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Android Fragments - Edit Text Of Another Fragment

So I have made a simple heating text control app and it all works with permissions and all of that but it uses 2 fragments and inside them are two textboxes which I want to have the same text in -- phone number. I cannot get the edittext in rel2 to be changed by rel1.
Rel 1:
package com.danielkern.relswitcher;
import android.content.Context;
import android.content.SharedPreferences;
import android.support.v4.app.Fragment;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import android.telephony.SmsManager;
import static android.content.SharedPreferences.*;
/**
* Created by Daniel Kern on 03/01/2018.
*/
public class Rel1 extends Fragment{
Button BtnHOFF, BtnHON, BtnHST, saveB;
EditText txtPhoneNo;
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.rel1, container, false);
final View view2 = inflater.inflate(R.layout.rel2, container, false);
final SharedPreferences sharedPref = this.getActivity().getSharedPreferences("settings", Context.MODE_PRIVATE);
String savedNo = sharedPref.getString("phoneNo", "07599070551");
BtnHOFF = (Button) view.findViewById(R.id.Hoff);
BtnHON = (Button) view.findViewById(R.id.Hon);
BtnHST = (Button) view.findViewById(R.id.Hstatus);
txtPhoneNo = (EditText) view.findViewById(R.id.editText);
saveB = (Button) view.findViewById(R.id.saveB);
((EditText) view.findViewById(R.id.editText)).setText(savedNo);
Toast.makeText(getActivity().getApplicationContext(), savedNo, Toast.LENGTH_LONG).show();
BtnHOFF.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
sendMsg("#REL1=ON", txtPhoneNo.getText().toString());
}
});
BtnHON.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
sendMsg("#REL1=OFF", txtPhoneNo.getText().toString());
Log.i(getActivity().toString(), "Done!");
}
});
BtnHST.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
sendMsg("#STATUS", txtPhoneNo.getText().toString());
}
});
saveB.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
sharedPref.edit().putString("phoneNo", txtPhoneNo.getText().toString());
Log.i("me", "Saved!");
Toast.makeText(getActivity().getApplicationContext(),
"Saved!",
Toast.LENGTH_LONG).show();
((EditText) view2.findViewById(R.id.editText)).setText(txtPhoneNo.getText().toString());
}
});
return view;
}
public void sendMsg(String msg, String num){
try {
SmsManager smsManager = SmsManager.getDefault();
smsManager.sendTextMessage(num, null, msg, null, null);
Toast.makeText(getActivity().getApplicationContext(), "SMS Sent!",
Toast.LENGTH_LONG).show();
} catch (Exception e) {
Toast.makeText(getActivity().getApplicationContext(),
"SMS failed, contact administrator!",
Toast.LENGTH_LONG).show();
e.printStackTrace();
}
}
#Override
public void onPause() {
super.onPause();
}
}
Rel 2:
package com.danielkern.relswitcher;
import android.content.Context;
import android.content.SharedPreferences;
import android.content.SharedPreferences.Editor;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v4.app.Fragment;
import android.telephony.SmsManager;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
/**
* Created by Daniel Kern on 03/01/2018.
*/
public class Rel2 extends Fragment {
Button BtnWOFF, BtnWON, BtnWST, saveB;
EditText txtPhoneNo;
#Nullable
#Override
public View onCreateView(LayoutInflater inflater, #Nullable ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.rel2, container, false);
final View view1 = inflater.inflate(R.layout.rel1, container, false);
final SharedPreferences sharedPref = this.getActivity().getSharedPreferences("settings", Context.MODE_PRIVATE);
String savedNo = sharedPref.getString("phoneNo", "07599070551");
BtnWOFF = (Button) view.findViewById(R.id.Woff);
BtnWON = (Button) view.findViewById(R.id.Won);
BtnWST = (Button) view.findViewById(R.id.Wstatus);
saveB = (Button) view.findViewById(R.id.saveB);
txtPhoneNo = (EditText) view.findViewById(R.id.editText);
((EditText) view.findViewById(R.id.editText)).setText(savedNo);
Toast.makeText(getActivity().getApplicationContext(), savedNo, Toast.LENGTH_LONG).show();
BtnWOFF.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
sendMsg("#REL2=ON", txtPhoneNo.getText().toString());
}
});
BtnWON.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
sendMsg("#REL2=OFF", txtPhoneNo.getText().toString());
}
});
BtnWST.setOnClickListener(new View.OnClickListener() {
public void onClick(View view) {
sendMsg("#STATUS", txtPhoneNo.getText().toString());
}
});
saveB.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
sharedPref.edit().putString("phoneNo", txtPhoneNo.getText().toString());
((EditText) view1.findViewById(R.id.editText)).setText(txtPhoneNo.getText().toString());
Log.d("me", "Saved!");
}
});
return view;
}
public void sendMsg(String msg, String num){
try {
SmsManager smsManager = SmsManager.getDefault();
smsManager.sendTextMessage(num, null, msg, null, null);
Toast.makeText(getActivity().getApplicationContext(), "SMS Sent!",
Toast.LENGTH_LONG).show();
} catch (Exception e) {
Toast.makeText(getActivity().getApplicationContext(),
"SMS failed, contact administrator!",
Toast.LENGTH_LONG).show();
e.printStackTrace();
}
}
#Override
public void onPause() {
super.onPause();
}
}
Rel 1 xml:
<?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="match_parent">
<Button
android:id="#+id/Hon"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true"
android:layout_marginTop="44dp"
android:text="Heating ON (REL1 OFF)"
android:textSize="18sp"
android:textStyle="bold" />
<Button
android:id="#+id/Hoff"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_below="#+id/Hon"
android:layout_marginTop="13dp"
android:text="Heating OFF (REL1 ON)"
android:textSize="18sp"
android:textStyle="bold" />
<Button
android:id="#+id/Hstatus"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_below="#+id/Hoff"
android:layout_marginTop="15dp"
android:text="STATUS"
android:textSize="18sp"
android:textStyle="bold" />
<TextView
android:id="#+id/texts"
android:layout_width="match_parent"
android:layout_height="200dp"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="46dp"
android:text="Coming Soon!"
android:textSize="24sp" />
<EditText
android:id="#+id/editText"
android:text="07599070551"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:ems="10"
android:inputType="phone" />
<Button
android:id="#+id/saveB"
android:layout_width="wrap_content"
android:layout_height="40dp"
android:layout_alignBaseline="#+id/editText"
android:layout_alignBottom="#+id/editText"
android:layout_alignParentEnd="true"
android:text="Save" />
</RelativeLayout>
Rel 2 XML:
<?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="match_parent">
<Button
android:id="#+id/Won"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true"
android:layout_marginTop="44dp"
android:text="Water ON (REL2 OFF)"
android:textSize="18sp"
android:textStyle="bold" />
<Button
android:id="#+id/Woff"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_below="#+id/Won"
android:layout_marginTop="13dp"
android:text="Water OFF (Rel2 On)"
android:textSize="18sp"
android:textStyle="bold" />
<Button
android:id="#+id/Wstatus"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentStart="true"
android:layout_below="#+id/Woff"
android:layout_marginTop="15dp"
android:text="STATUS"
android:textSize="18sp"
android:textStyle="bold" />
<TextView
android:id="#+id/texts"
android:layout_width="match_parent"
android:layout_height="200dp"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="46dp"
android:text="Coming Soon!"
android:textSize="24sp" />
<EditText
android:id="#+id/editText"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:ems="10"
android:inputType="phone" />
<Button
android:id="#+id/saveB"
android:layout_width="wrap_content"
android:layout_height="40dp"
android:layout_alignBaseline="#+id/editText"
android:layout_alignBottom="#+id/editText"
android:layout_alignParentEnd="true"
android:text="Save" />
</RelativeLayout>
EDIT:
I would like the edit text in Rel2 to change when I press save in rel1 therefore the phone number boxes will always be the same.
rel1
EDIT 2:
I have fixed the shared prefs issue but I would still like to know if anyone can make the textboxes the same wherether that is on text update or on save button press.

