Error using Intent [im just a student learning]

[mikred11]

I get an error every time i click the navdown button "The application have been stopped unexpectedly Please try again". what does it mean?? im a new student in mobile developing.. please help i need to learn about this error

public class chapter1 extends Activity {
	MediaPlayer sButton;
	Intent intent;
	private Button navup;
	private Button navdown;
	private WebView view = null;
	private String url = null;
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.chapter1);
		url = getResources().getString(R.string.c1);
		view = (WebView) findViewById(R.id.html1);
		view.loadUrl(url);
		view.setInitialScale(80);		
		navlist();
		sButton = MediaPlayer.create(this, R.raw.page3);
	}
	private void navlist() {
		navup = (Button)findViewById(R.id.prev);
		navdown = (Button)findViewById(R.id.next);
			navup.setOnClickListener(new View.OnClickListener() {
			
			@Override
			public void onClick(View v) {
				intent = new Intent(chapter1.this, chapters.class);
				startActivity(intent);
				sButton.start();
			}
		});					
		       navdown.setOnClickListener(new View.OnClickListener() {
			
			@Override
			public void onClick(View v) {
				intent = new Intent(chapter1.this, chapter2.class);
				startActivity(intent);
				sButton.start();
				
			}
		});
	}		
}

[peter_budo]

Can you post whole code? What you using as reference to write code?

[mikred11]

Can you post whole code? What you using as reference to write code?

sir this is chapter1.java

public class chapter1 extends Activity {
	MediaPlayer sButton;
	Intent intent;
	private Button navup;
	private Button navdown;
	private WebView view = null;
	private String url = null;
	
	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.chapter1);
		url = getResources().getString(R.string.c1);
		view = (WebView) findViewById(R.id.html1);
		view.loadUrl(url);
		view.setInitialScale(80);		
		navlist();
		sButton = MediaPlayer.create(this, R.raw.page3);
	}

	private void navlist() {
		navup = (Button)findViewById(R.id.prev);
		navdown = (Button)findViewById(R.id.next);
		
		navup.setOnClickListener(new View.OnClickListener() {
			
			@Override
			public void onClick(View v) {
				intent = new Intent(chapter1.this, chapters.class);
				startActivity(intent);
				sButton.start();
			}
		});
					
		navdown.setOnClickListener(new View.OnClickListener() {
			
			@Override
			public void onClick(View v) {
				intent = new Intent(chapter1.this, chapter2.class);
				startActivity(intent);
				sButton.start();
				
			}
		});
	}		
}

[mikred11]

and chapter1.java is what you see above and this is chapter2.java

public class chapter2 extends Activity {
	MediaPlayer sButton;
	Intent intent;
	private Button navup;
	private Button navdown;
	private WebView view1 = new WebView(null);
	private String url1 = null;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.chapter2);
		url1 = getResources().getString(R.string.c2);
		view1 = (WebView) findViewById(R.id.html2);
		view1.loadUrl(url1);
		view1.setInitialScale(80);
		navlist();
		sButton = MediaPlayer.create(this, R.raw.page3);
	}
	
	private void navlist() {
		navup = (Button)findViewById(R.id.prev);
		
		navup.setOnClickListener(new View.OnClickListener() {
			
			@Override
			public void onClick(View v) {
				intent = new Intent(chapter2.this, chapter1.class);
				startActivity(intent);
				sButton.start();
			}
		});
		
		navdown = (Button)findViewById(R.id.next);
		
		navdown.setOnClickListener(new View.OnClickListener() {
			
			@Override
			public void onClick(View v) {
				intent = new Intent(chapter2.this, chapter3.class);
				startActivity(intent);
				sButton.start();
				
			}
		});
	}

}

[mikred11]

and this is its manifest

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.hummingbird.mik"
      android:versionCode="1"
      android:versionName="1.0">
    <uses-sdk android:minSdkVersion="3" />

    <application android:icon="@drawable/icon">
        <activity android:name=".AndroidHummingBird" android:label="Main View">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
        <activity android:name=".chapters" android:label="@string/chapters">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
		<activity android:name=".chapter1" android:label="@string/chapter1">
			<intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
		</activity>
		<activity android:name=".chapter2" android:label="@string/chapter2">
		</activity>
		<activity android:name=".chapter3" android:label="@string/chapter3">
		</activity>
		<activity android:name=".chapter4" android:label="@string/chapter4">
		</activity>
    </application>
</manifest>

and the layout xml of chapter1.java

<?xml version="1.0" encoding="utf-8"?>
<!-- This XML file defines the layout for the About view. -->
<LinearLayout
  xmlns:android="http://schemas.android.com/apk/res/android"
  android:layout_width="fill_parent"
  android:orientation="vertical"
  android:layout_height="fill_parent"
  android:background="#EBEFFB"
  >
  
  <FrameLayout 
  	android:layout_height="fill_parent"
  	android:layout_width="fill_parent"
  	android:layout_gravity="bottom"
  	android:id="@+id/frame01">
 
    <WebView 
  		android:layout_height="fill_parent"
  		android:layout_width="fill_parent"
  		android:id="@+id/html1"
  		android:background="@drawable/background">
  	</WebView>
  	
  	<LinearLayout 
  		android:layout_height="50dp"
  		android:layout_width="fill_parent"
  		android:background="#657383"
  		android:layout_gravity="bottom"
  		android:id="@+id/controls"
  		android:orientation="horizontal">
  		
  		<LinearLayout 
  			android:layout_height="40dp"
  			android:layout_width="fill_parent"
  			android:background="#657383"
  			android:layout_gravity="center_vertical"
  			android:id="@+id/chandler"
  			android:orientation="horizontal">
  			
  			<LinearLayout 
  				android:layout_height="wrap_content"
  				android:layout_width="wrap_content"
  				android:background="#657383"
  				android:layout_gravity="center_vertical">
  				
  			<LinearLayout 
  				android:layout_height="wrap_content"
  				android:layout_width="wrap_content"
  				android:background="#657383"
  				android:layout_gravity="center_vertical">
  				
  				<Button 
  					android:layout_height="40dp"
  					android:layout_width="160dp"
  					android:id="@+id/prev"  					
  					android:textStyle="bold"
  					android:text="^"
  					android:layout_gravity="center_horizontal"/>
  			</LinearLayout>    
  			  			
  			<LinearLayout 
  				android:layout_height="wrap_content"
  				android:layout_width="fill_parent"
  				android:background="#657383"
  				android:layout_gravity="center_vertical">
  				
  				<Button 
  					android:layout_width="160dp" 
  					android:layout_height="40dp" 
  					android:layout_gravity="center_horizontal" 
  					android:id="@+id/next"
  					android:gravity="center"
  					android:text="v">
  				</Button>
  			</LinearLayout>
  		
  		</LinearLayout>	  			
  		</LinearLayout>  		
  	</LinearLayout>
</FrameLayout>
</LinearLayout>