我有一个内容提供商存储一些数据（朋友的名字和他的生日日期）。我从here得到了这个例子。
然而，当我尝试添加这些数据时，我得到了这个例外！
E/AndroidRuntime: FATAL EXCEPTION: main
Process: theo.testing.friendsprovider, PID: 4363
java.lang.IllegalStateException: Could not execute method for android:onClick
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:293)
at android.view.View.performClick(View.java:4780)
at android.view.View$PerformClick.run(View.java:19866)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5254)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
Caused by: java.lang.reflect.InvocationTargetException
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:288)
at android.view.View.performClick(View.java:4780)
at android.view.View$PerformClick.run(View.java:19866)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5254)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
Caused by: java.lang.IllegalArgumentException: Unknown URL content://theo.testing.friendsprovider.BirthdayProv/friends
at android.content.ContentResolver.insert(ContentResolver.java:1203)
at theo.testing.friendsprovider.MainActivity.addBirthday(MainActivity.java:42)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at android.support.v7.app.AppCompatViewInflater$DeclaredOnClickListener.onClick(AppCompatViewInflater.java:288)
at android.view.View.performClick(View.java:4780)
at android.view.View$PerformClick.run(View.java:19866)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5254)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:903)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:698)
由于某些原因，我的Uri值无效。这是我的代码。
public class FriendsProvider extends ContentProvider {
//Fields for the content provider
static final String PROVIDER_NAME = "theo.testing.friendsprovider";
static final String URL = "content://" + PROVIDER_NAME + "/friends";
static final Uri CONTENT_URI = Uri.parse(URL);
//Field for the database
static final String ID = "id";
static final String NAME = "name";
static final String BIRTHDAY = "birthday";
//integer values used in content URI
static final int FRIENDS = 1;
static final int FRIENDS_ID = 2;
DBHelper dbHelper;
//Projections map for a query
private static HashMap<String,String> FriendsMap;
//Filling out the Uri matcher
static final UriMatcher uriMatcher;
static{
uriMatcher = new UriMatcher(UriMatcher.NO_MATCH);
uriMatcher.addURI(PROVIDER_NAME,"friends",FRIENDS);
uriMatcher.addURI(PROVIDER_NAME,"friends/#",FRIENDS_ID);
}
// database declarations
private SQLiteDatabase database;
static final String DATABASE_NAME = "BirthdayReminder";
static final String TABLE_NAME = "birthTable";
static final int DATABASE_VERSION = 1;
static final String CREATE_TABLE =
" CREATE TABLE " + TABLE_NAME +
" (id INTEGER PRIMARY KEY AUTOINCREMENT, " +
" name TEXT NOT NULL, " +
" birthday TEXT NOT NULL);";
public class DBHelper extends SQLiteOpenHelper {
static final String CREATE_TABLE =
" CREATE TABLE " + TABLE_NAME +
" (id INTEGER PRIMARY KEY AUTOINCREMENT, " +
" name TEXT NOT NULL, " +
" birthday TEXT NOT NULL);";
public DBHelper(Context context) {
super(context, DATABASE_NAME, null,DATABASE_VERSION);
}
@Override
public void onCreate(SQLiteDatabase sqLiteDatabase) {
sqLiteDatabase.execSQL(CREATE_TABLE);
}
@Override
public void onUpgrade(SQLiteDatabase sqLiteDatabase, int i, int i1) {
sqLiteDatabase.execSQL("DROP TABLE IF EXISTS " +TABLE_NAME);
}
}
@Override
public boolean onCreate() {
Context context = getContext();
dbHelper = new DBHelper(context);
//permissions to be writable
database = dbHelper.getWritableDatabase();
return false;
}
@Nullable
@Override
public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {
SQLiteQueryBuilder queryBuilder = new SQLiteQueryBuilder();
queryBuilder.setTables(TABLE_NAME);
switch (uriMatcher.match(uri)){
case FRIENDS:
queryBuilder.setProjectionMap(FriendsMap);
break;
case FRIENDS_ID:
queryBuilder.appendWhere(ID + "=" + uri.getLastPathSegment());
break;
default:
throw new IllegalArgumentException("Unkown URI:"+uri);
}
//sort name by default
if(sortOrder == null){
sortOrder = NAME;
}
Cursor cursor = queryBuilder.query(database,projection,selection,selectionArgs,null,null,sortOrder);
cursor.setNotificationUri(getContext().getContentResolver(),uri);
return null;
}
@Nullable
@Override
public String getType(Uri uri) {
switch (uriMatcher.match(uri)){
// Get all friend-birthday records
case FRIENDS:
return "vnd.android.cursor.dir/vnd.example.friends";
// Get a particular friend
case FRIENDS_ID:
return "vnd.android.cursor.item/vnd.example.friends";
default:
throw new IllegalArgumentException("Unsupported URI: " + uri);
}
}
@Nullable
@Override
public Uri insert(Uri uri, ContentValues contentValues) {
//Insertion of the table's data
long row = database.insert(TABLE_NAME,null,contentValues);
//If row was added successfully
if(row > 0){
Uri newUri = ContentUris.withAppendedId(CONTENT_URI,row);
getContext().getContentResolver().notifyChange(newUri,null);
}
//Else throw an exception.
