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can butterknife bind OnTextChanged events to multiple controls like this?

我想对多个EditText设置监听事件，但看起来好像一次只能绑定一个资源，我知道OnClick方法可以绑定多个资源id，但EditText 好像不行，我不确定想问一下各位，英文不好请见谅
I'd like to set up listening events for multiple EditTexts, but it looks like I can only bind one resource at a time. I know the OnClick method can bind multiple resource ids, but EditText doesn't seem to work. I'm not sure I want to ask you, but I'm sorry for the English.
#OnTextChanged(**R.id.et_account ,R.id.et_password** , callback = OnTextChanged.Callback.AFTER_TEXT_CHANGED)
void afterTextChanged(Editable s) {
if (TextUtils.isEmpty(etPassword.getText().toString())) {
ivCleanPassword.setVisibility(View.GONE);
iv_eye.setVisibility(View.GONE);
} else {
ivCleanPassword.setVisibility(View.VISIBLE);
iv_eye.setVisibility(View.VISIBLE);
}
if (TextUtils.isEmpty(etAccount.getText().toString())) {
ivCleanAccount.setVisibility(View.GONE);
} else {
ivCleanAccount.setVisibility(View.VISIBLE);
}
}

Technically it’s possible:
#OnTextChanged({R.id.edittext1, R.id.edittext2})
but it’s a bit problematic because it’s hard to determine which view triggered the call.
For discussion on this topic see https://github.com/JakeWharton/butterknife/issues/672

Google Fit Listen for Data Updates not working

I'm trying to implement a Google Fit Listener when data is updated into Google Fit services.
In this link of Google Fit documentation there is a simple example, however, it is not 100% clear. For that reason, I have two problems:
I don't know how to implement mResultCallback variable (there aren't any examples in this documentation).
When I define a simple ResultCallback (it seems to work but I'm not sure) and I launch the application, it gives me a result error code: java.lang.SecurityException: Signature check failed

The code within the HistortyApi lists one of android.permission.ACCESS_FINE_LOCATION or android.permission.BODY_SENSORS as being required.
Adding those permissions to my code hasn't resolved the same problem though.
Confirmed bug in Google Fit services. See discussion in https://plus.google.com/110141422948118561903/posts/Lqri4LVR7cD

mResultCallback is a ResultCallback<Status> so you need to implement a class of that type. Documentation is here, but there's only one method you need to implement:
public abstract void onResult (Status result)
The standard way is to do this using an anonymous class either when you declare mResultCallback or when you're using it as a parameter. Below is an example from Google's BasicRecordingAPI example:
Fitness.RecordingApi.subscribe(mClient, DataType.TYPE_ACTIVITY_SAMPLE)
.setResultCallback(new ResultCallback<Status>() {
#Override
public void onResult(Status status) {
if (status.isSuccess()) {
if (status.getStatusCode()
== FitnessStatusCodes.SUCCESS_ALREADY_SUBSCRIBED) {
Log.i(TAG, "Existing subscription for activity detected.");
} else {
Log.i(TAG, "Successfully subscribed!");
}
} else {
Log.i(TAG, "There was a problem subscribing.");
}
}
});
If you want to use a member variable you can simply make an assignment instead:
ResultCallback<Status> mResultCallback = new ResultCallback<Status>() {
#Override
public void onResult(Status status) {
...
}
});
Of course you can define a non-anonymous class, but if you did that for every callback you had you would end up creating a LOT of classes.

How do I show a notification in IntelliJ?

Figured out how to show one of those little notification bubble messages in the top right of the screen, answer below.

Turns out, you have to make a NotificationGroup instance, and then use that to make a Notification, and pass the notification and the Project to Notifications.Bus.notify().
public class VoiceApplicationComponentImpl implements ApplicationComponent, VoiceApplicationComponent {
...
public static final NotificationGroup GROUP_DISPLAY_ID_INFO =
new NotificationGroup("My notification group",
NotificationDisplayType.BALLOON, true);
...
void showMyMessage(String message) {
ApplicationManager.getApplication().invokeLater(new Runnable() {
#Override
public void run() {
Notification notification = GROUP_DISPLAY_ID_INFO.createNotification(message, NotificationType.ERROR);
Project[] projects = ProjectManager.getInstance().getOpenProjects();
Notifications.Bus.notify(notification, projects[0]);
}
});
}
Note: you'll probably have a better way to get the current Project, right now I just assume there's one open project. This means my method doesn't work on startup (projects array is empty).
Another note: you'll probably not need to wrap with the invokeLater but I did, because I was calling showMyMessage in a different thread.

