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.
Related
This question already has answers here:
Unfortunately MyApp has stopped. How can I solve this?
(23 answers)
Closed 4 years ago.
I am trying to get an input from user and then covert it into double and divide it by 1000 and then set the value in a textview but i while running the app, the app closes and says Unfortunately the app has stopped.
Here's my MainActivity.java file :
package com.blogspot.techtutorialsajen.androiddevelopmentpractice;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.os.Bundle;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity{
private Button btn1;
private EditText get;
private TextView result;
#Override
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn1 = (Button)findViewById(R.id.btn1);
result = (TextView)findViewById(R.id.result);
get = (EditText)findViewById(R.id.get);
final double value = Double.parseDouble(get.getText().toString()) / 1000;
btn1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
result.setText(String.valueOf(value));
}
});
}
}
And My activity_main.xml file :
?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">
<EditText
android:id="#+id/get"
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:hint="#string/enter_a_number"
android:layout_marginTop="48dp"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<Button
android:id="#+id/btn1"
android:text="#string/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="#+id/result"
android:layout_centerHorizontal="true"
android:layout_marginBottom="28dp" />
<TextView
android:id="#+id/result"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:textSize="20pt"
android:text="0"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true" />
</RelativeLayout>
Well, Your app is crashes because of java.lang.RuntimeException:java.lang.NumberFormatException: Invalid double: ""
that means you are trying to convert empty string to Double.
So, Because the EditText is empty your app is crashes and I have re-write your code so that you can copy-paste.
Here is your MainActivity.Java
package com.blogspot.techtutorialsajen.androiddevelopmentpractice;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.os.Bundle;
import android.widget.EditText;
import android.widget.TextView;
public class MainActivity extends AppCompatActivity{
private Button btn1;
private EditText get;
private TextView result;
#Override
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btn1 = (Button)findViewById(R.id.btn1);
result = (TextView)findViewById(R.id.result);
get = (EditText)findViewById(R.id.get);
btn1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (get.getText().toString().isEmpty()) {
Toast.makeText(MainActivity .this, "Please input something", Toast.LENGTH_LONG).show();
} else {
final double value = Double.parseDouble(get.getText().toString()) / 1000;
result.setText(String.valueOf(value));
}
}
});
}
}
and here is your activity_main.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">
<EditText
android:id="#+id/get"
android:layout_height="wrap_content"
android:layout_width="match_parent"
android:hint="#string/enter_a_number"
android:layout_marginTop="48dp"
android:inputType="number"
android:layout_alignParentTop="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<Button
android:id="#+id/btn1"
android:text="#string/button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_above="#+id/result"
android:layout_centerHorizontal="true"
android:layout_marginBottom="28dp" />
<TextView
android:id="#+id/result"
android:layout_height="wrap_content"
android:layout_width="wrap_content"
android:textSize="20pt"
android:text="0"
android:layout_centerVertical="true"
android:layout_centerHorizontal="true" />
</RelativeLayout>
I have added android:inputType="number" property to your EditText so that, now on, it will only take Number from the user.
From your xml file and activity code, it clearly says your edittext is empty while launching app.
And you are using this code in oncreate()
final double value = Double.parseDouble(get.getText().toString()) / 1000;
which throws java.lang.NumberFormatException: empty String
You can change your code like,
btn1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if(!get.getText().toString().isEmpty)
final double value = Double.parseDouble(get.getText().toString()) / 1000;
result.setText(String.valueOf(value));
}
});
}
so i have a project where im implementing a google sign in, i followed this tutorial on how to do that, but when i did, all my XML files appear blank. i made changes to the original MainActivity.java and the activity_main.xml file. i woudl think that only the activity_main.xml would be affected, but all of my XML files appear blank. when i try to run the app, i get
"Error:Content is not allowed in prolog.
