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Read and write bitmap to android fails

I am trying to write and read a bitmap following the suggestions on other topics about this, the thing is i never get the bitmap when i try to read on the path where i saved the image:
So i have this to write the bitmap:
private String saveToInternalStorage(Bitmap bitmapImage){
ContextWrapper cw = new ContextWrapper(getApplicationContext());
// path to /data/data/yourapp/app_data/imageDir
File directory = cw.getDir("imageDir", Context.MODE_PRIVATE);
// Create imageDir
File mypath=new File(directory,"captured");
FileOutputStream fos = null;
try {
fos = new FileOutputStream(mypath);
// Use the compress method on the BitMap object to write image to the OutputStream
bitmapImage.compress(Bitmap.CompressFormat.JPEG, 100, fos);
} catch (Exception e) {
e.printStackTrace();
} finally {
try {
fos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return directory.getAbsolutePath();
}
}
i pass the returned path to another activity and then i pass it as parameter to get the bitmap like this:
private void loadImageFromStorage(String path)
{
try {
File f=new File(path, "captured.jpg");
Log.d("filehe",f.toString());
b = BitmapFactory.decodeStream(new FileInputStream(f));
}
catch (FileNotFoundException e)
{
e.printStackTrace();
}
}
i feel i am doing something wrong here, but can't figure out what, the b variavel has no value :/.
Any help?
Thanks

So i have this to write the bitmap:
The file that you save is named captured.
i pass the returned path to another activity and then i pass it as parameter to get the bitmap like this
Here, you are trying to load captured.jpg, which is not captured.
You could avoid this sort of problem by having the first method return the File that the second method then uses.
Also:
Use an image-loading library (e.g., Picasso, Glide) that has an in-memory cache, so you do not waste the user's time re-loading the same bitmap from disk
Get rid of ContextWrapper from the first method, as you do not need it

Displaying Base64-Encoded String of raw PDF data using ThinkFree PDF Viewer

The problem:
I'm getting a Base64-Encoded String of raw PDF data from a web service (this data is housed in my String array pdfData). I have to use this data display the PDF in a PDF viewer (I happen to be using the included 'ThinkFree PDF Viewer' since I'm working on an Android application, but lets generalize and say any PDF viewer will do). Note that I'm accessing the 0th element of this array just for testing purposes (to make sure I can at least pull up 1 PDF before writing the code to pull up all the PDFs).
The code is within a class. First the method createFile is called, then intentOpenPDF:
import org.apache.commons.codec.binary.Base64;
File file;
FileOutputStream outputStream;
private byte[] decodedContent;
private String[] pdfData;
private String[] pdfFileName;
public void createFile() {
decodedContent = Base64.decodeBase64(pdfData[0].getBytes());
try {
File path = new File(getFilesDir(), "PDFs");
if (!path.exists()) {
path.mkdirs();
}
file = new File(path, pdfFileName[0]);
outputStream = new FileOutputStream(file);
outputStream.write(decodedContent);
outputStream.close();
}
catch (FileNotFoundException ex) {
ex.printStackTrace();
}
catch (IOException ex) {
ex.printStackTrace();
}
finally {
// Make absolutely certain the outputStream is closed
try {
if (outputStream != null) {
outputStream.close();
}
}
catch (IOException ex) {
ex.printStackTrace();
}
}
}
public void intentOpenPDF() {
// Make sure the file exists before accessing it:
if (file.exists()) {
Uri targetUri = Uri.fromFile(file);
Intent intent = new Intent(Intent.ACTION_VIEW);
intent.setDataAndType(targetUri, "application/pdf");
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(intent);
}
}
The error:
Error opening file. It does not exist or cannot be read.
I have a break point set inside the conditional statement that checks if the file exists (within the intentOpenPDF method), and it IS passing this check.

The path produced by calling getFilesDir() leads a protected directory (file:///data/data/), where only files created with openFileOutput(String, int) are stored. I am not creating the file this way. The solution in my case is to use getExternalFilesDir(null).getAbsolutePath() instead, which will give you a path a directory internal to the application (/storage/emulated/0/Android/data/). No permissions are required to read or write to this path.

Considering your error message:
It does not exist or cannot be read.
as you verified it exists (first possible cause), it's certainly not readable (second possible cause).

New to Java. Problems reading from file using Context and openFileInput

I've been trying to do this on my own for the past couple hours and am kinda losing it a little.
All I want to do is open a file, read it and display it to the console; that's it.
I'm using eclipse to develop for android 2.3.3.
I have tried using a bunch of different ways with code that I have found here, and on other sites. Here is what I have now and how its all called:
In the OnCreate function:
setContentView(new TestMap(this));
The testMap class:
TestMap(Context context){
super(context);
// might need to be on the panel class
loadTileFile("worldonelayout.txt", context);
in the same class:
private void loadTileFile (String filename, Context context){
FileInputStream input = null;
InputStreamReader reader = null;
char[] inputBuffer = new char[256];
String data = null;
try {
input = context.openFileInput("worldonelayout.txt");
reader = new InputStreamReader(input);
reader.read(inputBuffer);
data = new String(inputBuffer);
System.out.println(data);
Toast.makeText(context, "Text read", Toast.LENGTH_SHORT).show();
} catch (Exception e) {
e.printStackTrace();
Toast.makeText(context, "Text not read", Toast.LENGTH_SHORT).show();
} finally {
try {
input.close();
reader.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
This code doesnt work. It always hits the exception.
"/data/data/com.name.somethingiremoved/files/worldonelayout.txt (No such file or directory)".
This happens at the first CATCH. BTW my file is in the root directory: Documents\Eclipse\workspace\project\worldonelayout.txt. I can also see the file in the browser on the left
From what I have seen here and on other sites, it is something to do with the Context class being derived from the Activity? I don't want to have this code in the same class as my activity. Is there a way round this?
If you need anything more from me, let me know.

The open file is looking for a file on the phone's file system, not on the computer's. Its telling you exactly where it expects to find it - on the phone under /data/data/com.name.somethingiremoved/files/worldonelayout.txt

Restoring data using AsyncTask

I have a saving method that runs during onPause():
String save = numberValue.getText().toString();
FileInputStream fos;
try {
fos = openFileOutput(FILENAME,Context.MODE_PRIVATE);
fos.write(save.getBytes());
fos.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
Toast.makeText(getBaseContext(), "Save has run", Toast.LENGTH_SHORT).show();
}
and I try to read this file by calling
new Loader().execute(FILENAME);
and my Loader class looks like this:
public class Loader extends AsyncTask<String, Integer, String> {
protected void onPostExecute(String result) {
textview.setText(result);
}
#Override
protected String doInBackground(String... params) {
FileInputStream fis;
String loaded = null;
try {
fis = openFileInput(FILENAME);
byte[] dataArray = new byte[fis.available()];
while (fis.read(dataArray) != -1) {
loaded = new String(dataArray);
}
fis.close();
textview.setText(loaded);
return loaded;
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return loaded;
}
}
And I have no idea as to why the textview does not get set as the bytes from FILENAME. The idea is that the textview is an increasing number, and this number gets saved when the activity is closed and gets restored to the textview when the activity starts up again.
It does start, I know that because after a few minutes, Watch Dog tells me that a background service from this app is consuming about 50% of CPU. I did check /data/data//files and the file that I write to is there with the correct value.

You probably need to call your Loader from onResume() for this to work.

Why not just save the state you need by using the onSavedInstanceState() method? Writing stuff out to the fileSystem on the onPause method is going to making switching out of your application really slow. From the Activity Documentation regarding the onPause method:
Called when the system is about to start resuming a previous activity. This is typically used to commit unsaved changes to persistent data, stop animations and other things that may be consuming CPU, etc. Implementations of this method must be very quick because the next activity will not be resumed until this method returns.
Also, from the android documentation:
In situations where the system needs more memory it may kill paused processes to reclaim resources. Because of this, you should be sure that all of your state is saved by the time you return from this function. In general onSaveInstanceState(Bundle) is used to save per-instance state in the activity and this method is used to store global persistent data (in content providers, files, etc.)
Here's where I got that from.

Serializing an ArrayList

I'm trying to write an Android game and I would like to be able to pause the game even if the user wants to return to the main menu or the activity gets killed off by the system. onSaveInstanceState doesn't seem to give me a whole lot of control as to when I can read the bundle back, plus from what I can tell, the bundle is only good for short periods of time. So I want to serialize a few ArrayLists that I have, then read them back. I don't get any compile errors nor does the program crash. But, the data either never gets written or never gets read. I'm not sure which one. My serializeData method is called in onDestroy and the deserializeData is called from onCreate. Here's my code for writing and reading the data:
public void serializeData(String filename, ArrayList<String>arrayList) {
FileOutputStream fos;
try {
fos = openFileOutput(filename, Context.MODE_PRIVATE);
ObjectOutputStream oos = new ObjectOutputStream(fos);
oos.writeObject(arrayList);
oos.close();
} catch (FileNotFoundException e) {
e.printStackTrace();
}catch(IOException e){
e.printStackTrace();
}
}
#SuppressWarnings("unchecked")
private void deserializeData(String filename, ArrayList<String>arrayList){
try{
FileInputStream fis = openFileInput(filename);
ObjectInputStream ois = new ObjectInputStream(fis);
arrayList = (ArrayList<String>)ois.readObject();
} catch (FileNotFoundException e) {
e.printStackTrace();
}catch(IOException e){
e.printStackTrace();
}catch(ClassNotFoundException e){
e.printStackTrace();
}
}
Any help would be greatly appreciated! Thanks in advance!

Let me tell you one thing: never use the onDestroy() method to save your data. Use onPause() or onStop() instead. You should never count on the onDestroy() method to save data or call some functions.
Use onDestroy to close connections and finish using resources and the like. If you want to read more about this you should take a look here.
Other than that your code seems fine. Just add one more thing: put a oos.flush() just above oos.close().
And don't forget to close the objectInputStream object.

I cannot see an obvious problem with that code.
I'd try adding some code after closing the ObjectOutputStream and before opening the ObjectInputStream to print out the absolute name and size of the file.

While serializing you can write to ByteArrayOutputStream and then decode the bytes into string using platform's default character set. Store this string into SharedPreferences. While deserializing, just get the bytes from string and create a ByteArrayInputStream using this and feed it to ObjectInputStream.Are you sure your activity is being killed? It might be the case that your activity is oscillating between onPasue/onResume.