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PERSONS uriMatcher.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PERSON uriMatcher.addURI(AUTHORITY, "person/#", PERSON); } @Override public boolean onCreate() { dbOpenHelper = new DBOpenHelper(this.getContext()); return true; } @Override public 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id default: throw new IllegalArgumentException("Unknown URI " + uri); } } @Override public 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10 long personid = ContentUris.parseId(uri); String where = "id=" + personid;// 删除指定id的记录 where += !TextUtils.isEmpty(selection) " + 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; } @Override public 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10 long personid = ContentUris.parseId(uri); String where = "id=" + personid;// 获取指定id的记录 where += !TextUtils.isEmpty(selection) " + 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; } @Override public 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); } } @Override public 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10 long personid = ContentUris.parseId(uri); String where = "id=" + personid;// 获取指定id的记录 where += !TextUtils.isEmpty(selection) " + 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

<"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" /> <category android: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" /> <instrumentation android: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); } }

希望本文所述对大家Android程序设计有所帮助。