i want to pass some data from activity to a java class i use intent to pass data from activity to a java class .
// Activity
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_workspace);
worklink = findViewById(R.id.workspace);
button = findViewById(R.id.continu);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String work_link = worklink.getText().toString().trim();
SharedPreferences sharedPref = getSharedPreferences("myKey", MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putString("value", work_link);
editor.apply();
Intent intent = new Intent(workspace.this,BaseURL.class);
startActivity(intent);
}
});
// java class
import android.content.Intent;
public class BaseURL {
String value = getIntent.getExtra("worklink");
}
Create a Global class and create getter setter then set the data you want to pass
public class GlobalData {
public static String status;
public static int getStatus() {
return status;
}
public static void setStatus(String status) {
GlobalData.status = status;
}
}
Related
I had created a app in which i have multiple edittext and one buttonwith recyclerviuew and one button which are setvisibilty as Gone.On Button click it add all my data in my recyclerview list with by chnaging visibality of my recycelr view and my button.In my Custom Adapter i am using a image view to delete the item from postion now i want that if it delete all data from list then it should automatically hide my Button and recyclerview.
//Recycler_view Adapter
public class Myviewholder extends RecyclerView.ViewHolder {
public TextView land_Detail, area_detail, s_no1;
public Button delete;
public Myviewholder(View view) {
super(view);
land_Detail = view.findViewById(R.id.hint31);
area_detail = view.findViewById(R.id.hint21);
s_no1 = view.findViewById(R.id.hint11);
delete = view.findViewById(R.id.hint41);
}
}
public Land_adapters(List<Land_list> land_list, Context context) {
this.laand_list = land_list;
this.context = context;
}
#NonNull
#Override
public Land_adapters.Myviewholder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View itemView = LayoutInflater.from(parent.getContext())
.inflate(R.layout.land_list, parent, false);
return new Myviewholder(itemView);
}
#Override
public void onBindViewHolder(#NonNull Myviewholder holder, final int position) {
final Land_list current_year = laand_list.get(position);
holder.area_detail.setText("District :" + current_year.getDistrict_name() + "\n" + "Village :" + current_year.getVillage_name());
holder.s_no1.setText(String.valueOf(position + 1));
holder.land_Detail.setText("Acre :" + current_year.getAcre() + "\n" + "Kanal :" + current_year.getKanal() + "\n" + "Marla :" + current_year.getMarla());
holder.delete.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Toast.makeText(context, "", Toast.LENGTH_SHORT).show();
Land_list theRemovedItem = laand_list.get(position);
// remove your item from data base
laand_list.remove(position); // remove the item from list
notifyItemRemoved(position); // notify the adapter about the removed item
}
});
}
#Override
public int getItemCount() {
return laand_list.size();
}
//how i am using my recycler in mainactivity class
public void final_step() {
// marla_edit.setError(null);
recyclerView = findViewById(R.id.recycler_view_last1);
mAdapter1 = new Land_Adapter(last_Year1);
recyclerView.setHasFixedSize(true);
RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager(this);
recyclerView.setLayoutManager(mLayoutManager);
recyclerView.setAdapter(mAdapter1);
Land_list last_year1 = new Land_list(land_acre, land_kanal, village_selected1, land_marla, district_selected1, teshil_selected1, block_selected1, block_code, teshil_code1, village_code1, district_code);
last_Year1.add(last_year1);
mAdapter1.notifyDataSetChanged();
if (!(last_Year1.size() == 0)) {
RelativeLayout linearLayout = findViewById(R.id.linear123);
recyclerView.setVisibility(View.VISIBLE);
next_button.setVisibility(View.VISIBLE);
}
else
{
next_button.setVisibility(View.INVISIBLE);
}
// i just want that when it press delete image in recycelr view it should hide my button automatically.
you can use an interface to inform the fragment/activity, the list is empty.
Adapter like as below:
public class CustomAdapter extends RecyclerView.Adapter<CustomViewHolder> {
AdapterListener listener;
public void setListener(AdapterListener listener) {
this.listener = listener;
}
...
#Override
public void onBindViewHolder(#NonNull Myviewholder holder, final int position) {
...
holder.delete.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
...
// remove your item from data base
laand_list.remove(position); // remove the item from list
notifyItemRemoved(position); // notify the adapter about the removed item
if (laand_list.size()==0)
listener.onDataListIsEmpty();
}
});
}
public interface AdapterListener {
void onDataListIsEmpty();
}
}
The Activity/Fragment like as below:
class MyActivity extends Activity implements CustomAdapter.AdapterListener {
CustomAdapter adapter;
#Override
protected void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
...
adapter = new CustomAdapter();
adapter.setListener(this);
...
}
#Override
public void onDataListIsEmpty() {
// set visible or gone views
}
}
hello everyone, I am kind of new using android studio and I am working on my school project. I need to use RecycleVie wand I tried making it but without success.
I use a Object class caled Task whcih have 3 propeties to be shown on the layout but I don't know where is my mistake. the rows which shown as problems are in bold. I will be glad if anyone can help me!
my Object class:
public class Task {
private String material;
private String day;
private String month;
public Task (String material,String day,String month)
{
this.material = material;
this.day = day;
this.month = month;
}
public String getMaterial() {
return material;
}
public void setMaterial(String material) {
this.material = material;
}
public String getDay() {
return day;
}
public void setDay(String day) {
this.day = day;
}
public String getMonth() {
return month;
}
public void setMonth(String month) {
this.month = month;
}
}
the Adapter Code:
public class HomeRecyclerViewAdapter extends RecyclerView.Adapter<HomeRecyclerViewAdapter.ViewHolder> {
private Context mCtx;
private List<Task> tList;
// data is passed into the constructor
public HomeRecyclerViewAdapter(Context mCtx, List<Task> tList) {
this.mCtx = mCtx;
this.tList = tList;
}
// stores and recycles views as they are scrolled off screen
public class ViewHolder extends RecyclerView.ViewHolder {
TextView tvText, tvDateDay, tvDateMonth;
public ViewHolder(View itemView) {
super(itemView);
tvText = itemView.findViewById(R.id.tvText);
tvDateDay = itemView.findViewById(R.id.tvDateDay);
tvDateMonth = itemView.findViewById(R.id.tvDateMonth);
}
}
// inflates the row layout from xml when needed
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
//inflating and returning our view holder
LayoutInflater inflater = LayoutInflater.from(mCtx);
View view = inflater.inflate(R.layout.home_recyclerview_row, null);
return new ViewHolder(view);
}
// binds the data to the TextView in each row
#Override
public void onBindViewHolder(ViewHolder holder, int position) {
Task task = tList.get(position);
**holder.tvText.setText(task.getMaterial());**
}
// allows clicks events to be caught
#Override
public int getItemCount() {
return tList.size();
}
}
and the main code:
public class HomeScreen_activity extends AppCompatActivity implements View.OnClickListener {
List<Task> tList;
RecyclerView homercy;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
setContentView(R.layout.home_screen_layout);
homercy = (RecyclerView) findViewById(R.id.homercy);
homercy.setHasFixedSize(true);
homercy.setLayoutManager(new LinearLayoutManager(this));
// set up the RecyclerView
RecyclerView recyclerView = findViewById(R.id.homercy);
tList = new ArrayList<Task>();
Task t1 = new Task("test","12","05");
tList.add(t1);
**HomeRecyclerViewAdapter adapter = new HomeRecyclerViewAdapter(this,tList);**
recyclerView.setAdapter(adapter);
}
Maybe in onCreateViewHolder(), you must do this:
// inflates the row layout from xml when needed
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.home_recyclerview_row, parent, false);
return new ViewHolder(view);
}
I have a class with the name of SharePrefManager. Here is the code
package com.example.lms02;
public class SharedPrefManager {
private static final String SHARED_PREF_NAME = "volleyregisterlogin";
private static final String KEY_USERNAME = "keyusername";
private static final String KEY_EMAIL = "keyemail";
private static final String KEY_GENDER = "keygender";
private static final String KEY_ID = "keyid";
private static final String KEY_STDID = "keystdid";
private static final String KEY_USER_STATUS = "keyuserstatus";
private static SharedPrefManager mInstance;
private static Context ctx;
private SharedPrefManager(Context context) {
ctx = context;
}
public static synchronized SharedPrefManager getInstance(Context context) {
if (mInstance == null) {
mInstance = new SharedPrefManager(context);
}
return mInstance;
}
//this method will store the user data in shared preferences
public void userLogin(User user) {
SharedPreferences sharedPreferences = ctx.getSharedPreferences(SHARED_PREF_NAME, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.putInt(KEY_ID, user.getId());
editor.putString(KEY_STDID,user.getStdid());
editor.putString(KEY_USERNAME, user.getName());
editor.putString(KEY_EMAIL, user.getEmail());
editor.putString(KEY_GENDER, user.getGender());
editor.putString(KEY_USER_STATUS, user.getStatus());
editor.apply();
}
//this method will checker whether user is already logged in or not
public boolean isLoggedIn() {
SharedPreferences sharedPreferences = ctx.getSharedPreferences(SHARED_PREF_NAME, Context.MODE_PRIVATE);
return sharedPreferences.getString(KEY_USERNAME, null) != null;
}
//this method will give the logged in user
public User getUser() {
SharedPreferences sharedPreferences = ctx.getSharedPreferences(SHARED_PREF_NAME, Context.MODE_PRIVATE);
return new User(
sharedPreferences.getInt(KEY_ID, -1),
sharedPreferences.getString(KEY_STDID, null),
sharedPreferences.getString(KEY_USERNAME, null),
sharedPreferences.getString(KEY_EMAIL, null),
sharedPreferences.getString(KEY_GENDER, null),
sharedPreferences.getString(KEY_USER_STATUS, null)
);
}
//this method will logout the user
public void logout() {
SharedPreferences sharedPreferences = ctx.getSharedPreferences(SHARED_PREF_NAME, Context.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.clear();
editor.apply();
ctx.startActivity(new Intent(ctx, LoginActivity.class));
}
}
I am using Fragments. Here is the code of my Fragment
public class HomeFragment extends Fragment {
TextView txtvwuserid;
User user = SharedPrefManager.getInstance(getContext()).getUser();
public HomeFragment() {
// Required empty public constructor
}
#Override
public void onCreate(#Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
return inflater.inflate(R.layout.fragment_home, container, false);
}
#Override
public void onViewCreated(#NonNull View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
txtvwuserid = getActivity().findViewById(R.id.txtvwstdid);
txtvwuserid.setText("Hy");
}
}
The problem occurs in HomeFragment here
User user = SharedPrefManager.getInstance(getContext()).getUser();
The Error shown is:
java.lang.NullPointerException: Attempt to invoke virtual method 'android.content.SharedPreferences
android.content.Context.getSharedPreferences(java.lang.String, int)' on a null object reference
My Problem is how can i access the values of SharedPrefManager and what does the error means
Problem Solved:
According to the Fragment Life Cycle. we have to place all of our code after the creation of Fragment. What I was doing wrong is Declaring the User object before creation of fragment. Placing it like
#Override
public void onViewCreated(#NonNull View view, #Nullable Bundle savedInstanceState) {
super.onViewCreated(view, savedInstanceState);
user = SharedPrefManager.getInstance(getActivity()).getUser(); //Placing here
}
It Worked For me. Cheers...!!!
I am trying to have a button within a Tab which is part of an activity for uploading images, when clicking the button inside one of the 2 Tabs presented in the activity ( Tab 1 pics, Tab 2 Vid ) the user could choose an image from the device.
My problem is implemneting the onClick Listener and onActivityResult which is not being used when placed after onClick, plus the #Override is being underlined as an error.
I guess i am not implementing the onClick the right way and not sure how to activate onActivityResult the proper way, i would appreciate any guidance;
MainActivty;
public class upload extends AppCompatActivity {
public String UserID;
private static final int REQUEST_SIGNUP = 0;
private DrawerLayout mDrawerLayout;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.upload);
Firebase.setAndroidContext(this);
// Adding Toolbar to Main screen
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
// Setting ViewPager for each Tabs
ViewPager viewPager = (ViewPager) findViewById(R.id.viewpager);
setupViewPager(viewPager);
// Set Tabs inside Toolbar
TabLayout tabs = (TabLayout) findViewById(R.id.tabs);
tabs.setupWithViewPager(viewPager);
}
private void setupViewPager(ViewPager viewPager) {
Adapter adapter = new Adapter(getSupportFragmentManager());
adapter.addFragment(new UploadPictures(), "Pictures");
adapter.addFragment(new UploadVideos(), "Videos");
viewPager.setAdapter(adapter);
}
static class Adapter extends FragmentPagerAdapter {
private final List<Fragment> mFragmentList = new ArrayList<>();
private final List<String> mFragmentTitleList = new ArrayList<>();
public Adapter(FragmentManager manager) {
super(manager);
}
#Override
public Fragment getItem(int position) {
return mFragmentList.get(position);
}
#Override
public int getCount() {
return mFragmentList.size();
}
public void addFragment(Fragment fragment, String title) {
mFragmentList.add(fragment);
mFragmentTitleList.add(title);
}
#Override
