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Android - Store variable and use in webview link

I'm trying to store the users input from a text field in shared preferences and use that input in a webview link.
Here's what I have so far;
LoginActivity.java
package com.example.app;
import android.app.Activity;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.content.Intent;
public class LoginActivity extends Activity {
EditText subdomain;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_login);
subdomain = (EditText) findViewById(R.id.subdomain);
Button btn=(Button)findViewById(R.id.sign_in_button);
btn.setOnClickListener(new View.OnClickListener()
{
public void onClick(View v)
{
Intent myIntent = new Intent(LoginActivity.this,
MainActivity.class);
LoginActivity.this.startActivity(myIntent);
}
});
}
public void saveInfo (View view) {
SharedPreferences sharedPref = getSharedPreferences("spfile",
Activity.MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putString("name", YourSchool.getText().toString());
editor.commit();
}
}
MainActivity.java
package com.example.app;
import android.app.Activity;
import android.content.Context;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.webkit.WebSettings;
import android.webkit.WebView;
import android.webkit.WebViewClient;
public class MainActivity extends Activity {
private WebView mWebView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mWebView = (WebView) findViewById(R.id.activity_main_webview);
// Force links and redirects to open in the WebView instead of in a
browser
mWebView.setWebViewClient(new WebViewClient());
// Enable Javascript
WebSettings webSettings = mWebView.getSettings();
webSettings.setJavaScriptEnabled(true);
// Use remote resource
mWebView.loadUrl("https://"+client_subdomain+".domain.co.uk/texts");
// Stop local links and redirects from opening in browser instead
of WebView
mWebView.setWebViewClient(new MyAppWebViewClient());
}
public void displayData (View view) {
SharedPreferences sharedPref = getSharedPreferences("spfile",
Activity.MODE_PRIVATE);
String client_subdomain = sharedPref.getString("name", "");
}
// Prevent the back-button from closing the app
#Override
public void onBackPressed() {
if(mWebView.canGoBack()) {
mWebView.goBack();
} else {
super.onBackPressed();
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is
present.
getMenuInflater().inflate(R.menu.menu_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
activity_login.xml
<LinearLayout
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:gravity="center_horizontal"
android:orientation="vertical"
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.app.LoginActivity">
<LinearLayout
android:id="#+id/email_login_form"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="vertical">
<EditText
android:id="#+id/YourSchool"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:hint="Your school"
android:maxLines="1"
android:singleLine="true" />
<Button
android:id="#+id/sign_in_button"
style="?android:textAppearanceSmall"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginTop="16dp"
android:onClick="webView"
android:text="SIGN IN"
android:textStyle="bold" />
</LinearLayout>
</ScrollView>
</LinearLayout>
activity_main.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"
tools:context=".MainActivity">
<WebView
android:id="#+id/activity_main_webview"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</RelativeLayout>
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.app">
<uses-permission android:name="android.permission.INTERNET" />
<!-- To auto-complete the email text field in the login form with the
user's emails -->
<uses-permission android:name="android.permission.GET_ACCOUNTS" />
<uses-permission android:name="android.permission.READ_PROFILE" />
<uses-permission android:name="android.permission.READ_CONTACTS" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#android:style/Theme.NoTitleBar.Fullscreen">
<activity
android:name=".MainActivity"
android:label="#string/app_name"></activity>
<activity
android:name=".LoginActivity"
android:label="#string/title_activity_login">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER"
/>
</intent-filter>
</activity>
</application>
</manifest>
My problem is that the client_subdomain is flagged as red in the MainActivity.java and when I try to build the project, I get the error: cannot find symbol variable client_subdomain
I think it's probably something small that I've missed out but any help would be greatly appreciated.
Many thanks,
Sam

Store the variable using sharedPrefeence as below,
SharedPreferences sp = getSharedPreferences("your_prefs", Activity.MODE_PRIVATE);
SharedPreferences.Editor editor = sp.edit();
editor.putString("your_string_key", yourStringValue);
editor.commit();
Then retrieve the value as,
SharedPreferences sp = getSharedPreferences("your_prefs", Activity.MODE_PRIVATE);
String myStringValue = sp.getInt("your_string_key", -1);
Use the variable in the loadUrl as
mWebView.loadUrl("https://"+myStringValue+".mydomain.co.uk");

How do i get a button to open a new activity in android studio?

