我正在使用Realm数据库从Mobile中的JSON保存数据。我正在使用自定义适配器而不是RealmAdapter。我能够保存数据并从Realm数据库中检索数据但是当我删除项目时按位置我收到一个错误，表示对象不再有效。
ToDoRealmAdapter
public class ToDoRealmAdapter extends RealmBaseAdapter<RealmDatabasePopularDestination> {
Context mContext;
RealmResults<RealmDatabasePopularDestination> clas_realm_bookmark = null;
String TAG = "HomeTab_adapter";
public ToDoRealmAdapter(@NonNull Context context, RealmResults<RealmDatabasePopularDestination> clas_realm_bookmark) {
super(context, clas_realm_bookmark);
this.context = mContext;
this.clas_realm_bookmark = clas_realm_bookmark;
}
@Override
public View getView(final int position, View convertView, ViewGroup parent) {
final Holder viewHolder;
if (convertView == null) {
// inflate the layout
LayoutInflater inflater = (LayoutInflater) mContext.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
// LayoutInflater inflater = LayoutInflater.from(parent.getContext());
convertView = inflater.inflate(R.layout.bookmark_grid_list_item, parent, false);
// well set up the ViewHolder
// viewHolder = new ClassScheduleStudentAdapter.Holder();
viewHolder = new Holder();
// viewHolder.popular_destintion_id = (TextView) convertView.findViewById(R.id.student_profile_subject);
viewHolder.title = (TextView) convertView.findViewById(R.id.festivalName);
viewHolder.imageLogo = (ImageView) convertView.findViewById(R.id.event_festival_main_image);
viewHolder.location = (TextView) convertView.findViewById(R.id.eventAddress);
viewHolder.monthEvent = (TextView) convertView.findViewById(R.id.textDateBookmark);
viewHolder.textViewIcon = (ImageView) convertView.findViewById(R.id.imageLocationBookmark);
// Log.d(TAG, "@@ postion:" + position + " getTeacherName" + class_destination.get(position).getId());
convertView.setTag(viewHolder);
} else {
// we've just avoided calling findViewById() on resource everytime
// just use the viewHolder
// viewHolder = (ClassScheduleStudentAdapter.Holder) convertView.getTag();
viewHolder = (Holder) convertView.getTag();
}
viewHolder.title.setText(clas_realm_bookmark.get(position).getTitle());
viewHolder.location.setText(clas_realm_bookmark.get(position).getLocation());
if (clas_realm_bookmark.get(position).getType().equals("popular_destination")) {
viewHolder.monthEvent.setVisibility(View.INVISIBLE);
viewHolder.textViewIcon.setImageResource(R.mipmap.fav_icon_popular);
} else {
viewHolder.monthEvent.setText(clas_realm_bookmark.get(position).getDateEvent());
viewHolder.textViewIcon.setImageResource(R.mipmap.events_festival_icon);
}
System.out.println("Display" + clas_realm_bookmark.get(position).getDateEvent());
Picasso picasso = Picasso.with(mContext);
// picasso.setIndicatorsEnabled(true);
picasso.load(clas_realm_bookmark.get(position).getImage()).memoryPolicy(MemoryPolicy.NO_STORE).networkPolicy(NetworkPolicy.OFFLINE).error(R.drawable.close).into(viewHolder.imageLogo, new Callback() {
@Override
public void onSuccess() {
}
@Override
public void onError() {
//Try again online if cache failed
Picasso.with(mContext)
.load(clas_realm_bookmark.get(position).getImage())
.error(R.drawable.close)
.into(viewHolder.imageLogo, new Callback() {
@Override
public void onSuccess() {
}
@Override
public void onError() {
Log.v("Picasso", "Could not fetch image");
}
});
}
});
//Picasso.with(mContext).load(clas_realm_bookmark.get(position).getImage()).error(R.drawable.close).into(viewHolder.imageLogo);
return convertView;
}
class Holder {
TextView title;
ImageView imageLogo;
TextView location;
TextView monthEvent;
ImageView textViewIcon;
}
}
PopularDestinationGridDetail
public void savetoDatabase() {
realm.executeTransactionAsync(new Realm.Transaction() {
@Override
public void execute(Realm bgRealm) {
//
count = (int) bgRealm.where(RealmDatabasePopularDestination.class).equalTo("Id", id).equalTo("Type", type).count();//mofidy Query here
if (count > 0) {
} else {
RealmDatabasePopularDestination realmDatabasePopularDestination = bgRealm.createObject(RealmDatabasePopularDestination.class);
realmDatabasePopularDestination.setId(id);
realmDatabasePopularDestination.setTitle(title);
realmDatabasePopularDestination.setLatitude(latitude);
