i was trying to read a .txt file (from assets) in items of a list, so i was doing this:
list.add(await rootBundle.loadString('assets/jolo.txt'));
It takes the whole document and put it in 'data', but at showing the list is empty.
So i tried something else:
new File('assets/jolo.txt')
.openRead()
.transform(utf8.decoder)
.transform(new LineSplitter())
.forEach((l) => list.add(Item(name: l)));
but that throws me an error:
FileSystemException: Cannot open file, path = 'assets/jolo.txt' (OS Error: No such file or directory, errno = 2)
What can i do? I'm using plain text for putting every line into an item for show the whole list
To load an asset you must use the bundle. loadString takes care of reading the asset and dealing with the encoding so you get a String. Use LineSplitter.convert on the string:
String jolo = await rootBundle.loadString('assets/jolo.txt');
List<Item> list =
LineSplitter().convert(jolo).map((s) => Item(name: s)).toList();
You may not be running in the directory that you think.
Try looking at Directory.current() to see where you are running.
Related
This code works:
string file = Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData), "File.text");
File.ReadAllText(file);
Pretty straight-forward, but when I display the variable "file" using a Pizel 5 simulator I get a weird path: /data/user/0/com.companyname.aikidohours/files/.local/share/File.text. I can write new data to the file and read from it. but I now want to read from an existing file and I can't figure out where to put the file. Can someone tell where to put a text file full of basic information that I need to read from in Xamarin for adnroid?
Thanks
Todd
If you want to deploy that file with your application, you can add it to the 'Assets' folder inside your_project_name.Android project.
WARNING!!! File put in this folder are READONLY!
In case this is ok for you,this is the code to access the file:
using Xamarin.Essentials;
using (var reader = new StreamReader(await FileSystem.OpenAppPackageFileAsync("file_path")))
{
string content = reader.ReadToEnd();
}
I'm storing user data in ApplicationData folder. Its path is obtained with :
userDataPath = System.IO.Path.Combine(System.Environment.GetFolderPath(System.Environment.SpecialFolder.ApplicationData), "userData");
This variable is equal to /data/user/0/APPNAME/files/.config/userData.
Each time I rebuild the project, if I delete the userData file with File.Delete(userDataPath), I can successfully create the file, write and read to it several times. I can indeed check the created file in /data/data/APPNAME/files/.config/userData.
I check in /data/data/.../.config/userData and not in /data/user/.../.config/userData because apparently the latter is a symlink to the former, so it should be equivalent ? Moreother I don't have access to /data/user/.../.config/userData.
The problem is that if I rebuild the app without deleting the file, I got an unhandled exception at the following Deserialization (which worked fine before) :
if (File.Exists(userDataPath))
{
Stream reader = new FileStream(userDataPath, FileMode.Open);
Console.WriteLine(userDataPath);
userData = (UserData)serializer.Deserialize(reader); // ERROR HERE
reader.Close();
}
It is very strange because the file located at /data/data/APPNAME/files/.config/userData does not exist but since File.Exists(userDataPath) is true, the file located at /data/user/0/APPNAME/files/.config/userData does exist.
So how can this be explained and is this the correct way to store data in ApplicationData folder ?
After switching to another SpecialFolder (LocalApplicationData), I can't reproduce the unhandeld exception anymore (even when switching back to ApplicationData).
I'll keep this post updated if it ever happens again.
Im currently trying to save some values in a text file in Processing Android (APDE). I want to later use this in another context, so it's important to use a complete file path. From Processing documentation for loadStrings():
... Alternatively, the file maybe be loaded from anywhere on the local
computer using an absolute path (something that starts with / on Unix
and Linux, or a drive letter on Windows)
So it must be possible.
I already searched for a answer, but never found something for Processing.
So my code is:
String[] saveData;
int score;
void setup(){
saveData=loadStrings("/storage/emulated/0/dataP/hi.txt");
score=parseInt(saveData[0]);
fullScreen();
frameRate(60);
noStroke();
noSmooth();
textAlign(CENTER);
textSize(height/20);
}
void draw(){
background(0);
fill(255) ;
text(score, width/2,height/2);
}
void mousePressed(){
score--;
saveData[0]=str(score);
println(saveData[0]);
saveStrings("/storage/emulated/0/hi.txt" ,saveData);
}
and I get the following error:
java.lang.IllegalArgumentException: File
/storage/emulated/0/dataP/hi.txt contains a path separator
I believe the confusion stems from the fact that loadStrings() method works differently for Java mode and Android mode. In Java mode, it is definitely possible to give loadStrings() an absolute Path with included separators, but in Android mode, loadStrings() will only work if you only specify a name without any separator (assumes by default to be looking into the data folder). Therefore, having any separator inside loadStrings() will throw the error.
