我是全新的，我确信我以某种方式搞砸了代码，请帮我解决。
我有以下contentprovider用于构建数据库来存储收藏的标签：
public class FTagsContentProvider extends ContentProvider {
static final String AUTHORITY = "ch.ethz.twimight.FTags";
private static final String BASE_PATH = "ftags";
public static final Uri CONTENT_URI = Uri.parse("content://" + AUTHORITY
+ "/" + BASE_PATH);
// fields for the database
public static final String COL_ID = "id";
public static final String COL_TEXT = "text";
public static final String COL_COUNT = "count";
static final int FTAGS = 1;
static final int FTAGS_ID = 2;
DBHelper dbHelper;
private static HashMap<String, String> FTagsMap;
static final UriMatcher uriMatcher;
static{
uriMatcher = new UriMatcher(UriMatcher.NO_MATCH);
uriMatcher.addURI(AUTHORITY, BASE_PATH, FTAGS);
uriMatcher.addURI(AUTHORITY, BASE_PATH + "/#", FTAGS_ID);
}
// database declarations
private SQLiteDatabase database;
static final String DATABASE_NAME = "ftagtable.db";
static final String TABLE_FTAGS = "FTags";
static final int DATABASE_VERSION = 1;
private static final String TABLE_FTAGS_CREATE = "create table "
+ TABLE_FTAGS
+ "("
+ COL_ID + " integer primary key autoincrement, "
+ COL_TEXT + " text not null, "
+ COL_COUNT + " integer"
+ ");";
private static class DBHelper extends SQLiteOpenHelper {
public DBHelper(Context context) {
super(context, DATABASE_NAME, null, DATABASE_VERSION);
// TODO Auto-generated constructor stub
}
@Override
public void onCreate(SQLiteDatabase db) {
// TODO Auto-generated method stub
db.execSQL(TABLE_FTAGS_CREATE);
}
@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
// TODO Auto-generated method stub
Log.w(DBHelper.class.getName(),
"Upgrading database from version " + oldVersion + " to "
+ newVersion + ". Old data will be destroyed");
db.execSQL("DROP TABLE IF EXISTS " + TABLE_FTAGS);
onCreate(db);
}
}
@Override
public boolean onCreate() {
// TODO Auto-generated method stub
Context context = getContext();
dbHelper = new DBHelper(context);
database = dbHelper.getWritableDatabase();
if(database == null)
return false;
else
return true;
}
@Override
public Cursor query(Uri uri, String[] projection, String selection,
String[] selectionArgs, String sortOrder) {
// TODO Auto-generated method stub
SQLiteQueryBuilder queryBuilder = new SQLiteQueryBuilder();
queryBuilder.setTables(TABLE_FTAGS);
switch (uriMatcher.match(uri)) {
case FTAGS:
queryBuilder.setProjectionMap(FTagsMap);
break;
case FTAGS_ID:
queryBuilder.appendWhere( COL_ID + "=" + uri.getLastPathSegment());
break;
default:
throw new IllegalArgumentException("Unknown URI " + uri);
}
if (sortOrder == null || sortOrder == ""){
sortOrder = COL_TEXT;
}
Cursor cursor = queryBuilder.query(database, projection, selection,
selectionArgs, null, null, sortOrder);
/**
* register to watch a content URI for changes
*/
cursor.setNotificationUri(getContext().getContentResolver(), uri);
return cursor;
}
@Override
public Uri insert(Uri uri, ContentValues values) {
// TODO Auto-generated method stub
long row = database.insert(TABLE_FTAGS, "", values);
if(row > 0) {
Uri newUri = ContentUris.withAppendedId(CONTENT_URI, row);
getContext().getContentResolver().notifyChange(newUri, null);
return newUri;
}
throw new SQLException("Fail to add a new record into " + uri);
}
@Override
public int update(Uri uri, ContentValues values, String selection,
String[] selectionArgs) {
// TODO Auto-generated method stub
int rowsUpdated = 0;
switch (uriMatcher.match(uri)){
case FTAGS:
rowsUpdated = database.update(TABLE_FTAGS, values, selection, selectionArgs);
break;
case FTAGS_ID:
rowsUpdated = database.update(TABLE_FTAGS, values, COL_ID +
" = " + uri.getLastPathSegment() +
(!TextUtils.isEmpty(selection) ? " AND (" +
selection + ')' : ""), selectionArgs);
break;
default:
throw new IllegalArgumentException("Unsupported URI " + uri );
}
getContext().getContentResolver().notifyChange(uri, null);
return rowsUpdated;
}
@Override
public int delete(Uri uri, String selection, String[] selectionArgs) {
// TODO Auto-generated method stub
int count = 0;
switch (uriMatcher.match(uri)){
case FTAGS:
count = database.delete(TABLE_FTAGS, selection, selectionArgs);
break;
case FTAGS_ID:
String id = uri.getLastPathSegment(); //gets the id
count = database.delete( TABLE_FTAGS, COL_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 String getType(Uri uri) {
// TODO Auto-generated method stub
return null;
}
}
我想将COL_COUNT设置为保持计数标签插入数据库的次数的值，最初每个标签应该为1，我希望它只更新计数，如1到2每次输入现有标签时都是如此。
这是活动：
public class TestActivity extends Activity {
private EditText mText;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.test);
}
public boolean check(String s){
boolean t = false;
ContentResolver contentResolver = this.getContentResolver();
Cursor cursor = contentResolver.query(FTagsContentProvider.CONTENT_URI,
new String []{FTagsContentProvider.COL_TEXT}, FTagsContentProvider.COL_TEXT + "=?", new String[]{s}, null);
if(cursor.getCount > 0){
t = true;
}
else{
t = false;
}
cursor.close();
return t;
}
public void addFTag(View view) {
// Add a new tag
ContentValues values = new ContentValues();
mText = (EditText)findViewById(R.id.name);
String mFtag = mText.getText().toString();
boolean exist = check(mFtag);
if(exist == false){
values.put(FTagsContentProvider.COL_TEXT,
mFtag);
Uri uri = getContentResolver().insert(
FTagsContentProvider.CONTENT_URI, values);
Toast.makeText(getBaseContext(),
"Record inserted!", Toast.LENGTH_LONG).show();
}
else{
// code for only updating the COL_COUNT somehow
Toast.makeText(this, "Some tag meet you again :)",
Toast.LENGTH_LONG).show();
}}
public void showAllTags(View view) {
Cursor c = getContentResolver().query(FTagsContentProvider.CONTENT_URI, null, null, null, null);
String result = "Results:";
if (!c.moveToFirst()) {
Toast.makeText(this, result+" no content yet!", Toast.LENGTH_LONG).show();
}else{
do{
result = result + "\n" + c.getString(c.getColumnIndex(FTagsContentProvider.COL_TEXT)) +
" with id " + c.getString(c.getColumnIndex(FTagsContentProvider.COL_ID)) +
" has count: " + c.getString(c.getColumnIndex(FTagsContentProvider.COL_COUNT));
} while (c.moveToNext());
Toast.makeText(this, result, Toast.LENGTH_LONG).show();
}
}
}
非常感谢任何帮助：）