有一种情况，我有一个具有回收者视图的活动，我有它的适配器，有一个模型类，用于三个文本视图的回收者视图位置，纬度，经度来自数据库。现在我希望第四个回收区域查看距离。距离由另一个类和回调函数中的返回距离计算。我在哪里初始化recyclerview中该类的对象，以便它相对于每个项目的纬度和长度连续更新距离。
返回单纬度，长
的距离的代码 compassManager = new CompassManager(getApplicationContext(), this);
if (isLocationServiceEnabled()) {
Log.i("FloatingViewServie","Location Service Enabled");
// i want to pass latitude and longitude of UserLocations below to
// get distance on each row
compassManager.startNavigating(33.69206669, 73.03208828);
compassManager.getLocation().getLatitude();
compassManager.getLocation().getLongitude();
}
返回连续更新距离的回调方法
@Override
public void onDistanceUpdate(float distance) {
//this distance need to be on recyclerview for each row
}
Recyclerview适配器
public class ActiveLocationsAdapter extends RecyclerView.Adapter<ActiveLocationsAdapter.MyViewHolder> {
public interface OverflowOptions
{
public void edit(int position,UserLocations userLocations);
public void delete();
}
private List<UserLocations> userLocationsList;
FirebaseDatabase database;
DatabaseReference rootRef;
private FirebaseAuth mAuth;
FirebaseUser user;
Context context;
OverflowOptions overflowOptionsCallback;
public ActiveLocationsAdapter(Context context,List<UserLocations> locationsList,OverflowOptions callback) {
this.userLocationsList = locationsList;
database = FirebaseDatabase.getInstance();
rootRef = database.getReference();
mAuth = FirebaseAuth.getInstance();
user = mAuth.getCurrentUser();
this.context=context;
overflowOptionsCallback=callback;
}
@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View itemView = LayoutInflater.from(parent.getContext())
.inflate(R.layout.row_active_locations, parent, false);
return new MyViewHolder(itemView);
}
@Override
public void onBindViewHolder(final MyViewHolder holder, int position) {
// model class that have latitude and longitude for each row
final UserLocations userLocations = userLocationsList.get(position);
Log.i("aaposition",String.valueOf(holder.getAdapterPosition()));
holder.name.setText(userLocations.getName());
// holder.distance.setText(String.valueOf(userLocations.getLatitude()));
// holder.direction.setText(String.valueOf(userLocations.getLongitude()));
holder.overflow.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//creating a popup menu
PopupMenu popup = new PopupMenu(context, holder.overflow);
//inflating menu from xml resource
popup.inflate(R.menu.locations_overflow_menu);
//adding click listener
popup.setOnMenuItemClickListener(new PopupMenu.OnMenuItemClickListener() {
@Override
public boolean onMenuItemClick(MenuItem item) {
switch (item.getItemId()) {
case R.id.action_edit:
overflowOptionsCallback.edit(holder.getAdapterPosition(), userLocations);
break;
case R.id.action_delete:
break;
}
return false;
}
});
//displaying the popup
popup.show();
}
});
}
@Override
public int getItemCount() {
return userLocationsList.size();
}
public class MyViewHolder extends RecyclerView.ViewHolder {
public TextView name, distance, direction;
public ImageView overflow;
public MyViewHolder(View view) {
super(view);
name = (TextView) view.findViewById(R.id.name);
distance = (TextView) view.findViewById(R.id.distance);
direction = (TextView) view.findViewById(R.id.direction);
overflow = (ImageView) view.findViewById(R.id.overflow);
}
}
} 模型类
public class UserLocations {
String id;
String name;
double latitude;
double longitude;
String status;
public UserLocations() {
}
public UserLocations(String id, String name, double latitude, double longitude, String status) {
this.id=id;
this.name = name;
this.latitude = latitude;
this.longitude = longitude;
this.status = status;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public double getLatitude() {
return latitude;
}
public void setLatitude(double latitude) {
this.latitude = latitude;
}
public double getLongitude() {
return longitude;
}
public void setLongitude(double longitude) {
this.longitude = longitude;
}
public String getStatus() {return status;}
public void setStatus(String status) {this.status = status;}
} Recyclerview行
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:focusable="true"
android:paddingLeft="16dp"
android:paddingRight="16dp"
android:paddingTop="10dp"
android:paddingBottom="10dp"
android:clickable="true"
android:background="?android:attr/selectableItemBackground"
android:orientation="vertical">
<TextView
android:id="@+id/name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:textColor="@color/heading"
android:textSize="16dp"
android:textStyle="bold" />
<TextView
android:id="@+id/distance_lable"
