I want to create a file in external storage sdCard and write to it.I have searched through internet and try but not getting the result,I have added permission in Android Manifest file as well,I am doing this on Emulator,I am trying the following code and getting a ERRR", "Could not create file".
btnWriteSDFile = (Button) findViewById(R.id.btnWriteSDFile);
btnWriteSDFile.setOnClickListener(new OnClickListener() {
//private Throwable e;
@Override
public void onClick(View v) {
// write on SD card file data from the text box
try {
File myFile = new File("/sdcard/mysdfile.txt");
myFile.createNewFile();
FileOutputStream fOut = new FileOutputStream(myFile);
OutputStreamWriter myOutWriter = new OutputStreamWriter(fOut);
myOutWriter.append(txtData.getText());
myOutWriter.close();
fOut.close();
} catch (Exception e) {
Log.e("ERRR", "Could not create file",e);
}
}// onClick
}); // btnWriteSDFile
This question is related to
android
android-layout
android-emulator
ContextWrapper contextWrapper = new ContextWrapper(getApplicationContext()); //getappcontext for just this activity context get
File file = contextWrapper.getDir(file_path, Context.MODE_PRIVATE);
if (!isExternalStorageAvailable() || isExternalStorageReadOnly())
{
saveToExternalStorage.setEnabled(false);
}
else
{
External_File = new File(getExternalFilesDir(file_path), file_name);//if ready then create a file for external
}
}
try
{
FileInputStream fis = new FileInputStream(External_File);
DataInputStream in = new DataInputStream(fis);
BufferedReader br =new BufferedReader(new InputStreamReader(in));
String strLine;
while ((strLine = br.readLine()) != null)
{
myData = myData + strLine;
}
in.close();
}
catch (IOException e)
{
e.printStackTrace();
}
InputText.setText("Save data of External file:::: "+myData);
private static boolean isExternalStorageReadOnly()
{
String extStorageState = Environment.getExternalStorageState();
if (Environment.MEDIA_MOUNTED_READ_ONLY.equals(extStorageState))
{
return true;
}
return false;
}
private static boolean isExternalStorageAvailable()
{
String extStorageState = Environment.getExternalStorageState();
if (Environment.MEDIA_MOUNTED.equals(extStorageState))
{
return true;
}
return false;
}
You can find these method usefull in reading and writing data in android.
public void saveData(View view) {
String text = "This is the text in the file, this is the part of the issue of the name and also called the name od the college ";
FileOutputStream fos = null;
try {
fos = openFileOutput("FILE_NAME", MODE_PRIVATE);
fos.write(text.getBytes());
Toast.makeText(this, "Data is saved "+ getFilesDir(), Toast.LENGTH_SHORT).show();
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}finally {
if (fos!= null){
try {
fos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
public void logData(View view) {
FileInputStream fis = null;
try {
fis = openFileInput("FILE_NAME");
InputStreamReader isr = new InputStreamReader(fis);
BufferedReader br = new BufferedReader(isr);
StringBuilder sb= new StringBuilder();
String text;
while((text = br.readLine()) != null){
sb.append(text).append("\n");
Log.e("TAG", text
);
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}finally {
if(fis != null){
try {
fis.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
To write into external storage in Lollipop+ devices we need:
Add the following permission into Manifest:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
Request an approval from the user:
public static final int REQUEST_WRITE_STORAGE = 112;
private requestPermission(Activity context) {
boolean hasPermission = (ContextCompat.checkSelfPermission(context, Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED);
if (!hasPermission) {
ActivityCompat.requestPermissions(context,
new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},
REQUEST_WRITE_STORAGE);
} else {
// You are allowed to write external storage:
String path = Environment.getExternalStorageDirectory().getAbsolutePath() + "/new_folder";
File storageDir = new File(path);
if (!storageDir.exists() && !storageDir.mkdirs()) {
// This should never happen - log handled exception!
}
}
Handle the user response inside Activity:
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
switch (requestCode)
{
case Preferences.REQUEST_WRITE_STORAGE: {
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
Toast.makeText(this, "The app was allowed to write to your storage!", Toast.LENGTH_LONG).show();
// Reload the activity with permission granted or use the features what required the permission
} else {
Toast.makeText(this, "The app was not allowed to write to your storage. Hence, it cannot function properly. Please consider granting it this permission", Toast.LENGTH_LONG).show();
}
}
}
After writing to external storage, some file managers don't see the file right away. This can be confusing if a user thinks they copied something to the SD card, but then can't find it there. So after you copy the file, run the following code to notify file managers of its presence.
MediaScannerConnection.scanFile(
context,
new String[]{myFile.getAbsolutePath()},
null,
null);
See the documentation and this answer for more.
Even though above answers are correct, I wanna add a notice to distinguish types of storage:
Here is the link to source code for cases I mentioned above: https://github.com/mttdat/utils/blob/master/utils/src/main/java/mttdat/utils/FileUtils.java
You should read the documentation on storing stuff externally on Android. There's a multitude of problems that could exist with your current code, and I think going over the documentation might help you iron them out.
The code below creates a Documents directory and then a sub-directory for the application and saved the files to it.
public class loadDataTooDisk extends AsyncTask<String, Integer, String> {
String sdCardFileTxt;
@Override
protected String doInBackground(String... params)
{
//check to see if external storage is avalibel
checkState();
if(canW == canR == true)
{
//get the path to sdcard
File pathToExternalStorage = Environment.getExternalStorageDirectory();
//to this path add a new directory path and create new App dir (InstroList) in /documents Dir
File appDirectory = new File(pathToExternalStorage.getAbsolutePath() + "/documents/InstroList");
// have the object build the directory structure, if needed.
appDirectory.mkdirs();
//test to see if it is a Text file
if ( myNewFileName.endsWith(".txt") )
{
//Create a File for the output file data
File saveFilePath = new File (appDirectory, myNewFileName);
//Adds the textbox data to the file
try{
String newline = "\r\n";
FileOutputStream fos = new FileOutputStream (saveFilePath);
OutputStreamWriter OutDataWriter = new OutputStreamWriter(fos);
OutDataWriter.write(equipNo.getText() + newline);
// OutDataWriter.append(equipNo.getText() + newline);
OutDataWriter.append(equip_Type.getText() + newline);
OutDataWriter.append(equip_Make.getText()+ newline);
OutDataWriter.append(equipModel_No.getText()+ newline);
OutDataWriter.append(equip_Password.getText()+ newline);
OutDataWriter.append(equipWeb_Site.getText()+ newline);
//OutDataWriter.append(equipNotes.getText());
OutDataWriter.close();
fos.flush();
fos.close();
}catch(Exception e){
e.printStackTrace();
}
}
}
return null;
}
}
This one builds the file name
private String BuildNewFileName()
{ // creates a new filr name
Time today = new Time(Time.getCurrentTimezone());
today.setToNow();
StringBuilder sb = new StringBuilder();
sb.append(today.year + ""); // Year)
sb.append("_");
sb.append(today.monthDay + ""); // Day of the month (1-31)
sb.append("_");
sb.append(today.month + ""); // Month (0-11))
sb.append("_");
sb.append(today.format("%k:%M:%S")); // Current time
sb.append(".txt"); //Completed file name
myNewFileName = sb.toString();
//Replace (:) with (_)
myNewFileName = myNewFileName.replaceAll(":", "_");
return myNewFileName;
}
Hope this helps! It took me a long time to get it working.
Source: Stackoverflow.com