Develop Reference

Disable a button when an event occure in main activity

I have two activities named Main activity and Second Activity. Main activity has an event handler. I need to disable a button in second activity when an event occurs.
Main activity
public void myEventListener(int eventID){
switch (eventID) {
case : 0
// disable button of second activity here
break;
}
}

This is an easy one.
Use SharedPreference of changing data(boolean maybe) in MainAcitivity
Use SharedPreference.OnSharedPreferenceChangeListener in SecondActivity for listening to that specific data and changing button state at runtime in.
MainActivity.java
public class MainActivity extends AppCompatActivity {
SharedPreferences.Editor editor;
public void myEventListener(int eventID){
switch (eventID) {
case 0:
editor = getSharedPreferences("pref",MODE_PRIVATE).edit();
editor.putBoolean("event",true);
break;
}
}
}
SecondActivity
public class SecondActivity extends AppCompatActivity implements SharedPreferences.OnSharedPreferenceChangeListener {
SharedPreferences sharedPreferences;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_first);
}
#Override
protected void onStart() {
super.onStart();
sharedPreferences=getSharedPreferences("pref",MODE_PRIVATE);
sharedPreferences.registerOnSharedPreferenceChangeListener(this);
}
#Override
protected void onStop() {
super.onStop();
sharedPreferences.unregisterOnSharedPreferenceChangeListener(this);
}
#Override
public void onSharedPreferenceChanged(SharedPreferences sharedPreferences, String key) {
if(key.equals("event") && sharedPreferences.getBoolean(key,false))
{
//add your code to disable your button or any action you want
}
}
}

It's very simple to disable a button. Follow the below steps to achieve your problem.
Define a global boolean value as "false"
In onClickEvent override, the boolean value as "true".
Then check with the boolean value as follows
private boolean isClicked = false;
if(isClicked){
button.disabled(true);
} else {
button.disabled(false);
}
Please let me know if you have any issues while applying.

In you First Activity make Boolean static variable.
Example:
FirstActivity
create a Boolean static global variable
public static Boolean clicked = false;
onFirstActivity if Event occurs.
event occurred => clicked = true; otherwise it is false
SecondActivity
in second activity get the value to static boolean from FirstActivity
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (FirstActivity.clicked){
//Do Nothing
}else{
//Perform action
}
}
});

first make reference of second activity and set button visibility GONE or INVISIBLE It's Work
SeconActivity sa; //reference of second activity
public void myEventListener(int eventID){
switch (eventID) {
case : 0
sa.btnofsecondactivity.setVisibilty(View.GONE);
break;
}
}

You can go with LocalBroadCastManager.
in MainActivity wherever you want to trigger the method
LocalBroadcastManager.getInstance(this).sendBroadcast(new Intent("event-occured"));
in SecondActivity register the LocalBroadcastManager and receive it.
public class SecondActivity extends AppCompatActivity {
private BroadcastReceiver mainActivityReceiver;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_second);
mainActivityReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
// do whatever you want to do
Log.d("TAG", "broadcast received");
}
};
LocalBroadcastManager.getInstance(this).registerReceiver(mainActivityReceiver, new IntentFilter("main-activity-initialized"));
}
#Override
protected void onDestroy() {
super.onDestroy();
LocalBroadcastManager.getInstance(this).unregisterReceiver(mainActivityReceiver);
}
Don't forget to unregister the listener in SecondActivity's onDestroy method. Taken reference from here.

Android How to pass data from Activity to Fragment once successful volley request?

I want to pass data from an activity to a fragment via BroadcastReceiver. But I cant get the data in the fragment,cause the onReceive() there not fire up.
In my AppConfig:
public static final String CREATE_POST = "created_post";
In activity A implement all this stuff :
StringRequest request = new StringRequest(Request.Method.POST, AppConfig.MYURL, new Response.Listener<String>(){
#Override
public void onResponse(String response) {
Intent intent = new Intent(AppConfig.CREATE_POST);
intent.putExtra("myId",myId);
intent.putExtra("userId",userId);
intent.putExtra("username",username);
LocalBroadcastManager.getInstance(this).sendBroadcast(intent);
}
In the fragment with should be receive the data I already implement this :
private BroadcastReceiver broadcasterReceiver;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
//..other code here
broadcasterReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
if(intent.getAction().equals(AppConfig.CREATE_POST)){
Log.d("Broadcast","get called")
//HERE I get the intent here
}
}
}
//I already register the boardcast in onResume() and onPause()
#Override
public void onResume() {
super.onResume();
//register the broadcaster
LocalBroadcastManager.getInstance(getActivity()).registerReceiver(broadcasterReceiver,
new IntentFilter(AppConfig.CREATE_POST));
}
#Override
public void onPause() {
super.onPause();
//unregister the broadcaster
LocalBroadcastManager.getInstance(getActivity()).unregisterReceiver(broadcasterReceiver);
}
What I still missing out? In order to make this work.

First of all, create an interface anywhere in your package. For eg -
public interface SyncDataListener {
void refreshDashboard(String myId, String username, String userId);
}
Then in your Activity, create a global declaration and setter/resetter methods like -
private SyncDataListener syncDataListener;
public void setSyncDataListener(SyncDataListener syncDataListener) {
this.syncDataListener = syncDataListener;
}
public void resetSyncDataListener(){
syncDataListener = null;
}
Next in your Fragment implement the above interface and override the method like -
public class DashboardFragment extends Fragment implements SyncDataListener {
#Override
public void refreshDashboard(String myId, String username, String userId) {
//Your code that deals with the data received from activity
}
}
Also in the Fragment's onAttach(Context context) method call the setter method created in the activity like -
#Override
public void onAttach(Context context) {
super.onAttach(context);
((MainActivity) getActivity()).setSyncDataListener(this);
}
Also make sure you reset the listener instance when your Fragment gets destroyed like -
#Override
public void onDestroyView() {
super.onDestroyView();
((MainActivity) getActivity()).resetSyncDataListener();
}
Now whenever you need to send data from Activity to Fragment you can call -
if (syncDataListener != null) {
syncDataListener.refreshDashboard(myId, username, userId);
}

Use this code , this is work in my side :
private BroadcastReceiver broadcasterReceiver;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
//..other code here
broadcasterReceiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
if(intent.getAction().equals(AppConfig.CREATE_POST)){
Log.d("Broadcast","get called")
//HERE I get the intent here
}
}
}
//I already register the boardcast in onResume() and onPause()
#Override
public void onResume() {
super.onResume();
//register the broadcaster
LocalBroadcastManager.getInstance(getActivity()).registerReceiver(broadcasterReceiver,
new IntentFilter(AppConfig.CREATE_POST));
}
#Override
public void onPause() {
super.onPause();
//unregister the broadcaster
LocalBroadcastManager.getInstance(getActivity()).unregisterReceiver(broadcasterReceiver);
}
use this code to register the broadcast

Data does not reload automatically in a Fragment inside ViewPager

I have 2 activities: Activity1 (MainActivity) and Activity2.
Activity1 has 3 Fragments: Fragment_1, Fragment_2 and Fragment_3.
I want to change data of Fragment_3 according to action performed on Activity2.
My problem is that, I call Activity2 from Fragment_2 and do something there (in Activity2) and hit back to Fragment_2 and View Fragmnet_3, there are no change in data of Fragment_3 (Fragment_3' data should be changed according to action performed on Activity2).
But when I choose Fragment_1 and then choose Fragment_3, data of it is changed according to action on Activity_2.
I want I call Activity2 from Fragment_2 and do something there (in Activity2) and hit back to Fragment_2 and View Fragmnet_3, data will change.
How to do that?

