Develop Reference

Problem with Audio in a basic music player in Android Studio

I created a basic music player app in Android Studio with the music file stored in the raw directory under resources and Mp3 format.
the issue is that though the toast inside the event listener gets displayed , the audio is not playing except once(i really do not know how).
the code is as below.
the manifest file
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.basicmusicplayer">
<uses-permission android:name="android.permission.INTERNET" />
<application
android:allowBackup="true"
android:icon="#mipmap/ic_launcher"
android:label="#string/app_name"
android:roundIcon="#mipmap/ic_launcher_round"
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>
the xml file
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.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="match_parent"
android:layout_height="match_parent"
android:layout_gravity="center"
tools:context=".MainActivity">
<TextView
android:id="#+id/textView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="#string/greetings"
android:textSize="30sp"
android:textStyle="bold"
app:layout_constraintLeft_toLeftOf="parent"
app:layout_constraintRight_toRightOf="parent"
app:layout_constraintTop_toTopOf="parent" />
<ImageView
android:id="#+id/imageView"
android:layout_width="221dp"
android:layout_height="298dp"
android:layout_marginStart="8dp"
android:layout_marginLeft="8dp"
android:layout_marginTop="104dp"
android:layout_marginEnd="8dp"
android:layout_marginRight="8dp"
app:layout_constraintEnd_toEndOf="parent"
app:layout_constraintHorizontal_bias="0.505"
app:layout_constraintStart_toStartOf="parent"
app:layout_constraintTop_toBottomOf="#+id/textView"
app:srcCompat="#android:drawable/ic_media_play" />
<Button
android:id="#+id/pause"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginLeft="8dp"
android:layout_marginTop="8dp"
android:layout_marginEnd="8dp"
android:layout_marginRight="8dp"
android:layout_marginBottom="8dp"
android:text="#string/pause"
app:layout_constraintBottom_toBottomOf="parent"
app:layout_constraintEnd_toStartOf="#+id/stop"
app:layout_constraintHorizontal_bias="0.565"
app:layout_constraintStart_toEndOf="#+id/play"
app:layout_constraintTop_toBottomOf="#+id/imageView"
app:layout_constraintVertical_bias="0.205" />
<Button
android:id="#+id/play"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="8dp"
android:layout_marginLeft="8dp"
android:text="#string/play"
app:layout_constraintBaseline_toBaselineOf="#+id/pause"
app:layout_constraintStart_toStartOf="parent" />
<Button
android:id="#+id/stop"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginEnd="8dp"
android:layout_marginRight="8dp"
android:text="#string/stop"
app:layout_constraintBaseline_toBaselineOf="#+id/pause"
app:layout_constraintEnd_toEndOf="parent" />
</androidx.constraintlayout.widget.ConstraintLayout>
the java code
package com.example.basicmusicplayer;
import androidx.appcompat.app.AppCompatActivity;
import android.app.Activity;
import android.content.Context;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
MediaPlayer player;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
/*
an object of class MediaPlayer created named player
a mp3 file is added to the object using create method*/
player = MediaPlayer.create(this, R.raw.adele);
// setting up inline event listeners to the button
// first comes the play button
Button play_music = findViewById(R.id.play);
play_music.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Toast.makeText(getApplicationContext(), "Playing sound",Toast.LENGTH_SHORT).show();
player.start();
}
});
// adding event listener on pause button
Button pause_music = findViewById(R.id.pause);
pause_music.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Toast.makeText(getApplicationContext(), "paused sound",Toast.LENGTH_SHORT).show();
player.pause();
}
});
// adding event listener for stop button
Button stop_music = findViewById(R.id.stop);
stop_music.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Toast.makeText(getApplicationContext(), "stopped sound",Toast.LENGTH_SHORT).show();
player.stop();
}
});
}
}

private MediaPlayer mp;
/** Called when the activity is first created. */
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
Button b = (Button) findViewById(R.id.button1);
final TextView t = (TextView) findViewById(R.id.textView1);
b.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
stopPlaying();
mp = MediaPlayer.create(PlayaudioActivity.this, R.raw.far);
mp.start();
}
});
}
private void stopPlaying() {
if (mp != null) {
mp.stop();
mp.release();
mp = null;
}
}

Android Studio: FATAL EXCEPTION: main while getting user inputs

I was trying to use user input name for later use but Once i run the app this is closed by saying unfortunately your app has stopped. I have provided Main activity,Layout xml and android manifest codes. Please anyone answer this . I am newbie in android and cant figure out the error.
Main_activity
package rupakthapa.droiddynasty.com.interactivestory2;
import android.content.Context;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import static android.R.attr.duration;
import static android.R.attr.name;
public class MainActivity extends AppCompatActivity {
private EditText mNameField;
private Button mButton;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
mNameField = (EditText) findViewById(R.id.nameField);
mButton = (Button) findViewById(R.id.startButton);
mButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String a= mNameField.getText().toString();
Context context = getApplicationContext();
int length = Toast.LENGTH_LONG;
Toast toast = Toast.makeText(context, a, length);
toast.show();
}
});
}
}
XML
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout
xmlns:app="http://schemas.android.com/apk/res-auto"
android:id="#+id/activity_main"
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="rupakthapa.droiddynasty.com.interactivestory2.MainActivity">
<ImageView
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:srcCompat="#mipmap/ic_launcher"
android:id="#+id/imageView"
android:adjustViewBounds="true"
android:scaleType="fitXY"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginBottom="149dp"
android:contentDescription="startImage"/>
<TextView
android:layout_width="match_parent"
android:id="#+id/nameField"
android:hint="Enter YOur Name"
android:layout_above="#+id/startButton"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginBottom="11dp"
android:maxLength="30"
android:layout_marginLeft="10dp"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:layout_height="wrap_content"
android:textSize="16sp"/>
<Button
android:text="Start your adventure"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:id="#+id/startButton"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"/>
</RelativeLayout>
Android Manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest package="rupakthapa.droiddynasty.com.interactivestory2"
xmlns:android="http://schemas.android.com/apk/res/android">
<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:screenOrientation="portrait">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
</application>
</manifest>

There is a problem here. You dont have EditText in your layout.
mNameField = (EditText) findViewById(R.id.nameField);
In your layout you should change TextView to EditText
<EditText
android:layout_width="match_parent"
android:id="#+id/nameField"
android:hint="Enter YOur Name"
android:layout_above="#+id/startButton"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_marginBottom="11dp"
android:maxLength="30"
android:layout_marginLeft="10dp"
android:layout_alignParentRight="true"
android:layout_alignParentEnd="true"
android:layout_height="wrap_content"
android:textSize="16sp"/>

Change Password Activity

I have a problem in this app, it show me "Unfortunately, app has stopped"
MainActivity.class
package ahmedchtn.stockmanager;
import android.content.Intent;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
public class MainActivity extends AppCompatActivity {
EditText username;
EditText password;
Button loginbutton;
Button bpasschange;
int counter = 3;
String username_string ;
String password1 = "";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
username = (EditText) findViewById(R.id.identifer);
password = (EditText) findViewById(R.id.password);
loginbutton = (Button) findViewById(R.id.bLogin);
bpasschange = (Button) findViewById(R.id.bCh);
username_string = "admin";
if (password1 == "") {
password1 = "admin";
} else {
Intent intent4 = getIntent();
password1 = intent4.getStringExtra("oldpassw");
}
bpasschange.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intentoldpass = new Intent(MainActivity.this, PasswordChange.class);
intentoldpass.putExtra("oldpassw", password1);
Intent intentpasschan = new Intent(getApplicationContext(), PasswordChange.class);
startActivity(intentpasschan);
}
});
loginbutton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
if (username.getText().toString().equals(username_string) &&
password.getText().toString().equals(password1)) {
Toast.makeText(getApplicationContext(),
"Redirecting...", Toast.LENGTH_SHORT).show();
Intent iop = new Intent(getApplicationContext(), ManagementPage.class);
startActivity(iop);
} else {
Toast.makeText(getApplicationContext(),
"Wrong Entries", Toast.LENGTH_SHORT).show();
counter--;
if (counter == 0) {
loginbutton.setEnabled(false);
}
}
}
}
);
}
}
PasswordChange.class
package ahmedchtn.stockmanager;
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;
public class PasswordChange extends AppCompatActivity {
Button bchange;
EditText oldpassword;
EditText newpassword;
String oldpass;
String newpass;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_password_change);
bchange = (Button) findViewById(R.id.bChange2);
oldpassword = (EditText) findViewById(R.id.old_password);
newpassword = (EditText) findViewById(R.id.new_password);
bchange.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent ioldpass = getIntent();
oldpass = ioldpass.getStringExtra("oldpassw");
if (oldpass == (oldpassword.getText().toString())) {
newpass = newpassword.getText().toString();
Intent intentnew = new Intent(PasswordChange.this, MainActivity.class);
intentnew.putExtra("passnew", newpass);
startActivity(intentnew);
Intent intent = new Intent(getApplicationContext(), MainActivity.class);
startActivity(intent);
}
}
});
}
}
I think that the problem is with the intents..
Thanks in advance for your help !
Is there any other solutions
The logcat
E/AndroidRuntime: FATAL EXCEPTION: main
java.lang.NullPointerException
at ahmedchtn.stockmanager.MainActivity$2.onClick(MainActivity.java:46)
at android.view.View.performClick(View.java:4439)
at android.widget.Button.performClick(Button.java:139)
at android.view.View$PerformClick.run(View.java:18395)
at android.os.Handler.handleCallback(Handler.java:725)
at android.os.Handler.dispatchMessage(Handler.java:92)
at android.os.Looper.loop(Looper.java:176)
at android.app.ActivityThread.main(ActivityThread.java:5317)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1102)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:869)
at dalvik.system.NativeStart.main(Native Method)
Application terminated.
Xml Codes
activity_main.xml
<?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:id="#+id/activity_main"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical"
android:paddingLeft="#dimen/activity_horizontal_margin"
android:paddingRight="#dimen/activity_horizontal_margin"
android:paddingTop="#dimen/activity_vertical_margin"
tools:context="ahmedchtn.stockmanager.MainActivity">
<EditText
android:id="#+id/identifer"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="#dimen/activity_vertical_margin"
android:hint="#string/enter_your_id" />
<EditText
android:id="#+id/password"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="#dimen/activity_vertical_margin"
android:hint="#string/enter_your_password"
android:inputType="textPassword" />
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:orientation="horizontal"
android:weightSum="1">
<Button
android:id="#+id/bLogin"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_weight="0.5"
android:text="#string/login" />
<Button
android:id="#+id/bCh"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="changer passe" />
</LinearLayout>
</LinearLayout>
activity_password_change.xml
<?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:id="#+id/activity_password_change"
android:layout_width="match_parent"
android:layout_height="match_parent"
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="ahmedchtn.stockmanager.PasswordChange">
<EditText
android:id="#+id/old_password"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="#dimen/activity_vertical_margin"
android:hint="#string/enter_your_old_password" />
<EditText
android:id="#+id/new_password"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_margin="#dimen/activity_vertical_margin"
android:hint="#string/enter_your_new_password" />
<LinearLayout
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_gravity="center"
android:layout_margin="#dimen/activity_vertical_margin"
android:weightSum="1">
<Button
android:id="#+id/bChange2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="#dimen/activity_vertical_margin"
android:layout_weight="0.5"
android:text="#string/confirm" />
<Button
android:id="#+id/main_page"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="#dimen/activity_vertical_margin"
android:layout_weight="0.5"
android:text="#string/main_page" />
</LinearLayout>
</LinearLayout>
Manifest
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="ahmedchtn.stockmanager">
<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">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name=".ManagementPage"
android:parentActivityName=".MainActivity" />
<activity android:name=".ProductsSearch" />
<activity android:name=".ProductsCommand" />
<activity
android:name=".Editor"
android:parentActivityName=".ProductsList" />
<activity android:name=".ProductsList" />
<provider
android:name=".data.ProductProvider"
android:authorities="ahmedchtn.stockmanager"
android:exported="false" />
<activity android:name=".PasswordChange"></activity>
</application>
</manifest>
I have updated my code

From the information you've provided so far (NPE on line 28 of PasswordChange.class), it looks like this line is causing the issue:
bchange = (Button) findViewById(R.id.bChange);
bchange.setOnClickListener(new View.OnClickListener() {
...
You have a button named bChange in both of your layout xml files - change one of them into something unique. I highly recommend that all components should be uniquely named through the app, as that stops the possibility of an activity accidentally referencing the wrong resource.
Example:
activity_password_change.xml
...
<Button
android:id="#+id/bPasswordChange"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_margin="#dimen/activity_vertical_margin"
android:layout_weight="0.5"
android:text="#string/confirm" />
...
PasswordChange.java
...
bchange = (Button) findViewById(R.id.bPasswordChange);
...
For the second issue that's arisen in MainActivity.java:
Intent intentbool = getIntent();
bmain = intentbool.getBooleanExtra("bool", bmain);
However, your problem here lies with line 20:
Boolean bmain;
Because you've declared a Boolean object rather than a boolean primitive (note the capital B), it is null by default as you've not initialised it. Change it to a primitive:
boolean bmain;

Make sure you have defined PasswordChange.class in your Manifest.xml file.
An example would be <activity android:name=".PasswordChange"/>. That's the most common reason for an app to crash when going to a new activity.

Too many output application using Android Studio?