I'd seen this asked in many, many places and have tried to follow the instructions given to no avail. I dont know if the questions are old, i'm doing things incorrectly or if my android studio program isnt working. What i want to do is to only open a new activity when a button is clicked. I'm very new to developing android applications.
I've recently tried to follow the answer provided here: How do I get a button to open another activity in Android Studio?
OnClick on the button is called "goTutorials"
My original activity is called home (Not mainActivity)
The new one is called tutorials.
This is what i added from trying to follow the link above:
In home's java file:
btn = (Button)findViewById(R.id.open_activity_button);
btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
startActivity(new Intent(home.this, tutorials.class));
}
});
In manifest file:
<activity
android:name="tutorials"
android:label="#string/app_name">
</activity>

Method 1
Use the onclick attribute in XML (so that whenever you click the button, defined method will trigger)
Step 1. - go to the XML where you button is(activity_home) & add
<Button
............
android:onClick="gotoTutorial"/>
Step 2. - then go to the home.Java & add following
public void gotoTutorial(View v){
Intent tutorialPage = new Intent (this, tutorials.class);
startActivity(tutorialPage);
}
Method 2
Use the setOnClickListener
Step 1. -
//create the link to the button in the interface
btn_tutorial = (Button)findViewById(R.id.tutorial_button);
btn_tutorial.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent tutorialPage = new Intent (this, tutorials.class);
startActivity(tutorialPage);
}
}

I have created a sample app please see the code below.
You need to specify information of all activities in Manifest file.
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.nextech.startnewactivity">
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity
android:name=".MainActivity"
android:label="#string/app_name"
android:theme="#style/AppTheme.NoActionBar">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".TutorialsActivity"
android:label="#string/title_activity_tutorials"
android:theme="#style/AppTheme.NoActionBar"></activity>
</application>
</manifest>
My Launcher activity is MainActivity.java
package com.nextech.startnewactivity;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Button;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button startTutorials = (Button)findViewById(R.id.startTutorials);
startTutorials.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent tutorialsActivityIntent = new Intent(MainActivity.this,TutorialsActivity.class);
MainActivity.this.startActivity(tutorialsActivityIntent);
}
});
}
#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_main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
activity_main.xml
<?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: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"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:context="com.nextech.startnewactivity.MainActivity"
tools:showIn="#layout/activity_main">
<TextView android:id="#+id/welcomeText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="20dp"
android:layout_centerHorizontal="true"
android:text="Hello World! This is main activity!" />
<Button android:id="#+id/startTutorials"
android:layout_below="#+id/welcomeText"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:text="Start Tutorials"/>
</RelativeLayout>
TutorialsActivity.java
package com.nextech.startnewactivity;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
public class TutorialsActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_tutorials);
}
}
activity_tutorials.xml
<?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: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"
app:layout_behavior="#string/appbar_scrolling_view_behavior"
tools:context="com.nextech.startnewactivity.TutorialsActivity"
tools:showIn="#layout/activity_tutorials">
<TextView android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="This is tutorial activity"
android:layout_centerInParent="true"/>
</RelativeLayout>
I hope it helps.

Your manifest file is not displaying, but make sure you add the activity in your manifest AndroidManifest.xml in the application field. Here's an example from Google: Link
<application ... >
...
<activity
android:name="com.mycompany.myfirstapp.DisplayMessageActivity"
android:label="#string/title_activity_display_message"
android:parentActivityName="com.mycompany.myfirstapp.MyActivity" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.mycompany.myfirstapp.MyActivity" />
</activity>
Otherwise, the method you're using should be correct. You create an intent to the class of the Activity you want to start.
Intent intent = new Intent(this, tutorials.class);
startActivity(intent);
Make sure you have the necessary methods such as onCreate(Bundle savedInstance) Overrided.
Note that in the sample above android:name="" is your activity's full path name to the class (without .class/.java) and label is going to be the action toolbar string you'll see. In the <meta-data/> section you can alter the android:value="" to the starting activity's name so that will need to change based on what you call it.
Finally, make sure it has an XML view to go with it, as it gets inflated in the onCreate(Bundle savedInstance) call.
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_layout_here);
}

inside your activity file write this
Button btn = (Button)findViewById(R.id.open_activity_button);
btn.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
startActivity(new Intent(home.this, tutorials.class));
}
});