One simple workaround you can try is to first create a separate path variable:
String path = "/storage/emulated/0/dataP/hi.txt";
And then give that as parameter to the loadStrings() method:
saveData = loadStrings(path);
If you were to use an SD card for storage, for example, you could do something like:
String SDCARD = Environment.getExternalStorageDirectory().getAbsolutePath();
File file = new File(SDCARD + File.separator + "mytext.txt");
String[] s = loadStrings(file.getPath());
As explained in the link in the comment I posted, loadStrings() and saveStrings() does not take absolute path as argument. What it means is that it can only access files with path "name.txt" and not "folder/name.txt". You have to do it using a FileInputStream and FileOutputStream if you must use absolute path. There are many examples of both these files on StackOverflow.
Dropbox now have an apsolutely new API, which is absolutely differ from the old one (it's interesting why), but there's no ANY actual examples in the internet, so I've found only some code in their examples. Here is it:
// Download the file.
try (OutputStream outputStream = new FileOutputStream (file)) {
mDbxClient.files ()
.download (metadata.getPathLower (), metadata.getRev ())
.download (outputStream);
}
I need to download file from remote folder to the local one, so I need to use this path for example:
.download ("Backups/backup.ab", "/storage/sdcard/Folder/backup.ab")
I've tried it, but get a error
IllegalArgumentException: String 'rev' does not match pattern'
Do you know, what it can be, and metadata.getPathLower () and metadata.getRev () methods are using for? I've learned, that metadata var gets from the first argv from execute (), but what this functions do?
Thanks a lot!
Not sure if if works for android. I have posted the following method just in case someone is looking for a C# .net solution.
private async Task Download(DropboxClient dbx, string folder, string file, string localFilePath)
{
using (var response = await dbx.Files.DownloadAsync(folder + "/" + file))
{
using (var fileStream = File.Create(localFilePath))
{
(await response.GetContentAsStreamAsync()).CopyTo(fileStream);
}
}
}
Parameter example:
file = "YourFileName.pdf";
folder = "/YourDropboxFolderName";
localFilePath = #"C:\Users\YourUserName\YourFileName.pdf";
The Dropbox API v2 Java SDK's download method takes these two parameters:
String path
String rev
Per the download method documentation there, the first is the remote path of the file in Dropbox you want to download, and the second is the identifier for the revision of the file you want. The second parameter is not the local path where you want to save the file, as it appears you're supplying in your code. Instead, you save the file content using the .download (outputStream); portion of the sample code you posted, e.g., as also shown in this sample code.
Also, as stated in the documentation, the second parameter is deprecated and should no longer be used. You can just use the version of the download method that only takes the one parameter. The code for using it is otherwise the same as the sample.
For reference, in the sample, the metadata object is an instance of FileMetadata. You can find more information on the getPathLower and getRev methods in the documentation as well.
Good afternoon everyone,
I'm having a problem here with an CSV file that I wanna use to fill a dynamic table in Android.
I placed the file in the "data" folder of my emulator, and I did the following declaration to create my file variable:
file = new File("/data/Motors.csv");
I used a CSVReader class posted on another thread from this page (Link to the class) and also declared the following line to do the parse:
readerCSV = new CSVReader(new FileReader(file),';','"',0);
In the last line, the programmer to be able to create the variable has to send as parameters a Reader (Or a FileReader, it doesn't make a difference), the separator char, the quote char and the number of how many lines the CSV reader has to skip.
The problem comes that no matter in which directory (Not even in the root directory, which Java tells me that it's "/" through the file.getAbsolutePath(); method) it always gets to the point when the program throws the FileNotFoundException and I'm getting a bit frustrated because I have 2 days already with this problem.
If someone could please help me to get a bit of orientation of what I should do to get the file from the right directory... It would be a lot of help and I can go further with the code I have to finish.
Many thanks in advance!!!!
EDIT
I found a solution to open my file:
I have used 2 file variables: one gets the rout of the External Storage Directory (see first answer in the following link) and the other is declared as a new file, like the following lines in the code:
route = Environment.getExternalStorageDirectory();
file = new File(route,"Motors.csv");
Later I used again the CSV reader class that I found, where the first parameter is from the FileReader type (Sorry #Rajesh, but I couldn't use your alternative because you passed a FileDescription parameter from the AssetManager to the CSV reader class and then I had to change the whole class and that didn't help my problem at all).
Now I don't get the exception at all!!
There are various Storage Options in Android. Files can be stored in internal and external storages. If the CSV file is a static resource, you could think of bundling the file in the "assets" folder of your project.
If you are using the "assets" route, the following code segment can get you a CSVReader.
AssetManager am = getAssets();
AssetFileDescriptor afd = am.openFd ("Motors.csv");
FileDescriptor fd = afd.getFileDescriptor();
readerCSV = new CSVReader(fd, ';','"',0);
The above code snippet doesn't perform error/exception handling, please remember to take care of that. You need to copy the Motors.csv file to the "assets" folder within the project.