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本文实例讲述了Android内容提供者ContentProvider用法。分享给大家供大家参考,具体如下:
PersonContentProvider内容提供者类
package com.ljq.db;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.text.TextUtils;/** * 内容提供者 ** 作用:统一数据访问方式,方便外部调用 ** @author jiqinlin **/public class PersonContentProvider extends ContentProvider {// 数据集的MIME类型字符串则应该以vnd.android.cursor.dir/开头public static final String PERSONS_TYPE = "vnd.android.cursor.dir/person";// 单一数据的MIME类型字符串应该以vnd.android.cursor.item/开头public static final String PERSONS_ITEM_TYPE = "vnd.android.cursor.item/person";public static final String AUTHORITY = "com.ljq.provider.personprovider";// 主机名/* 自定义匹配码 */public static final int PERSONS = 1;/* 自定义匹配码 */public static final int PERSON = 2;public static final Uri PERSONS_URI = Uri.parse("content://" + AUTHORITY + "/person");private DBOpenHelper dbOpenHelper = null;// UriMatcher类用来匹配Uri,使用match()方法匹配路径时返回匹配码private static final UriMatcher uriMatcher;static {// 常量UriMatcher.NO_MATCH表示不匹配任何路径的返回码uriMatcher = new UriMatcher(UriMatcher.NO_MATCH);// 如果match()方法匹配content://com.ljq.provider.personprovider/person路径,返回匹配码为PERSONSuriMatcher.addURI(AUTHORITY, "person", PERSONS);// 如果match()方法匹配content://com.ljq.provider.personprovider/person/230路径,返回匹配码为PERSONuriMatcher.addURI(AUTHORITY, "person/#", PERSON);}@Overridepublic boolean onCreate() {dbOpenHelper = new DBOpenHelper(this.getContext());return true;}@Overridepublic Uri insert(Uri uri, ContentValues values){SQLiteDatabase db = dbOpenHelper.getWritableDatabase();long id = 0;switch (uriMatcher.match(uri)) {case PERSONS:id = db.insert("person", "name", values);// 返回的是记录的行号,主键为int,实际上就是主键值return ContentUris.withAppendedId(uri, id);case PERSON:id = db.insert("person", "name", values);String path = uri.toString();return Uri.parse(path.substring(0, path.lastIndexOf("/"))+id); // 替换掉iddefault:throw new IllegalArgumentException("Unknown URI " + uri);}}@Overridepublic int delete(Uri uri, String selection, String[] selectionArgs) {SQLiteDatabase db = dbOpenHelper.getWritableDatabase();int count = 0;switch (uriMatcher.match(uri)) {case PERSONS:count = db.delete("person", selection, selectionArgs);break;case PERSON:// 下面的方法用于从URI中解析出id,对这样的路径content://com.ljq.provider.personprovider/person/10// 进行解析,返回值为10long personid = ContentUris.parseId(uri);String where = "id=" + personid;// 删除指定id的记录where += !TextUtils.isEmpty(selection) ? " and (" + selection + ")" : "";// 把其它条件附加上count = db.delete("person", where, selectionArgs);break;default:throw new IllegalArgumentException("Unknown URI " + uri);}db.close();return count;}@Overridepublic int update(Uri uri, ContentValues values, String selection,String[] selectionArgs) {SQLiteDatabase db = dbOpenHelper.getWritableDatabase();int count = 0;switch (uriMatcher.match(uri)) {case PERSONS:count = db.update("person", values, selection, selectionArgs);break;case PERSON:// 下面的方法用于从URI中解析出id,对这样的路径content://com.ljq.provider.personprovider/person/10// 进行解析,返回值为10long personid = ContentUris.parseId(uri);String where = "id=" + personid;// 获取指定id的记录where += !TextUtils.isEmpty(selection) ? " and (" + selection + ")" : "";// 把其它条件附加上count = db.update("person", values, where, selectionArgs);break;default:throw new IllegalArgumentException("Unknown URI " + uri);}db.close();return count;}@Overridepublic String getType(Uri uri) {switch (uriMatcher.match(uri)) {case PERSONS:return PERSONS_TYPE;case PERSON:return PERSONS_ITEM_TYPE;default:throw new IllegalArgumentException("Unknown URI " + uri);}}@Overridepublic Cursor query(Uri uri, String[] projection, String selection,String[] selectionArgs, String sortOrder) {SQLiteDatabase db = dbOpenHelper.getReadableDatabase();switch (uriMatcher.match(uri)) {case PERSONS:return db.query("person", projection, selection, selectionArgs, null, null, sortOrder);case PERSON:// 下面的方法用于从URI中解析出id,对这样的路径content://com.ljq.provider.personprovider/person/10// 进行解析,返回值为10long personid = ContentUris.parseId(uri);String where = "id=" + personid;// 获取指定id的记录where += !TextUtils.isEmpty(selection) ? " and (" + selection + ")" : "";// 把其它条件附加上return db.query("person", projection, where, selectionArgs, null, null, sortOrder);default:throw new IllegalArgumentException("Unknown URI " + uri);}}}
文件清单
<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android"package="com.ljq.sql" android:versionCode="1"android:versionName="1.0"><application android:icon="@drawable/icon"android:label="@string/app_name"><uses-library android:name="android.test.runner" /><activity android:name=".SqlActivity"android:label="@string/app_name"><intent-filter><action android:name="android.intent.action.MAIN" /><categoryandroid:name="android.intent.category.LAUNCHER" /></intent-filter></activity><provider android:name="com.ljq.db.PersonContentProvider"android:authorities="com.ljq.provider.personprovider" /></application><uses-sdk android:minSdkVersion="7" /><instrumentationandroid:name="android.test.InstrumentationTestRunner"android:targetPackage="com.ljq.sql" android:label="Tests for My App" /></manifest>
PersonContentProviderTest内容提供者测试类
package com.ljq.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;/** * 外部访问内容提供者 ** @author jiqinlin * */public class PersonContentProviderTest extends AndroidTestCase{private static final String TAG = "PersonContentProviderTest";public void testSave() throws Throwable{ContentResolver contentResolver = this.getContext().getContentResolver();Uri insertUri = Uri.parse("content://com.ljq.provider.personprovider/person");ContentValues values = new ContentValues();values.put("name", "ljq");values.put("phone", "1350000009");Uri uri = contentResolver.insert(insertUri, values);Log.i(TAG, uri.toString());}public void testUpdate() throws Throwable{ContentResolver contentResolver = this.getContext().getContentResolver();Uri updateUri = Uri.parse("content://com.ljq.provider.personprovider/person/1");ContentValues values = new ContentValues();values.put("name", "linjiqin");contentResolver.update(updateUri, values, null, null);}public void testFind() throws Throwable{ContentResolver contentResolver = this.getContext().getContentResolver();//Uri uri = Uri.parse("content://com.ljq.provider.personprovider/person");Uri uri = Uri.parse("content://com.ljq.provider.personprovider/person");Cursor cursor = contentResolver.query(uri, null, null, null, "id asc");while(cursor.moveToNext()){int personid = cursor.getInt(cursor.getColumnIndex("id"));String name = cursor.getString(cursor.getColumnIndex("name"));String phone = cursor.getString(cursor.getColumnIndex("phone"));Log.i(TAG, "personid="+ personid + ",name="+ name+ ",phone="+ phone);}cursor.close();}public void testDelete() throws Throwable{ContentResolver contentResolver = this.getContext().getContentResolver();Uri uri = Uri.parse("content://com.ljq.provider.personprovider/person/1");contentResolver.delete(uri, null, null);}}
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