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web app gives out blank screen on installing and opening?

I'm a rookie at android, trying to make webapp, by following a tutorial.
However, when installed a signed apk, after opening it gives a blank page. have no idea what went wrong.
My edited pages are:
Activity_main:
<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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="fill_parent"
android:layout_height="fill_parent"
android:paddingBottom="1dp"
android:paddingLeft="1dp"
android:paddingRight="1dp"
tools:context=".MainActivity">
<ProgressBar
style="?android:attr/progressBarStyleLarge"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="#+id/progressBar"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true" />
<android.support.v4.widget.SwipeRefreshLayout
android:id="#+id/swipe"
android:layout_width="match_parent"
android:layout_height="match_parent">
<WebView
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="#+id/webView"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_alignParentTop="true" />
</android.support.v4.widget.SwipeRefreshLayout>
</android.support.constraint.ConstraintLayout>
Android Manifest:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.iinfohub.www.iinfohub">
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE"></uses-permission>
<application
android:allowBackup="true"
android:icon="#drawable/logo"
android:label="IINFO HUB"
android:roundIcon="#drawable/logo"
android:supportsRtl="true"
android:theme="#style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
MainActivity.java
package com.iinfohub.www.iinfohub;
import android.content.Intent;
import android.net.Uri;
import android.support.v4.widget.SwipeRefreshLayout;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.KeyEvent;
import android.webkit.WebView;
import android.webkit.WebViewClient;
public class MainActivity extends AppCompatActivity {
WebView mWebView;
SwipeRefreshLayout swipe;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
swipe = (SwipeRefreshLayout) findViewById(R.id.swipe);
swipe.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
public void onRefresh() {
LoadWeb();
}
});
LoadWeb();
}
public void LoadWeb() {
mWebView = (WebView) findViewById(R.id.webView);
mWebView.getSettings().setJavaScriptEnabled(true);
mWebView.getSettings().setAppCacheEnabled(true);
mWebView.loadUrl("http://iinfohub.com/forapp/index.php");
swipe.setRefreshing(true);
mWebView.setWebViewClient(new WebViewClient() {
public void onReveivedError(WebView view, int errorCode, String description, String failingUrl) {
mWebView.loadUrl("file://android_asset/error.html");
}
public void onPageFinished(WebView view, String url) {
//hide the swipe refreshlayout
swipe.setRefreshing(false);
}
});
}
#Override
public boolean onKeyDown(final int keyCode, final KeyEvent event) {
if ((keyCode == KeyEvent.KEYCODE_BACK) && mWebView.canGoBack()) {
mWebView.goBack();
return true;
}
return super.onKeyDown(keyCode, event);
}
}
All i did was follow that tutorial, as i mentioned, it gives a blank page on running the signed APK.
Any help on this is greatly appreciated.

I think you should loadUrl after all.
because settings/configs must apply before loading page.

Why my xml code appear in xml layout file bu not in android device?

I have imported some code in android studio. The XML codes appear in the XML file resource but not in android device. My Main Activity is set in default and have no error.
<?xml version="1.0" encoding="utf-8"?
<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:background="#color/tan_background"
android:orientation="vertical" tools:context="com.example.android.miwok.MainActivity"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://schemas.android.com/apk/res/android ">
<TextView android:id="#+id/numbers"
style="#style/CategoryStyle"
android:background="#color/category_numbers"
android:text="#string/category_numbers"
android:onClick="openNumbersList"/>
<TextView android:id="#+id/family"
style="#style/CategoryStyle"
android:background="#color/category_family"
android:text="#string/category_family" />
<TextView android:id="#+id/colors"
style="#style/CategoryStyle"
android:background="#color/category_colors"
android:text="#string/category_colors" />
<TextView android:id="#+id/phrases"
style="#style/CategoryStyle"
android:background="#color/category_phrases"
android:text="#string/category_phrases" />
</LinearLayout>
And this is my Main Activity:
package com.example.android.miwok;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void openNumbersList(View view){
Intent intent = new Intent(this,NumbersActivity.class);
startActivity(intent);
}
}

You say your MainActivity is set in DEFAULT. If that is referring to your manifest, please change it to this:
<activity
android:name="com.example.android.miwok.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>
You need a LAUNCHER activity in order for Android to know which Activity to launch when the app starts.

Set your xml file in your Activity as shown below:
#Override
protected void onCreate(Bundle savedInstanceState)
{
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
and set the TextView text color to black
android:textColor="#000"

Why placing a call programatically gives error message "Internet Calling not Supported"?