this will be better!
StatusBar statusBar = WindowManager.getInstance()
.getStatusBar(DataKeys.PROJECT.getData(actionEvent.getDataContext()));
JBPopupFactory.getInstance()
.createHtmlTextBalloonBuilder(htmlText, messageType, null)
.setFadeoutTime(7500)
.createBalloon()
.show(RelativePoint.getCenterOf(statusBar.getComponent()),
Balloon.Position.atRight);
reference link：
1. original link
2. enter link description here

Android: Fragments, SQLite and Loaders

So I've come to a point where I need to implement an SQLite database for my app.
Following "The Busy Coder's guide to Android Development" I have created a DatabaseHelper class that extends SQLiteOpenHelper.
One of my use cases is to run a query against the database and display the results on a ListView within a Fragment (I use fragments from the support library).
From what I understand, using managedQuery() is not really appropriate and even if it were it isn't recommended due to the fact that some of the logic encapsulated inside this method is actually executed on the main thread, specifically reQuery() which to my understanding is performed when the Activity is restarted.
So I've been trying to get acquainted with the Loader class for the first time, only to see this:
"The only supplied concrete implementation of a Loader is CursorLoader, and that is only for use with a ContentProvider"
My initial thought was to implement my own content provider and perhaps prevent other apps from getting access to it, then I read the following in the ContentProvider documentation via developer.android.com:
"You don't need a provider to use an SQLite database if the use is entirely within your own application."
I've also been playing with this:
https://github.com/commonsguy/cwac-loaderex
Yet I am not familiar with this project, and not sure if it can be used on a production environment.
So, right now all I can think of is creating a bunch of AsyncTask instances within my Fragment and manage their lifecycle appropriately, make sure they're cancelled whenever needed and whatnot.
Are there any other options?

I think implementing content provider is a good idea, no matter that data will not be accessible outside of the application. It provides very modern interface and from my experience makes your application error prone to database locking issues and other db-specific problems.
I've implemented it in my latest project and I was very happy to use it.

