Question

我正在获取图像路径URL，现在我想从该URL获取图像并保存到本地数据库但是我无法将其转换为字节，以便数据库中的BLOB将接受它。我已经尝试了很多，但都是徒劳的。我使用了代码，但是ByteArrayBuffer没有解析类型。

// code to convert image url into byte array

 private byte[] getLogoImage(String url) {
    try {
        URL imageUrl = new URL(url);
        URLConnection ucon = imageUrl.openConnection();
        System.out.println("11111");
        InputStream is = ucon.getInputStream();
        System.out.println("12121");

        BufferedInputStream bis = new BufferedInputStream(is);
        System.out.println("22222");

        ByteArrayBuffer baf = new ByteArrayBuffer(500);
        int current = 0;
        System.out.println("23333");

        while ((current = bis.read()) != -1) {
            baf.append((byte) current);

        }
        photo = baf.toByteArray();
        System.out.println("photo length" + photo);


    } catch (Exception e) {
        Log.d("ImageManager", "Error: " + e.toString());
    }
    return accImage;
}

之后我使用了教程＆＃34; https://github.com/CoderzHeaven/StoreImageSqliteAndroid＆＃34;保存到数据库

Answer 1

用这个替换你的方法

private byte[] getLogoImage(String url) {
try {
  URL imageUrl = new URL(url);
  URLConnection ucon = imageUrl.openConnection();
  System.out.println("11111");
  InputStream is = ucon.getInputStream();
  System.out.println("12121");

  byte[] buffer = new byte[8192];
  int bytesRead;
  ByteArrayOutputStream accImage = new ByteArrayOutputStream();
  while ((bytesRead = is.read(buffer)) != -1) {
    accImage.write(buffer, 0, bytesRead);
  }

  return accImage.toByteArray();

} catch (Exception e) {
  Log.d("ImageManager", "Error: " + e.toString());
}
return null;
}

Answer 2

**You can try this method for download and save image into database**

public class MainActivity extends Activity {
    protected SQLiteDatabase sqlitedatabase_obj;
    DataBaseHelper databasehlpr_obj;
    int accId;
    byte[] accImage;

    byte[] logoImage;
    byte[] photo;@Override

protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    AndroidContext.setContext(this);
    sqlitedatabase_obj = DataBaseHelper.getInstance().getDb();
    new ImageDownloader().execute("http://images.100bestbuy.com/images/small_137385013870957.jpg");
}
/* get logo image method */
private byte[] getLogoImage(String url) {
    try {
    URL imageUrl = new URL(url);
    URLConnection ucon = imageUrl.openConnection();
    System.out.println("test1");
    InputStream is = ucon.getInputStream();
    System.out.println("test2");

    BufferedInputStream bis = new BufferedInputStream(is);
    System.out.println("test3");

    ByteArrayBuffer baf = new ByteArrayBuffer(500);
    int current = 0;
    System.out.println("test4");

    while ((current = bis.read()) != -1) {
        baf.append((byte) current);

    }
    photo = baf.toByteArray();
    System.out.println("photo length" + photo);


} catch (Exception e) {
    Log.d("ImageManager", "Error: " + e.toString());
}
return accImage;
}

public void insertUser() {
    ContentValues userdetailValues = new ContentValues();
    userdetailValues.put("account_image", photo);
    sqlitedatabase_obj.insert(DataBaseHelper.IMG_table, null, userdetailValues);
}
/*  AsyncTask method */
private class ImageDownloader extends AsyncTask<String, Void, Void> {

    private ProgressDialog progressDialog;

    @Override
    protected Void doInBackground(String... param) {

         sqlitedatabase_obj.delete(DataBaseHelper.IMG_table, null, null);
         logoImage = getLogoImage(param[0]);

         insertUser();
    }

    @Override
    protected void onPreExecute() {

        progressDialog = ProgressDialog.show(MainActivity.this, "Wait", "Downloading Image");
    }

    @Override
    protected void onPostExecute(Void result) {
        progressDialog.dismiss();

    }

}

}

在Android应用中的本地数据库中存储和检索URL中的图像

2 个答案: