Android Programlama -45 SQLite Provider Class

Merhaba arkadaşlar bu gün ki makalem de SQLite database’inde provider class’ına değineceğim.

Bir önceki makalemde Contract class’ına değinmiştim. Okumadıysanız öncelikle onu okumanızı tavsiye ederim. Buradan okuyabilirsiniz.

package com.example.user.finalyproject.DataBase;

import android.content.ContentProvider;
import android.content.ContentUris;
import android.content.ContentValues;
import android.content.UriMatcher;
import android.database.Cursor;
import android.database.sqlite.SQLiteDatabase;
import android.net.Uri;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.widget.Toast;

public class Provider extends ContentProvider {
public static final int PRODUCTS = ..;
private static final int PRODUCT_ID = ..;
private static final UriMatcher sUriMatcher = new UriMatcher(UriMatcher.NO_MATCH);

static {
sUriMatcher.addURI(ProductContract.CONTENT_AUTHORITY, ProductContract.PATH_PRODUCTS, PRODUCTS);
sUriMatcher.addURI(ProductContract.CONTENT_AUTHORITY, ProductContract.PATH_PRODUCTS + "/#", PRODUCT_ID);
}

private DbHelper mdbHelper;

@Override
public boolean onCreate() {
mdbHelper = new DbHelper(getContext());
return true;
}

@Nullable
@Override
public Cursor query(@NonNull Uri uri, @Nullable String[] strings, @Nullable String s, @Nullable String[] strings1, @Nullable String s1) {
SQLiteDatabase db = mdbHelper.getReadableDatabase();
Cursor cursor;
int match = sUriMatcher.match(uri);
switch (match) {
case PRODUCTS:
cursor = db.query(ProductContract.ProductEntry.TABLE_NAME, strings, s, strings1, null, null, s1);
break;
case PRODUCT_ID:
s = ProductContract.ProductEntry._ID + "=?";
strings1 = new String[]{String.valueOf(ContentUris.parseId(uri))};
cursor = db.query(ProductContract.ProductEntry.TABLE_NAME, strings, s, strings1, null, null, s1);
break;
default:
throw new IllegalArgumentException("Cannot query unknown URI" + uri);
}

cursor.setNotificationUri(getContext().getContentResolver(), uri);

return cursor;
}

@Nullable
@Override
public String getType(@NonNull Uri uri) {
final int match = sUriMatcher.match(uri);
switch (match) {
case PRODUCTS:
return ProductContract.ProductEntry.CONTENT_LIST_TYPE;
case PRODUCT_ID:
return ProductContract.ProductEntry.CONTENT_ITEM_TYPE;
default:
throw new IllegalStateException("Unknown URI " + uri + " with match " + match);
}
}

@Nullable
@Override
public Uri insert(@NonNull Uri uri, @Nullable ContentValues contentValues) {
final int match = sUriMatcher.match(uri);
switch (match) {
case PRODUCTS:
return insertProduct(uri, contentValues);
default:
throw new IllegalArgumentException("Insertion is not supported for " + uri);
}
}

@Override
public int delete(@NonNull Uri uri, @Nullable String s, @Nullable String[] strings) {
SQLiteDatabase db = mdbHelper.getWritableDatabase();

int rowsDeleted;

final int match = sUriMatcher.match(uri);
switch (match) {
case PRODUCTS:
rowsDeleted = db.delete(ProductContract.ProductEntry.TABLE_NAME, s, strings);
break;
case PRODUCT_ID:
s = ProductContract.ProductEntry._ID + "=?";
strings = new String[]{String.valueOf(ContentUris.parseId(uri))};
rowsDeleted = db.delete(ProductContract.ProductEntry.TABLE_NAME, s, strings);
break;
default:
throw new IllegalArgumentException("You cannot delete " + uri);
}

if (rowsDeleted != 0) {
getContext().getContentResolver().notifyChange(uri, null);
}

return rowsDeleted;
}

@Override
public int update(@NonNull Uri uri, @Nullable ContentValues contentValues, @Nullable String s, @Nullable String[] strings) {
if (contentValues.containsKey(ProductContract.ProductEntry.COLUMN_PRODUCT_NAME)) {
String name = contentValues.getAsString(ProductContract.ProductEntry.COLUMN_PRODUCT_NAME);
if (name == null) {
throw new IllegalArgumentException("Enter the product name");
}
}

if (contentValues.containsKey(ProductContract.ProductEntry.COLUMN_PRODUCT_QUANTITY)) {
Integer quantity = contentValues.getAsInteger(ProductContract.ProductEntry.COLUMN_PRODUCT_QUANTITY);
if (quantity != null && quantity < 0) {
throw new IllegalArgumentException("enter the quentity");
}
}

if (contentValues.containsKey(ProductContract.ProductEntry.COLUMN_PRODUCT_PRICE)) {
Integer price = contentValues.getAsInteger(ProductContract.ProductEntry.COLUMN_PRODUCT_PRICE);
if (price != null && price < 0) {
throw new IllegalArgumentException("price will be correct");
}
}

if (contentValues.size() == 0) {
return 0;
}

SQLiteDatabase db = mdbHelper.getReadableDatabase();
int rowsUpdated = db.update(ProductContract.ProductEntry.TABLE_NAME, contentValues, s, strings);
if (rowsUpdated == -1) {
Toast.makeText(getContext(), "Update is not succesful", Toast.LENGTH_SHORT).show();
return 0;
}
if (rowsUpdated != 0) {
getContext().getContentResolver().notifyChange(uri, null);
}
return rowsUpdated;
}

private Uri insertProduct(Uri uri, ContentValues values) {
String name = values.getAsString(ProductContract.ProductEntry.COLUMN_PRODUCT_NAME);
if (name == null) {
throw new IllegalArgumentException("Enter the product name");
}
Integer quantity = values.getAsInteger(ProductContract.ProductEntry.COLUMN_PRODUCT_QUANTITY);
if (quantity != null && quantity < 0) {
throw new IllegalArgumentException("Enter the quantıty");
}
Integer price = values.getAsInteger(ProductContract.ProductEntry.COLUMN_PRODUCT_PRICE);

if (price != null && price < 0) {
throw new IllegalArgumentException("Product price should be valid");
}

SQLiteDatabase db = mdbHelper.getReadableDatabase();
long id = db.insert(ProductContract.ProductEntry.TABLE_NAME, null, values);
if (id == -1) {
Toast.makeText(getContext(), "Insert ıs not sucssesful", Toast.LENGTH_SHORT).show();
return null;
}

getContext().getContentResolver().notifyChange(uri, null);

return ContentUris.withAppendedId(uri, id);
}
}

Bu class ile insert,update,delete gibi işlemlerde yapmak istediğimiz işlemleri kodluyoruz. Bütün işlemlerin ayrı ayrı methodları vardır. İçeriğini kendi projemize göre revize edebiliriz.

Bir makalenin daha sonuna geldik, esenle kalın..