This is my code:
public String a_number;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_make_the_call);
//
callButton = (ImageButton)findViewById(R.id.call_button);
aCall = (TextView)findViewById(R.id.number_a);
a_number = aCall.getText().toString();
}
public void makeCallFunction(View view) {
String temp = "";
temp = "tel:"+a_number;
Intent callIntent = new Intent(Intent.ACTION_CALL);
callIntent.setData(Uri.parse(temp));
startActivity(callIntent);
}
My XML file contains:
<ImageButton
android:id="#+id/call_button"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentEnd="true"
android:layout_alignParentRight="true"
android:src="#drawable/dial"
android:onClick="makeCallFunction"/>
I have added the following in my manifest file:
<uses-permission android:name="android.permission.CALL_PHONE"/>
I searched my best for answers but found nothing helpful..
EDIT:
When I give a value directly, the call gets placed now.
Eg:
callIntent.setData(Uri.parse("tel:9876543210"));
But the problem remains when I read the number from my text view and try to place call with that number.
Can someone help me out?
Thanks in advance
If there's some alternate way to implement call, that'd help too.

Disable SIP Internet Calling and VoIP on your emulator or debugging device. This is the steps for Samsung Galaxy S4 :
go to settings > call > disable internet calling(in bottom)
I don't know what you are doing wrong, but see for yourself a working example :
MakeTheCallActivity.java
package com.example.makethecall;
import android.content.Intent;
import android.net.Uri;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
public class MakeTheCallActivity extends ActionBarActivity {
private EditText mEditText;
private Button mButton;
private final String TAG = "MakeTheCallActivity";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_make_the_call);
mButton = (Button)findViewById(R.id.call_button);
mButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
mEditText = (EditText)findViewById(R.id.phone_number);
String phoneNumber = mEditText.getText().toString();
Log.d(TAG, phoneNumber);
Intent intent = new Intent(Intent.ACTION_CALL, Uri.parse("tel:" + phoneNumber));
startActivity(intent);
}
});
}
}
activity_make_the_call.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" tools:context=".MakeTheCallActivity"
android:orientation="vertical">
<EditText
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/phone_number" />
<Button
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="call"
android:id="#+id/call_button" />
</LinearLayout>
AndroidManifest.xml
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.sauravsamamt.makethecall" >
<uses-permission android:name="android.permission.CALL_PHONE" />
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MakeTheCallActivity"
android:label="#string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
You can see I'm not using a hardcoded number. Make sure you enter a valid number. That's it.

My app stops working

I am writing a basic application which contains two activities. Both contain a TextView showing the title and the first one contains an EditText in which the user types a message and clicks on a button on its side, the second activity is launched which shows the message the user types.
It has the following problem:
1.When I click on the button, the app stops saying "Unfortunately Write n Display and stopped.", rather than launching the second activity at all.
The Logcat can be found here: enter link description here since adding it to the question exceeded the limit.
CODE OF FIRST ACTIVITY: -
package com.practice.myfirstapp1;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.EditText;
//import android.view.Menu;
public class MainActivity extends Activity {
public static final String key_name="com.practice.firstApp.key";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void sendMessage(View view){
Intent intent= new Intent(this, SecondActivity.class);
EditText editText=(EditText) findViewById(R.id.EditText1_MainActivity);
String key_value= editText.getText().toString();
intent.putExtra(key_name, key_value);
startActivity(intent);
}
}
LAYOUT OF FIRST ACTIVITY: -
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent"
tools:context=".MainActivity" >
<TextView
android:id="#+id/TextView1_MainActivity"
android:layout_alignParentTop="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_centerHorizontal="true"
android:text="#string/title_MainActivity"
android:textStyle="bold"/>
<EditText
android:id="#+id/EditText1_MainActivity"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#+id/TextView1_MainActivity"
android:hint="#string/EditText_MainActivity"
android:textStyle="italic" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="#id/TextView1_MainActivity"
android:layout_toRightOf="#id/EditText1_MainActivity"
android:text="#string/Button_MainActivity"
android:onClick="sendMessage"/>
</RelativeLayout>
CODE OF SECOND ACTIVITY: -
package com.practice.myfirstapp1;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.widget.TextView;
class SecondActivity extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState){
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_second);
Intent intent= getIntent();
String intent_value= intent.getStringExtra(MainActivity.key_name);
TextView textView= new TextView(this);
textView= (TextView) findViewById(R.id.TextView2_SecondActivity);
textView.setText(intent_value);
}
}
LAYOUT OF SECOND ACTIVITY: -
<?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:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="horizontal"
tools:context=".SecondActivity">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:text="#string/title_SecondActivity"
android:textStyle="bold"/>
<TextView
android:id="#+id/TextView2_SecondActivity"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />
</RelativeLayout>
STRINGS RESOURCE FILE:-
<?xml version="1.0" encoding="utf-8"?>
<resources>
<string name="app_name">Write n Display</string>
<string name="action_settings">Settings</string>
<string name="title_MainActivity">WRITE</string>
<string name="EditText_MainActivity">Your Message here</string>
<string name="Button_MainActivity">Send</string>
<string name="title_SecondActivity">DISPLAY</string>
</resources>
ANDROID MANIFEST FILE: -
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.practice.myfirstapp1"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="18" />
<application
android:allowBackup="true"
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme"
android:debuggable="true" >
<activity
android:name="com.practice.myfirstapp1.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.practive.myfirstapp1.SecondActivity"
android:label="#string/app_name">
</activity>
</application>
</manifest>

