At first I have code like this
private void example(){
btnBack.setOnClickListener(new View.OnClickListener() {
#Override public void onClick(View view) {
//some code
}
});
}
and then get code like this
private void example(){
btnBack.setOnClickListener(backListener);
}
View.OnClickListener backListener = new View.OnClickListener() {
#Override public void onClick(View view) {
//some code
}
};
That is simply "Extract -> Field" (Ctrl-Alt-F in Windows/Linux keymaps)
Related
I am very new to Android programming. I can't find a solution for my current problem which I've been trying to solve for days.
I want to click on item of populated Array List and get the position i.e. the searched word result in Cardview (neither ItemClickListener nor OnSuggestionListener did work here. Here is my code of MainActivity and I would be very thankful if somebody could help me out:
RecyclerView recyclerView;
RecyclerView.LayoutManager layoutManager;
SearchAdapter adapter;
MaterialSearchBar materialSearchBar;
List<String> suggestList = new ArrayList<>();
Database database;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//init View
recyclerView = (RecyclerView) findViewById(R.id.recycler_search);
layoutManager = new LinearLayoutManager(this);
recyclerView.setLayoutManager(layoutManager);
recyclerView.setHasFixedSize(true);
materialSearchBar = (MaterialSearchBar) findViewById(R.id.search_bar);
database = new Database(this);
materialSearchBar.setHint("Search");
materialSearchBar.setCardViewElevation(10);
loadSuggestList();
materialSearchBar.addTextChangeListener (new TextWatcher() {
#Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {
}
#Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
List<String> suggest = new ArrayList<>();
for (String search : suggestList) {
if (search.toLowerCase().contains(materialSearchBar.getText().toLowerCase()))
suggest.add(search);
}
materialSearchBar.setLastSuggestions(suggest);
}
#Override
public void afterTextChanged(Editable s) {
}
});
materialSearchBar.setOnSearchActionListener (new MaterialSearchBar.OnSearchActionListener() {
#Override
public void onSearchStateChanged(boolean enabled) {
if (!enabled)
adapter = new SearchAdapter(getBaseContext(), database.getLughats());
recyclerView.setAdapter(adapter);
}
#Override
public void onSearchConfirmed(CharSequence text) {
startSearch(text.toString());
}
#Override
public void onButtonClicked(int buttonCode) {
}
});
adapter = new SearchAdapter(this, database.getLughats());
recyclerView.setAdapter(adapter);
}
private void startSearch(String text) {
adapter = new SearchAdapter(this, database.getLughatByWort(text));
recyclerView.setAdapter(adapter);
}
private void loadSuggestList() {
suggestList = database.getWorts();
materialSearchBar.setLastSuggestions(suggestList);
}
}```
Let me know if I should post here also my AdapterCode for the ViewHolder.
Thank you for your help in advance!
Here ist my AdapterCode:
class SearchViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener{
RecyclerItemClick itemClickListener;
public TextView wort, praeteritum, partizip2, artikelGrammatik, uebersetzung1, uebersetzung2;
public ImageButton button1, button2;
public SearchViewHolder(#NonNull View itemView) {
super(itemView);
wort = (TextView)itemView.findViewById(R.id.wort);
praeteritum = (TextView)itemView.findViewById(R.id.praeteritum);
partizip2 = (TextView)itemView.findViewById(R.id.partizip2);
artikelGrammatik = (TextView)itemView.findViewById(R.id.artikelGrammatik);