in your fragment add this method this method always call when your fragment if visible on screen.
#Override
public void setUserVisibleHint(boolean isVisibleToUser) {
super.setUserVisibleHint(isVisibleToUser);
if(isVisibleToUser)
{
//your changes here
}
}

i made it! Use BroadCastRecevier!
frament3:
public class MyFragment3 extends Fragment {
String key;
private TextView tv;
#Override
public void onResume() {
//register LocalBroadCastReceiver
LocalBroadcastManager lm = LocalBroadcastManager.getInstance(getContext());
MyReceiver receiver = new MyReceiver();
IntentFilter filter = new IntentFilter();
filter.addAction("com.action.sodemo");
lm.registerReceiver(receiver,filter);
super.onResume();
}
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, #Nullable Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_item3,container,false);
tv = (TextView) view.findViewById(R.id.tv_3);
return view;
}
class MyReceiver extends BroadcastReceiver{
#Override
public void onReceive(Context context, Intent intent) {
key = intent.getStringExtra("value");
tv.setText(key);
}
}
}
Activity2:
public class Activity_2 extends AppCompatActivity {
private LocalBroadcastManager lm;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_activity_2);
lm=LocalBroadcastManager.getInstance(this);
Button btn = (Button) findViewById(R.id.btn_choose);
btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
//send value to fragment3
Intent intent = new Intent("com.action.sodemo");
intent.putExtra("value","change");
lm.sendBroadcast(intent);
}
});
}
}

EventBus does not register event on new activity

I have implemented an otto bus example. It works fine, but ONLY on the second time I visit the activity.
For example, when I load the app and hit the secret message button I am taken to the activity but the toast does not show. Then I hit the back button to return to the MainActivity and hit the show secret message button again and when I am taken to the secret message activity the toast is displayed. I realize it works the second time because I have created a leak by not unregistering the event.
Is there something I am missing about the logic?
MainActivity:
public class MainActivity extends AppCompatActivity {
Button buttonSecretMessage;
Intent intentToMessage;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
intentToMessage = new Intent(MainActivity.this, SecretMessageActivity.class);
buttonSecretMessage = (Button) findViewById(R.id.buttonSecretMessage);
buttonSecretMessage.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
EventBus.getInstance().post(new MakeMySecretMessageEvent());
startActivity(intentToMessage);
}
});
}
}
Secret Message Activity:
public class SecretMessageActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_secret_message);
}
#Subscribe
public void getMySecretMessage(MakeMySecretMessageEvent event){
Toast.makeText(this, event.getMessage(), Toast.LENGTH_SHORT).show();
}
#Override
protected void onStart(){
super.onStart();
EventBus.getInstance().register(this);
}
#Override
protected void onStop() {
super.onStop();
//EventBus.getInstance().unregister(this);
}
}
MakeMySecretMessageEvent:
public class MakeMySecretMessageEvent {
public MakeMySecretMessageEvent() {
}
public String getMessage() {
String message = "YOU ARE AWESOME!";
return message;
}
}
EventBus:
public final class EventBus extends Bus{
private static final EventBus Bus = new EventBus();
public static Bus getInstance() {
return Bus;
}
private EventBus() {
}
}

You can send sticky event using EventBus library. It allows you to send events to component which is not created yet.
You`ll find more info here.

Here EventBus has applied in wrong scenario, when you can simply send data via intent or bundle. Which is more reliable in communication with one activity with another. You will never ever receive event on first click, as event fire is instant and your activity creation will take some time accordingly.
So try to use bundle or intent to setup communication b/w to activity one after another.