To solve your first issue: put below code to your textview of both xml files.
Reason: You had not put the android:layout_centerHorizontal="true" in your TextView
android:layout_alignParentTop="true"
android:layout_centerHorizontal="true"
android:text="#string/title_MainActivity"
To solve your second issue:Change LAYOUT OF FIRST ACTIVITY:
Reason: android:layout_width is "0dp". it should be wrap_content or fill_parent or match_parent
<EditText
android:id="#+id/EditText1_MainActivity"
android:layout_width="0dp"
android:layout_height="wrap_content"
android:layout_below="#+id/TextView1_MainActivity"
android:hint="#string/EditText_MainActivity"
android:textStyle="italic" />
To:
<EditText
android:id="#+id/EditText1_MainActivity"
android:layout_width="wrap_content" //you can put, fill_parent or match_parent
android:layout_height="wrap_content"
android:layout_below="#+id/TextView1_MainActivity"
android:hint="#string/EditText_MainActivity"
android:textStyle="italic" />
To solve your third issue: change your CODE OF FIRST ACTIVITY: -
Reason: You had put editText=(EditText) findViewById(R.id.EditText1_MainActivity); in sendMessage(View view). send message contains a View so whenever you initiate any component in this method, it will search that component on this particular view which is incorrect. you can initiate your components in any method which does not contain any view parameter.if you want to initiate any component in particular view then you have to initiate it like editText=(EditText)view.findViewById(R.id.EditText1_MainActivity);. But in your case edittext is in main view so you need to remove it from sendMessage(View view).
public class MainActivity extends Activity {
public static final String key_name="com.practice.firstApp.key";
EditText editText;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
editText=(EditText) findViewById(R.id.EditText1_MainActivity);
}
public void sendMessage(View view){
Intent intent= new Intent(this, SecondActivity.class);
String key_value= editText.getText().toString();
intent.putExtra(key_name, key_value);
startActivity(intent);
}
}
Change your second Activity
Reason: TextView textView= new TextView(this); is not correct way to initialize any component of your xml view.
TextView textView= new TextView(this);
textView= (TextView) findViewById(R.id.TextView2_SecondActivity);
textView.setText(intent_value);
To:
TextView textView;
textView= (TextView) findViewById(R.id.TextView2_SecondActivity);
textView.setText(intent_value);

you can solve your problem like this
1.replace
android:gravity="center_horizontal" by android:layout_gravity="center_horizontal".
2.Give layout_width as wrap_content for edittext of first activity xml
3.Make your sendMessage method public not private
To get the logcat In Eclipse, Goto Window-> Show View -> Other -> Android-> Logcat.
OR
Write LogCat in Quick Access edit box in your eclipse window (top right corner, just before Open Prospective button). And just select LogCat it will open-up the LogCat window in your current prospec

change private void sendMessage(View view) to public void sendMessage(View view) (private to public)
LAYOUT OF FIRST ACTIVITY:
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:orientation="horizontal"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:gravity="center_vertical" >
<TextView
android:id="#+id/TextView1_MainActivity"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#+string/title_MainActivity"
android:textStyle="bold"/>
<EditText
android:id="#+id/EditText1_MainActivity"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:hint="#string/EditText_MainActivity"
android:textStyle="italic" />
<Button
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/Button_MainActivity"
android:onClick="sendMessage"/>
LAYOUT OF SECOND ACTIVITY: -
<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:orientation="horizontal"
android:gravity="center_vertical"
tools:context=".SecondActivity">
<TextView
android:layout_alignParentTop="true"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#+string/title_SecondActivity"
android:textStyle="bold"/>
<TextView
android:id="#+id/TextView2_SecondActivity"
android:layout_width="wrap_content"
android:layout_height="wrap_content" />

