Question

我想制作一个引用应用程序，显示引号，作者和收藏夹按钮。

我有一个自定义ListView，它有2个textViews和1个Toggle Button

我使用带有预先填充数据的SQLite（所以我已经拥有了所有数据）

如何在不使用SimpleCursorAdapter的情况下将报价和作者显示在2个文本视图中

我想使用ArrayList和ArrayAdapter

这是代码

DatabaseOpenHelper.java

public class DatabaseOpenHelper extends SQLiteAssetHelper {

private static final String DATABASE_NAME = "mqn.db";
private static final int DATABASE_VERSION = 1;

private static final String TABLE_NAME = "quote";
public static final String COLUMN_ID = "_id";
public static final String COLUMN_QUOTES = "quotesText";
public static final String COLUMN_AUTHOR= "author";
public static final String COLUMN_FAV = "fav";
public static final String COLUMN_GENRE = "genre";

private SQLiteDatabase database;

private final Context context;

// database path
private static String DATABASE_PATH;

/** constructor (Menambil PATH ke file database) */
public DatabaseOpenHelper(Context ctx) {
    super(ctx, DATABASE_NAME, null, DATABASE_VERSION);
    this.context = ctx;
    DATABASE_PATH = context.getFilesDir().getParentFile().getPath()
            + "/databases/";

}

/**
 * Creates a empty database on the system and rewrites it with your own
 * database.
 * */
public void create() throws IOException {
    boolean check = checkDataBase();

    SQLiteDatabase db_Read = null;

    // Creates empty database default system path
    db_Read = this.getWritableDatabase();
    db_Read.close();
    try {
        if (!check) {
            copyDataBase();
        }
    } catch (IOException e) {
        throw new Error("Error copying database");
    }
}

/**
 * Check if the database already exist to avoid re-copying the file each
 * time you open the application.
 *
 * @return true if it exists, false if it doesn't
 */
private boolean checkDataBase() {
    SQLiteDatabase checkDB = null;
    try {
        String myPath = DATABASE_PATH + DATABASE_NAME;
        checkDB = SQLiteDatabase.openDatabase(myPath, null,
                SQLiteDatabase.OPEN_READWRITE);
    } catch (SQLiteException e) {
        // database does't exist yet.
    }

    if (checkDB != null) {
        checkDB.close();
    }
    return checkDB != null ? true : false;
}

/**
 * Copies your database from your local assets-folder to the just created
 * empty database in the system folder, from where it can be accessed and
 * handled. This is done by transfering bytestream.
 * */
private void copyDataBase() throws IOException {

    // Open your local db as the input stream
    InputStream myInput = context.getAssets().open(DATABASE_NAME);

    // Path to the just created empty db
    String outFileName = DATABASE_PATH + DATABASE_NAME;

    // Open the empty db as the output stream
    OutputStream myOutput = new FileOutputStream(outFileName);

    // transfer bytes from the inputfile to the outputfile
    byte[] buffer = new byte[1024];
    int length;
    while ((length = myInput.read(buffer)) > 0) {
        myOutput.write(buffer, 0, length);
    }

    // Close the streams
    myOutput.flush();
    myOutput.close();
    myInput.close();

}

/** Start DB from here */

/** open the database */
public void open() throws SQLException {
    String myPath = DATABASE_PATH + DATABASE_NAME;
    database = SQLiteDatabase.openDatabase(myPath, null,
            SQLiteDatabase.OPEN_READWRITE);
}

/** close the database */
@Override
public synchronized void close() {
    if (database != null)
        database.close();
    super.close();
}

// insert a user into the database
public long insertUser(String quotesText, String author, String fav) {
    ContentValues initialValues = new ContentValues();
    initialValues.put(COLUMN_QUOTES, quotesText );
    initialValues.put(COLUMN_AUTHOR, author);
    initialValues.put(COLUMN_FAV, fav);
    return database.insert(TABLE_NAME, null, initialValues);
}

// updates a user
public boolean updateUser(long rowId, String fav) {
    ContentValues args = new ContentValues();
    args.put(COLUMN_FAV, fav);
    return database.update(TABLE_NAME, args, COLUMN_ID + "=" + rowId, null) > 0;
}

// retrieves a particular user
public Cursor getUser(long rowId) throws SQLException {
    Cursor mCursor = database.query(true, TABLE_NAME, new String[] {
                    COLUMN_ID, COLUMN_QUOTES, COLUMN_AUTHOR, COLUMN_FAV },
            COLUMN_ID + " = " + rowId, null, null, null, null, null);
    if (mCursor != null) {
        mCursor.moveToFirst();
    }

    return mCursor;
}

// delete a particular user
public boolean deleteContact(long rowId) {
    return database.delete(TABLE_NAME, COLUMN_ID + "=" + rowId, null) > 0;
}