Thanks to contributors I now have a better understanding of the activity life cycle and how it fits in with event bus. That is you cannot send an event from the MainActivity to its children, but the other way around instead. Below reflects how to implement an otto event bus to pass a simple object from an activity back to the main activity. Hopefully someone else can find this useful :) And if this can be improved upon please comment. Thanks.
Main Activity:
public class MainActivity extends AppCompatActivity {
Button buttonSecretMessage;
Intent intentToMessage;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
EventBus.getInstance().register(this);
intentToMessage = new Intent(MainActivity.this, SecretMessageActivity.class);
buttonSecretMessage = (Button) findViewById(R.id.buttonSecretMessage);
buttonSecretMessage.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
startActivity(intentToMessage);
}
});
}
public MakeMySecretMessageEvent event;
#Subscribe
public void getMySecretMessage(MakeMySecretMessageEvent event) {
Toast.makeText(this, event.getMessage(), Toast.LENGTH_SHORT).show();
}
protected void onStop() {
super.onStop();
if(event != null ){
EventBus.getInstance().unregister(this);
}
}
}
SecretMessageActivity (this is where the secret message is created)
public class SecretMessageActivity extends AppCompatActivity {
Button buttonClickToMeToSeeMessage;
Intent intentToMain;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_secret_message);
intentToMain = new Intent(SecretMessageActivity.this, MainActivity.class);
buttonClickToMeToSeeMessage = (Button) findViewById(R.id.buttonClickToMeToSeeMessage);
buttonClickToMeToSeeMessage.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
MakeMySecretMessageEvent makeMySecretMessageEvent = new MakeMySecretMessageEvent();
EventBus.getInstance().post(makeMySecretMessageEvent);
startActivity(intentToMain);
}
});
}
}
MakeMySecretMessageEvent
public class MakeMySecretMessageEvent {
public MakeMySecretMessageEvent() {
}
public String getMessage() {
String message = "YOU ARE AWESOME!";
return message;
}
}
EventBus:
public final class EventBus extends Bus{
private static final EventBus Bus = new EventBus();
public static Bus getInstance() {
return Bus;
}
private EventBus() {
}
}

pass string from fragment main activity to fragments activity in viewpager

i wanna pass a string to all fragment(child) from fragment activity (main), may be this picture can explain what exactly what i want to do
https://dl.dropboxusercontent.com/u/57465028/SC20140205-163325.png
so, from above picture...i wanna pass a string from edittext by press a button to all activity in viewpager....how could i do that?
i tried to follow this code https://stackoverflow.com/a/12739968/2003393 but it can't solved my problem..
please help me...i'm stuck
thank in advance.
here is my code from fragment activity (MainActivity)
public class Swipe_Menu extends FragmentActivity {
//String KeyWord;
//private static final String KEYWORD = "keyword";
private ViewPager _mViewPager;
private ViewPagerAdapter _adapter;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.swipe_menu_image);
Button Back = (Button)findViewById(R.id.account);
ImageButton Search = (ImageButton)findViewById(R.id.search);
EditText Keyword = (EditText)findViewById(R.id.keyword);
final String KeyWord = Keyword.getText().toString();
/**
* Back button click event
* */
Back.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
finish();
}
});
setUpView();
setTab();
}
protected void sendValueToFragments(String value) {
// it has to be the same name as in the fragment
Intent intent = new Intent("my_package.action.UI_UPDATE");
intent.putExtra("UI_KEY", KeyWord );
LocalBroadcastManager.getInstance(this).sendBroadcast(intent);
}
and here is my fragment (Child Activity)
public class Store_Swipe extends Fragment {
public static final String ACTION_INTENT = "my_package.action.UI_UPDATE";
String KeyWord;
private TextView kata_keyword;
protected BroadcastReceiver receiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
if(ACTION_INTENT.equals(intent.getAction())) {
String value = intent.getStringExtra("UI_KEY");
updateUIOnReceiverValue(value);
}
}
};
private void updateUIOnReceiverValue(String value) {
// you probably want this:
KeyWord = value;
}
public static Fragment newInstance(Context context) {
Store_Swipe f = new Store_Swipe();
return f;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
IntentFilter filter = new IntentFilter(ACTION_INTENT);
LocalBroadcastManager.getInstance(getActivity()).registerReceiver(receiver, filter);
}
#Override
public void onDestroy() {
LocalBroadcastManager.getInstance(getActivity()).unregisterReceiver(receiver);
super.onDestroy();
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
/*Bundle bundle = this.getArguments();
KeyWord = bundle.getString("keyword");*/
View view = inflater.inflate(R.layout.store_swipe, container, false);
init(view);
return view;
}
void init(View view) {
kata_keyword = (TextView) view.findViewById(R.id.keyword);
//ImageView image = (ImageView) view.findViewById(R.id.image_error);
kata_keyword.setText(KeyWord);
}
}