Running the app cause no problem but it shows a warning
Too many Output!
Surprisingly when I check my phone because I use it as my deployment output instead of a virtual device, there are 3 application that was installed. Here's the screen shot.
phone screenshot
Here's my Java Codes
MainActivity.Java
package com.faacts.jayson.faactsv004;
import android.content.Intent;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
Button button;
button = (Button) findViewById(R.id.btnEnglish);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(getBaseContext(), Index.class);
startActivity(intent);
}
});
}
}
Splash.Java
package com.faacts.jayson.faactsv004;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.animation.Animation;
import android.view.animation.AnimationUtils;
import android.widget.ImageView;
/**
* Created by Jayson on 5/22/2016.
*/
public class Splash extends Activity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.splash);
final ImageView iv = (ImageView) findViewById(R.id.imageView);
final Animation an = AnimationUtils.loadAnimation(getBaseContext(), R.anim.rotate);
final Animation an2 = AnimationUtils.loadAnimation(getBaseContext(),R.anim.abc_fade_out);
iv.startAnimation(an);
an.setAnimationListener(new Animation.AnimationListener() {
#Override
public void onAnimationStart(Animation animation) {
}
#Override
public void onAnimationEnd(Animation animation) {
iv.startAnimation(an2);
finish();
Intent i = new Intent(getBaseContext(), MainActivity.class);
startActivity(i);
}
#Override
public void onAnimationRepeat(Animation animation) {
}
});
}
}
Index.Java
import android.text.method.HideReturnsTransformationMethod;
import android.text.method.PasswordTransformationMethod;
import android.view.View;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.CompoundButton.OnCheckedChangeListener;
import android.widget.EditText;
/**
* Created by Jayson on 5/22/2016.
*/
public class Index extends AppCompatActivity {
EditText txtpassword;
CheckBox chkbox;
#Override
protected void onCreate(Bundle saveInstanceState) {
super.onCreate(saveInstanceState);
setContentView(R.layout.index);
Button button;
button = (Button) findViewById(R.id.btnRegister);
button.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(getBaseContext(), Registration.class);
startActivity(intent);
}
});
txtpassword = (EditText) findViewById(R.id.txtPassword);
chkbox = (CheckBox) findViewById(R.id.chkBox);
chkbox.setOnCheckedChangeListener(new OnCheckedChangeListener() {
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
// checkbox status is changed from uncheck to checked.
if (!isChecked) {
// show password
txtpassword.setTransformationMethod(PasswordTransformationMethod.getInstance());
chkbox.setText("Reveal Password");
} else {
// hide password
txtpassword.setTransformationMethod(HideReturnsTransformationMethod.getInstance());
chkbox.setText("Hide Password");
}
}
});
}
}
Registration.Java
package com.faacts.jayson.faactsv004;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.app.Activity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Spinner;
import android.widget.AdapterView.OnItemSelectedListener;
/**
* Created by Jayson on 5/22/2016.
*/
public class Registration extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.registration);
Spinner staticSpinner = (Spinner) findViewById(R.id.static_spinner);
// Create an ArrayAdapter using the string array and a default spinner
ArrayAdapter<CharSequence> staticAdapter = ArrayAdapter
.createFromResource(this, R.array.gender_array,
android.R.layout.simple_spinner_item);
// Specify the layout to use when the list of choices appears
staticAdapter
.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
// Apply the adapter to the spinner
staticSpinner.setAdapter(staticAdapter);
}
}
This is the example of my xml
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: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=".MainActivity"
android:background="#33ccff"
android:clickable="false"
style="#style/AppTheme">
<ImageView
android:layout_width="600dp"
android:layout_height="700dp"
android:id="#+id/imageView3"
android:src="#drawable/welcomepage"
android:layout_marginBottom="200dp"
android:layout_alignParentBottom="true"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:contentDescription="#string/welcomepage"/>
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:textAppearance="?android:attr/textAppearanceLarge"
android:text="Choose your language:"
android:id="#+id/textView"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="165dp"
android:textColor="#003333"
android:textStyle="bold" />
<Button
android:layout_width="180dp"
android:layout_height="wrap_content"
android:text="#string/btnFilipino"
android:id="#+id/btnFilipino"
android:layout_alignTop="#+id/textView"
android:layout_centerHorizontal="true"
android:layout_marginTop="40dp"
android:background="#drawable/bkg"
android:textColor="#000066"
android:textSize="25sp"
android:textStyle="bold" />
<Button
android:layout_width="180dp"
android:layout_height="wrap_content"
android:text="#string/btnEnglish"
android:id="#+id/btnEnglish"
android:background="#drawable/bkg"
android:layout_alignParentBottom="true"
android:layout_centerHorizontal="true"
android:layout_marginBottom="40dp"
android:textColor="#000066"
android:textSize="25sp"
android:textStyle="bold" />
</RelativeLayout>
index.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: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=".Index"
android:background="#33ccff"
android:clickable="false"
style="#style/AppTheme">
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#33ccff">
<ImageView
android:layout_width="380dp"
android:layout_height="90dp"
android:layout_marginTop="50dp"
android:id="#+id/imgULogo"
android:layout_gravity="center_horizontal"
android:src="#drawable/upperlogo2"
android:contentDescription="#string/upperlogo" />
<EditText
android:layout_width="318dp"
android:layout_height="40dp"
android:layout_marginTop="40dp"
android:layout_gravity="center_horizontal"
android:id="#+id/txtUsername"
android:background="#ffffff"
android:hint="#string/username"
android:textColorHint="#color/dim_foreground_material_dark"
android:textColor="#000000"
android:inputType="text" />
<EditText
android:layout_width="318dp"
android:layout_height="40dp"
android:layout_marginTop="30dp"
android:layout_gravity="center_horizontal"
android:inputType="textPassword"
android:ems="10"
android:id="#+id/txtPassword"
android:background="#ffffff"
android:hint="#string/password"
android:textColorHint="#color/dim_foreground_material_dark"
android:textColor="#000000" />
<CheckBox
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_marginStart="26dp"
android:layout_marginLeft="26dp"
android:text="#string/reveal_password"
android:id="#+id/chkBox" />
<Button
android:layout_width="180dp"
android:layout_height="wrap_content"
android:text="#string/login"
android:id="#+id/btnLogin"
android:layout_marginTop="90dp"
android:background="#drawable/bkg"
android:textColor="#000066"
android:textSize="25sp"
android:textStyle="bold"
android:layout_gravity="center_horizontal" />
<Button
android:layout_width="180dp"
android:layout_height="wrap_content"
android:text="#string/register"
android:id="#+id/btnRegister"
android:background="#drawable/bkg"
android:layout_marginTop="10dp"
android:textColor="#000066"
android:textSize="25sp"
android:textStyle="bold"
android:layout_gravity="center_horizontal" />
</LinearLayout>
</RelativeLayout>
Please hoping for your feedback Anyway, I am new in android studio.
Anyway, there are two xmls that I did not post I just only pasted the example two those are the registration.xml and splash.xml.
PROBLEM SOLVED: I put a android.intent.category.LAUNCHER instead of just a DEFAULT in every Java class on manifest declaration.
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.faacts.jayson.faactsv004">
<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">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
<activity android:name=".Splash">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
<activity android:name=".Index">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
<activity android:name=".Registration">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
</application>
</manifest>

The app I am working on crashes when i try to go from one intent to the other, I've tried everything. code:

The Start class:
It as a very simple program, i designed two screen, and by pressing a button on the main screen i wanted the app to open the second screen, but unfortunately its not happening, the app keeps crushing over and over again.
package com.example.snakesnladders;
import android.os.Bundle;
import android.app.Activity;
import android.content.Intent;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
public class Start extends Activity implements OnClickListener {
Button start, settings;
TextView snakes, and, ladders;
ImageView snakePic;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.mainscreen);
init();
}
#Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
}
private void init() {
start = (Button) findViewById(R.id.btStart);
settings = (Button) findViewById(R.id.btSettings);
snakes = (TextView) findViewById(R.id.tvSnakes);
and = (TextView) findViewById(R.id.tvAnd);
ladders = (TextView) findViewById(R.id.tvLadders);
snakePic = (ImageView) findViewById(R.id.snakePic);
start.setOnClickListener(this);
settings.setOnClickListener(this);
}
#Override
public void onClick(View view) {
switch (view.getId()) {
case R.id.btStart:
break;
case R.id.btSettings:
Intent i = new Intent("com.example.snakesnladders.SET");
startActivity(i);
break;
default: break;
}
}
}
The Set class:
package com.example.snakesnladders;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
public class Set extends Activity implements OnClickListener {
Button sound, difficulty, back;
TextView settings;
ImageView snakePic;
#Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.setscreen);
init();
}
private void init() {
sound = (Button) findViewById(R.id.btSound);
difficulty = (Button) findViewById(R.id.btDifficulty);
back = (Button) findViewById(R.id.btBack);
settings = (TextView) findViewById(R.id.tvSetPage);
snakePic = (ImageView) findViewById(R.id.setSnakePic);
sound.setOnClickListener(this);
difficulty.setOnClickListener(this);
back.setOnClickListener(this);
}
#Override
public void onClick(View view) {
// TODO Auto-generated method stub
switch (view.getId()) {
case R.id.btSound:
String s = sound.getText().toString();
if (s.equals("Sound:on")) {
sound.setText("Sound:off");
ControlSounds.player.stop();
} else {
sound.setText("Sound:on");
ControlSounds.player.start();
}
break;
case R.id.btDifficulty:
break;
case R.id.btBack:
Intent i = new Intent(Set.this, Start.class);
startActivity(i);
finish();
break;
}
}
#Override
protected void onPause() {
// TODO Auto-generated method stub
super.onPause();
}
}
The manifest:
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.snakesnladders"
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" >
<activity
android:name=".Start"
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=".Set"
android:label="#string/app_name" >
<intent-filter>
<action android:name="com.example.snakesnladders.SET" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
</application>
</manifest>
mainscreen.xml:
<?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:background="#color/black"
android:orientation="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="175dp"
android:orientation="vertical" >
<TextView
android:id="#+id/tvSnakes"
android:layout_width="wrap_content"
android:layout_height="50dp"
android:layout_gravity="center"
android:text="Snakes"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textColor="#color/green"
android:textSize="30sp" />
<TextView
android:id="#+id/tvAnd"
android:layout_width="wrap_content"
android:layout_height="50dp"
android:layout_gravity="center"
android:text="#string/and"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textColor="#color/green"
android:textSize="30sp" />
<TextView
android:id="#+id/tvLadders"
android:layout_width="wrap_content"
android:layout_height="50dp"
android:layout_gravity="center"
android:text="Ladders"
android:textAppearance="?android:attr/textAppearanceMedium"
android:textColor="#color/green"
android:textSize="30sp" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="125dp"
android:orientation="vertical" >
<Button
android:id="#+id/btStart"
android:layout_width="250dp"
android:layout_height="60dp"
android:layout_gravity="center"
android:background="#drawable/buttonshape"
android:shadowColor="#A8A8A8"
android:shadowDx="0"
android:shadowDy="0"
android:shadowRadius="10"
android:text="Start New Game"
android:textColor="#FFFFFF"
android:textSize="30sp" />
<Button
android:id="#+id/btSettings"
android:layout_width="250dp"
android:layout_height="60dp"
android:layout_gravity="center"
android:background="#drawable/buttonshape"
android:shadowColor="#A8A8A8"
android:shadowDx="0"
android:shadowDy="0"
android:shadowRadius="10"
android:text="Settings"
android:textColor="#FFFFFF"
android:textSize="30sp" />
</LinearLayout>
<ImageView
android:id="#+id/snakePic"
android:layout_width="wrap_content"
android:layout_height="125dp"
android:layout_gravity="center"
android:layout_weight="0.47"
android:background="#color/black"
android:src="#drawable/snake" />
</LinearLayout>
setscreen.xml:
<?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:background="#color/black"
android:orientation="vertical" >
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/black"
android:orientation="vertical" >
<TextView
android:id="#+id/tvSetPage"
android:layout_width="wrap_content"
android:layout_height="60dp"
android:layout_gravity="center"
android:text="Settings"
android:textAppearance="?android:attr/textAppearanceLarge"
android:textColor="#color/green"
android:textSize="40sp" />
</LinearLayout>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:background="#color/black"
android:orientation="vertical" >
<Button
android:id="#+id/btSound"
android:layout_width="250dp"
android:layout_height="60dp"
android:layout_gravity="center"
android:background="#drawable/buttonshape"
android:shadowColor="#A8A8A8"
android:shadowDx="0"
android:shadowDy="0"
android:shadowRadius="10"
android:text="Sound:on"
android:textColor="#FFFFFF"
android:textSize="30sp" />
<Button
android:id="#+id/btDifficulty"
android:layout_width="250dp"
android:layout_height="60dp"
android:layout_gravity="center"
android:background="#drawable/buttonshape"
android:shadowColor="#A8A8A8"
android:shadowDx="0"
android:shadowDy="0"
android:shadowRadius="10"
android:text="Difficulty:easy"
android:textColor="#FFFFFF"
android:textSize="30sp" />
<Button
android:id="#+id/btBack"
android:layout_width="250dp"
android:layout_height="60dp"
android:layout_gravity="center"
android:background="#drawable/buttonshape"
android:shadowColor="#A8A8A8"
android:shadowDx="0"
android:shadowDy="0"
android:shadowRadius="10"
android:text="Back To Menu"
android:textColor="#FFFFFF"
android:textSize="30sp" />
</LinearLayout>
<ImageView
android:id="#+id/setSnakePic"
android:layout_width="wrap_content"
android:layout_gravity="center"
android:layout_weight="0.25"
android:background="#color/black"
android:src="#drawable/snake1" />
</LinearLayout>

Change this
Intent i = new Intent("com.example.snakesnladders.SET");
startActivity(i);
To
Intent i = new Intent(Start.this,Set.class);
startActivity(i);
And Change this
<activity
android:name=".Set"
android:label="#string/app_name" >
<intent-filter>
<action android:name="com.example.snakesnladders.SET" />
<category android:name="android.intent.category.DEFAULT" />
</intent-filter>
</activity>
To
<activity
android:name=".Set"
android:label="#string/app_name" >
</activity>
Use Explicit Intent's
To know why read
http://developer.android.com/guide/components/intents-filters.html
Explicit intents specify the component to start by name (the
fully-qualified class name). You'll typically use an explicit intent
to start a component in your own app, because you know the class name
of the activity or service you want to start. For example, start a new
activity in response to a user action or start a service to download a
file in the background.