There are two ways you can do this.
Using Interface
Create an interface with a method something like TextChangeListener and declare a method onTextChange(String text).
interface TextChangeListener{
void onTextChange(String number);
}
Implement the interface in the HostActivity
class HostActivity extends Activity implements TextChangeListener{
...
void onTextChange(String number){
secondFragment.updateNumber(number)
}
...
}
In FirstFragment call the activity using the implmented interface in the afterTextChanged() listener of TextWatcher
class FirstFragment extends Fragment{
private TextChangeListener activity;
#Override
public onAttach(Context context){
if(context instanceof TextChangeListener){
activity = (TextChangeListener) context;
}
}
phNumEditText.addTextChangedListener(new TextWatcher() {
#Override
public void afterTextChanged(Editable s) {
activity.onTextChange(s.toString);
}
...
);
...
}
In SecondFragment on receiving the call from activity, update the EditText with new data.
class SecondFragment extends Fragment{
...
public void updateNumber(String number){
editText.setText(number);
}
}
Using EventBus
Use EventBus to post an event from FirstFragment. The event will contain the data to be populated in SecondFragment. The SecondFragment will Subscribe to the event and on receiving the event the data will be populate into the EditText.

How to add strings from editText to a listView

I have a MainActivity with a ListView and an add Button. When the user clicks the add Button it takes you to another activity the CreateActivity for you to enter in data or strings into the editText boxes. After that you click the create Button and it adds the strings to the ListView it shows up, but every time I try to add another item to the ListView it just overrides the first item and doesn't add on to the ListView.
MainActivity.java with listView and add button
package com.example.brian.inventoryapp;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import static android.R.layout.simple_list_item_1;
public class MainActivity extends AppCompatActivity {
Button addButton;
ListView itemListView;
public static ArrayList<String> arrayList;
public static ArrayAdapter arrayAdapter;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Bundle editTextData = getIntent().getExtras();
if(editTextData != null){
itemListView = (ListView)findViewById(R.id.itemListView);
String data = editTextData.getString("data");
arrayList = new ArrayList<String>();
arrayList.add(data);
arrayAdapter = new ArrayAdapter(this, android.R.layout.simple_list_item_1, arrayList);
itemListView.setAdapter(arrayAdapter);
if(data != ""){
arrayAdapter.notifyDataSetChanged();
}
}
addButton = (Button) findViewById(R.id.addButton);
addButton.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, CreateActivity.class);
startActivity(intent);
}
});
}
}
activity_main xml with listView and add button
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.example.brian.inventoryapp.MainActivity"
android:weightSum="1">
<Button
android:text="Add"
android:layout_width="wrap_content"
android:layout_height="58dp"
android:layout_alignParentBottom="true"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:id="#+id/addButton" />
<ListView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="#+id/itemListView"
/>
</RelativeLayout>
CreateActivity.java with four editText boxes and create button
package com.example.brian.inventoryapp;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import static com.example.brian.inventoryapp.R.id.editTextItem;
public class CreateActivity extends AppCompatActivity {
EditText editTextItem;
EditText editTextModel;
EditText editTextSerial;
EditText editTextID;
Button createButton;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_create);
getIntent();
editTextItem = (EditText)findViewById(R.id.editTextItem);
editTextModel = (EditText)findViewById(R.id.editTextModel);
editTextSerial = (EditText)findViewById(R.id.editTextSerial);
editTextID = (EditText)findViewById(R.id.editTextID);
createButton = (Button) findViewById(R.id.createButton);
createButton.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v) {
String item = "";
item = editTextItem.getText().toString().trim() +
editTextModel.getText().toString().trim() +
editTextSerial.getText().toString().trim() +
editTextID.getText().toString().trim();
Intent intent = new Intent(getApplicationContext(), MainActivity.class);
intent.putExtra("data", item);
startActivity(intent);
}
});
}
}
activity_create xml with the four editText boxes and the create button
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/activity_create"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="#dimen/activity_vertical_margin"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="com.example.brian.inventoryapp.CreateActivity">
<TextView
android:text="Item Name"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:id="#+id/textView" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="textPersonName"
android:ems="10"
android:layout_below="#+id/textView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:id="#+id/editTextItem" />
<TextView
android:text="Model Number"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginTop="18dp"
android:id="#+id/textView2"
android:layout_below="#+id/editTextItem"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="textPersonName"
android:ems="10"
android:layout_below="#+id/textView2"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:id="#+id/editTextModel" />
<TextView
android:text="Serial Number"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/editTextModel"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="18dp"
android:id="#+id/textView3" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="textPersonName"
android:ems="10"
android:layout_below="#+id/textView3"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:id="#+id/editTextSerial" />
<ImageButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:srcCompat="#mipmap/ic_launcher"
android:layout_below="#+id/editTextID"
android:layout_centerHorizontal="true"
android:layout_marginTop="64dp"
android:id="#+id/imageButton" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="textPersonName"
android:ems="10"
android:id="#+id/editTextID"
android:layout_below="#+id/editTextSerial"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="18dp" />
<TextView
android:text="ID Number"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/textView4"
android:layout_below="#+id/editTextSerial"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<Button
android:text="Create"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/createButton"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true" />
</RelativeLayout>

every time you restart the MainActivity, it is be created, the onCreate method was executed .one method you can use the comment method：use startactivityforResult;
you can read this question how to manage startactivityforResult.the second method is to set MainActivity model to SingleInstance.

You are starting MainActivity over and over again, clearing all data previously loaded.
Try this solution
Main activity:
package com.example.brian.inventoryapp;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import static android.R.layout.simple_list_item_1;
public class MainActivity extends AppCompatActivity {
public static final int CREATE_REQUEST = 1;
private Button addButton;
private ListView itemListView;
private ArrayList<String> arrayList;
private ArrayAdapter<String> arrayAdapter;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
itemListView = (ListView) findViewById(R.id.itemListView);
addButton = (Button) findViewById(R.id.addButton);
arrayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, arrayList);
itemListView.setAdapter(arrayAdapter);
addButton = (Button) findViewById(R.id.addButton);
addButton.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, CreateActivity.class);
startActivityForResult(intent, CREATE_REQUEST);
}
});
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == CREATE_REQUEST) {
if (resultCode == RESULT_OK) {
String item = data.getStringExtra("data");
arrayList.add(item);
arrayAdapter = new ArrayAdapter<String>(this, android.R.layout.simple_list_item_1, arrayList);
itemListView.setAdapter(arrayAdapter);
}
}
}
}
In your CreateActivity change createButton listener to this one:
createButton.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v) {
String item = "";
item = editTextItem.getText().toString().trim() +
editTextModel.getText().toString().trim() +
editTextSerial.getText().toString().trim() +
editTextID.getText().toString().trim();
Intent intent = new Intent();
intent.putExtra("data", item);
setResult(RESULT_OK, intent);
finish();
}
});

Yes it will assume as if the MainActivity is started for the first time so you should use startActivityForResult() method instead of startActivity().This will continue your MainActivity and do not override your list View.

android fragments problems

i wrote a toDO list for my android class. It totally works , but now i want to display the todo list on a fragment ( so it can be its on tab). but when i tried making the fragment , i get a weird error when i try to run it. apparently the error comes from my main activity . so the way i have it set up is that, my main activity has a button that opens the fragment that has all the TOdolist stuff in it. but when i run it on my phone i get a unfortunately TodoList ha stopped as soon as it runs. the error is get is
06-10 22:21:51.284 5302-5302/com.example.mike.todolist D/AbsListView﹕ Get MotionRecognitionManager
06-10 22:21:51.304 5302-5302/com.example.mike.todolist D/AndroidRuntime﹕ Shutting down VM
06-10 22:21:51.304 5302-5302/com.example.mike.todolist W/dalvikvm﹕ threadid=1: thread exiting with uncaught exception (group=0x417c2898)
06-10 22:21:51.314 5302-5302/com.example.mike.todolist E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.NullPointerException
at com.example.mike.todolist.ToDoFragment.onCreateView(ToDoFragment.java:38)
at android.app.Fragment.performCreateView(Fragment.java:1699)
at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:903)
at android.app.FragmentManagerImpl.moveToState(FragmentManager.java:1075)
at android.app.BackStackRecord.run(BackStackRecord.java:682)
at android.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1455)
at android.app.FragmentManagerImpl$1.run(FragmentManager.java:441)
at android.os.Handler.handleCallback(Handler.java:730)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:5455)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:525)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1187)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:1003)
at dalvik.system.NativeStart.main(Native Method)
my main activity look like
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.app.ListActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Button;
import android.view.View;
public class MainActivity extends ListActivity {
#Override
public void onCreate(Bundle savedInstanceState) {
setContentView(R.layout.todo_main_activity);
super.onCreate(savedInstanceState);
Button button1 = (Button) findViewById(R.id.fragButton);
button1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
FragmentManager fragmentManager = getFragmentManager();
FragmentTransaction
=fragmentTransaction=fragmentManager.beginTransaction();
ToDoFragment fragment = new ToDoFragment();
fragmentTransaction.add(R.id.mainLL, fragment);
fragmentTransaction.commit();
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.menu, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
return true;
}
}
My main activity xml is
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:id="#+id/mainLL"
android:layout_height="fill_parent">
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="frag"
android:id="#+id/fragButton"
android:layout_alignParentTop="true"
android:layout_alignParentEnd="true"
android:onClick="fragButtonClick"
android:layout_gravity="center_horizontal" />
</LinearLayout>
Fragment.java
package com.example.mike.todolist;
import android.app.AlertDialog;
import android.app.FragmentManager;
import android.app.FragmentTransaction;
import android.app.ListFragment;
import android.content.ContentValues;
import android.content.DialogInterface;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListAdapter;
import android.widget.SimpleCursorAdapter;
import android.widget.TextView;
import com.example.mike.todolist.db.Contract;
import com.example.mike.todolist.db.DBHelper;
/**
* Created by mike on 6/10/15.
*/
public class ToDoFragment extends ListFragment {
public ListAdapter listAdapter;
public DBHelper helper;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
final View view=inflater.inflate(R.layout.fragmentlayout, container, false);
// Inflate the layout for this fragment
update();
Button doneButton = (Button)view.findViewById(R.id.doneButton);
doneButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
View v = (View) view.getParent();
TextView taskTextView = (TextView) v.findViewById(R.id.taskTextView);
String task = taskTextView.getText().toString();
String sql = String.format("DELETE FROM %s WHERE %s = '%s'",
Contract.TABLE_NAME,
Contract.Columns.TASK,
task);
helper = new DBHelper(getActivity());
SQLiteDatabase sqlDB = helper.getWritableDatabase();
sqlDB.execSQL(sql);
update();
}
});
Button addButton = (Button)view.findViewById(R.id.AddButton);
addButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View arg0) {
switch (R.id.add_task) {
case R.id.add_task:
AlertDialog.Builder builder = new AlertDialog.Builder(getActivity());
builder.setTitle("Add a task");
builder.setMessage("What would you like to do?");
final EditText input = new EditText(getActivity());
builder.setView(input);
builder.setPositiveButton("Add", new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialogInterface, int i) {
String task = input.getText().toString();
helper = new DBHelper(getActivity());
SQLiteDatabase db = helper.getWritableDatabase();
ContentValues cv = new ContentValues();
cv.clear();
cv.put(Contract.Columns.TASK, task);
db.insertWithOnConflict(Contract.TABLE_NAME, null, cv, SQLiteDatabase.CONFLICT_IGNORE);
update();
}
});
builder.setNegativeButton("Cancel", null);
builder.create().show();
}
}
});
return view;
}
private void update() {
helper = new DBHelper(getActivity());
SQLiteDatabase sqlDB = helper.getReadableDatabase();
Cursor cursor = sqlDB.query(Contract.TABLE_NAME,
new String[]{Contract.Columns._ID, Contract.Columns.TASK},
null, null, null, null, null);
listAdapter = new SimpleCursorAdapter(
getActivity(),
R.layout.task_view,
cursor,
new String[]{Contract.Columns.TASK},
new int[]{R.id.taskTextView},
0
);
this.setListAdapter(listAdapter);
}
}
and this is my fragmentlayout
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="fill_parent"
android:id="#+id/mainLL"
android:layout_height="fill_parent">
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#android:id/list"
android:layout_weight="1"
android:layout_margin="5dp"
android:background="#color/grey"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Add Task"
android:id="#+id/AddButton"
android:layout_alignParentTop="true"
android:layout_alignParentEnd="true"
android:onClick="AddButtonClick"
android:layout_gravity="center_horizontal" />
</LinearLayout>
taskview
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
android:layout_width="fill_parent"
android:layout_height="fill_parent"
xmlns:android="http://schemas.android.com/apk/res/android">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/taskTextView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:textSize="20dp"
android:textColor="#color/black"
android:typeface="sans"
android:layout_toLeftOf="#+id/doneButton"
android:layout_alignBottom="#+id/doneButton"
android:gravity="center_vertical"
android:textStyle="bold"
android:layout_alignTop="#+id/doneButton" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Done"
android:id="#+id/doneButton"
android:layout_alignParentTop="true"
android:layout_alignParentEnd="true"
android:onClick="DoneButtonClick"
/>
</RelativeLayout>