throw new SQLException("Fail to add a new record into " + uri);
}
@Override
public int delete(Uri uri, String selection, String[] selectionArgs) {
// TODO Auto-generated method stub
int count = 0;
switch (uriMatcher.match(uri)){
case FRIENDS:
// delete all the records of the table
count = database.delete(TABLE_NAME, selection, selectionArgs);
break;
case FRIENDS_ID:
String id = uri.getLastPathSegment(); //gets the id
count = database.delete( TABLE_NAME, ID + " = " + id +
(!TextUtils.isEmpty(selection) ? " AND (" +
selection + ')' : ""), selectionArgs);
break;
default:
throw new IllegalArgumentException("Unsupported URI " + uri);
}
getContext().getContentResolver().notifyChange(uri, null);
return count;
}
@Override
public int update(Uri uri, ContentValues values, String selection,
String[] selectionArgs) {
// TODO Auto-generated method stub
int count = 0;
switch (uriMatcher.match(uri)){
case FRIENDS:
count = database.update(TABLE_NAME, values, selection, selectionArgs);
break;
case FRIENDS_ID:
count = database.update(TABLE_NAME, values, ID +
" = " + uri.getLastPathSegment() +
(!TextUtils.isEmpty(selection) ? " AND (" +
selection + ')' : ""), selectionArgs);
break;
default:
throw new IllegalArgumentException("Unsupported URI " + uri );
}
getContext().getContentResolver().notifyChange(uri, null);
return count;
}
}
MainActivity类
public class MainActivity extends AppCompatActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
public void deleteAllBirthdays(View view){
String URL = "theo.testing.friendsprovider";
Uri friends = Uri.parse(URL);
int count = getContentResolver().delete(
friends,null,null
);
String countNum = "My Friends: " + count + " records are deleted";
Toast.makeText(getBaseContext(),count,Toast.LENGTH_SHORT).show();
}
public void addBirthday(View view){
ContentValues values = new ContentValues();
values.put(FriendsProvider.NAME,
((EditText)findViewById(R.id.name)).getText().toString());
values.put(FriendsProvider.BIRTHDAY,
((EditText)findViewById(R.id.birthday)).getText().toString());
Uri uri = getContentResolver().insert(FriendsProvider.CONTENT_URI,values);
Toast.makeText(getBaseContext(),"My friend: " +uri.toString() + " inserted",Toast.LENGTH_SHORT).show();
}
public void showAllBirthdays(View view){
String URL = "theo.testing.friendsprovider";
Uri friends = Uri.parse(URL);
Cursor c = getContentResolver().query(friends,null,null,null,"name");
String results = "My friends:";
if (!c.moveToFirst()) {
Toast.makeText(this, results+" no content yet!", Toast.LENGTH_LONG).show();
}else{
do{
results = results + "\n" + c.getString(c.getColumnIndex(FriendsProvider.NAME)) +
" with id " + c.getString(c.getColumnIndex(FriendsProvider.ID)) +
" has birthday: " + c.getString(c.getColumnIndex(FriendsProvider.BIRTHDAY));
} while (c.moveToNext());
Toast.makeText(this, results, Toast.LENGTH_LONG).show();
}
}
}
这一行引发了我的异常。
Uri uri = getContentResolver().insert(FriendsProvider.CONTENT_URI,values);
最后这是我的 manifest.xml 文件。
<?xml version="1.0" encoding="utf-8"?>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
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>
</application>
<provider
android:name=".FriendProvider"
android:authorities="theo.testing.friendsprovider"
>
</provider>
如您所见，提供商已注册了权限及其名称。另外，我有所有陈述的变量。
static final String PROVIDER_NAME = "theo.testing.friendsprovider";
static final String URL = "content://" + PROVIDER_NAME + "/friends";
static final Uri CONTENT_URI = Uri.parse(URL);
有什么想法吗？
提前致谢，
西奥
答案 0 :(得分：2)
在应用标记
中添加提供者标记<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
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:name=".FriendProvider"
android:authorities="theo.testing.friendsprovider"
>
</provider>
</application>