uebersetzung1 = (TextView)itemView.findViewById(R.id.uebersetzung1);
uebersetzung2 = (TextView)itemView.findViewById(R.id.uebersetzung2);
button1 = (ImageButton)itemView.findViewById(R.id.button_id_1);
button2 = (ImageButton) itemView.findViewById(R.id.button_id_2);
itemView.setOnClickListener(this);
}
#Override
public void onClick(View v) {
this.itemClickListener.onItemClickListener(v, getLayoutPosition());
}
public void setItemClickListener(RecyclerItemClick ic) {
this.itemClickListener = ic;
}
}
public class SearchAdapter extends RecyclerView.Adapter<SearchViewHolder> {
private Context context;
private List<Lughat> lughats;
public SearchAdapter(Context context, List<Lughat> lughats) {
this.context = context;
this.lughats = lughats;
}
#NonNull
#Override
public SearchViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(parent.getContext());
final View itemView = inflater.inflate(R.layout.layout_item, parent, false);
return new SearchViewHolder(itemView);
}
#Override
public void onBindViewHolder(#NonNull final SearchViewHolder holder, final int position) {
holder.wort.setText(lughats.get(position).getWort());
holder.praeteritum.setText(lughats.get(position).getPraeteritum());
holder.partizip2.setText(lughats.get(position).getPartizip2());
holder.artikelGrammatik.setText(lughats.get(position).getArtikelGrammatik());
holder.uebersetzung1.setText(lughats.get(position).getUebersetzung1());
holder.uebersetzung2.setText(lughats.get(position).getUebersetzung2());
CharSequence praet;
praet = holder.praeteritum.getText();
if (praet.length() == 0) {
holder.praeteritum.setVisibility(View.GONE);
holder.button1.setVisibility(View.GONE);
} else {
holder.praeteritum.setVisibility(View.VISIBLE);
holder.button1.setVisibility(View.VISIBLE);
}
CharSequence part2;
part2 = holder.partizip2.getText();
if (part2.length() == 0) {
holder.partizip2.setVisibility(View.GONE);
} else {
holder.partizip2.setVisibility(View.VISIBLE);
}
CharSequence artGr;
artGr = holder.artikelGrammatik.getText();
if (artGr.length() == 0) {
holder.artikelGrammatik.setVisibility(View.GONE);
holder.button2.setVisibility(View.GONE);
} else {
holder.artikelGrammatik.setVisibility(View.VISIBLE);
holder.button2.setVisibility(View.VISIBLE);
}
CharSequence ueb2;
ueb2 = holder.uebersetzung2.getText();
if (ueb2.length() == 0) {
holder.uebersetzung2.setVisibility(View.GONE);
} else {
holder.uebersetzung2.setVisibility(View.VISIBLE);
}
holder.button1.setOnClickListener(new ToastMaker(context.getApplicationContext()));
holder.button2.setOnClickListener(new ToastMaker(context.getApplicationContext()));
holder.setItemClickListener(new RecyclerItemClick() {
#Override
public void onItemClickListener(View v, int position) {
Toast.makeText(context, "Begriff", Toast.LENGTH_LONG).show();
}
});
}
#Override
public int getItemCount() {
return lughats.size();
}
}
If I do it also with OnClickListener it does not work too, it does not call the method startSearch.
button3.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
CharSequence text = materialSearchBar.getText();
Toast.makeText(getApplicationContext(), text, Toast.LENGTH_LONG).show();
startSearch(text.toString());
}
my android application keeps lagging on back navigation after i implemented the network calls.For network calls I'm using rxandroid/retrofit. I've tried to fix it using both single & observable. Both makes the app lagging the same way.This is my code while using observable. Lagging occurs while loading data to recyclerviews. So I have added the adapter class also.