realmDatabasePopularDestination.setLongitude(longitude);
realmDatabasePopularDestination.setImage(image);
realmDatabasePopularDestination.setType(type);
realmDatabasePopularDestination.setLocation(location);
realmDatabasePopularDestination.setDescription(description);
Log.v("Success", realmDatabasePopularDestination.getTitle());
}
}
}, new Realm.Transaction.OnSuccess() {
@Override
public void onSuccess() {
if (count > 0) {
Toast.makeText(PopularDestinationGridDetail.this, "Already added", LENGTH_LONG).show();
} else {
Toast.makeText(PopularDestinationGridDetail.this, "Added to Favorites", LENGTH_LONG).show();
}
Log.v("Success", title);
}
}, new Realm.Transaction.OnError() {
@Override
public void onError(Throwable error) {
Log.e("failed", error.getMessage());
}
});
}
收藏夹
public class Favourites extends Fragment {
Realm realm;
GridView gridViewBookmark;
RealmResults<RealmDatabasePopularDestination> destination_bookmark_realm =null;
RealmResults<RealmDatabasePopularDestination> realmDatabasePopularDestinations;
FavouriteAdapter favouriteAdapter;
ToDoRealmAdapter toDoRealmAdapter;
RealmChangeListener<RealmResults<RealmDatabasePopularDestination>> realmChangeListener = new RealmChangeListener<RealmResults<RealmDatabasePopularDestination>>() {
@Override
public void onChange(RealmResults<RealmDatabasePopularDestination> databasePopularDestinations) {
toDoRealmAdapter.notifyDataSetChanged();
}
};
@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
Realm.init(getContext());
realm = Realm.getDefaultInstance();
View view = inflater.inflate(R.layout.bookmark_layout_gridview, container, false);
gridViewBookmark = (GridView) view.findViewById(R.id.gridviewBookmark);
getData();
getGridItemClick();
return view;
}
RealmResults<RealmDatabasePopularDestination> result;
public void getData() {
result = realm.where(RealmDatabasePopularDestination.class).findAll();
result.load();
// System.out.println("Result" + result.get(0).getTitle());
for (int i = 0; i < result.size(); i++) {
//if(result.get(i).getType().equals("popular_destination")) {
destination_bookmark_realm.add(result.get(i));
//}else{
// destination_bookmark_realm.add(result.get(i));
//}
}
// favouriteAdapter = new FavouriteAdapter(getContext(), destination_bookmark_realm);
// gridViewBookmark.setAdapter(favouriteAdapter);
toDoRealmAdapter = new ToDoRealmAdapter(getContext(), destination_bookmark_realm);
gridViewBookmark.setAdapter(toDoRealmAdapter);
destination_bookmark_realm.addChangeListener((RealmChangeListener<RealmResults<RealmDatabasePopularDestination>>) realmChangeListener);
System.out.println("Result is" + result);
}
String type;
public void getType(final int pos) {
realm.executeTransactionAsync(new Realm.Transaction() {
@Override
public void execute(Realm bgRealm) {
//
RealmResults<RealmDatabasePopularDestination> results = bgRealm.where(RealmDatabasePopularDestination.class).findAll();//mofidy Query here
type = results.get(pos).getType();
System.out.println("LOg2" + type);
}
}, new Realm.Transaction.OnSuccess() {
@Override
public void onSuccess() {
}
}, new Realm.Transaction.OnError() {
@Override
public void onError(Throwable error) {
Log.e("failed", error.getMessage());
}
});
}
public void getGridItemClick() {
gridViewBookmark.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
getType(position);
System.out.println("LOg" + type);
if (type == null) {
return;
}
if (type.equals("popular_destination")) {
System.out.println("LOg4" + type);
Intent Bookmark_Popular_Des_grid_intent = new Intent(getContext(), PopularDestinationGridDetail.class);
Bundle popular_destination_bundle = new Bundle();
popular_destination_bundle.putString("Popular_Destination_ID", String.valueOf(destination_bookmark_realm.get(position).getId()));
popular_destination_bundle.putString("Fav_Flag", "1");
Bookmark_Popular_Des_grid_intent.putExtras(popular_destination_bundle);
startActivity(Bookmark_Popular_Des_grid_intent);
} else {
System.out.println("LOg5" + type);
Intent Bookmark_Event_fes_grid_intent = new Intent(getContext(), EventAndFestivalGridDetail.class);