public CharSequence getPageTitle(int position) {
return mFragmentTitleList.get(position);
}
}
And here is the Fragment Code;
public class UploadPictures extends android.support.v4.app.Fragment {
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
final RecyclerView recyclerView = (RecyclerView) inflater.inflate(
R.layout.recycler_view, container, false);
ContentAdapter adapter = new ContentAdapter(recyclerView.getContext());
recyclerView.setAdapter(adapter);
recyclerView.setHasFixedSize(true);
recyclerView.setLayoutManager(new LinearLayoutManager(getActivity()));
return recyclerView;
}
public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
public ImageView picture;
public EditText tagEditText;
public Button tagCurLoc, choosePic, uploadContent;
public ViewHolder(LayoutInflater inflater, ViewGroup parent) {
super(inflater.inflate(R.layout.pictue_upload, parent, false));
picture = (ImageView) itemView.findViewById(R.id.imgToUpload);
tagEditText = (EditText) itemView.findViewById(R.id.tagEditText);
tagCurLoc = (Button) itemView.findViewById(R.id.tagCurLoc);
choosePic = (Button) itemView.findViewById(R.id.choosePic);
choosePic.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent galleryIntent = new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
startActivityForResult(galleryIntent, RESULT_LOAD_IMAGE);
}
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (data == null) {
onActivityResult(requestCode, resultCode, data);
Toast.makeText(getActivity().getApplicationContext(), "Canceled ", Toast.LENGTH_SHORT).show();
} else {
if (requestCode == RESULT_LOAD_IMAGE) {
Uri selectedImgPath = data.getData();
picture.setImageURI(selectedImgPath);
RealFilePath = Uri.parse(String.valueOf(selectedImgPath));
Toast.makeText(getActivity().getApplicationContext(), " " + RealFilePath, Toast.LENGTH_SHORT).show();
}
}
}
});
uploadContent = (Button) itemView.findViewById(R.id.uploadContent);
}
}
/**
* Adapter to display recycler view.
*/
public class ContentAdapter extends RecyclerView.Adapter<ViewHolder> {
// Set numbers of List in RecyclerView.
private Context mContext;
public ContentAdapter(Context context) {
this.mContext = context;
}
#Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
return new ViewHolder(LayoutInflater.from(parent.getContext()), parent);
}
#Override
public void onBindViewHolder(final ViewHolder holder, int position) {
}
#Override
public int getItemCount() {
return LENGTH;
}
}
Not sure if the onClick listener for the button should be implemented in the Adapter or the View holder, and from there the issue of onActivityResult cant be used ?
Weel, solved after some more reading and few try outs.
The onClick listener should be implemented at the ViewHolder class followed by
#Override
onActivityResult.
within the onClickListener onActivityResult invoked by;
startActivityForResult(intent, RESULT_LOAD_IMAGE);
and within onActivityResult;
onActivityResult(requestCode, resultCode, data);
Considering all of this taking place in an activity extending Fragment.
My question is how do i send data written in EditText of dialogue box by clicking button and display it on LIstView of Main Activity. ?
public class TaskDetailsActivity extends Activity implements OnClickListener{
String[] timepass= new String[100];
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.taskdetails);
//timepass[0] = "sidd";
/*ListView tasklist= (ListView)findViewById(R.id.listview);
ArrayAdapter<String> adapter = new ArrayAdapter<String>(getApplicationContext(), R.layout.insideaddtask, R.id.tp, timepass);
tasklist.setAdapter(adapter);*/
}
public void addnewtask(View view)
{
showDialog(1);
}
#Override
protected Dialog onCreateDialog(int id)
{
Dialog dialog=null;
switch (id)
{
case 1: dialog = new Dialog(TaskDetailsActivity.this);
dialog.setContentView(R.layout.addtask);
Button task_add_ok = (Button)findViewById(R.id.btn_ok);
task_add_ok.setOnClickListener(new OnClickListener()
{
#Override
public void onClick(View arg0)
{
EditText writetask = (EditText)findViewById(R.id.txt_writetask);
String data = writetask.getText().toString();
timepass[0] = data;
}
});
break;
default:
break;
}
return dialog;
}
#Override
public void onClick(View v)
{
// TODO Auto-generated method stub
}
}
you can use any adapter for this arrayadapter of type string...
and use the button's onclick method to populate the listview...
below link provides a good example...
http://android.amberfog.com/?p=296
www.androidhive.info/2011/10/android-listview-tutorial/