// retrieves all users
public Cursor getAllUsers() {
    return database.query(TABLE_NAME, new String[] { COLUMN_ID,
                    COLUMN_QUOTES, COLUMN_AUTHOR, COLUMN_FAV }, null, null,
            null, null, null);
}

public Cursor getCertain(String valueGenre) {
    String WHERE = "genre = ?";
    String[] VALUE = new String[] {valueGenre};
    return database.query(TABLE_NAME, new String[]{COLUMN_ID,
                    COLUMN_QUOTES, COLUMN_AUTHOR, COLUMN_FAV}, WHERE, VALUE,
            null, null, null);
}

quotes_listview（自定义列表视图）

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent">

<LinearLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:orientation="horizontal"
    android:id="@+id/linearLayout">

    <TextView
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="New Text"
        android:id="@+id/txtQuote"
        style="@style/QuotesFont"
        android:layout_alignParentTop="true"
        android:layout_alignParentLeft="true"
        android:layout_alignParentStart="true"
        android:layout_rowWeight="1"
        android:layout_weight="1"
        android:layout_margin="15dp" />



    <ToggleButton
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:id="@+id/heartImage"
        android:layout_alignParentTop="true"
        android:layout_alignParentRight="true"
        android:layout_alignParentEnd="true"
        android:layout_marginTop="30dp"
        android:background="@drawable/fav"
        android:textOff=""
        android:textOn=""
        android:layout_rowWeight="1"
        android:layout_weight="3"
        android:descendantFocusability="blocksDescendants"
        android:layout_marginLeft="30dp"
        android:layout_marginRight="15dp" />

</LinearLayout>

<TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="New Text"
    android:id="@+id/txtAuthor"
    style="@style/AuthorFont"
    android:layout_below="@+id/linearLayout"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:layout_marginLeft="15dp"
    android:layout_marginBottom="5dp" />

<!--<TextView-->
    <!--android:layout_width="wrap_content"-->
    <!--android:layout_height="wrap_content"-->
    <!--android:text="New Text"-->
    <!--android:id="@+id/text2"-->
    <!--android:layout_below="@+id/text1"-->
    <!--android:layout_alignParentRight="true"-->
    <!--android:layout_alignParentEnd="true"-->
    <!--style="@style/AuthorFont"-->
    <!--android:layout_marginBottom="10dp"-->
    <!--android:layout_rowWeight="1"-->
    <!--android:layout_weight="1" />-->

ListOfQuotes.java

public class ListOfQuotes {

private String quote;
private String author;
private int fav;

public ListOfQuotes() {
}

public ListOfQuotes(String quote, String author, int fav) {
    this.quote = quote;
    this.author = author;
    this.fav = fav;
}

public ListOfQuotes(String quote, String author) {
    this.quote = quote;
    this.author = author;
}

public String getQuote() {
    return quote;
}

public void setQuote(String quote) {
    this.quote = quote;
}

public String getAuthor() {
    return author;
}

public void setAuthor(String author) {
    this.author = author;
}

public int getFav() {
    return fav;
}

public void setFav(int fav) {
    this.fav = fav;
}
}

QuotesAdapter.java

public class QuotesAdapter extends BaseAdapter {

private Activity activity;
private ArrayList<ListOfQuotes> data;
private LayoutInflater inflater;
boolean isSelected = false;
ToggleButton imgHeart;

public QuotesAdapter(Activity activity, ArrayList<ListOfQuotes> data) {
    this.activity = activity;
    this.data = data;
    this.inflater = (LayoutInflater) activity.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
}


@Override
public int getCount() {
    return data.size();
}

@Override
public Object getItem(int position) {
    return data.get(position);
}

@Override
public long getItemId(int position) {
    return position;
}

@Override
public View getView(int position, View convertView, ViewGroup parent) {
    ListOfQuotes loq = data.get(position);
    if(convertView == null)
    {
        convertView = inflater.inflate(R.layout.quotes_listview, null);
    }

    TextView txtQuotes = (TextView) convertView.findViewById(R.id.txtQuote);
    TextView txtAuthors = (TextView) convertView.findViewById(R.id.txtAuthor);
    imgHeart = (ToggleButton) convertView.findViewById(R.id.heartImage);


    txtQuotes.setText(loq.getQuote());
    txtAuthors.setText(loq.getAuthor());

    return convertView;
}
}

QuotesActivity.java

public class QuotesActivity extends AppCompatActivity {

ListView quotesList;
DatabaseOpenHelper myDbHelper;

ArrayList<ListOfQuotes> arrQuotes;
QuotesAdapter adapter;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_quotes);

    myDbHelper = new DatabaseOpenHelper(this);

    try {
        // check if database exists in app path, if not copy it from assets
        myDbHelper.create();
    } catch (IOException ioe) {
        throw new Error("Unable to create database");
    }

    try {
        // open the database
        myDbHelper.open();
        myDbHelper.getWritableDatabase();
    } catch (SQLException sqle) {
        throw sqle;
    }

    arrQuotes = new ArrayList<ListOfQuotes>();
    quotesList = (ListView) findViewById(R.id.quotesList);
    adapter = new QuotesAdapter(QuotesActivity.this, arrQuotes);
    quotesList.setAdapter(adapter);

