Develop Reference

Downloading and saving images from https URLs in android

I have this function that downloads and saves images in device -
public void DownloadFromUrl(String WebURL, String fileName) {
try {
URL url = new URL(WebURL);
file = new File(context.getFilesDir() + fileName+".jpg");
long startTime = System.currentTimeMillis();
URLConnection ucon = url.openConnection();
InputStream is = ucon.getInputStream();
BufferedInputStream bis = new BufferedInputStream(is);
ByteArrayBuffer baf = new ByteArrayBuffer(50);
int current = 0;
while ((current = bis.read()) != -1) {
baf.append((byte) current);
}
FileOutputStream fos = new FileOutputStream(file);
fos.write(baf.toByteArray());
fos.close();
} catch (IOException e) {
Log.d("ImageManager", "Error: " + e);
}
}
If I supply an https URL, it cannot save the image. Any pointers on how to download and save https images ?

I hope this link will help you. Uploading/Downloading Pictures by Tonikami.
https://www.youtube.com/playlist?list=PLe60o7ed8E-Q7tqKNPnWFdUoeniqH_-A9

Just use Picasso or Glide. It is super easy to use. And the best part is that it does automatic disk and memory caching, so you do not have to worry about anything.
Picasso - check out this link.
OR
Glide - check out this link.

The only mistake I made above is that I was trying to download and save large images when connectivity was slow. Some of my images are around 5-10 MB. Otherwise the code is fine.

How to download all images one by one and show progress status

I want to download all the images I have on server in the array string of Url one by one so that I may do not have to download a zip file of images from the server and to unzip after downloading it.
So I thought to download the images one by one and to show the download status in the progress bar. But I am extremely failed in it. An Idea came into my mind to make the string array of the Url and to use the For loop to download but it is downloading the last image of the String array and decline or pass all other images in the array . I think I have got the idea that what is going on but I have know Idea what would be the solution then.
What I have done So far
protected Void doInBackground(Void... arg0) {
try {
//set the download URL, a url that points to a file on the internet
//this is the file to be downloaded
String [] imageUrl = {"http://www.androidbegin.com/tutorial/flag/india.png","http://www.androidbegin.com/tutorial/flag/pakistan.png"
,"http://www.androidbegin.com/tutorial/flag/china.png","http://www.androidbegin.com/tutorial/flag/unitedstates.png"};
URL url;
HttpURLConnection urlConnection = null;
for(int i=0;i<imageUrl.length;i++){
url = new URL(imageUrl[i]);
//create the new connection
urlConnection = (HttpURLConnection) url.openConnection();
//set up some things on the connection
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
//and connect!
urlConnection.connect();
}
File storagePath = new File(Environment.getExternalStorageDirectory().getAbsolutePath() + File.separator + "Test");
storagePath.mkdirs();
String finalName = Long.toString(System.currentTimeMillis());
File myImage = new File(storagePath, finalName + ".png");
//this will be used to write the downloaded data into the file we created
FileOutputStream fileOutput = new FileOutputStream(myImage);
//this will be used in reading the data from the internet
InputStream inputStream = urlConnection.getInputStream();
//this is the total size of the file
int totalSize = urlConnection.getContentLength();
//variable to store total downloaded bytes
int downloadedSize = 0;
//create a buffer...
byte[] buffer = new byte[1024];
int bufferLength = 0; //used to store a temporary size of the buffer
//now, read through the input buffer and write the contents to the file
while ((bufferLength = inputStream.read(buffer)) > 0) {
//add the data in the buffer to the file in the file output stream (the file on the sd card
fileOutput.write(buffer, 0, bufferLength);
//add up the size so we know how much is downloaded
downloadedSize += bufferLength;
//this is where you would do something to report the prgress, like this maybe
// updateProgress(downloadedSize, totalSize);
}
//close the output stream when done
fileOutput.close();
//catch some possible errors...
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
// see http://androidsnippets.com/download-an-http-file-to-sdcard-with-progress-notification
return null;
}
** What I want :**
Download all the images one by one.
After downloading one Image it should get save in the device and update the progress status.
Please show me some source code rather then giving me just Idea how to do it. And little source code and complete work around on this would be appreciated.

the saving image code should be taken inside for loop. as this code is outside of for loop only your last image is getting saved as at the end of for loop last url is used.

Android: Image downloaded but not displayed in imageview

I have downloaded image from url to sd card. It is shown as normal thumbnail image in sd card but when i click it to view it a message is shown Could not load image also the image is not displayable in imageview. The image was downloaded with the help of Async Task. Now i want to check first if image is displayable or not. If not delete it and redownload it.
Code for downloading the images:
protected Void doInBackground(String... params) {
try{
String fileName = params[0].substring(params[0].lastIndexOf('/') + 1);
URL url = new URL(params[0]);
HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.setDoOutput(true);
urlConnection.connect();
File file = new File(SwipeActivity.filename,fileName);
FileOutputStream fileOutput = new FileOutputStream(file);
InputStream inputStream = urlConnection.getInputStream();
byte[] buffer = new byte[1024];
int bufferLength = 0;
while ( (bufferLength = inputStream.read(buffer)) > 0 )
{
fileOutput.write(buffer, 0, bufferLength);
}
fileOutput.close();
}
catch (Exception e) {
// TODO: handle exception
}
return null;
}
Any help is appreciated in advance.

You could try checking whether the image is displayable in build in Gallery app. Ive had this issue with, as it seemed, usual PNG image, the trick was it wasnt an RGB pic, but the CMYK color format. The output was similar to yours, android doesnt display CMYK images in a straight way

BitmapFactory returns null

I am working on an application where I am getting an image from the web server.
I need to save that image in a sqlite database. Maybe it will be saved in a byte[]; I have done this way, taking the datatype as blob, and then retrieving the image from db and showing at imageview.
I am stuck somewhere, however: I am getting null when I decodefrom bytearray
The code I have used is:
InputStream is = null;
try {
URL url = null;
url = new URL(http://....);
URLConnection ucon = null;
ucon = url.openConnection();
is = ucon.getInputStream();
} catch (MalformedURLException e1) {
e1.printStackTrace();
} catch (IOException e1) {
e1.printStackTrace();
}
BufferedInputStream bis = new BufferedInputStream(is);
ByteArrayBuffer barb = new ByteArrayBuffer(128);
int current = 0;
try {
while ((current = bis.read()) != -1) {
barb.append((byte) current);
} catch (IOException e) {
e.printStackTrace();
}
byte[] imageData = barb.toByteArray();
Then I have inserted imageData in to the db..
To retrieve the image:
byte[] logo = c.getBlob(c.getColumnIndex("Logo_Image"));
Bitmap bitmap = BitmapFactory.decodeByteArray(logo, 0, logo.length);
img.setImageBitmap(bitmap);
But I am getting the error:
Bitmap bitmap is getting null.

Sometimes, It happens, when your byte[] not decode properly after retrieving from database as blob type.
So, You can do like this way, Encode - Decode,
Encode the image before writing to the database:
ByteArrayOutputStream outputStream = new ByteArrayOutputStream();
mBitmap.compress(Bitmap.CompressFormat.JPEG, THUMB_QUALITY, outputStream);
mByteArray = outputStream.toByteArray(); // write this to database as blob
And then decode it like the from Cursor:
ByteArrayInputStream inputStream = new ByteArrayInputStream(cursor.getBlob(columnIndex));
Bitmap mBitmap = BitmapFactory.decodeStream(inputStream);
Also, If this not work in your case, then I suggest you to go on feasible way..
Make a directory on external / internal storage for your application
images.
Now store images on that directory.
And store the path of those image files in your database. So you
don't have a problem on encoding-decoding of images.

how to use an image stored in internal data storage in android

In my app when the splash screen gets started I am downloading an image from the URL. I want to use the same image in another activity of my app. Following is my code to download the image
public void DownloadImage(String fileName)
{
try
{
URL url = new URL(main.BannerImage); //you can write here any link
File file = new File(fileName);
Log.e("file ",""+file);
URLConnection ucon = url.openConnection();
InputStream is = ucon.getInputStream();
BufferedInputStream bis = new BufferedInputStream(is);
ByteArrayBuffer baf = new ByteArrayBuffer(50);
int current = 0;
while ((current = bis.read()) != -1)
{
baf.append((byte) current);
}
FileOutputStream fos = new FileOutputStream(file);
fos.write(baf.toByteArray());
fos.close();
}
catch (IOException e)
{
Log.e("Error: ","" + e);
}
How can I get the image as a background source in another activity please help me friends

You can save the image in SDCard and the path can be send to next activity using
intent.putExtras("filename","filepathname");
and get in the next activity using
getIntent().getExtras().getString("filename")
from this you can get filepath from previous activity and you can get the image from specific filepath.
You can convert the image into bitmap and and pass it to next activity using Parcelable like
Bundle extras = new Bundle();
extras.putParcelable("data",bitmap);
Intent intent=new Intent(currentActivity.this,nextImage.class);
intent.putExtras(extras);
startActivity(intent);
finish();
in nextactivity you can get bitmap as
Bitmap image=getIntent().getExtras().getParcelable("data");