According to android developers official website (HERE)
ListActivity has a default layout that consists of a single, full-screen list in the center of the screen. However, if you desire, you can customize the screen layout by setting your own view layout with setContentView() in onCreate(). To do this, your own view MUST contain a ListView object with the id "#android:id/list" (or list if it's in code)
for example:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingLeft="8dp"
android:paddingRight="8dp">
<ListView android:id="#android:id/list"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#00FF00"
android:layout_weight="1"
android:drawSelectorOnTop="false"/>
<TextView android:id="#android:id/empty"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#FF0000"
android:text="No data"/>
</LinearLayout>
So either add a listview to your list activity xml or if you don't need a list view in your activity then simply use FragmentActivity to hold fragments.There is no point in using ListActivity unless it holds a ListView.

Your class is extending to a ListActivity which requires the ListView element in the xml. Your purpose be best served by extending your MainActivity class to Activity and fragments (if any) to Fragments class....

Add an list view to your xml with id android.R.id.list
<ListView
android:id="#android:id/list"
android:layout_width="match_parent"
android:layout_height="match_parent" />
add this xml to your layout

use Activity or FragmentActivity instead of ListActivity
if you want to use ListActivity see here once. you can use ListActivity without setting content view (setContentView()). you can directly setAdapter. or else use your own layout having one ListView with id as "#android:id/list"
EDIT :
public void onClick(View arg0) {
TextView taskTextView = (TextView) view.findViewById(R.id.taskTextView);//directly use 'view' if 'R.id.taskTextView'it present in 'view'
String task = taskTextView.getText().toString();
String sql = String.format("DELETE FROM %s WHERE %s = '%s'",
Contract.TABLE_NAME,
Contract.Columns.TASK,
task);
helper = new DBHelper(getActivity());
SQLiteDatabase sqlDB = helper.getWritableDatabase();
sqlDB.execSQL(sql);
update();
}