You can extend Loader class in order to perform other Async work such as loading directly from your DB.
Here is an example of that
Edit: added A better example of Loader usage.
Finally managed to find the tutorial that really helped me understand how things work.
By extending the loader class you can avoid messing with content observers and its quite easy to implement (at last)
the modifications that need to be taken in your code are
Add implementation of LoaderManager.LoaderCallbacks<D>, where D is your data list (snippet 1)
Create your loader class, copy snippet 2, and add the loading of your data from the DB
Finally call the loaders 1 call for init and then for refreshing the restart call. (snippet 2 & 3)
Snippet 1: How to "link" the loader with your fragment:
public static class AppListFragment extends ListFragment implements
LoaderManager.LoaderCallbacks<List<SampleItem>> {
public Loader<List<SampleItem>> onCreateLoader(int id, Bundle args) {
//...
return new SampleLoader (getActivity());
}
public void onLoadFinished(Loader<List<SampleItem>> loader, List<SampleItem> data) {
// ...
mAdapter.setData(data);
if (isResumed()) {
setListShown(true);
} else {
setListShownNoAnimation(true);
}
// ...
}
public void onLoaderReset(Loader<List<SampleItem>> loader) {
// ...
mAdapter.setData(null);
// ...
}
/* ... */
}
Snippet 2: Schema of your custom loader: (I have double commented the observer things as I believe that it is quite difficult to implement it from the beginning and you can simple recall the loader without messing with that automated refreshing)
public class SampleLoader extends AsyncTaskLoader<List<SampleItem>> {
// We hold a reference to the Loader’s data here.
private List<SampleItem> mData;
public SampleLoader(Context ctx) {
// Loaders may be used across multiple Activitys (assuming they aren't
// bound to the LoaderManager), so NEVER hold a reference to the context
// directly. Doing so will cause you to leak an entire Activity's context.
// The superclass constructor will store a reference to the Application
// Context instead, and can be retrieved with a call to getContext().
super(ctx);
}
/****************************************************/
/** (1) A task that performs the asynchronous load **/
/****************************************************/
#Override
public List<SampleItem> loadInBackground() {
// This method is called on a background thread and should generate a
// new set of data to be delivered back to the client.
List<SampleItem> data = new ArrayList<SampleItem>();
// TODO: Perform the query here and add the results to 'data'.
return data;
}
/********************************************************/
/** (2) Deliver the results to the registered listener **/
/********************************************************/
#Override
public void deliverResult(List<SampleItem> data) {
if (isReset()) {
// The Loader has been reset; ignore the result and invalidate the data.
releaseResources(data);
return;
}
// Hold a reference to the old data so it doesn't get garbage collected.
// We must protect it until the new data has been delivered.
List<SampleItem> oldData = mData;
mData = data;
if (isStarted()) {
// If the Loader is in a started state, deliver the results to the
// client. The superclass method does this for us.
super.deliverResult(data);
}
// Invalidate the old data as we don't need it any more.
if (oldData != null && oldData != data) {
releaseResources(oldData);
}
}
/*********************************************************/
/** (3) Implement the Loader’s state-dependent behavior **/
/*********************************************************/
#Override
protected void onStartLoading() {
if (mData != null) {
// Deliver any previously loaded data immediately.
deliverResult(mData);
}
// Begin monitoring the underlying data source.
////if (mObserver == null) {
////mObserver = new SampleObserver();
// TODO: register the observer
////}
//// takeContentChanged() can still be implemented if you want
//// to mix your refreshing in that mechanism
if (takeContentChanged() || mData == null) {
// When the observer detects a change, it should call onContentChanged()
// on the Loader, which will cause the next call to takeContentChanged()
// to return true. If this is ever the case (or if the current data is
// null), we force a new load.
forceLoad();
}
}
#Override
protected void onStopLoading() {
// The Loader is in a stopped state, so we should attempt to cancel the
// current load (if there is one).
cancelLoad();
// Note that we leave the observer as is. Loaders in a stopped state
// should still monitor the data source for changes so that the Loader
// will know to force a new load if it is ever started again.
}
#Override
protected void onReset() {
// Ensure the loader has been stopped.
onStopLoading();
// At this point we can release the resources associated with 'mData'.
if (mData != null) {
releaseResources(mData);
mData = null;
}
// The Loader is being reset, so we should stop monitoring for changes.
////if (mObserver != null) {
// TODO: unregister the observer
//// mObserver = null;
////}
}
#Override
public void onCanceled(List<SampleItem> data) {
// Attempt to cancel the current asynchronous load.
super.onCanceled(data);
// The load has been canceled, so we should release the resources
// associated with 'data'.
releaseResources(data);
}
private void releaseResources(List<SampleItem> data) {
// For a simple List, there is nothing to do. For something like a Cursor, we
// would close it in this method. All resources associated with the Loader
// should be released here.
}
/*********************************************************************/
/** (4) Observer which receives notifications when the data changes **/
/*********************************************************************/
// NOTE: Implementing an observer is outside the scope of this post (this example
// uses a made-up "SampleObserver" to illustrate when/where the observer should
// be initialized).
// The observer could be anything so long as it is able to detect content changes
// and report them to the loader with a call to onContentChanged(). For example,
// if you were writing a Loader which loads a list of all installed applications
// on the device, the observer could be a BroadcastReceiver that listens for the
// ACTION_PACKAGE_ADDED intent, and calls onContentChanged() on the particular
// Loader whenever the receiver detects that a new application has been installed.
// Please don’t hesitate to leave a comment if you still find this confusing! :)
////private SampleObserver mObserver;
}
Snippet 3: How to call the loader for the first time (ONLY)
// Initialize a Loader with an id. If the Loader with this id is not
// initialized before
getLoaderManager().initLoader(LOADER_ID, null, this);
Snippet 4: For refreshing data (recalling the query)
// Check if the loader exists and then restart it.
if (getLoaderManager().getLoader(LOADER_ID) != null)
getLoaderManager().restartLoader(LOADER_ID, null, this);
Reference:
Snippet 1 : usage of loader extracted from here
Snippet 2 : here for more info and logic read throughout the hole article
Snippet 3 & 4: are just loader usage.
Full code of these is also uploaded by the creator on github

I recommend OrmLite library, a lightweight Object Relational Mapping that can work for Android. This library will make your life easier . You don't need to create or update database by hand, you don't need to focus on managing database connection, all queries select, insert, update will be easier with a DAO approach (usually you don't need to write your own sql query) and a lot of features. They have some examples that you can start with.
And if you want to use the Loader, there is a ORMLite Extras , additional functionality for ORMLite available on github (You can use the support package which is compatible with support android library). Here is an example usage on my previous project:
public class EventsFragment extends Fragment implements LoaderCallbacks<Cursor>{
private static final int LOADER_ID = EventsFragment.class.getName().hashCode();
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
getLoaderManager().initLoader(LOADER_ID, null, this);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View layoutRoot = inflater.inflate(
R.layout.fragment_events, null);
lvEvents = (ListView) layoutRoot.findViewById(R.id.lvEvents);
adapter = new EventAdapter(getActivity(), null, null);
lvEvents.setAdapter(adapter);
return layoutRoot;
}
#Override
public Loader<Cursor> onCreateLoader(int arg0, Bundle arg1) {
try {
PreparedQuery<Event> query = getDatabaseHelper().getEventDao().getQuery();
return getDatabaseHelper().getEventDao().getSQLCursorLoader(query );
} catch (Exception e) {
e.printStackTrace();
}
return null;
}
#Override
public void onLoadFinished(Loader<Cursor> arg0, Cursor cursor) {
adapter.swapCursor(cursor);
try {
adapter.setQuery(getDatabaseHelper().getEventDao().getQuery());
} catch (SQLException e) {
e.printStackTrace();
}
}
#Override
public void onLoaderReset(Loader<Cursor> arg0) {
adapter.swapCursor(null);
}
private OrmliteDatabaseHelper getDatabaseHelper(){
return ((MainActivity)getActivity()).getDatabaseHelper();
}
}
The adapter
public class EventAdapter extends OrmliteCursorAdapter<Event>{
public EventAdapter(Context context, Cursor c, PreparedQuery<Event> query) {
super(context, c, query);
}
#Override
public void bindView(View itemView, Context context, Event item) {
TextView tvEventTitle = (TextView) itemView.findViewById(R.id.tvEventTitle);
TextView tvEventStartDate = (TextView) itemView.findViewById(R.id.tvEventStartDate);
tvEventTitle.setText(item.getTitle());
tvEventStartDate.setText(item.getFormatStartDate());
}
#Override
public View newView(Context context, Cursor arg1, ViewGroup arg2) {
LayoutInflater inflater = LayoutInflater.from(context);
View retView = inflater.inflate(R.layout.event_item_row, arg2, false);
return retView;
}
}
And a custom Dao which provides PreparedQuery for cursor adapter above:
public interface IEventDao extends Dao<Event, Integer>{
PreparedQuery<Event> getQuery() throws SQLException;
OrmliteCursorLoader<Event> getSQLCursorLoader(Context context, PreparedQuery<Event> query) throws SQLException;
}
public class EventDao extends AndroidBaseDaoImpl<Event, Integer> implements IEventDao{
public EventDao(ConnectionSource connectionSource) throws SQLException {
super(connectionSource, Event.class);
}
public EventDao(ConnectionSource connectionSource,
DatabaseTableConfig<Event> tableConfig) throws SQLException {
super(connectionSource, tableConfig);
}
#Override
public PreparedQuery<Event> getQuery() throws SQLException{
return queryBuilder().prepare();
}
}
Hope this can help!

If your database contains thousands of records consider madlymad's answer
If not keep it stupid and simple, use SQLiteOpenHelper and create a method that returns you your data as array of strings or define your one objects.
Also use custom/regular CursorAdapter or ArrayAdapter.

I use the SQLiteOpenHelper to create my database. I have made Java classes for all the tables and when I get the data from my database I put it in an ArrayList. The ArrayList I then load into the adapter of the Listview.

Loader doesn't start after calling initLoader()?

I have a fragment, and want to start a loader when a button is clicked:
public class MyFragment extends Fragment {
public void onActivityCreated() {
super.onActivityCreated();
Button btn = ...;
btn.setOnClickListener(new OnClickListener() {
public void onClick(View view) {
getLoaderManager().initLoader(500, null, mMyCallback);
}
});
}
private LoaderManager.LoaderCallbacks<String> mMyCallback = new LoaderManager.LoaderCallbacks<String>() {
#Override
public Loader<String> onCreateLoader(int arg0, Bundle arg1) {
Log.e(TAG, "LoaderCallback.onCreateLoader().");
return new MyLoader(getActivity());
}
}
}
public class MyLoader extends AsyncTaskLoader<String> {
public MyLoader(Context context) {
super(context);
}
#Override
public String loadInBackground() {
Log.e(TAG, "Hi, running.");
return "terrific.";
}
}
After clicking the button, I can see my callback's onCreateLoader method called, but the created loader never actually starts. Do we need to call forceLoad() on the loader itself to get it to actually start? None of the sample posts do this,
Thanks

You need to implement onStartLoading() and call forceLoad() somewhere in the method.
See this post for more information: Implementing Loaders (part 3)

In my experience it never worked unless I used forceLoad().
You may find the answer to this previous question helpful:
Loaders in Android Honeycomb

Three important points regarding Loaders are:
Always Use forceLoad() method while initialising Loaders. For Example:
getLoaderManager().initLoader(500, null, mMyCallback).forceLoad();
Always implement onStartLoading(). This function will automatically be called by LoaderManager when the associated fragment/activity is being started.
Make sure the ID of the loader is unique otherwise new Loader will not be called.
If there is still a problem you can check the state of loader by calling the isStarted() method.

You need to keep a reference to the instance of the loader you create in the method onCreateLoader. Then, to refresh it, call yourLoader.onContentChanged();

If you have more than 1 loader in the same activity, make sure their id differs. I lost few hours to figure it out :)