Question

我无法从SQLite数据库中检索存储为blob的图像。我正在使用Parcel。以下是我的代码。我想在imageView中显示名为galerie_foto_retrieve的图像。现在该应用程序显示错误。我无法运行它。我是android的初学者，所以你有任何想法，我做错了什么。我将不胜感激任何帮助！

的DataProvider

private byte[] byteArray;

public DataProvider(byte[] byteArray)

this.byteArray=byteArray;

protected DataProvider(Parcel in) 
{
byteArray = new byte[in.readInt()];
in.readByteArray(byteArray);
}

 @Override
public void writeToParcel(Parcel dest, int flags) 
{
dest.writeInt(byteArray.length);
dest.writeByteArray(byteArray);
}

DataListActivity

if (cursor.moveToFirst())
                {
                    do {byte[] byteArray;
                        byteArray = cursor.getBlob(210);
DataProvider dataProvider = new DataProvider(byteArray);
        }while (cursor.moveToNext());
                }
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
                @Override
                public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
                    Intent intent = new Intent(DataListActivity.this, RetrieveData.class);
                    intent.putExtra("data", (DataProvider) listDataAdapter.getItem(position));
                    startActivity(intent);
                }
            });

检索数据

byte[] byteArray;
    ImageView galerie_foto_retrieve;    

Bundle bundle = getIntent().getExtras();
            if (bundle!=null){
                DataProvider dataProvider = bundle.getParcelable("data");
    Bitmap b = BitmapFactory.decodeByteArray(byteArray , 0, byteArray.length);
                galerie_foto_retrieve.setImageBitmap(b);

DbOperace

public Cursor getInformations(SQLiteDatabase db)
    {
        Cursor cursor;
        String[] projections = {
FormDatabase.FormularovaDatabaze.IMAGE1
        };
        cursor = db.query(FormDatabase.FormularovaDatabaze.TABLE_NAME,projections,null,null,null,null,null);
        if (cursor != null) {
            cursor.moveToFirst();
            return cursor;
        }
        else
        {
            return cursor;
        }

Answer 1

我已经弄明白了！我的错误在于文件检索数据这是正确的解决方案，如果有人想知道

SELECT 
    pcr.PersonnelID, pcr.CourseID, lpc.CompletionDate
FROM 
    qryPersonnelCourseRequirements AS pcr 
LEFT JOIN 
    LnkPersonnelCourses AS lpc On 
    (pcr.CourseID = lpc.CourseID) AND (pcr.PersonnelID = lpc.PersonnelID );

Android-使用Parcelable从SQLite检索图像

1 个答案: