLiteDatabase$1.entryRemoved(SQLiteDatabase.java:2182)
08-06 17:13:10.875: E/System(532): at android.database.sqlite.SQLiteDatabase$1.entryRemoved(SQLiteDatabase.java:2178)
08-06 17:13:10.875: E/System(532): at android.util.LruCache.trimToSize(LruCache.java:197)
08-06 17:13:10.875: E/System(532): at android.util.LruCache.evictAll(LruCache.java:285)
08-06 17:13:10.875: E/System(532): at android.database.sqlite.SQLiteDatabase.deallocCachedSqlStatements(SQLiteDatabase.java:2143)
08-06 17:13:10.875: E/System(532): at android.database.sqlite.SQLiteDatabase.closeClosable(SQLiteDatabase.java:1126)
08-06 17:13:10.875: E/System(532): at android.database.sqlite.SQLiteDatabase.finalize(SQLiteDatabase.java:1914)
08-06 17:13:10.875: E/System(532): at java.lang.Daemons$FinalizerDaemon.doFinalize(Daemons.java:182)
08-06 17:13:10.875: E/System(532): at java.lang.Daemons$FinalizerDaemon.run(Daemons.java:168)
08-06 17:13:10.875: E/System(532): at java.lang.Thread.run(Thread.java:856)
回答1:
This line the second value should be a Cursor retrived from your DB
OfflineAdapter offlineadapter = new OfflineAdapter(ctx, null);
Try:
LebanonSamsung lSamsung= new LebanonSamsung(ctx).open();
Cursor c = lSamsung.listsamsung();
OfflineAdapter offlineadapter = new OfflineAdapter(ctx, c);
Another issue you might have is that you are populating your DB with a background task, where are you calling "insertsamsung()"? , you should consider setting the adapter to your list in the onPostExecute function.
来源：https://stackoverflow.com/questions/18034372/filling-listview-using-cursoradapter