making toast for validate edit text when i push a button

im tired to try this thing,can help me find out my solution.
I try to validate Edittext if edittext filed empty when i push a button will show a toast message.
this my layout.xml
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent"
android:layout_height="match_parent" android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
android:paddingBottom="#dimen/activity_vertical_margin" tools:context=".MyActivity"
android:id="#+id/relativeLayout">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Panjang"
android:id="#+id/textView"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_gravity="right|left" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="number"
android:ems="20"
android:id="#+id/editTextPanjang"
android:layout_below="#+id/textView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:maxLength="10"
android:hint="Panjang"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Lebar"
android:id="#+id/textView2"
android:layout_below="#+id/editTextPanjang"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_gravity="right|left"
/>
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="number"
android:ems="20"
android:id="#+id/editTextLebar"
android:layout_below="#+id/textView2"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:maxLength="10"
android:hint="Lebar"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Hitung Luas"
android:id="#+id/buttonHitungLuas"
android:layout_below="#+id/editTextLebar"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:onClick="hitugLuas"
/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Luas"
android:id="#+id/textView3"
android:layout_below="#id/buttonHitungLuas"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"/>
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="number"
android:ems="20"
android:id="#+id/editTextLuas"
android:layout_below="#id/textView3"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/editTextLuas"
android:id="#+id/buttonClear"
android:text="#string/btn_clear"
/>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_toRightOf="#+id/buttonClear"
android:layout_below="#+id/editTextLuas"
android:id="#+id/buttonExit"
android:text="Exit"
/>
</RelativeLayout>
this my java
package com.example.aan.myfirstapp;
import android.content.Context;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class MyActivity extends ActionBarActivity {
private EditText edtPanjang;
private EditText edtLebar;
private EditText edtLuas;
private Button btnHitungLuas;
private Button btnClear;
private Button btnExit;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_my);
initUI();
initEvent();
}
private void initUI(){
edtPanjang = (EditText) findViewById(R.id.editTextPanjang);
edtLebar = (EditText) findViewById(R.id.editTextLebar);
edtLuas = (EditText) findViewById(R.id.editTextLuas);
btnHitungLuas = (Button) findViewById(R.id.buttonHitungLuas);
btnClear = (Button) findViewById(R.id.buttonClear);
btnExit = (Button) findViewById(R.id.buttonExit);
}
private void initEvent() {
btnHitungLuas.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
hitungLuas();
}
}
btnClear.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
clearData();
}
});
btnExit.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View paramView) {
MyActivity.this.finish();
}
});
}
private void hitungLuas(){
int panjang = Integer.parseInt(edtPanjang.getText().toString());
int lebar = Integer.parseInt(edtLebar.getText().toString());
int luas = panjang*lebar;
edtLuas.setText(luas+"");
}
private void clearData(){
edtLuas.setText("");
edtLebar.setText("");
edtPanjang.setText("");
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_my, 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);
}
}
Sory for my bad english
log chat when i run the emulator
03-12 09:29:21.784 1710-2323/com.google.process.gapps E/Backup﹕ [LegacyBackupAccountManager] Fail to get legacy transport context.
android.content.pm.PackageManager$NameNotFoundException: Application package com.google.android.backup not found
at android.app.ContextImpl.createPackageContextAsUser(ContextImpl.java:2139)
at android.app.ContextImpl.createPackageContext(ContextImpl.java:2115)
at android.content.ContextWrapper.createPackageContext(ContextWrapper.java:658)
at com.google.android.gms.backup.am.<init>(SourceFile:47)
at com.google.android.gms.backup.a.a(SourceFile:65)
at com.google.android.gms.backup.c.a(SourceFile:39)
at com.google.android.gms.backup.b.a(SourceFile:67)
at com.google.android.gms.backup.b.a(SourceFile:39)
at com.google.android.gms.backup.BackupAccountNotifierService.onHandleIntent(SourceFile:76)
at android.app.IntentService$ServiceHandler.handleMessage(IntentService.java:65)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.os.HandlerThread.run(HandlerThread.java:61)

You need to handle onClick of the button in this manner and show a toast if the edittext is empty
if(editText.getText().toString().trim().length()==0){
Toast.makeText(getApplicationContext(), "field is empty",
Toast.LENGTH_LONG).show();
}else{
//your code here
}

If you want to check for empty EditText.. try TextUtils for it.
Example
if (TextUtils.isEmpty(edtText.getText().toString().trim())) {
Toast.makeText(getBaseContext(),
"Empty", Toast.LENGTH_SHORT)
.show();
} else {
Toast.makeText(getBaseContext(),
"Not Empty", Toast.LENGTH_SHORT)
.show();
}

How to pass user input from one activity to another in Android

I'm creating a basic conversion app which converts the users input from km-knots or vice versa. At present it displays the result in the same place as where the user initially type in their figure. I'm wondering how is it possible to display the result in a new activity? Currently I've only managed to make it appear, as I said, in the same place as where the user initially type in their figure and a second afterwards the second activity pops up. What am I missing here? Please look at my code, thanks:
MainActivity.java
package winfield.joe.wind.v1;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.view.View;
import android.widget.EditText;
import android.widget.RadioButton;
import android.widget.Toast;
public class MainActivity extends Activity {
// public var
private EditText text;
// default func
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Toast.makeText(this, "onCreate!", Toast.LENGTH_LONG).show();
setContentView(R.layout.activity_main);
// findViewById = Finds a view that was identified by the id attribute
// from the XML that was processed in onCreate(Bundle).
// (EditText) = typecast
text = (EditText) findViewById(R.id.userInput);
}
//Will be executed by clicking on the calculate button because we assigned "calc" to the "onClick" Property
public void calc(View view) {
RadioButton toKilometers = (RadioButton) findViewById(R.id.toKilometers);
RadioButton toKnots = (RadioButton) findViewById(R.id.toKnots);
if (text.getText().length() == 0) {
// if the text field is empty show the message "enter a valid number" via toast message
Toast.makeText(this, "enter a valid number", Toast.LENGTH_LONG).show();
} else {
int result = R.string.userInput;
Intent i = new Intent(MainActivity.this, SecondActivity.class);
putExtra("userInput", result);
startActivity(i);
// parse input Value from Text Field
double inputValue = Double.parseDouble(text.getText().toString());
// convert to...
if (toKilometers.isChecked()) {
text.setText(String.valueOf(convertToKM(inputValue)));
// uncheck "to km" Button
toKilometers.setChecked(false);
// check "to knots" Button
toKnots.setChecked(true);
} else { /* if toKnots button isChecked() */
text.setText(String.valueOf(convertToKnots(inputValue)));
// uncheck "to knots" Button
toKnots.setChecked(false);
// check "to km" Button
toKilometers.setChecked(true);
}
}
}
private void putExtra(String string, int result) {
// TODO Auto-generated method stub
}
private double convertToKM(double inputValue) {
// convert knots to km
return (inputValue * 1.8);
}
private double convertToKnots(double inputValue) {
// convert km to knots
return (inputValue * 0.539956803);
}
}
SecondActivity.java
package winfield.joe.wind.v1;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
public class SecondActivity extends Activity {
Bundle extras = getIntent().getExtras();
int result = extras.getInt("results");
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_second);
}
//onClick GoBack method assigned to the Go Back? button which returns the user to main activity from the second activity
public void GoBack(View view) {
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Are you sure?");
// set dialog message
builder .setCancelable(false)
.setPositiveButton("Convert Again",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int id) {
//You return to Main Activity
Intent intent = new Intent(SecondActivity.this, MainActivity.class);
startActivity(intent);
}
})
.setNeutralButton("Back to Home",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int id) {
//You return to the home page
Intent intent = new Intent(Intent.ACTION_MAIN);
intent.addCategory(Intent.CATEGORY_HOME);
startActivity(intent);
}
})
.setNegativeButton("View Results",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int id) {
// if this button is clicked, just close the dialog box and do nothing
dialog.cancel();
}
});
AlertDialog alert = builder.create();
alert.show();
}
}
activity_main.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/LinearLayout1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentBottom="true"
android:layout_alignParentEnd="true"
android:background="#color/bgColor"
android:orientation="vertical">
<!--TITLE-->
<TextView
android:id="#+id/titleMain"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginTop="22dp"
android:gravity="center"
android:text="#string/titleMain"
android:textColor="#color/textColor"
android:textColorHint="#color/textColor"
android:textColorLink="#ffffff"
android:textSize="30sp" />
<!--USER-INPUT-->
<EditText
android:id="#+id/userInput"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:ems="10"
android:hint="#+string/userInput"
android:inputType="numberDecimal"
android:paddingEnd="40dp"
android:paddingStart="20dp"
android:paddingTop="30dp" >
<requestFocus />
</EditText>
<!--TWO RADIO BUTTONS-->
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:paddingLeft="10dp"
android:paddingRight="10dp">
<!--toKNOTS-->
<RadioButton
android:id="#+id/toKnots"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginStart="10dp"
android:layout_marginTop="10dp"
android:layout_weight="0.04"
android:checked="true"
android:text="#string/toKnots" />
<!--toKM-->
<RadioButton
android:id="#+id/toKilometers"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginEnd="20dp"
android:layout_marginTop="10dp"
android:text="#string/toKilometers" />
</LinearLayout>
<!--CALCULATE-->
<Button
android:id="#+id/valueCalc"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginEnd="10dp"
android:layout_marginStart="10dp"
android:layout_marginTop="30dp"
android:onClick="calc"
android:text="#string/valueCalc" />
</LinearLayout>
activity_second.xml
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/LinearLayout1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:layout_alignParentBottom="true"
android:layout_alignParentEnd="true"
android:background="#color/bgColor"
android:orientation="vertical"
tools:context="${relativePackage}.${activityClass}" >
<!-- TITLE -->
<TextView
android:id="#+id/titleResults"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginTop="24dp"
android:gravity="center"
android:text="#string/titleResults"
android:textColor="#color/textColor"
android:textColorHint="#color/textColor"
android:textColorLink="#ffffff"
android:textSize="25sp" />
<EditText
android:id="#+id/results"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_margin="20dp"
android:layout_marginTop="30dp"
android:ems="10"
android:hint="#string/results"
android:inputType="numberDecimal"
android:textColorHint="#color/textColor" >
<requestFocus />
</EditText>
<Button
android:id="#+id/GoBack"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_marginTop="40dp"
android:text="#string/GoBack"
android:onClick="GoBack" />
</LinearLayout>
LOGCAT
03-09 12:27:35.692: E/AndroidRuntime(2911): java.lang.RuntimeException: Unable to start activity ComponentInfo{winfield.joe.wind.v1/winfield.joe.wind.v1.SecondActivity}: java.lang.NullPointerException
03-09 12:27:35.692: E/AndroidRuntime(2911): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
03-09 12:27:45.262: E/AndroidRuntime(2934): java.lang.RuntimeException: Unable to start activity ComponentInfo{winfield.joe.wind.v1/winfield.joe.wind.v1.SecondActivity}: java.lang.NullPointerException
03-09 12:27:45.262: E/AndroidRuntime(2934): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
03-09 12:29:52.172: E/AndroidRuntime(2989): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{winfield.joe.wind.v1/winfield.joe.wind.v1.SecondActivity}: java.lang.NullPointerException
03-09 12:29:52.172: E/AndroidRuntime(2989): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
03-09 12:32:29.322: E/AndroidRuntime(3056): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{winfield.joe.wind.v1/winfield.joe.wind.v1.SecondActivity}: java.lang.NullPointerException
03-09 12:32:29.322: E/AndroidRuntime(3056): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
03-09 12:36:29.872: E/AndroidRuntime(3112): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{winfield.joe.wind.v1/winfield.joe.wind.v1.SecondActivity}: java.lang.NullPointerException
03-09 12:36:29.872: E/AndroidRuntime(3112): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
03-09 12:44:25.022: E/AndroidRuntime(3172): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{winfield.joe.wind.v1/winfield.joe.wind.v1.SecondActivity}: java.lang.NullPointerException
03-09 12:44:25.022: E/AndroidRuntime(3172): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
03-09 12:53:38.802: E/AndroidRuntime(3242): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{winfield.joe.wind.v1/winfield.joe.wind.v1.SecondActivity}: java.lang.NullPointerException
03-09 12:53:38.802: E/AndroidRuntime(3242): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
03-09 13:19:58.122: E/AndroidRuntime(3299): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{winfield.joe.wind.v1/winfield.joe.wind.v1.SecondActivity}: java.lang.NullPointerException
03-09 13:19:58.122: E/AndroidRuntime(3299): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)

If you want to pass any content from one activity to another, you can do it by using putExtra with intent, it will send data from one activity to another, and in another activity get that data by using getExtras.
To send data,
String str = "value";
Intent launchResult = new Intent(MainActivity.this, SecondActivity.class);
putExtra("key", str);
startActivity(launchResult);
To receive data in another activity,
Bundle extras = getIntent().getExtras();
String str = extras.getStr("key");
Edit:
In my answer key is any unique value that must remain same in both Sender Activity and Receiver Activity.
You are getting the error because you have passed a string value where you had to pass key, and the key in receiver activity in not matching either.
See the change below, it should work
MainActivity.class
int result = R.string.userInput;
Intent i = new Intent(MainActivity.this, SecondActivity.class);
putExtra("userInput", result);
startActivity(i);
SecondActivity.class
Bundle extras = getIntent().getExtras();
int result = extras.getInt("userInput");

Use below code to pass values from one Activity to Another
Intent launchResult = new Intent(MainActivity.this, SecondActivity.class);
launchResult.putExtra("output",result);