#Override
public void onResume() {
super.onResume();
getMenuByShopAndCategoryId(categoryRequest.getId(), Utility.getShop(getActivity()));
}
private void getMenuByShopAndCategoryId(int categoryId, int shopId){
Repository.getInstance()
.getMenuByShopAndCategoryId(categoryId,shopId)
.subscribeOn(Schedulers.io())
.observeOn(AndroidSchedulers.mainThread())
.subscribe(new Observer<Response<MenuResponse>>() {
#Override
public void onSubscribe(Disposable d) {
disposable.add(d);
}
#Override
public void onNext(Response<MenuResponse> menuResponse) {
//other calculations
}
}
#Override
public void onError(Throwable e) {
//error handling
}
#Override
public void onComplete() {
}
});
}
#Override
public void onDestroy() {
disposable.dispose();
super.onDestroy();
}
public Observable<Response<MenuResponse>> getMenuByShopAndCategoryId(#NonNull int category_id, #NonNull int shop_id) {
return apiService.getMenuByShopAndCategoryId(category_id,shop_id);
}
public class MenuItemsAdapter extends RecyclerView.Adapter<MenuItemsAdapter.ViewHolder> {
private Context context;
private ArrayList<MenuResponse.MenuRequest> menuItemArrayList;
private ListRowMenuItemsBinding binding;
private MenuItemsAdapterHandler menuItemsAdapterHandler;
public MenuItemsAdapter(Context context, ArrayList<MenuResponse.MenuRequest> menuItemArrayList) {
this.context = context;
this.menuItemArrayList = menuItemArrayList;
}
#NonNull
#Override
public MenuItemsAdapter.ViewHolder onCreateViewHolder(#NonNull ViewGroup viewGroup, int i) {
binding = DataBindingUtil.inflate(LayoutInflater.from(context), R.layout.list_row_menu_items, viewGroup, false);
menuItemsAdapterHandler = new MenuItemsAdapterHandler(context);
binding.setHandler(menuItemsAdapterHandler);
configureLabels();
return new ViewHolder(binding);
}
#Override
public void onBindViewHolder(#NonNull MenuItemsAdapter.ViewHolder viewHolder, int i) {
viewHolder.binding.lblItemName.setText(menuItemArrayList.get(i).getMenuName());
viewHolder.binding.lblPrice.setText("MVR " + String.format("%.2f", Double.valueOf(menuItemArrayList.get(i).getSubTotal())));
if (menuItemArrayList.get(i).getAvailability().equals(Constants.AVAILABLE)){
binding.lblAvailability.set(context, HuqTypogrphyStyle.CAPS_BUTTON_GREEN);
viewHolder.binding.lblAvailability.setText("AVAILABLE");
} else {
binding.lblAvailability.set(context, HuqTypogrphyStyle.CAPS_BUTTON_RED);
viewHolder.binding.lblAvailability.setText("NOT AVAILABLE");
}
viewHolder.binding.setMenuItem(menuItemArrayList.get(i));
viewHolder.binding.executePendingBindings();
}
#Override
public int getItemCount() {
return menuItemArrayList.size();
}
#Override
public int getItemViewType(int position) {
return position;
}
public class ViewHolder extends RecyclerView.ViewHolder {
ListRowMenuItemsBinding binding;
public ViewHolder(#NonNull ListRowMenuItemsBinding listRowMenuItemsBinding) {
super(listRowMenuItemsBinding.getRoot());
this.binding = listRowMenuItemsBinding;
}
}
private void configureLabels() {
binding.lblItemName.set(context, HuqTypogrphyStyle.H2_HEADING);
binding.lblPrice.set(context, HuqTypogrphyStyle.BODY_GRAY);
binding.lblAvailability.set(context, HuqTypogrphyStyle.BODY_GRAY);
}
}
Try moving the api call from on Resume to onCreate.
I have a simple fragment which retrieve data from Firebase database.
I use firebase recycler view to display retrieving data. And after scrolling or screen rotation I can't force recycler view (or linear layout manager) restore scroll position.
I found here some answers but they don't work.
My code is:
public class NewsListFragment extends ParentNewsFragment {
static int color_naval, color_black;
private boolean mProcessLikes = false;
private DatabaseReference mDatabaseLikes;
private DatabaseReference mDatabaseViews;
private FirebaseAuth mAuth;
private int position = 0;
public static NewsListFragment getInstance() {
return new NewsListFragment();
}
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mDatabaseReference = FirebaseDatabase.getInstance().getReference()
.child("App_news");
mDatabaseLikes = FirebaseDatabase.getInstance().getReference().child("news_likes");
mDatabaseViews = FirebaseDatabase.getInstance().getReference().child("news_views");
mAuth = FirebaseAuth.getInstance();
mQuery = mDatabaseReference.orderByChild("pos").startAt("100");
color_naval = getResources().getColor(R.color.colorPrimary);
color_black = getResources().getColor(R.color.colorBlack);
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.rv_choose, container, false);
rv = (RecyclerView) rootView.findViewById(R.id.rv_choose);
lm = new LinearLayoutManager(getActivity());
rv.setLayoutManager(lm);
rv.setHasFixedSize(true);
return rootView;
}
#Override
public void onPause() {
super.onPause();
position = lm.findFirstVisibleItemPosition();
}
#Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
outState.putInt("position", position);
}
#Override
public void onViewStateRestored(#Nullable Bundle savedInstanceState) {
super.onViewStateRestored(savedInstanceState);
if(savedInstanceState != null) {
position = savedInstanceState.getInt("position");
}
}
#Override
public void onResume() {
super.onResume();
if (position != 0) {
lm.scrollToPosition(position);
showToast(position+"");
}
}
#Override
public void onStart() {
super.onStart();
FirebaseRecyclerAdapter<NewsList, NewsListViewHolder> adapter =
new FirebaseRecyclerAdapter<NewsList, NewsListViewHolder>(
NewsList.class,
R.layout.frag_newslist_card_view,
NewsListViewHolder.class,
mQuery
) {
#Override
protected void populateViewHolder(NewsListViewHolder viewHolder, final NewsList model, int position) {
final String post_key = getRef(position).getKey();
viewHolder.setDate(model.getDate()+",");
viewHolder.setTime(model.getTime());
viewHolder.setTitle(model.getTitle());
viewHolder.setImage(getContext(), model.getImage());
viewHolder.setEye(model.getCode());
viewHolder.setThumb(post_key);
viewHolder.thumb.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
mProcessLikes = true;
mDatabaseLikes.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
if (mProcessLikes){
if (dataSnapshot.child(post_key).hasChild(mAuth.getCurrentUser().getUid())){
mDatabaseLikes.child(post_key).child(mAuth.getCurrentUser().getUid())
.removeValue();
mProcessLikes = false;
}
else {
mDatabaseLikes.child(post_key).child(mAuth.getCurrentUser().getUid())
.setValue("like");
mProcessLikes = false;
}
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
});
viewHolder.mView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
mDatabaseViews.addValueEventListener(new ValueEventListener() {
#Override
public void onDataChange(DataSnapshot dataSnapshot) {
if (!dataSnapshot.child(post_key).hasChild(mAuth.getCurrentUser().getUid())) {
mDatabaseViews.child(post_key).child(mAuth.getCurrentUser().getUid())
.setValue("view");
}
}
#Override
public void onCancelled(DatabaseError databaseError) {
}
});
mChooserListener.chooseNews(model.getCode());
}
});
}
};
rv.setAdapter(adapter);
}
public static class NewsListViewHolder extends RecyclerView.ViewHolder {
//some text here
}
}
method showToast in the end shows real number of position but recyclerview starts from the beginning.
any ideas?
Make sure you are not reloading data from the server or wherever you are retrieving data.
Add is not null check in your fragment's onCreateView or activity's onCreate like:
if(savedInstanceState != null){
...
}else{
loadData();
}
Replace your linear layout manager with something similar to the following. I have used this implementation many times when using RecyclerView in fragments. Let me know how it goes
LinearLayoutManager mLayoutManager = new LinearLayoutManager(getActivity());
mLayoutManager.setReverseLayout(true);
mLayoutManager.setStackFromEnd(true);
yourItem.setLayoutManager(mLayoutManager);
I have connected to google api for loaction in android. but i not getting any callback from google api. not getting location.
my code is
public class SplashScreen extends Activity implements GoogleApiClient.ConnectionCallbacks, GoogleApiClient.OnConnectionFailedListener, LocationListener {
public static int SPLASH_TIME_OUT = 3000;
private final String LOG_TAG = "logTagMngr";
private TextView loactionout;
private GoogleApiClient googleApiClient;
private LocationRequest locationRequest;
private LocationManager locationManager;
SharedPreferences sharedPref;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.splash_screen);
sharedPref = getApplicationContext().getSharedPreferences(getString(R.string.preference_file_key), Context.MODE_PRIVATE);
googleApiClient = new GoogleApiClient.Builder(this)
.addApi(LocationServices.API)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.build();
loactionout = (TextView) findViewById(R.id.loactionout);
}
#Override
protected void onResume() {
super.onResume();
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
if (!locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER)) {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setMessage("Turn on location?")
.setCancelable(false)
.setPositiveButton("Turn on Location", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
openWifiSettings();
}
})
.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int which) {
finish();
}
});
AlertDialog alertDialog = builder.create();
alertDialog.show();
} else {
googleApiClient.connect();
}
}
#Override
protected void onStop() {
super.onStop();
if (googleApiClient.isConnected()) {
googleApiClient.disconnect();
}
}
public void openWifiSettings() {
Intent intent = new Intent(android.provider.Settings.ACTION_LOCATION_SOURCE_SETTINGS);
if (intent.resolveActivity(getPackageManager()) != null) {
startActivity(intent);
}
}
#Override
public void onConnected(#Nullable Bundle bundle) {
locationRequest = LocationRequest.create();
locationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
locationRequest.setInterval(500);
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return;
}
LocationServices.FusedLocationApi.requestLocationUpdates(googleApiClient, locationRequest, this);
}
#Override
public void onConnectionSuspended(int i) {
Log.i(LOG_TAG,"Failed");
}
#Override
public void onLocationChanged(Location location) {
Log.i("AAA",location.toString());
loactionout.setText(location.getLatitude()+"");
SharedPreferences.Editor editor = sharedPref.edit();
editor.putString("userLongitude",location.getLongitude()+"");
editor.putString("userLatitude",location.getLatitude()+"");
if(editor.commit()){
Intent i = new Intent(SplashScreen.this, MainActivity.class);
startActivity(i);
finish();
}
}
#Override
public void onConnectionFailed(#NonNull ConnectionResult connectionResult) {
Log.i(LOG_TAG,"Failed");
}
}
i dont know the problem. not getting connection failed on suspended callbacks also. please help me.
I found a tutorial and it looks like this:
package com.djrobotfreak.SVTest;
public class Tutorial2D extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(new Panel(this));
}
class Panel extends SurfaceView implements SurfaceHolder.Callback {
private TutorialThread _thread;
public Panel(Context context) {
super(context);
getHolder().addCallback(this);
_thread = new TutorialThread(getHolder(), this);
}
#Override
public void onDraw(Canvas canvas) {
Bitmap _scratch = BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher);
canvas.drawColor(Color.BLACK);
canvas.drawBitmap(_scratch, 10, 10, null);
}
#Override
public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
// TODO Auto-generated method stub
}
#Override
public void surfaceCreated(SurfaceHolder holder) {
_thread.setRunning(true);
_thread.start();
}
#Override
public void surfaceDestroyed(SurfaceHolder holder) {
// simply copied from sample application LunarLander:
// we have to tell thread to shut down & wait for it to finish, or else
// it might touch the Surface after we return and explode
boolean retry = true;
_thread.setRunning(false);
while (retry) {
try {
_thread.join();
retry = false;
} catch (InterruptedException e) {
// we will try it again and again...
}
}
}
}
class TutorialThread extends Thread {
private SurfaceHolder _surfaceHolder;
private Panel _panel;
private boolean _run = false;
public TutorialThread(SurfaceHolder surfaceHolder, Panel panel) {
_surfaceHolder = surfaceHolder;
_panel = panel;
}
public void setRunning(boolean run) {
_run = run;
}
#Override
public void run() {
Canvas c;
while (_run) {
c = null;
try {
c = _surfaceHolder.lockCanvas(null);
synchronized (_surfaceHolder) {
_panel.onDraw(c);
}
} finally {
// do this in a finally so that if an exception is thrown
// during the above, we don't leave the Surface in an
// inconsistent state
if (c != null) {
_surfaceHolder.unlockCanvasAndPost(c);
}
}
}
}
}
}
and it does not work, no matter what I do. I am trying to convert my code to surfaceview but I cant find any surfaceview programs that even work (besides the android-provided ones). Does anyone know what the error even is saying?
Here is my logcat info: http://shrib.com/oJB5Bxqs
If you get a ClassNotFoundException, you should check the Manifest file.
Click on the Application tab and look on the botton right side under "Attributes for".
If there is a red X mark under your Class Name, then click on the "Name" link and locate the correct class to load.