I implemented a share button in my app. When I want to share, I can select a saved json data from the device and select via which way I want to share it (mail etc.). The problem is, that the data is NOT in the attachements. The problem is likely because I use the internal app storage. Therefore I want to save tje json data into the external storage, what would be better in my case anyway. But I am not really sure how to do that. I am not sure if I should use the Media type of content of the Documents and other files type of content which is provided by android. There is also the Appspecific files type but this looks like it is not applicaple for me, because I need to share the json data wit ha share functin. At the moment my code looks like this:
Save Function, which get's a file name I can choose myself
private void saveState(String name) {
File file = new File(getFilesDir(), name + ".json");
try{
OutputStream out = new FileOutputStream(file);
MyJsonWriter writer = new MyJsonWriter();
writer.writeJsonStream(out, ... //data structure);
out.close();
}catch (Exception e){
Log.e("saveState ERROR", "----------------------------------------------------");
}
}
LoadButtonClick Functin which shows me all files
public void loadStateClick(View view) {
final LinearLayout layout = new LinearLayout(MainActivity.this);
layout.setOrientation(LinearLayout.VERTICAL);
String[] files = MainActivity.this.fileList();
... //more code which is not important here
Load Function
private void loadState(String name) {
File file = new File(getFilesDir(), name);
InputStream in = null;
... //setting my data structure, not important here
try{
in = new FileInputStream(file);
MyJsonReader reader = new MyJsonReader(MainActivity.this);
SaveData savedData = reader.readJsonStream(in);
... // handling data structure, not important here
in.close();
}catch (Exception e){
Log.e("LOAD ERROR", e.toString());
}
}
Related
When I try to read some files in my Android app they appear to not exist, here is my code:
public class ReadFiles1 {
//Static Scanner and File Objects
static Scanner s;
// Static method that returns an ArrayList
static ArrayList<String> words (String filename){
//Instantiate File with file name within parameters
File n = new File(filename);
//Instantiate Scanner s with f variable within parameters
//surround with try and catch to see whether the file was read or not
try {
s = new Scanner(n);
} catch (FileNotFoundException e) {
e.printStackTrace();
System.out.println("Problem here");
}
//Instantiate a new ArrayList of String type
ArrayList<String> theWord = new ArrayList <String>();
//while it has next ..
while(s.hasNext()){
//Initialise str with word read
String str=s.next();
//add to ArrayList
theWord.add(str);
}
//return ArrayList
return theWord;
}
I don't know what the problem is, I put the txt files in the same package as the .java files.
This is the error I get when runnning this:
check this link for PICTURE(https://ibb.co/cn3QCv)
W/System.err: java.io.FileNotFoundException: build/numbers.txt: open failed: ENOENT (No such file or directory)
Don't put your text files in java folder instead put it in
app/src/main/res/raw/ folder and read it in program using below code.
static ArrayList<String> words (InputStream in) {
try {
s = new Scanner(in);
} catch (FileNotFoundException e) {
e.printStackTrace();
System.out.println("Problem here");
}
and call this method from any activity or service using below code
InputStream in = getResources().openRawResource(R.raw.numbers);
ArrayList<String> words = ReadFiles1.words(in);
or if you're calling this method from any other class then should have context reference
InputStream in = context.getResources().openRawResource(R.raw.numbers);
ArrayList<String> words = ReadFiles1.words(in);
Hope this will work.