" and
"Execution failed for task '.app:builderInfoDebugLoader'"
this is my activity main where i implement the google sign in:
package com.example.mayankthakur.personalprojecttrial2;
import android.content.Context;
import android.content.Intent;
import android.content.SharedPreferences;
import android.net.Uri;
import android.support.annotation.NonNull;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.view.Window;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.LinearLayout;
import android.widget.TextView;
import com.bumptech.glide.Glide;
import com.google.android.gms.auth.api.Auth;
import com.google.android.gms.auth.api.signin.GoogleSignInAccount;
import com.google.android.gms.auth.api.signin.GoogleSignInOptions;
import com.google.android.gms.auth.api.signin.GoogleSignInResult;
import com.google.android.gms.auth.api.signin.SignInAccount;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.SignInButton;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.common.api.ResultCallback;
import com.google.android.gms.common.api.Status;
import org.w3c.dom.Text;
public class MainActivity extends AppCompatActivity implements View.OnClickListener, GoogleApiClient.OnConnectionFailedListener {
private LinearLayout prof_section;
private Button SignOut;
private SignInButton SignIn;
private TextView Name,Email;
private ImageView Prof_Picture;
private Button continueBut;
private static final int REQ_CODE = 9001;
String name;
Intent nameSave;
private GoogleApiClient mGoogleApiClient;
public static final String prefsName = "com.example.mayankthakur.personalprojecttrial2";
private static final String TAG = "MainActivity";
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
this.requestWindowFeature(Window.FEATURE_NO_TITLE);
setContentView(R.layout.activity_main);
prof_section = (LinearLayout) findViewById(R.id.prof_section);
SignOut = (Button) findViewById(R.id.logoutBtn);
SignIn = (SignInButton) findViewById(R.id.gSignIn);
Name = (TextView) findViewById(R.id.nameSpace);
Email = (TextView) findViewById(R.id.emailSpace);
Prof_Picture = (ImageView) findViewById(R.id.profilePicture);
continueBut = (Button) findViewById(R.id.button2);
continueBut.setOnClickListener(this);
SignOut.setOnClickListener(this);
SignIn.setOnClickListener(this) ;
prof_section.setVisibility(View.GONE);
continueBut.setVisibility(View.GONE);
GoogleSignInOptions gso = new GoogleSignInOptions.Builder(GoogleSignInOptions.DEFAULT_SIGN_IN)
.requestEmail()
.build();
mGoogleApiClient = new GoogleApiClient.Builder(this)
.enableAutoManage(this, this)
.addApi(Auth.GOOGLE_SIGN_IN_API, gso)
.build();
}
#Override
public void onClick (View v) {
switch (v.getId()) {
case R.id.gSignIn:
signIn();
break;
case R.id.logoutBtn:
signOut();
break;
/*// This is the shared preference
SharedPreferences.Editor prefs = getSharedPreferences(prefsName, MODE_PRIVATE).edit();
//adding a value to the preference
prefs.putString("name", name);
prefs.apply();
nameSave = new Intent(MainActivity.this, Activity2.class);
MainActivity.this.startActivity(nameSave);
*/
}
}
#Override
public void onConnectionFailed (#NonNull ConnectionResult connectionResult){
}
private void signIn() {
Intent signInIntent = Auth.GoogleSignInApi.getSignInIntent(mGoogleApiClient);
startActivityForResult(signInIntent, REQ_CODE );
}
private void signOut(){
Auth.GoogleSignInApi.signOut(mGoogleApiClient).setResultCallback(new ResultCallback<Status>() {
#Override
public void onResult(#NonNull Status status) {
updateUI(false);
}
});
}
private void handleReuslt(GoogleSignInResult result){
if(result.isSuccess())
{
GoogleSignInAccount acct = result.getSignInAccount();
String personName = acct.getDisplayName();
String personEmail = acct.getEmail();
String imgUrl = acct.getPhotoUrl().toString();
String personId = acct.getId();
Uri personPhoto = acct.getPhotoUrl();
Name.setText(personName);
Email.setText(personEmail);
Glide.with(this).load(imgUrl).into(Prof_Picture);
updateUI(true);
}
else
{
updateUI(false);
}
}
private void updateUI(boolean isLogin){
if(isLogin)
{
prof_section.setVisibility(View.VISIBLE);
SignIn.setVisibility(View.GONE);
}
else
{
prof_section.setVisibility(View.GONE);
SignIn.setVisibility(View.VISIBLE);
}
}
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if(requestCode == REQ_CODE)
{
GoogleSignInResult result = Auth.GoogleSignInApi.getSignInResultFromIntent(data);
handleReuslt(result);
}
}
}
this is my XML file where i added the buttons and stuff for the google sign in:\
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout 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:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/activity_main"
android:orientation="vertical"
tools:context="com.example.mayankthakur.personalprojecttrial2.MainActivity">
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:id="#+id/prof_section"
android:layout_marginLeft="20dp"
android:layout_marginTop = "50dp"
android:weightSum="1">
<ImageView
android:id="#+id/profilePicture"
android:layout_width="90dp"
android:layout_height="100dp"
android:layout_marginRight="20dp"
android:layout_marginTop="20dp"
android:src="#drawable/photo"
android:layout_weight="0.25" />
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:orientation="vertical"
android:layout_marginLeft="28dp"
android:layout_marginTop="20dp">
<TextView
android:id="#+id/nameSpace"
android:layout_width="166dp"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:gravity="center_horizontal"
android:text="Name Display"
android:textSize="20dp"
android:textStyle="bold" />
<TextView
android:id="#+id/emailSpace"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:gravity="center"
android:text="Email Display"
android:textSize="14dp"
android:textStyle="bold" />
<Button
android:id="#+id/logoutBtn"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Logout" />
</LinearLayout>
</LinearLayout>
<com.google.android.gms.common.SignInButton
android:id="#+id/gSignIn"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="50dp"
android:layout_marginRight="50dp"
android:layout_marginTop="60dp">
</com.google.android.gms.common.SignInButton>
<TextView
android:id="#+id/textView"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Please Sign in in order to make use of all of the features of the app"
android:textAlignment="center"
android:textSize="20dp"
android:layout_marginTop="30dp"
android:layout_marginLeft="30dp"
android:layout_marginRight="30dp"/>
<Button
android:id="#+id/button2"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Continue"
android:layout_marginRight="50dp"
android:layout_marginLeft="50dp"
android:layout_marginTop="50dp"/>
</LinearLayout>
any help would be greatly appreciated, and if any of you require any more code please do ask
thanks in advance!
This question already has answers here:
How do I pass data between Activities in Android application?
(53 answers)
Closed 6 years ago.
I am trying to take text that was generated in one activity, that was concatenated, "MainActivity.java," and display it on screen using another activity, "DICS.java." I am having trouble figuring out how to do that.
MainActivity.java
package com.example.tristan.a1p1n1;
import android.content.Intent;
import android.net.Uri;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
public class MainActivity extends AppCompatActivity {
public final static String EXTRA_MESSAGE = "com.example.tristan.a1p1n1.MESSAGE";
/**
* ATTENTION: This was auto-generated to implement the App Indexing API.
* See https://g.co/AppIndexing/AndroidStudio for more information.
*/
private GoogleApiClient client;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
// ATTENTION: This was auto-generated to implement the App Indexing API.
// See https://g.co/AppIndexing/AndroidStudio for more information.
client = new GoogleApiClient.Builder(this).addApi(AppIndex.API).build();
}
public void sendMessage(View view)
{
Intent intent = new Intent(this, DICS.class);
EditText editText = (EditText) findViewById(R.id.editText);
EditText editText2 = (EditText) findViewById(R.id.editText2);
String message = editText.getText().toString() + editText2.getText().toString();
intent.putExtra(EXTRA_MESSAGE, message);
startActivity(intent);
}}
activity_main.xml
<?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.tristan.a1p1n1.MainActivity">
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="textPersonName"
android:text="Enter a String"
android:ems="10"
android:layout_below="#+id/textView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:id="#+id/editText" />
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:inputType="textPersonName"
android:text="Enter a String"
android:ems="10"
android:id="#+id/editText2"
android:layout_below="#+id/editText"
android:layout_alignRight="#+id/editText"
android:layout_alignEnd="#+id/editText"
android:layout_marginRight="11dp"
android:layout_marginEnd="11dp"
android:layout_marginTop="13dp" />
<Button
android:text="+"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/editText2"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginTop="23dp"
android:id="#+id/button"
android:onClick="sendMessage" />
</RelativeLayout>
DICS.java
package com.example.tristan.a1p1n1;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
/**
* Created by Tristan on 2/11/2017.
*/
public class DICS extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.dics);
}
}
dics.xml
<?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">
<TextView
android:text="#+id/sendMessage"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/textView2" />
</LinearLayout>
Intent intent = getIntent();
String dataGet= intent.getExtras().getString("EXTRA_MESSAGE");
Get the intent and then proceed to get the string from the intent
Intent intent = getIntent();
String stringFromIntent = intent.getStringExtra(MainActivity.EXTRA_MESSAGE);
I don't know what is wrong with this code. I am trying to make a to do list app. I am new to Android and Java programming so please don't get mad if this is a simple errror.It gives me the error in the title.