You don't have access directly to your fragments that reside in ViewPager so you can't reference them directly.
What I am doing in these cases is send a broadcast message from Activity to Fragments. For this reason register a BroadcatReceiver in the fragment (either in onCreate or onCreateView - your decision)m, set a custom action for that receiver (ex. "my_package.actions.internal.BROADCAST_ACTION"), don't forget to unregister the receiver from complementary method.
When you want to send a message from activity, create an intent with above mentioned action, add the string in intent extra and send the broadcast.
In your receiver's onReceive method (within the fragment), get the String from intent paramter and there you have the string.
Makes sense?
EDIT: To provide some code, below are the changes that I would make for fragment:
public class Store_Swipe extends Fragment {
public static final String ACTION_INTENT = "my_package.action.UI_UPDATE";
protected BroadcastReceiver receiver = new BroadcastReceiver() {
#Override
public void onReceive(Context context, Intent intent) {
if(ACTION_INTENT.equals(intent.getAction())) {
String value = intent.getStringExtra("UI_KEY");
updateUIOnReceiverValue(value);
}
}
};
private void updateUIOnReceiverValue(String value) {
// you probably want this:
kata_keyword.setText(value);
}
String KeyWord;
private TextView kata_keyword;
public static Fragment newInstance(Context context) {
Store_Swipe f = new Store_Swipe();
return f;
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
IntentFilter filter = new IntentFilter(ACTION_INTENT);
LocalBroadcastManager.getInstance(getActivity()).registerReceiver(receiver, filter);
}
#Override
public void onDestroy() {
LocalBroadcastManager.getInstance(getActivity()).unregisterReceiver(receiver);
super.onDestroy();
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
Bundle bundle = this.getArguments();
KeyWord = bundle.getString("keyword");
View view = inflater.inflate(R.layout.store_swipe, container, false);
init(view);
return view;
}
void init(View view) {
kata_keyword = (TextView) view.findViewById(R.id.keyword);
ImageView image = (ImageView) view.findViewById(R.id.image_error);
kata_keyword.setText(KeyWord);
}
}
And this code I would have from activity, the parameter is the value from EditText:
protected void sendValueToFragments(String value) {
// it has to be the same name as in the fragment
Intent intent = new Intent("my_package.action.UI_UPDATE");
intent.putExtra("UI_KEY", value);
LocalBroadcastManager.getInstance(this).sendBroadcast(intent);
}
You would call this from the click listener that you would set in onCreate:
findViewById(R.id.button_id).setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
String valueThatYouWantToSend = null; /// just the value
sendValueToFragments(valueThatYouWantToSend);
}
});

// I think this solution will solved your issue
// In Main activity put your code -----------------------------------
public void onPageSelected(int position)
{
System.out.println("nilesh");
PageOneFragment f = new PageOneFragment();
f.getText();
PageTwoFragment ff = new PageTwoFragment();
ff.setText();
}
//in General Class ------------------------------------------------
public class General
{
public static String name="";
}
// first Fragment ---------------------------------------------
public void getText()
{
General.name = edittext.getText().toString();
}
// second Fragment ----------------------------------------------
public void setText()
{
System.out.println("name**" + General.name);
tv.setText(General.name);
}