我尝试通过方法
将保存功能添加到我的笔记应用中 public boolean saveNote()
{
String title=mTitleEditText.getText().toString();
if(TextUtils.isEmpty(title))
{
mTitleEditText.setError("Title is required");
return false;
}
String content=mContentEditText.getText().toString();
if(TextUtils.isEmpty(content))
{
mContentEditText.setError("Content is required");
return false;
}
Log.e(TAG,"Creating new Note");
Note note = new Note();
note.setTitle(title);
note.setContent(content);
NoteManager.newInstance(getActivity()).create(note);
return true;
}
在NoteManager类中，我有创建方法 -
public long create(Note note) {
ContentValues values = new ContentValues();
values.put(Constants.COLUMN_TITLE, note.getTitle());
values.put(Constants.COLUMN_CONTENT, note.getContent());
values.put(Constants.COLUMN_CREATED_TIME, System.currentTimeMillis());
values.put(Constants.COLUMN_MODIFIED_TIME, System.currentTimeMillis());
Uri result = mContext.getContentResolver().insert(NoteContentProvider.CONTENT_URI, values); // line 39 in LOGCAT
long id = Long.parseLong(result.getLastPathSegment());
return id;
}
当我尝试保存并创建新笔记时出现以下错误
java.lang.IllegalArgumentException: Unknown URL content:/com.example.android.sqlitedbase.data.NoteContentProvider/notes
at android.content.ContentResolver.insert(ContentResolver.java:862)
at com.example.android.sqlitedbase.data.NoteManager.create(NoteManager.java:39)
at com.example.android.sqlitedbase.fragments.NoteLinedEditorFragment.saveNote(NoteLinedEditorFragment.java:169)
我的DataBaseHelper类
public class DatabaseHelper extends SQLiteOpenHelper{
private static final String DATABASE_NAME = "simple_note_app.db";
private static final int DATABASE_VERSION = 1;
public DatabaseHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase db) {
db.execSQL(CREATE_TABLE_NOTE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
db.execSQL("DROP TABLE IF EXISTS " + Constants.NOTES_TABLE);
onCreate(db);
}
private static final String CREATE_TABLE_NOTE = "create table "
+ Constants.NOTES_TABLE
+ "("
+ Constants.COLUMN_ID + " integer primary key autoincrement, "
+ Constants.COLUMN_TITLE + " text not null, "
+ Constants.COLUMN_CONTENT + " text not null, "
+ Constants.COLUMN_MODIFIED_TIME + " integer not null, "
+ Constants.COLUMN_CREATED_TIME + " integer not null " + ")";
}
NoteContentProvider
public class NoteContentProvider extends ContentProvider {
private DatabaseHelper dbHelper;
private static final String TAG="adf";
private static final String BASE_PATH_NOTE = "notes";
private static final String AUTHORITY = "com.example.android.sqlitedbase.data.NoteContentProvider";
// public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY + "/" + BASE_PATH_NOTE);
public static final Uri CONTENT_URI = Uri.parse("content:/" + AUTHORITY + "/" + BASE_PATH_NOTE);
private static final int NOTE = 100;
private static final int NOTES = 101;
private static final UriMatcher URI_MATCHER = new UriMatcher(UriMatcher.NO_MATCH);
static {
URI_MATCHER.addURI(AUTHORITY, BASE_PATH_NOTE, NOTES);
URI_MATCHER.addURI(AUTHORITY, BASE_PATH_NOTE + "/#", NOTE);
}
private void checkColumns(String[] projection) {
if (projection != null) {
HashSet<String> request = new HashSet<String>(Arrays.asList(projection));
HashSet<String> available = new HashSet<String>(Arrays.asList(Constants.COLUMNS));
if (!available.containsAll(request)) {
throw new IllegalArgumentException("Unknown columns in projection");
}
}
}
@Override
public boolean onCreate() {
dbHelper = new DatabaseHelper(getContext());
return false;
}
@Override
public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
SQLiteQueryBuilder queryBuilder = new SQLiteQueryBuilder();
checkColumns(projection);
int type = URI_MATCHER.match(uri);
switch (type){
case NOTE:
//there is not to do if the query is for the table
break;
case NOTES:
queryBuilder.appendWhere(Constants.COLUMN_ID + " = " + uri.getLastPathSegment());
break;
default:
throw new IllegalArgumentException("Unknown URI: " + uri);
}
SQLiteDatabase db = dbHelper.getWritableDatabase();
Cursor cursor = queryBuilder.query(db, projection, selection, selectionArgs, null, null, sortOrder);
cursor.setNotificationUri(getContext().getContentResolver(), uri);
return cursor;
}
@Override
public String getType(Uri uri) {
return null;
}
@Override
public Uri insert(Uri uri, ContentValues values) {
int type = URI_MATCHER.match(uri);
Log.e(TAG,"The uri type is "+type);
SQLiteDatabase db = dbHelper.getWritableDatabase();
Long id;
switch (type){
case NOTES:
id = db.insert(Constants.NOTES_TABLE, null, values);
break;
default:
throw new IllegalArgumentException("Unknown URI: " + uri);
}
getContext().getContentResolver().notifyChange(uri, null);
return Uri.parse(BASE_PATH_NOTE + "/" + id);
}
@Override
public int delete(Uri uri, String selection, String[] selectionArgs) {
int type = URI_MATCHER.match(uri);
SQLiteDatabase db = dbHelper.getWritableDatabase();
int affectedRows;
switch (type) {
case NOTES:
affectedRows = db.delete(Constants.NOTES_TABLE, selection, selectionArgs);
break;
case NOTE:
String id = uri.getLastPathSegment();
if (TextUtils.isEmpty(selection)) {
affectedRows = db.delete(Constants.NOTES_TABLE, Constants.COLUMN_ID + "=" + id, null);
} else {
affectedRows = db.delete(Constants.NOTES_TABLE, Constants.COLUMN_ID + "=" + id + " and " + selection, selectionArgs);
}
break;
default:
throw new IllegalArgumentException("Unknown URI: " + uri);
}
getContext().getContentResolver().notifyChange(uri, null);
return affectedRows;
}
@Override
public int update(Uri uri, ContentValues values, String selection, String[] selectionArgs) {
int type = URI_MATCHER.match(uri);
SQLiteDatabase db = dbHelper.getWritableDatabase();
int affectedRows;
switch (type) {
case NOTES:
affectedRows = db.update(Constants.NOTES_TABLE, values, selection, selectionArgs);
break;
case NOTE:
String id = uri.getLastPathSegment();
if (TextUtils.isEmpty(selection)) {
affectedRows = db.update(Constants.NOTES_TABLE, values, Constants.COLUMN_ID + "=" + id, null);
} else {
affectedRows = db.update(Constants.NOTES_TABLE, values, Constants.COLUMN_ID + "=" + id + " and " + selection, selectionArgs);
}
break;
default:
throw new IllegalArgumentException("Unknown URI: " + uri);
}
getContext().getContentResolver().notifyChange(uri, null);
return affectedRows;
}
}
清单文件
<manifest package="com.example.android.sqlitedbase"
xmlns:android="http://schemas.android.com/apk/res/android">
<permission android:name="READ_EXTERNAL_STORAGE"/>
<permission android:name="WRITE_EXTERNAL_STORAGE"/>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".activities.MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN"/>
<category android:name="android.intent.category.LAUNCHER"/>
</intent-filter>
</activity>
<activity android:name=".activities.NoteEditorActivity">
</activity>
<provider
android:authorities="com.example.android.sqlitedbase.data.NoteContentProvider"
android:exported="false"
android:name=".data.NoteContentProvider" >
</provider>
</application>
</manifest>
答案 0 :(得分：0)
你的清单应该是这样的：
<provider
android:authorities="com.example.android.sqlitedbase.data.NoteContentProvider"
android:name=".data.NoteContentProvider"
android:exported="false"/>
如果它看起来像这样但仍然不起作用，请将权限更改为＆＃34; com.example.android.provider＆＃34;清单和内容提供者。当局不必是提供者的类名。