Here is my 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=".MainActivity">
<ListView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="#+id/lvItems"
android:layout_alignParentTop="true"
android:layout_alignParentStart="true" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Add"
android:id="#+id/button"
android:layout_alignParentBottom="true"
android:layout_alignParentEnd="true"
android:onClick="onAddItem"/>
<EditText
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/etNewItem"
android:hint="Enter a new item"
android:layout_alignParentStart="true"
android:layout_alignTop="#+id/button"
android:layout_toStartOf="#+id/button" />
</RelativeLayout>
Here is my Java:
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ListView;
import java.util.ArrayList;
public class MainActivity extends Activity {
private ArrayList<String> items;
private ArrayAdapter<String> itemsAdapter;
private ListView lvItems;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//EditText
final EditText etTask = (EditText) findViewById(R.id.etNewItem);
final String Task = etTask.getText().toString();
lvItems = (ListView) findViewById(R.id.lvItems);
items = new ArrayList<String>();
itemsAdapter = new ArrayAdapter<String>(this,
android.R.layout.simple_list_item_1, items);
lvItems.setAdapter(itemsAdapter);
items.add("First Item");
items.add("Second Item");
//Button
Button btn = (Button) findViewById(R.id.button);
//Adding a Task
//OnClickListeners
btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
items.add(etTask.getText().toString());
etTask.setText("");
}
});
}
}
Since you made a change to adapter after ListView was populated, Listview must be informed to repopulate the views with new values by calling notifydatasetchanged() on your adapter ie,
items.add(etTask.getText().toString());
((ArrayAdapter)lvItems.getAdapter()).notifydatasetchanged();
etTask.setText("");
My problem is when I click bSA button I encounter error and the activity closes.
java.lang.runtimeexception unable to start activity componentinfo ...
here is my code
Data.java :
package com.example.myapp;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.TextView;
public class Data extends Activity implements View.OnClickListener {
Button start, startFor;
EditText sendET;
TextView gotAnswer;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.get);
initialize();
}
private void initialize() {
start = (Button) findViewById(R.id.bSA);
startFor = (Button) findViewById(R.id.bSAFR);
sendET = (EditText) findViewById(R.id.etSend);
gotAnswer = (TextView) findViewById(R.id.tvGot);
start.setOnClickListener(this);
startFor.setOnClickListener(this);
}
#Override
public void onClick(View view) {
switch (view.getId()){
case R.id.bSA:
String bread = sendET.getText().toString();
Bundle basket = new Bundle();
basket.putString("key", bread);
Intent a = new Intent(getApplicationContext(), OpenedClass.class);
a.putExtras(a);
startActivity(a);
break;
case R.id.bSAFR:
break;
}
}
}
get.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">
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/etSend" android:layout_gravity="center_horizontal"/>
<Button
android:layout_below="#+id/etSend"
android:layout_alignParentRight="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Start Activity"
android:id="#+id/bSA"/>
<Button
android:layout_toLeftOf="#+id/bSA"
android:layout_alignTop="#+id/bSA"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Start Activity for Results"
android:id="#+id/bSAFR"/>
<TextView
android:layout_below="#+id/bSAFR"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="TextView"
android:id="#+id/tvGot"/>
</RelativeLayout>
=============================================================
OpenedClass.java
package com.example.myapp;
import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.RadioGroup;
import android.widget.TextView;
public class OpenedClass extends Activity implements View.OnClickListener, RadioGroup.OnCheckedChangeListener {
TextView question, test;
Button returnData;
RadioGroup selectionList;
String gotBread;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.send);
initialize();
Bundle gotBasket = getIntent().getExtras();
gotBread = gotBasket.getString("key");
question.setText(gotBread);
}
private void initialize() {
question = (TextView) findViewById(R.id.tvQuestion);
test = (TextView) findViewById(R.id.tvText);
returnData = (Button) findViewById(R.id.bReturn);
returnData.setOnClickListener(this);
selectionList = (RadioGroup) findViewById(R.id.rgAnswers);
selectionList.setOnCheckedChangeListener(this);
}
#Override
public void onClick(View view) {
}
#Override
public void onCheckedChanged(RadioGroup arg0, int arg1) {
// TODO Auto-generated method stub
switch (arg1) {
case R.id.rCrazy:
break;
case R.id.rFun:
break;
case R.id.rBoth:
break;
}
}
}
send.xml
<?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">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceSmall"
android:text="Hosein is ..."
android:id="#+id/tvQuestion"/>
<RadioGroup
android:id="#+id/rgAnswers"
android:layout_width="wrap_content"
android:layout_height="wrap_content">
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Crazy"
android:id="#+id/rCrazy"
/>
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Super Fun"
android:id="#+id/rFun"/>
<RadioButton
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Both"
android:id="#+id/rBoth"/>
</RadioGroup>
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="Return"
android:id="#+id/bReturn"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="New Text"
android:id="#+id/tvText"/>
</LinearLayout>
Intent a = new Intent(getApplicationContext(), OpenedClass.class);
a.putExtras(a);
You cannot put a inside itself. This causes infinite recursion and stack overflow.
You probably wanted
a.putExtras(basket);