Bundle event_festival_bundle = new Bundle();
event_festival_bundle.putString("Event_Festival_ID", String.valueOf(destination_bookmark_realm.get(position).getId()));
event_festival_bundle.putString("Fav_Flag", "2");
Bookmark_Event_fes_grid_intent.putExtras(event_festival_bundle);
startActivity(Bookmark_Event_fes_grid_intent);
}
}
});
}
@Override
public void onDestroy() {
super.onDestroy();
result.removeAllChangeListeners();
realm.close();
}
}
登录
e: FATAL EXCEPTION: main
Process: org.municipality.mobile.patanheritage, PID: 31896
java.lang.NoSuchFieldError: No field handlerController of type Lio/realm/HandlerController; in class Lio/realm/BaseRealm; or its superclasses (declaration of 'io.realm.BaseRealm' appears in /data/app/org.municipality.mobile.patanheritage-2/base.apk)
at io.realm.RealmBaseAdapter.addListener(RealmBaseAdapter.java:67)
at io.realm.RealmBaseAdapter.<init>(RealmBaseAdapter.java:60)
at org.municipality.mobile.patanheritage.adapter.ToDoRealmAdapter.<init>(ToDoRealmAdapter.java:36)
at org.municipality.mobile.patanheritage.activity.PopularDestinationGridDetail.onCreate(PopularDestinationGridDetail.java:121)
at android.app.Activity.performCreate(Activity.java:6662)
at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1118)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2599)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2707)
at android.app.ActivityThread.-wrap12(ActivityThread.java)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1460)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:154)
如何解决这个问题？
答案 0 :(得分：0)
如果删除任何线程上的给定RealmObject，那么当Realm更新（并调用RealmChangeListeners）时，该对象将不再有效，并且将不再可用于以前具有的任何public class FavouriteAdapter extends BaseAdapter {
Context mContext;
ArrayList<RealmDatabasePopularDestination> clas_realm_bookmark = null; // <-- BAD
String TAG = "HomeTab_adapter";
public FavouriteAdapter(Context mContext,
ArrayList<RealmDatabasePopularDestination> clas_realm_bookmark) { // <-- BAD
super();
this.mContext = mContext;
它
但是，无论出于何种原因，您都将RealmResults的内容复制到ArrayList
public class FavouriteAdapter extends BaseAdapter {
Context mContext;
List<RealmDatabasePopularDestination> clas_realm_bookmark = null;
String TAG = "HomeTab_adapter";
public FavouriteAdapter(Context mContext, List<RealmDatabasePopularDestination> clas_realm_bookmark) {
super();
this.mContext = mContext;
这是超级糟糕的，因为不仅结果集不再更新，而且它还能够存储和保留无效对象。
因此，
RealmResults<...> results;
FavouriteAdapter adapter;
RealmChangeListener<RealmResults<...>> realmChangeListener = (element) -> {
adapter.notifyDataSetChanged();
};
public void onCreate(Bundle b) {
....
results = realm.where(RealmDatabasePopularDestination.class).findAll();
FavouriteAdapter adapter = new FavouriteAdapter(this, results);
results.addChangeListener(realmChangeListener);
}
public void onDestroy() {
....
results.removeAllChangeListeners();
realm.close();
}
并且应该是
public class FavouriteAdapter extends RealmBaseAdapter<RealmDatabasePopularDestination> {
Context mContext;
//ArrayList<RealmDatabasePopularDestination> clas_realm_bookmark = null;
String TAG = "HomeTab_adapter";
public FavouriteAdapter(Context mContext, RealmResults<RealmDatabasePopularDestination> results) {
super(results);
...
与
...executeTransactionAsync(realm -> {
if (count > 0) {
// RealmResults<RealmDatabasePopularDestination> result = bgRealm.where(RealmDatabasePopularDestination.class).equalTo("Id", pop_dest_id).equalTo("Type", "popular_destination").findAll();
// result.deleteAllFromRealm();
// results = realm.where(RealmDatabasePopularDestination.class).equalTo("Id", pop_dest_id).equalTo("Type", "popular_destination").findAll();
// adapter = new FavouriteAdapter(getApplicationContext(), results);
// results.addChangeListener(realmChangeListener);
OR
array[i].onclick编辑：同样，完全删除评论代码
function setContentBox() {
for (var i = 0; i < jArrayText.length; i++)
document.getElementById(textWord[i]).onclick = function() {
var x = document.getElementById(textWord[i] + "commentB");
if (x.style.display === 'none') {
x.style.display = 'block';
} else {
x.style.display = 'none';
}
};
}
$(document).ready(function(){
setContentBox();
});