新建一个应用程序
<1>新建一个内容提供者类>
public class MyProvider extends ContentProvider{
private SQLiteDatabase sqLiteDatabase;
@Override
public boolean onCreate() {
Log.i("test","onCreate");
return false;
}
@Nullable
@Override
public Cursor query(@NonNull Uri uri, @Nullable String[] strings, @Nullable String s, @Nullable String[] strings1, @Nullable String s1) {
Log.i("test","query");
DBHelper dbHelper=new DBHelper(getContext(),"jiaokaobaodian.db",null,3);
sqLiteDatabase = dbHelper.getReadableDatabase();
return sqLiteDatabase.rawQuery("select * from jiaokaobaodian",null);
}
@Nullable
@Override
public String getType(@NonNull Uri uri) {
Log.i("test","getType");
return null;
}
@Nullable
@Override
public Uri insert(@NonNull Uri uri, @Nullable ContentValues contentValues) {
Log.i("test","insert");
return null;
}
@Override
public int delete(@NonNull Uri uri, @Nullable String s, @Nullable String[] strings) {
Log.i("test","delete");
return 0;
}
@Override
public int update(@NonNull Uri uri, @Nullable ContentValues contentValues, @Nullable String s, @Nullable String[] strings) {
Log.i("test","update");
return 0;
}
}
<二>配置
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.zking.y2_android16_sqlite">
<application android:allowBackup="true" android:icon="@mipmap/ic_launcher"
android:label="@string/app_name" android:roundIcon="@mipmap/ic_launcher_round"
android:supportsRtl="true" android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<provider
android:authorities="com.zking.y2_android16_sqlite.MY"
android:name="com.zking.provider.MyProvider"
android:exported="true"
android:enabled="true"
></provider>
</application>
</manifest>
<三>再新建一个程序,得到内容的访问者
public class MainActivity extends AppCompatActivity {
private ContentResolver contentResolver;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//得到内容访问者
contentResolver = getContentResolver();
}
public void query(View view){
//查询`
Uri uri=Uri.parse("content://com.zking.y2_android16_sqlite.MY");
Cursor cursor=contentResolver.query(uri,null,null,null,null);
while(cursor.moveToNext()){
int uid=cursor.getInt(cursor.getColumnIndex("uid"));
Log.i("test",""+uid);
}
}
}