XML
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/button_send"
android:onClick="sendMessage" />
.Java class
/** Called when the user clicks the Send button */
public void sendMessage(View view) {
Intent intent = new Intent(this, YourActivityYouWantToOpen.class);
startActivity(intent);
}

Adding more buttons

I'm working on a app. Past days i'm trying to get more then one button to work on my page. But i can't figur it out. Can some one help? I'm new to Development :)
Layout (xml)
Activity_main
<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: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.rust.rustapp.MainActivity" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/hello_world" />
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:layout_centerVertical="true"
android:text="Button"
android:onClick="button1Click"/>
<Button
android:id="#+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="#+id/button1"
android:layout_below="#+id/button1"
android:layout_marginTop="38dp"
android:text="Button"
android:onClick="button1Click"
/>
</RelativeLayout>
Java:
MainActivty:
package com.rust.rustapp;
import android.support.v7.app.ActionBarActivity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
public class MainActivity extends ActionBarActivity {
Button button1;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
button1 = (Button)findViewById(R.id.button1);
button1.setOnClickListener(new View.OnClickListener() {
private void button1Click()
{
startActivity(new Intent(MainActivity.this, Intro.class));
}
#Override
public void onClick(View v) {
switch (v.getId())
{
case R.id.button1:
button1Click();
break;
}
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}
Intro.xml (Button1 is opening this page)
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:background="#drawable/test"
>
</LinearLayout>
Intro.java
package com.rust.rustapp;
import android.app.Activity;
import android.os.Bundle;
public class Intro extends Activity{
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.intro);
}
Manifest:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.rust.rustapp"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="21" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".Intro"
android:label="#string/app_name" >
</activity>
</application>
</manifest>
The new layout name is: FunPage
Thx!

From the code you pasted for MainActivity, it looks like you are mixing two different ways to handle button clicks.
If you can to register the click listener from your layout xml, the method corresponding to the onClick attribute needs to be public and not declared as a method inside your button1 listener.
An alternative is to listen to click events solely with your Java code. If you do this, then remove the onClick attribute from your layout XML for that button. There are many, many examples out there.
button1.setOnClickListener(new View.OnClickListener(){
public void onClick(View view){
//TODO -- In your case, start the "Intro" activity
}
}
It might help if you extract that method to start the Intro activity to a method outside of the click listener (i.e., as a method of MainActivity).

Is there something that needs to be added to avoid memory leaks when switching between activities?

I'm trying to figure out how to have multiple activities with my application. I have striped it down to the lowest element to make it easy to see what I'm doing and understand my question.
When the program runs it shows a screen (activity) that says “Multiple Activities Example (screen1). It has a “Button 1” to click to see the next activity.
Clicking the Button 1 will take you to a different activity screen that says “Multiple Activities Example (screen2). It has a button 2 that when pressed will go back to screen1.
I was trying to figure out some type of return method to go back to the previous screen, but couldn't figure out any.
So, my concern/question is, is there some type of memory leak where using this method is going deeper into layers that require some type of return?
The code is attached.
MainActivity:
package apollo.MultipleActivities;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
public class MainActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void button1_click(View v) {
Intent myIntent = new Intent(this, SecondActivity.class);
startActivity(myIntent);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
Second Activity:
package apollo.MultipleActivities;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
public class SecondActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.secondactivity);
}
public void button2_click(View v) {
Intent myIntent = new Intent(this, MainActivity.class);
startActivity(myIntent);
}
}
Main Activity XML Layout:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/screen1" />
<Button
android:id="#+id/button1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/button1" android:onClick="button1_click"/>
</LinearLayout>
Second Activity XML Layout:
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
<TextView
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:text="#string/screen2" />
<Button
android:id="#+id/button2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:onClick="button2_click"
android:text="#string/button2" />
</LinearLayout>
Manifest file:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="apollo.MultipleActivities"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="19" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="apollo.MultipleActivities.MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity android:name=".SecondActivity"></activity>
</application>
</manifest>
The app runs perfect and do exactly what I'm trying to have it do. My concern is about the integrity of the overall Android. If the program stays running and is used a lot, am I in for memory leak crashes down the road.
Thanks!

I was trying to figure out some type of return method to go back to the previous screen, but couldn't figure out any.
Option #1: Call finish() instead of startActivity() in SecondActivity. This will destroy the current activity and return control to the preceding activity, which in this case is MainActivity.
Option #2: Add FLAG_ACTIVITY_REORDER_TO_FRONT on the Intent you use to start MainActivity from SecondActivity to bring the existing instance of MainActivity to the top of the back stack. Pressing BACK from there would return you to SecondActivity, which may not be what you have in mind.

Android Tutorial issue

I am new to android, Eclipse and Java.
I started these tutorials from here: http://developer.android.com/training/basics/firstapp/index.html
I did all the steps from the link above...my problem is when I run this app and press the 'Send' button...nothing happens, there are no errors in my Console or LogCat.
Here is my code I ended up with:
activity_main.xml:
<LinearLayout 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:orientation="horizontal" >
<EditText android:id="#+id/edit_message"
android:layout_weight="1"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:hint="#string/edit_message" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/button_send"
android:onClick="sendMessage" />
</LinearLayout>
strings.xml:
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">MyFirstApp</string>
<string name="action_settings">Settings</string>
<string name="edit_message">Enter a message</string>
<string name="button_send">Send</string>
<string name="title_activity_main">MainActivity</string>
<string name="title_activity_display_message">My Message</string>
<string name="hello_world">Hello world!</string>
</resources>
MainActivity.java:
package com.example.myfirstapp;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.widget.EditText;
public class MainActivity extends Activity {
public final static String EXTRA_MESSAGE = "com.example.myfirstapp.MESSAGE";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
public void sendMessage(View view) {
Intent intent = new Intent(this, DisplayMessageActivity.class);
EditText editText = (EditText) findViewById(R.id.edit_message);
String message = editText.getText().toString();
intent.putExtra(EXTRA_MESSAGE, message);
}
}
DisplayMessageActivity.java:
package com.example.myfirstapp;
import android.annotation.SuppressLint;
import android.annotation.TargetApi;
import android.app.Activity;
import android.content.Intent;
import android.os.Build;
import android.os.Bundle;
import android.support.v4.app.NavUtils;
import android.view.MenuItem;
import android.widget.TextView;
public class DisplayMessageActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Get the message from the intent
Intent intent = getIntent();
String message = intent.getStringExtra(MainActivity.EXTRA_MESSAGE);
// Create the text view
TextView textView = new TextView(this);
textView.setTextSize(40);
textView.setText(message);
// Set the text view as the activity layout
setContentView(textView);
// Show the Up button in the action bar.
setupActionBar();
}
/**
* Set up the {#link android.app.ActionBar}, if the API is available.
*/
#SuppressLint("NewApi")
#TargetApi(Build.VERSION_CODES.HONEYCOMB)
private void setupActionBar() {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
getActionBar().setDisplayHomeAsUpEnabled(true);
}
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
// This ID represents the Home or Up button. In the case of this
// activity, the Up button is shown. Use NavUtils to allow users
// to navigate up one level in the application structure. For
// more details, see the Navigation pattern on Android Design:
//
// http://developer.android.com/design/patterns/navigation.html#up-vs-back
//
NavUtils.navigateUpFromSameTask(this);
return true;
}
return super.onOptionsItemSelected(item);
}
}
and activity_display_message.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: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=".DisplayMessageActivity" >
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/hello_world" />
</RelativeLayout>
Has anyone else ran into the same issue as me? Any help would be appreciated.
MyFirstApp Manifest:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.myfirstapp"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="17" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name="com.example.myfirstapp.MainActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="com.example.myfirstapp.DisplayMessageActivity"
android:label="#string/title_activity_display_message"
android:parentActivityName="com.example.myfirstapp.MainActivity" >
<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.example.myfirstapp.MainActivity" />
</activity>
</application>
</manifest>

You need to call startActivity
public void sendMessage(View view) {
Intent intent = new Intent(this, DisplayMessageActivity.class);
EditText editText = (EditText) findViewById(R.id.edit_message);
String message = editText.getText().toString();
intent.putExtra(EXTRA_MESSAGE, message);
startActivity(intent); // missing
}
Also make sure you have made an entry for the activities in manifest file.