ContentProvider 实例

这个实例是建立在上一个sqlite数据库上的, sqlite中提供ContentProvider, Other项目写测试方法来访问:

需要注意的是, ContentProvider需要在AndroidMainifest.xml 中注册:

package com.xiaoming.sqlite;import java.util.regex.Matcher;import com.xiaoming.domain.DBOpenHelper;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;public class PersonsProvider extends ContentProvider {DBOpenHelper  dbOpenHelper = null;public static final String     AUTHORITIES =  "com.xiaoming.sqlite.provicer";public static final UriMatcher Matcher = new UriMatcher(UriMatcher.NO_MATCH);public static final int        PERSONS =  1;public static final int        PERSON =  2;static {Matcher.addURI(AUTHORITIES, "persons",PERSONS );Matcher.addURI(AUTHORITIES, "persons/#",PERSON ); //#代表数字, *代表所有字符}@Overridepublic boolean onCreate() {dbOpenHelper = new DBOpenHelper(this.getContext());return true;}@Overridepublic Cursor query(Uri uri, String[] projection, String selection,String[] selectionArgs, String sortOrder) {SQLiteDatabase db = dbOpenHelper.getReadableDatabase();switch (Matcher.match(uri)) {case 1:return db.query("persons", projection, selection, selectionArgs, null, null, sortOrder);case 2:long rowid = ContentUris.parseId(uri);String where = "_id="+rowid;if( selection != null && !"".equals(selection)){where += " and "+selection;}return db.query("persons", projection, where, selectionArgs, null, null, sortOrder);default:throw new IllegalArgumentException("this is a unknow uri:"+uri);}}@Overridepublic String getType(Uri uri) {// TODO Auto-generated method stubreturn null;}@Overridepublic Uri insert(Uri uri, ContentValues values) {SQLiteDatabase db = dbOpenHelper.getWritableDatabase();switch (Matcher.match(uri)) {case 1:long rowid = db.insert("persons", "name", values);Uri insertUri = Uri.parse(AUTHORITIES+"/persons/"+rowid);//Uri insertUri = ContentUris.withAppendedId(uri, rowid);return insertUri;default:throw new IllegalArgumentException("this is Unknown Uri:"+uri);}}@Overridepublic int delete(Uri uri, String selection, String[] selectionArgs) {SQLiteDatabase db = dbOpenHelper.getWritableDatabase();int num = 0;switch (Matcher.match(uri)) {case 1:num = db.delete("persons", selection, selectionArgs);break;case 2:long rowid = ContentUris.parseId(uri);String where = "_id="+rowid;if( selection!=null && !"".equals(selection.trim()) ){where += " and " + selection;}num = db.delete("persons", where, selectionArgs);break;default:throw new IllegalArgumentException("this is Unknown Uri:"+uri);}return num;}@Overridepublic int update(Uri uri, ContentValues values, String selection,String[] selectionArgs) {SQLiteDatabase db = dbOpenHelper.getWritableDatabase();int num = 0;switch (Matcher.match(uri)) {case 1:num = db.update("persons", values, selection, selectionArgs);break;case 2:long rowid = ContentUris.parseId(uri);String where = "_id="+rowid;if( selection!=null && !"".equals(selection.trim()) ){where += " and " + selection;}num = db.update("persons", values, where, selectionArgs);break;default:throw new IllegalArgumentException("this is Unknown Uri:"+uri);}return num;}}

Other项目中的测试代码:

package com.xiaoming.other.test;import android.content.ContentResolver;import android.content.ContentValues;import android.database.Cursor;import android.net.Uri;import android.test.AndroidTestCase;import android.util.Log;public class ContentProviderTest extends AndroidTestCase {private static final String TAG = "ContentProviderTest";public void testContentProvicerTest() throws Exception{Uri uri = Uri.parse("content://com.xiaoming.sqlite.provicer/persons");ContentResolver resolver = this.getContext().getContentResolver();ContentValues values = new ContentValues();values.put("name", "android");values.put("age", 1000);resolver.insert(uri, values);}public void testDelete() throws Exception{Uri uri = Uri.parse("content://com.xiaoming.sqlite.provicer/persons/7");ContentResolver resolver = this.getContext().getContentResolver();resolver.delete(uri, null , null);}public void testUpdate() throws Exception{Uri uri = Uri.parse("content://com.xiaoming.sqlite.provicer/persons/9");ContentValues values = new ContentValues();values.put("name", "小黄");ContentResolver resolver = this.getContext().getContentResolver();resolver.update(uri, values, null, null);}public void testQuery() throws Exception{Uri uri = Uri.parse("content://com.xiaoming.sqlite.provicer/persons");ContentResolver resolver = this.getContext().getContentResolver();Cursor  result = resolver.query(uri, null, null, null, null);while( result.moveToNext() ){Log.i(TAG,result.getString(result.getColumnIndex("name") ));}}}