if we have FavoritePage class:

public class FavoritePage {

private String name;

private String url;

private int visitCount;

public String getName() {

return name;

}

public String getUrl() {

return url;

}

public int getVisitCount() {

return visitCount;

}

public void setName(String name) {

this.name = name;

}

public void setUrl(String url) {

this.url = url;

}

public void setVisitCount(int visitCount) {

this.visitCount = visitCount;

}

public FavoritePage(String name, String url, int visitCount) {

super();

this.name = name;

this.url = url;

this.visitCount = visitCount;

}

}

and singleton Database class that hosts a collection of FavoritePage instances and provides the following methods: - static void load( File f ) throws IOException, ClassNotFoundException load the database (into the singleton variable) from the specified file - void save( File f ) throws IOException save this database to the specified file - int getPageCount() - FavoritePage getPage( int ) return the site at the specified index - List getPages() return the list of sites, wrapped to be unmodifiable (see Collections . unmodifiableList()).

//DataBaseClass

class DataBaseClass{

private static DataBaseClass obj=new DataBaseClass();//Early, instance will be created at load time

private DataBaseClass(){}

private static List pages;

private static File databaseFile;

public static DataBaseClass getObject(){

return obj;

}

//load the database (into the singleton variable) from the specified file

static void load( File f ) throws IOException, ClassNotFoundException{

databaseFile = f;

BufferedReader br = new BufferedReader(new FileReader(f));

String str;

while ((str = br.readLine()) != null) {

int i=0;

String name = null,url = null,count = null;

//assume database file is have page name , url and count in space seperated file

StringTokenizer st = new StringTokenizer(str, " ");

while(st.hasMoreTokens()) {

if(i== 0)

name = st.nextToken(); //make first part as page name

if(i == 1)

url = st.nextToken(); // make second part as url of page

if(i==2)

count = st.nextToken();

}

int visitCount = Integer.parseInt(count);

FavoritePage favPage = new FavoritePage(name, url, visitCount);

pages.add(favPage);

//System.out.println(str);

}

}

//save this database to the specified file

void save( File f ) throws IOException{

f = databaseFile;

}

//return the site at the specified index

int getPageCount() {

return pages.size();

}

//return the list of sites, wrapped to be unmodifiable

FavoritePage getPage(int index) {

return pages.get(index);

}

List getPages() {

return pages;

}

}

and we have two activities: site list and site detail like that:

site_list:

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"  xmlns:tools="http://schemas.android.com/tools"  android:gravity="center"  android:orientation="vertical"> <Button   android:id="@+id/button1"  android:layout_width="207dp"  android:layout_height="42dp"  android:text="@string/button1"  tools:layout_editor_absoluteX="89dp"  tools:layout_editor_absoluteY="16dp"/> <Button   android:id="@+id/button2"  android:layout_width="207dp"  android:layout_height="42dp"  android:text="@string/button2"  tools:layout_editor_absoluteX="89dp"  tools:layout_editor_absoluteY="58dp" /> <Button   android:id="@+id/button3"  android:layout_width="207dp"  android:layout_height="42dp"  android:text="@string/button3"  tools:layout_editor_absoluteX="89dp"  tools:layout_editor_absoluteY="100dp" /> <Button   android:id="@+id/button4"  android:layout_width="207dp"  android:layout_height="42dp"  android:text="@string/button4"  tools:layout_editor_absoluteX="89dp"  tools:layout_editor_absoluteY="142dp" /> <Button   android:id="@+id/button5"  android:layout_width="207dp"  android:layout_height="42dp"  android:text="@string/button5"  tools:layout_editor_absoluteX="89dp"  tools:layout_editor_absoluteY="184dp" /> <Button   android:id="@+id/button6"  android:layout_width="207dp"  android:layout_height="42dp"  android:text="@string/button6"  tools:layout_editor_absoluteX="89dp"  tools:layout_editor_absoluteY="226dp" /> <Button   android:id="@+id/button7"  android:layout_width="207dp"  android:layout_height="42dp"  android:text="@string/button7"  tools:layout_editor_absoluteX="89dp"  tools:layout_editor_absoluteY="268dp" /> <Button   android:id="@+id/button8"  android:layout_width="207dp"  android:layout_height="42dp"  android:text="@string/button8"  tools:layout_editor_absoluteX="89dp"  tools:layout_editor_absoluteY="310dp" /> LinearLayout> 

site_detail:

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:paddingRight="16dp"  android:paddingLeft="16dp"  android:paddingBottom="16dp"  android:paddingTop="16dp"  android:orientation="vertical"> <TextView  android:id="@+id/text_visit"  android:layout_width="match_parent"  android:layout_height="0dp"  android:layout_weight="1"  android:text="@string/text_visit" /> <TextView  android:id="@+id/text_url"  android:layout_width="match_parent"  android:layout_height="9dp"  android:layout_weight="1"  android:text="@string/text_url" /> <WebView  android:id="@+id/web_view"  android:layout_width="366dp"  android:layout_height="413dp">WebView> LinearLayout> 

How can do that in Android Studio:

Pressing a button on the site list should increment the visit count, save the updated database, and show the detail activity which should display the URL, visit count and a WebView showing site. // You can use fragments