Question

我正在尝试将我的图像保存到SQLite数据库，并且现在已经挣扎了一段时间。因此，经过几周的研究，我终于决定检查图像是否实际添加到数据库而不是。我设法显示我的数据库，可以看到lat和lng点以及缩放级别保存到数据库但不保存到图像（它在“blob”字段中为null）

所以这就是我所拥有的：

对于我的数据库，我有这个：

public class LocationsDB extends SQLiteOpenHelper{
private static String DBNAME = "locationmarkersqlite";
private static int VERSION = 1;
public static final String FIELD_ROW_ID = "_id";
public static final String FIELD_LAT = "lat";
public static final String FIELD_LNG = "lng";
public static final String FIELD_ZOOM = "zom";
public static final String FIELD_IMAGE = "blob";
private static final String DATABASE_TABLE = "locations";

private SQLiteDatabase mDB;

public LocationsDB(Context context) {
    super(context, DBNAME, null, VERSION);
    this.mDB = getWritableDatabase();
}

@Override
public void onCreate(SQLiteDatabase db) {
    String sql =     "create table " + DATABASE_TABLE + " ( " +
                     FIELD_ROW_ID + " integer primary key autoincrement , " +
                     FIELD_LNG + " double , " +
                     FIELD_LAT + " double , " +
                     FIELD_ZOOM + " text , " +
                     FIELD_IMAGE + " blob " +
                     " ) ";

    db.execSQL(sql);
}

public long insert(ContentValues contentValues){
    long rowID = mDB.insert(DATABASE_TABLE, null, contentValues);
    return rowID;
}

public int del(){
    int cnt = mDB.delete(DATABASE_TABLE, null , null);
    return cnt;
}

public Cursor getAllLocations(){
    return mDB.query(DATABASE_TABLE, new String[] { FIELD_ROW_ID,  FIELD_LAT , FIELD_LNG, FIELD_ZOOM, FIELD_IMAGE} , null, null, null, null, null, null);
}

@Override
public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
}

public static Cursor rawQuery(String string, Object object) {
    // TODO Auto-generated method stub
    return null;
}

然后在我的LocationsContentProvider课程中我有这个：

public class LocationsContentProvider extends ContentProvider{

public static final String PROVIDER_NAME = "com.test.markertest.locations";
public static final Uri CONTENT_URI = Uri.parse("content://" + PROVIDER_NAME + "/locations" );
private static final int LOCATIONS = 1;
private static final UriMatcher uriMatcher ;

static {
    uriMatcher = new UriMatcher(UriMatcher.NO_MATCH);
    uriMatcher.addURI(PROVIDER_NAME, "locations", LOCATIONS);
}

LocationsDB mLocationsDB;

@Override
public boolean onCreate() {
    mLocationsDB = new LocationsDB(getContext());
    return true;
}

@Override
public Uri insert(Uri uri, ContentValues values) {
    long rowID = mLocationsDB.insert(values);
    Uri _uri=null;
    if(rowID>0){
        _uri = ContentUris.withAppendedId(CONTENT_URI, rowID);
    }else {
        try {
            throw new SQLException("Failed to insert : " + uri);
        } catch (SQLException e) {
            e.printStackTrace();
        }
    }
    return _uri;
}

@Override
public int update(Uri uri, ContentValues values, String selection,
    String[] selectionArgs) {
    return 0;
}
@Override
public int delete(Uri uri, String selection, String[] selectionArgs) {
    int cnt = 0;
    cnt = mLocationsDB.del();
    return cnt;
}
@Override
public Cursor query(Uri uri, String[] projection, String selection, String[] selectionArgs, String sortOrder) {

    if(uriMatcher.match(uri)==LOCATIONS){
        return mLocationsDB.getAllLocations();
    }
    return null;
}

@Override
public String getType(Uri uri) {
    return null;
}

最后在我的MainActivity课程中我完成了这个：

@Override
public void onMapLongClick(LatLng point) {
    thePoint=point;

    drawMarker(point);
    contentValues.put(LocationsDB.FIELD_LAT, point.latitude);
    contentValues.put(LocationsDB.FIELD_LNG, point.longitude);
    contentValues.put(LocationsDB.FIELD_ZOOM, googleMap.getCameraPosition().zoom);
    LocationInsertTask insertTask = new LocationInsertTask();
    insertTask.execute(contentValues);

     Intent imageIntent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
     timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss").format(new Date());
     File imagesFolder = new File(Environment.getExternalStorageDirectory(), "My Images");
     imagesFolder.mkdirs();
     image = new File(imagesFolder.getPath(), "Myimage_" + timeStamp + ".jpg");
     fileUri = Uri.fromFile(image);

     imageIntent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);
     startActivityForResult(imageIntent, TAKE_PICTURE);
}

  private void drawMarker(LatLng point) {
    Marker marker = googleMap.addMarker(new MarkerOptions()
    .position(thePoint));
    markerId = marker.getId();

}

public void onActivityResult(int requestCode, int resultCode, Intent data) {
      if (requestCode == TAKE_PICTURE && resultCode == RESULT_OK) {
              try {
                  GetImageThumbnail getImageThumbnail = new GetImageThumbnail();
                  bitmap = getImageThumbnail.getThumbnail(fileUri, this);

              } catch (FileNotFoundException e1) {
                  e1.printStackTrace();
              } catch (IOException e1) {
                  e1.printStackTrace();
              }
         ExifInterface exif = null;

        try {
            exif = new ExifInterface(image.getAbsolutePath());
        } catch (IOException e) {
            e.printStackTrace();
        }
           int orientation = exif.getAttributeInt(ExifInterface.TAG_ORIENTATION, -1);
           if (orientation != -1) {
                   switch (orientation) {
                   case ExifInterface.ORIENTATION_ROTATE_90:
                       rotate = 90;
                       break;
                   case ExifInterface.ORIENTATION_ROTATE_180:
                       rotate = 180;
                       break;
                   case ExifInterface.ORIENTATION_ROTATE_270:
                       rotate = 270;
                       break;
                   default:
                       rotate = 0;
                       break;
                   }
           }
           Matrix matrix = new Matrix();
            matrix.postRotate(rotate);
            bitmap = Bitmap.createBitmap(bitmap, 0, 0, bitmap.getWidth(), bitmap.getHeight(), matrix, false);
           baos = new ByteArrayOutputStream();
           bitmap.compress(CompressFormat.PNG, 100, baos);
           imageData = baos.toByteArray();
           myMarkersHash.put(markerId, bitmap);
           contentValues.put(LocationsDB.FIELD_IMAGE, markerId + imageData);
           }
        }

所以我试过将此contentValues.put(LocationsDB.FIELD_IMAGE, markerId + imageData);更改为此contentValues.put(LocationsDB.FIELD_IMAGE, imageData); 但仍然没有运气。数据库仍然在FIELD_IMAGE列中说明null

有谁能告诉我我做错了什么？感谢

Answer 1

LocationInsertTask在图像捕获活动开始之前开始执行，因此blob数据被放入ContentValues方式太晚了。

在获得活动结果后运行插入。

图像数据未保存到SQLite数据库

1 个答案: