android sqlite

2013-09-21 23:49:07 +03:00
parent ef85815469
commit 0724d1ae3b
11 changed files with 360 additions and 0 deletions
@@ -0,0 +1,185 @@
+package com.hmkcode.android.sqlite;
+
+import java.util.LinkedList;
+import java.util.List;
+
+import com.hmkcode.android.model.Book;
+
+import android.content.ContentValues;
+import android.content.Context;
+import android.database.Cursor;
+import android.database.sqlite.SQLiteDatabase;
+import android.database.sqlite.SQLiteOpenHelper;
+import android.util.Log;
+
+public class MySQLiteHelper extends SQLiteOpenHelper {
+	
+	// Database Version
+    private static final int DATABASE_VERSION = 1;
+    // Database Name
+    private static final String DATABASE_NAME = "BookDB";
+   
+	public MySQLiteHelper(Context context) {
+		super(context, DATABASE_NAME, null, DATABASE_VERSION);	
+	}
+
+	@Override
+	public void onCreate(SQLiteDatabase db) {
+		// SQL statement to create book table
+		String CREATE_BOOK_TABLE = "CREATE TABLE books ( " +
+                "id INTEGER PRIMARY KEY AUTOINCREMENT, " + 
+				"title TEXT, "+
+				"author TEXT )";
+		
+		// create books table
+		db.execSQL(CREATE_BOOK_TABLE);
+	}
+
+	@Override
+	public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
+		// Drop older books table if existed
+        db.execSQL("DROP TABLE IF EXISTS books");
+        
+        // create fresh books table
+        this.onCreate(db);
+	}
+	//---------------------------------------------------------------------
+   
+	/**
+     * CRUD operations (create "add", read "get", update, delete) book + get all books + delete all books
+     */
+	
+	// Books table name
+    private static final String TABLE_BOOKS = "books";
+    
+    // Books Table Columns names
+    private static final String KEY_ID = "id";
+    private static final String KEY_TITLE = "title";
+    private static final String KEY_AUTHOR = "author";
+    
+    private static final String[] COLUMNS = {KEY_ID,KEY_TITLE,KEY_AUTHOR};
+    
+	public void addBook(Book book){
+		Log.d("addBook", book.toString());
+		// 1. get reference to writable DB
+		SQLiteDatabase db = this.getWritableDatabase();
+		 
+		// 2. create ContentValues to add key "column"/value
+        ContentValues values = new ContentValues();
+        values.put(KEY_TITLE, book.getTitle()); // get title 
+        values.put(KEY_AUTHOR, book.getAuthor()); // get author
+ 
+        // 3. insert
+        db.insert(TABLE_BOOKS, // table
+        		null, //nullColumnHack
+        		values); // key/value -> keys = column names/ values = column values
+        
+        // 4. close
+        db.close(); 
+	}
+	
+	public Book getBook(int id){
+
+		// 1. get reference to readable DB
+		SQLiteDatabase db = this.getReadableDatabase();
+		 
+		// 2. build query
+        Cursor cursor = 
+        		db.query(TABLE_BOOKS, // a. table
+        		COLUMNS, // b. column names
+        		" id = ?", // c. selections 
+                new String[] { String.valueOf(id) }, // d. selections args
+                null, // e. group by
+                null, // f. having
+                null, // g. order by
+                null); // h. limit
+        
+        // 3. if we got results get the first one
+        if (cursor != null)
+            cursor.moveToFirst();
+ 
+        // 4. build book object
+        Book book = new Book();
+        book.setId(Integer.parseInt(cursor.getString(0)));
+        book.setTitle(cursor.getString(1));
+        book.setAuthor(cursor.getString(2));
+
+		Log.d("getBook("+id+")", book.toString());
+
+        // 5. return book
+        return book;
+	}
+	
+	// Get All Books
+    public List<Book> getAllBooks() {
+        List<Book> books = new LinkedList<Book>();
+
+        // 1. build the query
+        String query = "SELECT  * FROM " + TABLE_BOOKS;
+ 
+    	// 2. get reference to writable DB
+        SQLiteDatabase db = this.getWritableDatabase();
+        Cursor cursor = db.rawQuery(query, null);
+ 
+        // 3. go over each row, build book and add it to list
+        Book book = null;
+        if (cursor.moveToFirst()) {
+            do {
+            	book = new Book();
+                book.setId(Integer.parseInt(cursor.getString(0)));
+                book.setTitle(cursor.getString(1));
+                book.setAuthor(cursor.getString(2));
+
+                // Add book to books
+                books.add(book);
+            } while (cursor.moveToNext());
+        }
+        
+		Log.d("getAllBooks()", books.toString());
+
+        // return books
+        return books;
+    }
+	
+	 // Updating single book
+    public int updateBook(Book book) {
+
+    	// 1. get reference to writable DB
+        SQLiteDatabase db = this.getWritableDatabase();
+ 
+		// 2. create ContentValues to add key "column"/value
+        ContentValues values = new ContentValues();
+        values.put("title", book.getTitle()); // get title 
+        values.put("author", book.getAuthor()); // get author
+ 
+        // 3. updating row
+        int i = db.update(TABLE_BOOKS, //table
+        		values, // column/value
+        		KEY_ID+" = ?", // selections
+                new String[] { String.valueOf(book.getId()) }); //selection args
+        
+        // 4. close
+        db.close();
+        
+        return i;
+        
+    }
+
+    // Deleting single book
+    public void deleteBook(Book book) {
+
+    	// 1. get reference to writable DB
+        SQLiteDatabase db = this.getWritableDatabase();
+        
+        // 2. delete
+        db.delete(TABLE_BOOKS,
+        		KEY_ID+" = ?",
+                new String[] { String.valueOf(book.getId()) });
+        
+        // 3. close
+        db.close();
+        
+		Log.d("deleteBook", book.toString());
+
+    }
+}