在我的应用程序中，我从 Google Play 插入用户访问应用程序包名称并将其保存在数据库中。我只显示来自安装应用程序包名称在数据库中的应用程序。
这些值成功插入数据库，但是当我PlayStoreApps在这一行的类中 进行比较时if (arraylist.equals(p.packageName))：
public class PlayStoreApps extends Activity implements OnItemClickListener {
private static final boolean INCLUDE_SYSTEM_APPS = false;
DatabaseHandler db;
private ListView mAppsList;
private AppListAdapter mAdapter;
private List<App> mApps;
db = new DatabaseHandler(this);
private List<App> loadInstalledApps(boolean includeSysApps) {
List<App> apps = new ArrayList<App>();
// the package manager contains the information about all installed apps
PackageManager packageManager = getPackageManager();
List<PackageInfo> packs = packageManager.getInstalledPackages(0);
List arraylist = db.getAllApps();
for (int i = 0; i < packs.size(); i++) {
PackageInfo p = packs.get(i);
ApplicationInfo applicationInfo = p.applicationInfo;
if (arraylist.equals(p.packageName)) {
// if ( (p.packageName).equals(arraylist))
App app = new App();
app.setTitle(p.applicationInfo.loadLabel(packageManager).toString());
app.setPackageName(p.packageName);
app.setVersionName(p.versionName);
app.setVersionCode(p.versionCode);
CharSequence description = p.applicationInfo.loadDescription(packageManager);
app.setDescription(description != null ?
description.toString() : "");
apps.add(app);
}
}
return apps;
}
public class Search extends Activity {
/** Called when the activity is first created. */
DatabaseHandler db;
WebView web;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.search);
db = new DatabaseHandler(this);
String id= url.substring(Standard .length(), url.indexOf("&"));
db.addContact(new Contact(id));
Log.d("Reading: ", "Reading all contacts..");
List<Contact> contacts = db.getAllContacts();
for (Contact cn : contacts) {
String log = "Id: "+cn.getID()+" ,Name: " + cn.getName() ;
// String log = "Id: "+cn.getID()+" ,Name: " + cn.getName() + " ,Phone: " + cn.getPhoneNumber();
// Writing Contacts to log
Log.d("Name: ", log);
}
view.loadUrl(url);
return true;
}
public class DatabaseHandler extends SQLiteOpenHelper {
private static final int DATABASE_VERSION = 1;
private static final String DATABASE_NAME = "contactsManager";
private static final String TABLE_CONTACTS = "contacts";
private static final String KEY_ID = "id";
private static final String KEY_NAME = "name";
public DatabaseHandler(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
// Creating Tables
@Override
public void onCreate(SQLiteDatabase db) {
// String CREATE_CONTACTS_TABLE = "CREATE TABLE " + TABLE_CONTACTS + "("+ KEY_ID + " INTEGER PRIMARY KEY," + KEY_NAME + " TEXT,"+ KEY_PH_NO + " TEXT" + ")";
String CREATE_CONTACTS_TABLE = "CREATE TABLE " + TABLE_CONTACTS + "("+ KEY_ID + " INTEGER PRIMARY KEY," + KEY_NAME + " TEXT" + " UNIQUE " + ")";
db.execSQL(CREATE_CONTACTS_TABLE);
}
// Upgrading database
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// Drop older table if existed
db.execSQL("DROP TABLE IF EXISTS " + TABLE_CONTACTS);
// Create tables again
onCreate(db);
}
/**
* All CRUD(Create, Read, Update, Delete) Operations
*/
// Adding new contact
void addContact(Contact contact) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_NAME, contact.getName()); // Contact Name
// values.put(KEY_PH_NO, contact.getPhoneNumber()); // Contact Phone
// Inserting Row
db.insert(TABLE_CONTACTS, null, values);
db.close(); // Closing database connection
}
// Getting single contact
Contact getContact(int id) {
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.query(TABLE_CONTACTS, new String[] { KEY_ID, KEY_NAME }, KEY_ID + "=?", new String[] { String.valueOf(id) }, null, null, null, null);
if (cursor != null)
cursor.moveToFirst();
Contact contact = new Contact(Integer.parseInt(cursor.getString(0)), cursor.getString(1));
// return contact
return contact;
}
// Getting All Contacts
public List<Contact> getAllContacts() {
List<Contact> contactList = new ArrayList<Contact>();
// Select All Query
String selectQuery = "SELECT * FROM " + TABLE_CONTACTS;
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
Contact contact = new Contact();
contact.setID(Integer.parseInt(cursor.getString(0)));
contact.setName(cursor.getString(1));
//contact.setPhoneNumber(cursor.getString(2));
// Adding contact to list
contactList.add(contact);
} while (cursor.moveToNext());
}
// return contact list
return contactList;
}
// Updating single contact
public int updateContact(Contact contact) {
SQLiteDatabase db = this.getWritableDatabase();
ContentValues values = new ContentValues();
values.put(KEY_NAME, contact.getName());
// values.put(KEY_PH_NO, contact.getPhoneNumber());
// updating row
return db.update(TABLE_CONTACTS, values, KEY_ID + " = ?", new String[] { String.valueOf(contact.getID()) });
}
// Deleting single contact
public void deleteContact(Contact contact) {
SQLiteDatabase db = this.getWritableDatabase();
db.delete(TABLE_CONTACTS, KEY_ID + " = ?", new String[] { String.valueOf(contact.getID()) });
db.close();
}
public int deleteContact() {
try {
SQLiteDatabase db = this.getWritableDatabase();
return db.delete(TABLE_CONTACTS, null, null);
} catch (Exception e) {
e.printStackTrace();
}
return 0;
}
// Getting contacts Count
public int getContactsCount() {
String countQuery = "SELECT * FROM " + TABLE_CONTACTS;
SQLiteDatabase db = this.getReadableDatabase();
Cursor cursor = db.rawQuery(countQuery, null);
cursor.close();
// return count
return cursor.getCount();
}
public ArrayList<String> getAllApps() {
String selectQuery = "SELECT * FROM "+TABLE_CONTACTS;
ArrayList<String> apps = new ArrayList<String>();
SQLiteDatabase db = this.getWritableDatabase();
Cursor cursor = db.rawQuery(selectQuery, null);
// looping through all rows and adding to list
if (cursor.moveToFirst()) {
do {
apps.add(cursor.getString(cursor.getColumnIndex(KEY_NAME)));
} while (cursor.moveToNext());
}
// return list
return apps;
}
}