I've created Test.txt on sdcard and write string "test example" on it.
after that, I replace string "test" by "etc" in Test.txt.
this is my code :
String origin_str, old_str , new_str;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_t2);
origin_str = "test example";
old_str = "test";
new_str = "etc";
Button bt_create2 = (Button)findViewById(R.id.bt_createfileT2);
bt_create2.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
try {
File newFolder = new File(Environment.getExternalStorageDirectory(), "TestFolder");
if (!newFolder.exists()) {
newFolder.mkdir();
}
File file = new File(newFolder, "Test" + ".txt");
if (!file.exists()) {
file.createNewFile();
FileOutputStream fOut = new FileOutputStream(file);
OutputStreamWriter myOutWriter =new OutputStreamWriter(fOut);
myOutWriter.append(origin_str);
myOutWriter.close();
fOut.close();
}
} catch (Exception e) {
System.out.println("e: " + e);
}
}
});
Button bt_replacefileT2 = (Button)findViewById(R.id.bt_replacefileT2);
bt_replacefileT2.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
try {
File file = new File(Environment.getExternalStorageDirectory() + "/TestFolder/Test.txt");
FileInputStream in = new FileInputStream(file);
int len = 0;
byte[] data1 = new byte[1024];
while ( -1 != (len = in.read(data1)) ){
if(new String(data1, 0, len).contains(old_str)){
String s = "";
s = s.replace(old_str, new_str);
}
}
}
catch (Exception e){
e.printStackTrace();
}
}
});
with this code, it was create Test.txt on sdcard and write "test example" on it.
but when replace string "test" by "etc", it not working.
how to fix it?
I will give my code, always worked for me :)
Hope thi can help you :DD
public void saveString(String text){
if(this.isExternalStorageAvailable()){
if(!this.isExternalStorageReadOnly()){
try {
FileOutputStream fos = new FileOutputStream(
new File(this.getExternalFilesDir("text"), "text.dat"));
ObjectOutputStream oos = new ObjectOutputStream(fos);
oos.writeBytes(text);
oos.close();
fos.close();
} catch (FileNotFoundException e) {
//Toast.makeText(main, "Eror opening file", Toast.LENGTH_SHORT).show();
} catch (IOException e) {
//Toast.makeText(main, "Eror saving String", Toast.LENGTH_SHORT).show();
}
}
}
}
private static boolean isExternalStorageAvailable(){
String estadoSD = Environment.getExternalStorageState();
if(Environment.MEDIA_MOUNTED.equals(estadoSD))
return true;
return false;
}
private static boolean isExternalStorageReadOnly(){
String estadoSD = Environment.getExternalStorageState();
if(Environment.MEDIA_MOUNTED_READ_ONLY.equals(estadoSD))
return true;
return false;
}
public String getString(){
FileInputStream fis = null;
ObjectInputStream ois = null;
if(this.isExternalStorageAvailable()) {
try {
fis = new FileInputStream(
new File(this.getExternalFilesDir("text"), "text.dat"));
ois = new ObjectInputStream(fis);
String text = (String)ois.readObject();
return familia;
} catch (FileNotFoundException e) {
//Toast.makeText(main, "The file text doesnt exist", Toast.LENGTH_SHORT).show();
} catch (StreamCorruptedException e) {
//Toast.makeText(main, "Eror opening file", Toast.LENGTH_SHORT).show();
} catch(EOFException e){
try {
if(ois != null)
ois.close();
if(fis != null)
fis.close();
} catch (IOException e1) {
e1.printStackTrace();
}
} catch (IOException e) {
//Toast.makeText(main, "eror reading file", Toast.LENGTH_SHORT).show();
} catch (ClassNotFoundException e) {
//Toast.makeText(main, "String class doesnt exist", Toast.LENGTH_SHORT).show();
}
}
return null;
}
try this
File file = new File(Environment.getExternalStorageDirectory() + "/TestFolder/Test.txt");
try {
BufferedReader br = new BufferedReader(new FileReader(file));
String line;
while ((line = br.readLine()) != null) {
line = line.replace(old,new);
}
br.close();
FileOutputStream fOut = new FileOutputStream(file);
OutputStreamWriter myOutWriter =new OutputStreamWriter(fOut);
myOutWriter.write(line);
myOutWriter.close();
fOut.close();
}
catch (IOException e) {
//You'll need to add proper error handling here
}
Related
I have created a file and written into the file using editText. Now I want to write into a file named "note.txt". But the content to be written should be stored in a variable. Can any one help me with the code??
private void writeFile() {
File extStore = Environment.getExternalStorageDirectory();
// ==> /storage/emulated/0/note.txt
String path = extStore.getAbsolutePath() + "/" + fileName;
Log.i("ExternalStorageDemo", "Save to: " + path);
String data = editText.getText().toString();
try {
File myFile = new File(path);
myFile.createNewFile();
FileOutputStream fOut = new FileOutputStream(myFile);
OutputStreamWriter myOutWriter = new OutputStreamWriter(fOut);
myOutWriter.append(data);
myOutWriter.close();
fOut.close();
Toast.makeText(getApplicationContext(), fileName + " saved", Toast.LENGTH_LONG).show();
} catch (Exception e) {
e.printStackTrace();
}
}
Do you mean this?:
private void save(String inputText) {
FileOutputStream out = null;
BufferedWriter writer = null;
try{
out = openFileOutput("note.txt",Context.MODE_PRIVATE);
writer = new BufferedWriter(new OutputStreamWriter(out));
writer.write(inputText);
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}finally {
try{
if (writer!=null);
writer.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
In my MainActivity class in onResume method I start writeFile method. The class which contains the method:
public class CacheFile {
private static final String TAG = "CacheFile";
private static final String mFileName="cachefile.txt";
private static File file;
//Write data into the file
public static void writeFile(Context context, String data) {
FileOutputStream outputStream=null;
String oldData=readFile(context)+"&"+data;
try {
file = new File(context.getCacheDir(), mFileName);
outputStream = new FileOutputStream(file);
if(data!=null) {
outputStream.write(oldData.getBytes());
}
} catch (IOException e) {
e.printStackTrace();
}finally {
if(outputStream!=null){
try{
outputStream.close();
}catch (Exception e){
e.printStackTrace();
}
}
}
}
//Read from file
public static String readFile(Context context) {
BufferedReader inputStream = null;
FileInputStream fis = null;
StringBuffer buffer = new StringBuffer();
String line;
try {
file = new File(context.getCacheDir(), mFileName);
fis=new FileInputStream(file);
inputStream = new BufferedReader(new InputStreamReader(fis));
while ((line = inputStream.readLine()) != null) {
buffer.append(line);
}
} catch (IOException e) {
e.printStackTrace();
}finally {
if(inputStream!=null){
try{
inputStream.close();
}catch (Exception e){
e.printStackTrace();
}
}
if(fis!=null){
try{
fis.close();
}catch (Exception e){
e.printStackTrace();
}
}
}
return buffer.toString();
}
public static void deleteFile(Context context){
if(file!=null){
file.delete();
}
}
}
The first I readFile and add the information for writing but when I try to read file I get FileNotFoundException in line:
fis=new FileInputStream(file) (readfile method).
Why?
This means the file really doesn't exist. Do this:
file.createNewFile();
fis = new FileInputStream(file);
// Other code
You can read about createNewFile() here. It only creates the file if it doesn't already exist.
i have a imageview , i am trying to save bitmap from imageview by this method
bmp.compress(Bitmap.CompressFormat.PNG, 100, fos);
fos.close();
the rgb of saved image is not like that it looks in running app,so i am wondering if there is any way to save image view directly to a sd card rather getting the bitmap and then save it to sd card.
please help me i have tried everything.
You can read and write object using below code :
public static void witeObjectToFile(Context context, Object object, String filename)
{
ObjectOutputStream objectOut = null;
try
{
FileOutputStream fileOut = context.openFileOutput(filename, Activity.MODE_PRIVATE);
objectOut = new ObjectOutputStream(fileOut);
objectOut.writeObject(object);
fileOut.getFD().sync();
} catch (IOException e)
{
e.printStackTrace();
} finally
{
if (objectOut != null)
{
try
{
objectOut.close();
} catch (IOException e)
{
// do nowt
}
}
}
}
public static Object readObjectFromFile(Context context, String filename)
{
ObjectInputStream objectIn = null;
Object object = null;
try
{
FileInputStream fileIn = context.getApplicationContext().openFileInput(filename);
objectIn = new ObjectInputStream(fileIn);
object = objectIn.readObject();
} catch (FileNotFoundException e)
{
// Do nothing
} catch (IOException e)
{
e.printStackTrace();
} catch (ClassNotFoundException e)
{
e.printStackTrace();
} finally
{
if (objectIn != null)
{
try
{
objectIn.close();
} catch (IOException e)
{
// do nowt
}
}
}
return object;
}
For example ArrayList can be saved as :
ImageView abcImage = (ImageView) readObjectFromFile(context, AppConstants.FILE_PATH_TO_DATA);
and write as :
witeObjectToFile(context, abcImage, AppConstants.FILE_PATH_TO_DATA);
Try to use this
public void onClick(View v) {
if (v.getId() == R.id.btnSaveImage) {
imageView.setDrawingCacheEnabled(true);
Bitmap bm = imageView.getDrawingCache();
storeImage(bm);
}
}
private boolean storeImage(Bitmap imageData) {
// get path to external storage (SD card)
String iconsStoragePath = Environment.getExternalStorageDirectory() + "/yourappname/";
File sdIconStorageDir = new File(iconsStoragePath);
// create storage directories, if they don't exist
sdIconStorageDir.mkdirs();
try {
File file = new File(sdIconStorageDir.toString() + File.separator + "fileName");
FileOutputStream fileOutputStream = new FileOutputStream(file);
BufferedOutputStream bos = new BufferedOutputStream(fileOutputStream);
imageData.compress(CompressFormat.PNG, 100, bos);
bos.flush();
bos.close();
MediaScannerConnection.scanFile(this, new String[] { file.getPath() },
new String[] { "image/jpeg" }, null);
Toast.makeText(this, "Snapshot Saved to " + file, Toast.LENGTH_SHORT).show();
} catch (FileNotFoundException e) {
return false;
} catch (IOException e) {
return false;
}
return true;
}
I want to retain some strings even when i clear my app data so i am using text files saved in sd card.
I am using sd card files to store myStrings and read them at run time. but each and every time readfile return null.
following is my code:
protected void writeToFile(String data, String fileName) {
String root_sd = Environment.getExternalStorageDirectory().toString();
File dir = new File(root_sd+"/"+"AntiVirusPref");
if(dir.mkdir())
{
File f=new File( dir.getAbsolutePath()+"/"+fileName);
if (f.exists()) {
f.delete();
}
if (!f.exists()) {
try {
f.createNewFile();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
else {
File f=new File( dir.getAbsolutePath()+"/"+fileName);
if (f.exists()) {
f.delete();
}
if (!f.exists()) {
try {
f.createNewFile();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
try {
OutputStreamWriter outputStreamWriter = new OutputStreamWriter(openFileOutput(fileName, Context.MODE_PRIVATE));
outputStreamWriter.write(data);
outputStreamWriter.close();
}
catch (IOException e) {
Log.e("Exception", "File write failed: " + e.toString());
}
}
protected String readFromFile(String fileName, String defaultValue) {
String ret = "";
String root_sd = Environment.getExternalStorageDirectory().toString();
File dir = new File(root_sd+"/"+"AntiVirusPref");
File file = new File(dir.getAbsolutePath() + "/"+fileName);
try {
//InputStream inputStream = openFileInput("/sdcard/"+fileName);
FileInputStream inputStream = new FileInputStream(file);
if ( inputStream != null ) {
InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
String receiveString = "";
StringBuilder stringBuilder = new StringBuilder();
/*if((receiveString = bufferedReader.read) != null){
stringBuilder.append(receiveString);
}*/
String line="";
int c;
while ((c = bufferedReader.read()) != -1) {
line+=(char)c;
//counter++;
}
stringBuilder.append(line);
inputStream.close();
ret = stringBuilder.toString();
}
}
catch (FileNotFoundException e) {
Log.e("login activity", "File not found: " + e.toString());
} catch (IOException e) {
Log.e("login activity", "Can not read file: " + e.toString());
}
if (ret.equals("")) {
ret=defaultValue;
}
return ret;
}
try to add the "file:///" suffix before the Uri
I have an application consist on reading AND saving an xml file and to write it if internet connection is available,else it will read the file already saved on the terminal.
WriteFeed function:
// Method to write the feed to the File
private void WriteFeed(RSSFeed data) {
FileOutputStream fOut = null;
ObjectOutputStream osw = null;
try {
fOut = openFileOutput(fileName, MODE_PRIVATE);
osw = new ObjectOutputStream(fOut);
osw.writeObject(data);
osw.flush();
}
catch (Exception e) {
e.printStackTrace();
}
finally {
try {
fOut.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
WriteFeed function:
// Method to read the feed from the File
private RSSFeed ReadFeed(String fName) {
FileInputStream fIn = null;
ObjectInputStream isr = null;
RSSFeed _feed = null;
File feedFile = getBaseContext().getFileStreamPath(fileName);
if (!feedFile.exists())
return null;
try {
fIn = openFileInput(fName);
isr = new ObjectInputStream(fIn);
_feed = (RSSFeed) isr.readObject();
}
catch (Exception e) {
e.printStackTrace();
}
finally {
try {
fIn.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return _feed;
}
I have enough diskSpace ,sometimes i get "MemoryCach will use up to 16 Mb" ,always i get "Not enough disk space,will not index" and "FeatureCode > cannot open file"
whats wrong in my app?