I am used to opening my files in my apps using the next code:
public void openFile(#NonNull String uri) {
checkNotNull(uri);
File file = new File(uri);
String dataType = null;
if (ContentTypeUtils.isPdf(uri)) dataType = "application/pdf";
else if (ContentTypeUtils.isImage(uri)) dataType = "image/*";
if (file.exists() && dataType != null) {
Intent target = new Intent(Intent.ACTION_VIEW);
target.setDataAndType(Uri.fromFile(file), dataType);
target.setFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
Intent intent = Intent.createChooser(target, "Open file");
try {
startActivity(intent);
} catch (ActivityNotFoundException e) {
e.printStackTrace();
Log.e(TAG, "There is a problem when opening the file :(");
}
} else {
Toast.makeText(getContext(), "Invalido", Toast.LENGTH_LONG).show();
}
}
I had always used static files so this was enough, but now I am using the Google Drive SDK for Android. I possess the driveId of the file I want to open but the problem is I cannot find a clean way to open the file contents I obtain by doing this:
Drive.DriveApi.fetchDriveId(mGoogleApiClient, documentFile.getDriveId())
.setResultCallback(driveIdResult -> {
PendingResult<DriveApi.DriveContentsResult> open =
driveIdResult.getDriveId().asDriveFile().open(
mGoogleApiClient,
DriveFile.MODE_READ_ONLY,
null);
open.setResultCallback(result -> {
DriveContents contents = result.getDriveContents();
InputStream inputStream = contents.getInputStream();
// I know I can get the input stream, and use it to write a new file.
});
});
So the only thing that comes to my mind is creating a static route to create a file every time I have to open it, and erasing it every time I have to open a new file.
What I have understood up until now is that the Google Drive API for Android already saves an instance of the file so what I have in mind sounds unnecessary, I would like to know if there is a better way to achieve this. Is there a way I can open the file and do something similar to what I do with the Intent.ACTION_VIEW in a cleaner way?
Thanks in advance.
Well since it seems this will not be answered I will post what I did. All I did was create a temp file where I put my contents to be read. I still don't know if it was the best choice so this question will still be opened for a better answer.
open.setResultCallback(result -> {
DriveContents contents = result.getDriveContents();
InputStream inputStream = contents.getInputStream();
writeTempFile(inputStream);
});
And here the implementation of the `writeTempFile`:
private synchronized File writeTempFile(#NonNull InputStream inputStream) {
checkNotNull(inputStream);
File filePath = new File(mActivity.getFilesDir(), "TempFiles");
if (!filePath.exists()) filePath.mkdirs();
File file = new File(filePath, TEMP_FILE);
try {
OutputStream outputStream = new FileOutputStream(file);
IOUtils.copyLarge(inputStream, outputStream);
IOUtils.closeQuietly(inputStream);
IOUtils.closeQuietly(outputStream);
} catch (IOException e) {
e.printStackTrace();
}
return file;
}
I have an android app that is writing a values to a file that the app also creates. I am able to write to the file and then again read from the file. However, as soon as that activity is finished, it seems that the file is now gone, or loses it's values.
I know you can't browse the files through explorer unless you root your phone and/or run the adb server as a specific user.
Here is my code for writing to the file:
public void savePrices(View view) {
FileOutputStream outputStream;
File getFilesDir = this.getFilesDir();
File filePathOne = new File(getFilesDir, filename);
try {
outputStream = openFileOutput(filename, Context.MODE_PRIVATE);
for (int i = 0; i < priceArray.length; i++) {
outputStream.write(String.format("%.2f\n", priceArray[i]).getBytes());
}
Toast.makeText(this, "Prices saved successfully!", Toast.LENGTH_SHORT).show();
outputStream.close();
} catch (Exception e) {
e.printStackTrace();
}
Here is my code that reads the file:
public void loadPrices(View view) {
int i = 0;
final InputStream file;
BufferedReader reader;
try{
file = getAssets().open(filename);
reader = new BufferedReader(new InputStreamReader(file));
String line = reader.readLine();
while(line != null){
line = reader.readLine();
priceArray[i] = Double.parseDouble(line);
i++;
}
} catch(IOException ioe){
ioe.printStackTrace();
hamburgerPriceText.setText(String.format("%.2f", priceArray[0]));
hotDogPriceText.setText(String.format("%.2f", priceArray[1]));
chipsPriceText.setText(String.format("%.2f", priceArray[2]));
beerPriceText.setText(String.format("%.2f", priceArray[3]));
popPriceText.setText(String.format("%.2f", priceArray[4]));
Toast.makeText(this, "Prices loaded successfully!", Toast.LENGTH_SHORT).show();
}catch (NumberFormatException e) {
Log.e("Load File", "Could not parse file data: " + e.toString());
}
}
After I call the save method which sets the values in the array and saves the values to the file, I run a clear method that removes all the values on the activity fields and in the array. So when I run the read method and it populates the fields on the activity, I know the values are coming from reading the file. This is the only way that I know that I'm saving and reading from the file successfully.
My question is how do I make it permanent? If I close the activity that saves the values and then immediately run the read method, all the values are 0.
Is there something that I am missing? How can I write to a file so if the activity is closed, or the app is completely closed, I can still retain the values?
Here is my code that reads the file:
There is nothing in that code that reads a file. It is reading some stuff out of the your app's assets. Also, for some reason, it is only updating the UI if you have an exception.
So when I run the read method and it populates the fields on the activity, I know the values are coming from reading the file.
No, they are coming from your app's assets, and you are only populating the fields if you have an IOException.
My question is how do I make it permanent?
Step #1: Actually read from the file. Since you are using openFileOutput() to write to the file, use openFileInput() to read from the file.
Step #2: Update the UI when you successfully read in the data, not in the catch block for the IOException.
I´m trying to save my values to .csv file with this code.
try {
CSVWriter writer = new CSVWriter(new FileWriter(getFilesDir()+"ECGValues.csv"),',');
// feed in your array (or convert your data to an array)
String[] entries = Values_to_save.toArray(new String[Values_to_save.size()]);
writer.writeNext(entries);
writer.close();
Values_to_save.clear();
Toast.makeText(this,"ECG values saved", Toast.LENGTH_SHORT).show();
} catch (IOException e) {
Toast.makeText(this,"Error while saving values", Toast.LENGTH_SHORT).show();
Log.e("error", "" + e.getMessage());
Log.e("error",""+ e.getStackTrace());
}
My input data is from
Lead_I_save =String.valueOf(IValue);
Lead_II_save = String.valueOf(IIValue);
Lead_III_save = String.valueOf(IIIValue);
Lead_aVL_save = String.valueOf(aVLValue);
Lead_aVF_save = String.valueOf(aVFValue);
Lead_aVR_save = String.valueOf(aVRValue);
String newLine = String.format("%1$s;%2$s;%3$s;%4$s;%5$s;%6$s;",
Lead_I_save, Lead_II_save, Lead_III_save,
Lead_aVL_save, Lead_aVF_save, Lead_aVR_save);
Values_to_save.add(newLine);
A Toast appears with ECG values saved, but I cannot find the .csv anywhere.
I will welcome any suggestions. Thanks
You used a relative path (only a file name) and then your file lands in the apps private internal memory which is unreachable for other apps. Use a full path to external memory instead.
So I want to save whatever users write in their EditText to be saved for the next time. This exact same code works for java project but with Android project, it doesnt work.
The code is below.
The PrintWriter out = new PrintWriter("hi"); always gives the FileNotFoundException e.
In java project, this code The PrintWriter out = new PrintWriter("hi"); makes a new file with the name "hi" but android project does not produce a new file instead returns the error. It does not save the String from the EditText to be opened when the app opens up again later.
Does anyone have a solution to this problem?
public void onCreate(blablabla)
{blablabla
try {
FileReader reader = new FileReader ("hi");
Scanner in = new Scanner(reader);
String line = in.nextLine();
mEditText.setText(line);
in.close();
} catch (FileNotFoundException e) {
mEditText.setText("");
Toast.makeText(mContext, "null!!", Toast.LENGTH_SHORT).show();
}
#Override
protected void onDestroy()
{
super.onDestroy();
// The activity is about to be destroyed.
try {
PrintWriter out = new PrintWriter("hi");
out.write(mEditText.toString());
out.close();
} catch (FileNotFoundException e) {
Toast.makeText(mContext, "Can't save", Toast.LENGTH_SHORT).show();
}
}
May be Android permission problem. See http://developer.android.com/guide/topics/manifest/manifest-intro.html#perms
Or better to use SharedPreferences?