android:layout_below="@id/name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="@color/subheading"
android:text="Distance : "/>
<!-- To display distance-->
<TextView
android:id="@+id/distance"
android:layout_below="@id/name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="@color/subheading"
android:layout_toRightOf="@+id/distance_lable"
/>
<TextView
android:layout_below="@id/name"
android:id="@+id/direction_lable"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="@id/distance"
android:textColor="@color/subheading"
android:text=" Direction : "/>
<!-- To display direction-->
<TextView
android:id="@+id/direction"
android:layout_below="@id/name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textColor="@color/subheading"
android:layout_toEndOf="@+id/direction_lable"/>
<ImageButton
android:id="@+id/overflow"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentRight="true"
android:layout_marginRight="5dp"
android:background="@drawable/ic_more_vert_black_24dp"
/>
</RelativeLayout>
具有recyclerview的主要活动
public class MainActivity extends AppCompatActivity
implements CurrentLocationManager.ResultSupplier,NavigationView.OnNavigationItemSelectedListener,ActiveLocationsAdapter.OverflowOptions{
private static final int CODE_DRAW_OVER_OTHER_APP_PERMISSION = 2084;
public static final int REQUEST_FINE_LOCATION = 1;
public static final String TAG= MainActivity.class.getSimpleName();
private PrefManager prefManager;
CurrentLocationManager currentLocationManager;;
private List<UserLocations> userLocationsList = new ArrayList<>();
private RecyclerView recyclerView;
private ActiveLocationsAdapter mAdapter;
FirebaseDatabase database;
DatabaseReference rootRef;
private FirebaseAuth mAuth;
FirebaseUser user;
ProgressDialog progressDoalog;
Context context,interfaceContext;
ImageButton imgBtnSaveLocation;
private double lattitude,longitude;
Switch toggle;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
checkPermissions(this);
permissionCheck();
context=getApplicationContext();
imgBtnSaveLocation=(ImageButton)findViewById(R.id.main_activity_save_btn) ;
progressDoalog = new ProgressDialog(MainActivity.this);
recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
toggle=(Switch)findViewById(R.id.active_locations_switch);
mAdapter = new ActiveLocationsAdapter(getApplicationContext(),userLocationsList,this);
prefManager = new PrefManager(this);
prefManager.setFirstTimeLaunch(false);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
//database reference pointing to root of database
database = FirebaseDatabase.getInstance();
rootRef = database.getReference();
// gives current authenticated user
mAuth = FirebaseAuth.getInstance();
user = mAuth.getCurrentUser();
RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager(getApplicationContext());
recyclerView.setLayoutManager(mLayoutManager);
recyclerView.setItemAnimator(new DefaultItemAnimator());
recyclerView.addItemDecoration(new DividerItemDecoration(this, LinearLayoutManager.VERTICAL));
recyclerView.setAdapter(mAdapter);
progressDoalog.setMessage("Fetching Data. . .");
progressDoalog.show();
// get and update data on View on any change in database
rootRef.child(user.getDisplayName()).child("active_locations").addValueEventListener(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
for (DataSnapshot noteDataSnapshot : dataSnapshot.getChildren()) {
UserLocations locations = noteDataSnapshot.getValue(UserLocations.class);
if(locations.getStatus().equals("active")) {
if (!contains((ArrayList<UserLocations>) userLocationsList, locations)) {
userLocationsList.add(locations);
}
}
}
mAdapter.notifyDataSetChanged();
progressDoalog.dismiss();
}
@Override
public void onCancelled(DatabaseError error) {
// Failed to read value
}
});
// button click that get current location and save to database
imgBtnSaveLocation.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
Log.i(TAG,"onclick");
getLocation();
}
});
// turn the tracking on and off
toggle.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if(isChecked)
Toast.makeText(context, "Toggle on", Toast.LENGTH_SHORT).show();
else
Toast.makeText(context, "Toggle off", Toast.LENGTH_SHORT).show();
}
});
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
drawer.setDrawerListener(toggle);
toggle.syncState();
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
navigationView.setNavigationItemSelectedListener(this);
}
public void permissionCheck()
{
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && !Settings.canDrawOverlays(getApplicationContext())) {
//If the draw over permission is not available open the settings screen
//to grant the permission.
Intent intent = new Intent(Settings.ACTION_MANAGE_OVERLAY_PERMISSION,
Uri.parse("package:" + getPackageName()));
startActivityForResult(intent, CODE_DRAW_OVER_OTHER_APP_PERMISSION);
} else {
}
}
private void requestPermissions(Context context) {
ActivityCompat.requestPermissions((Activity) context,
new String[]{android.Manifest.permission.ACCESS_FINE_LOCATION,android.Manifest.permission.ACCESS_COARSE_LOCATION},
REQUEST_FINE_LOCATION);
}
private boolean checkPermissions(Context context) {
if (ContextCompat.checkSelfPermission(context, android.Manifest.permission.ACCESS_FINE_LOCATION) == PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(context, android.Manifest.permission.ACCESS_COARSE_LOCATION) == PackageManager.PERMISSION_GRANTED) {
return true;
} else {
requestPermissions(context);
return false;
}
}
@Override
public void onBackPressed() {
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
if (drawer.isDrawerOpen(GravityCompat.START)) {
drawer.closeDrawer(GravityCompat.START);
} else {
super.onBackPressed();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@SuppressWarnings("StatementWithEmptyBody")
@Override
public boolean onNavigationItemSelected(MenuItem item) {
// Handle navigation view item clicks here.
int id = item.getItemId();
if (id == R.id.nav_active_locations) {
startActivity(new Intent(getApplicationContext(),ActiveLocationsActivity.class));
} else if (id == R.id.nav_tracked_locations) {
startActivity(new Intent(getApplicationContext(),TrackedLocationsActivity.class));
} else if (id == R.id.nav_slideshow) {
} else if (id == R.id.nav_manage) {
} else if (id == R.id.nav_share) {
AuthUI.getInstance()
.signOut(this)
.addOnCompleteListener(new OnCompleteListener<Void>() {
public void onComplete(@NonNull Task<Void> task) {
// user is now signed out
startActivity(new Intent(getApplicationContext(), SignUpActivity.class));
finish(); }
});
} else if (id == R.id.nav_send) {
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
return true;
}
public void getLocation()
{
currentLocationManager = new CurrentLocationManager(context,this);
currentLocationManager.getUpdatedLocation();
}
/**
* Compares two array list
* @param list
* @param locations
* @return
*/
boolean contains(ArrayList<UserLocations> list, UserLocations locations) {
for (UserLocations item : list) {
if (item.getId().equals(locations.getId())&&item.getName().equals(locations.getName())&&item.getLatitude()==locations.getLatitude()&&item.getLongitude()==locations.getLongitude()&&item.getStatus().equals(locations.getStatus())) {
return true;
}
}
return false;
}
@Override
public void result(double lat, double longi) {
lattitude=lat;
longitude=longi;
Log.i("callback result",String.valueOf(lat)+","+String.valueOf(longi));
}
@Override
public void edit(final int position, final UserLocations userLocations) {
AlertDialog.Builder dialogBuilder = new AlertDialog.Builder(this);
LayoutInflater inflater = this.getLayoutInflater();
final View dialogView = inflater.inflate(R.layout.dialog_edit_location_name, null);
dialogBuilder.setView(dialogView);
final EditText rename = (EditText) dialogView.findViewById(R.id.name);
dialogBuilder.setTitle("Rename Location");
//dialogBuilder.setMessage("hello");
dialogBuilder.setPositiveButton("Done", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
renameLocation(userLocations.getName(),rename.getText().toString());
userLocations.setName(rename.getText().toString());
userLocationsList.set(position, userLocations);
}
});
dialogBuilder.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
//pass
}
});
AlertDialog b = dialogBuilder.create();
b.show();
}
@Override
public void delete() {
}
public void renameLocation(final String name, final String renameLocation) {
Log.i("Interface","renameLocation");
Query renameQuery= rootRef.child(user.getDisplayName()).child("active_locations").orderByChild("name").equalTo(name);
renameQuery.addListenerForSingleValueEvent(new ValueEventListener() {
@Override
public void onDataChange(DataSnapshot dataSnapshot) {
for (DataSnapshot child : dataSnapshot.getChildren()) {
String child_name = (String) child.child("name").getValue();
if (child_name.equals(name)){
child.getRef().child("name").setValue(renameLocation);
Log.i("Rename Location","child renamed");
}
}
}
@Override
public void onCancelled(DatabaseError databaseError) {
}
});
}
}