Logcat shows the following:
Caused by: android.content.ActivityNotFoundException: Unable to find
explicit activity class
{com.practice.myfirstapp1/com.practice.myfirstapp1.SecondActivity};
have you declared this activity in your AndroidManifest.xml?
You did define SecondActivity in manifest, but the package name is wrong ( android:name="com.practive.myfirstapp1.SecondActivity" should be ndroid:name="com.practice.myfirstapp1.SecondActivity"
).
<activity
android:name="com.practice.myfirstapp1.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.practive.myfirstapp1.SecondActivity"
android:label="#string/app_name">
</activity>
It should be
<activity
android:name="com.practice.myfirstapp1.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.practice.myfirstapp1.SecondActivity"
android:label="#string/app_name">
</activity>

Application stops unexpectedly - Android

I am new to android development. After setting up an android project, I tried to get text input and passe it to another activity (screen).
When I run the project I don't get an error but when I click the application it shows the first screen then when click the button in the screen it gives the error 'application stopped unexpectedly'.
When I try the code without passing data from first screen to second screen , the application works properly.
This is MainActivity.java file:
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.EditText;
public class MainActivity extends Activity {
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final EditText et= (EditText) findViewById(R.id.editText1);
Button b = (Button)findViewById(R.id.button1);
b.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
//intent class is used for activating another or component or an activity
Intent intent =new Intent(MainActivity.this, Second.class);
intent.putExtra("textval", et.getText().toString());
startActivity(intent);
}
});}}
Here is the code for Second.java file:
import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;
public class Second extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
TextView tv= (TextView) findViewById(R.id.textView1);
tv.setText(getIntent().getExtras().getString("textval"));
}
}
Here is the activitymain.xml code:
<?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:layout_width="match_parent"
android:layout_height="match_parent">
<EditText android:id="#+id/editText1" android:layout_width="wrap_content"
android:layout_height="wrap_content" android:layout_alignParentLeft="true"
android:layout_alignParentRight="true" android:layout_alignParentTop="true"
android:ems="10"
android:inputType="text"
>
<requestFocus />
</EditText>
<Button android:id="#+id/button1" android:layout_width="wrap_content"
android:layout_height="wrap_content" android:layout_alignParentLeft="true"
android:layout_below="#+id/editText1" android:layout_marginTop="28dp"
android:text="#string/button" />
</RelativeLayout>
Here is the second xml file:
<?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">
<TextView android:id="#+id/textView1" android:layout_width="wrap_content"
android:layout_height="wrap_content" android:text="#string/textview" />
</LinearLayout>
Please help me to find the error. Since I don't get an error notification I am not able to proceed.
Thanks in advance...

This is what you missed on your Second.java:
setContentView(R.layout.second);
put it above of your textview declaration.

In your Second java file make changes as follows
import android.app.Activity;
import android.os.Bundle;
import android.widget.TextView;
public class Second extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.second);
TextView tv= (TextView) findViewById(R.id.textView1);
tv.setText(getIntent().getExtras().getString("textval"));
}
}

Declare Second Activity in android manifest file .
<activity android:name=".Second"/>
Add setContentView(R.layout.second); in second activity.

Add entry for second activity in your Manifest file.
Put first activity as a Launcher and other as a Default.
Here I have two activity MainActivity and Player.
First I Launches MainActivity and then call other activity Player
Note- Activity name should be same as class name, so Keep same in Manifest file as well.
Also you need to specify the layout file for both activity by setContentView in onCreate function.
Here is sample code-
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.vt.soc"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="8"
android:targetSdkVersion="15" />
<application
android:icon="#drawable/ic_launcher"
android:label="#string/app_name"
android:theme="#style/AppTheme" >
<activity
android:name=".MainActivity"
android:label="#string/title_activity_main" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".Player"
android:label="#string/title_activity_main" >
<intent-filter>
<action android:name="com.vt.soc.PALYER" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
</application>
</manifest>

- In your Second Activity you forgot to add the setContentView().
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.second);
TextView tv= (TextView) findViewById(R.id.textView1);
tv.setText(getIntent().getExtras().getString("textval"));
}
- Please also do see that you have added this Second Activity in your Manifest.xml file.