此后我不知道怎么做。

Answer 1

尝试使用此代码并将您的额外字段放在.xml文件和.java文件

中

<强> ListViewActivity.java

public class ListViewActivity extends Activity
{
    ListView listCustom;
    private SQLiteDatabase db;
    ProductDatabase customerDB;
    ProductAdapter customAdapter;
    static final String DATABASE_NAME = "login.db";
    public static String DB_PATH; 
    private ArrayList<LevelList> results = new ArrayList<LevelList>();
    @Override
    protected void onCreate(Bundle savedInstanceState) 
    {
       super.onCreate(savedInstanceState);
       setContentView(R.layout.product_list);

        levelLists = new ArrayList<LevelList>();
        customerDB = new ProductDatabase(getApplicationContext());
        customerDB = customerDB.open();
        listCustom = (ListView) findViewById(R.id.listView1);
        mainMenu();
    }

    public void mainMenu()
    {
        results.clear();
        DB_PATH = "/data/data/com.gt.invoicemaker/databases/";
        String myPath = DB_PATH + DATABASE_NAME;
        db = SQLiteDatabase.openDatabase(myPath, null,SQLiteDatabase.OPEN_READONLY);  
          final Cursor c = db.rawQuery("SELECT  ID AS _id, USERID, INAME, IPRICE FROM ITEM, null);
          // Note: Master is the one table in External db. Here we trying to access the records of table from external db. 
         if (c != null ) {
                if  (c.moveToFirst()) {
                    do {
                        LevelList results1 = new LevelList();
                        int _id = c.getInt(c.getColumnIndex("_id"));
                        String userName = c.getString(c.getColumnIndex("INAME"));

                        results1.id = _id;
                        results1.item = userName;
                        results.add(results1);
                    }while (c.moveToNext());
                }
         }
                customAdapter = new ProductAdapter(getApplicationContext(), results);
                listCustom.setAdapter(customAdapter);
    }
  }
}

<强> ProductAdapter.java

public class ProductAdapter extends BaseAdapter {

    private Context mContext;
    private List<LevelList> listItem;

      public ProductAdapter(Context c,List<LevelList> listItem) {
          mContext = c;
          this.listItem = listItem;
      }

      @Override
      public int getCount() {
          // TODO Auto-generated method stub
          return listItem.size();
      }

      @Override
      public Object getItem(int position) {
          // TODO Auto-generated method stub
          return listItem;
      }

      @Override
      public long getItemId(int position) {
          // TODO Auto-generated method stub
          return position;
      }

      @Override
      public View getView(int position, View convertView, ViewGroup parent) {
          // TODO Auto-generated method stub
          LayoutInflater inflater = (LayoutInflater) mContext
              .getSystemService(Context.LAYOUT_INFLATER_SERVICE);

          View rowView=inflater.inflate(R.layout.singleproduct, null,true);

              TextView textView = (TextView) rowView.findViewById(R.id.single_product);
              textView.setText(listItem.get(position).item);
          return rowView;
      }
}

<强> product_list.xml

 <?xml version="1.0" encoding="utf-8"?>
        <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
            android:layout_width="match_parent"
            android:layout_height="match_parent" >

                    <ListView
                        android:id="@+id/listView1"
                        android:layout_width="match_parent"
                        android:layout_height="wrap_content"
                        android:layout_above="@+id/addnew"
                        android:layout_below="@+id/mainview"
                        android:layout_centerHorizontal="true"
                        android:layout_marginLeft="10dp"
                        android:layout_marginRight="10dp"
                        android:layout_marginTop="7dp"
                        android:layout_marginBottom="7dp"
                        android:scrollbars="none" >

                    </ListView>

        </RelativeLayout>

<强> singleproduct.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:orientation="vertical" >

        <TextView
            android:id="@+id/single_product"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_centerVertical="true"
            android:textColor="@android:color/white"
            android:layout_marginLeft="15dp"
            android:text="" />

</LinearLayout>

<强> DataBaseHelper.java

public class DataBaseHelper extends SQLiteOpenHelper
{
    public DataBaseHelper(Context context, String name,CursorFactory factory, int version) 
    {
               super(context, name, factory, version);
    }
    // Called when no database exists in disk and the helper class needs
    // to create a new one.
    @Override
    public void onCreate(SQLiteDatabase _db) 
    {
            _db.execSQL(ProductDatabase.DATABASE_CREATE);
    }
    // Called when there is a database version mismatch meaning that the version
    // of the database on disk needs to be upgraded to the current version.
    @Override
    public void onUpgrade(SQLiteDatabase _db, int _oldVersion, int _newVersion) 
    {
            // Log the version upgrade.
            Log.w("TaskDBAdapter", "Upgrading from version " +_oldVersion + " to " +_newVersion + ", which will destroy all old data");


            // Upgrade the existing database to conform to the new version. Multiple
            // previous versions can be handled by comparing _oldVersion and _newVersion
            // values.
            // The simplest case is to drop the old table and create a new one.
            _db.execSQL("DROP TABLE IF EXISTS " + "TEMPLATE");
            // Create a new one.
            onCreate(_db);
    }
}

从SQLite获取数据到ListView的ArrayList

1 个答案: