What's the best/easiest way to rename a file in the application's internal storage? I find it a bit strange that there is a Context.deleteFile() method, but no "move" or "rename" function. Do I have to go all the way through saving the file's contents, deleting it, creating a new one and then copying the contents into that one? Or is there a way to copy a file over an existing file?
Update (Aug. 30, 2012):
As per the suggested solution below, which I cannot get to work:
I have a file called shoppinglists.csv
Then I create a new file called shoppinglists.tmp, and copy the contents from shoppinglists.csv AND some new entries into that. The shoppinglist.tmp file is then a new version of the shoppinglists.csv file
Then I delete the old shoppinglists.csv file
Then I need to rename the shoppinglists.tmp file to shoppinglists.csv
I tried this:
ctx.deleteFile("shoppinglists.csv"); <--- delete the old file
File oldfile = new File("shoppinglists.tmp");
File newfile = new File("shoppinglists.csv");
oldfile.renameTo(newfile);
However, this doesn't work. After deleteFile(), nothing more happens, and I'm left with the new shoppinglists.tmp file.
What am I missing?
NB: There are no errors or anything in LogCat.
Instead of using a raw File constructor, use the method getFileStreamPath provided by the Context. That is to say, do:
File oldfile = ctx.getFileStreamPath("shoppinglists.tmp");
File newfile = ctx.getFileStreamPath("shoppinglists.csv");
oldfile.renameTo(newfile);
renameTO() doesn't work in my environment (Eclipse Indigo, AVD with android version 2.3). The solution is to skip the temporary file method alltogeher, since it doesn't seem to be possible to solve in any reasonable time frame.
I think we cannot use File.renameTo() method in Internal Storage environment.
Renaming a file in this environment, can do:
- Copy content of the old file to new file.
- Delete old file.
File file = new File("your old file/folder name");
File file2 = new File("your new file/folder name");
boolean success = file.renameTo(file2);
Related
I want to create a sub directory which is non-private under the Environment.DIRECTORY_PICTURES directory. I used the code shown below but of no avail. The directory is created but it remains private. I don't know where I'm wrong.
File file = new File(Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES), "MyImages");
file.mkdirs();
File f = new File(file,"Image1");
First, you have not created a file, at least in the code that is shown above. You have created a Java File object, and you created a directory, but you did not create a file for Image1, and so your directory is empty. I know of no way to force your empty directory to be picked up by anything, though you should see it if you use adb shell or DDMS to examine your device.
When you do eventually write a file to this directory, be sure to call getFD().sync() on the FileOutputStream before you close() that stream. Then, use MediaScannerConnection and its static scanFile() method to have your newly-created file be indexed by the MediaStore. Until you do this, your newly-created file will not be visible via MTP or many third-party apps.
Could you please help me. renameTo() leaves empty old file. So I see 2 files in file system with new name and old name. The size of old file is 0. If I delete old file after renaming it says that file does not exist while staying in file system.
An absolute path of directory is:
/storage/sdcard0/DCIM/Camera
My code:
String dir = oldpath.substring(0, oldpath.lastIndexOf("/"));
File directory = new File(dir);
File from = new File(directory, oldfilename);
File to = new File(directory, newname);
renamed = from.renameTo(to);
Try this code:
File sdcard = new File("/storage/sdcard0/DCIM/Camera");
File from = new File(sdcard, "from.txt"); // Don't forget to set the file extension.
File to = new File(sdcard, "to.txt"); // In this case, we have a '.txt' file extension.
from.renameTo(to);
You can get the sdcard directory in String type programmatically by using this code:
String sdcard = Environment.getExternalStorageDirectory().getPath();
Don't forget to add this permission in manifest:
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
RenameTo leaves an empty copy of the original file if the file is opened by another process.
For example, I wanted to rename a file after the DownloadManager finished downloading it. The DownloadManager apparently notifies the BroadcastReceivers after the download, but before closing the file. This caused the renameTo in the onReceive to leave an empty copy. To solve this problem, I had to make the BroadcastReceiver to wait half a second before renaming the file.
You must remember about two things : The file and the file extension (file type). The following is wrong way sometimes, in case of deleting and renaming file :
File file = new File (dir+"/"+myfile)
The right way is :
File file = new File (dir, myfile+".db");
For the Full Aprroach, you could look at Answer Here.
I'm new to android development and I am working on a little project. What I am having some issue with is getting access to preloaded files.
In my app, I have an XML file that I preloaded (I just simply put it in my src folder in a package). How do I access them in my classes? I need to get a File object pointing to this file so that I can use it as I would I/O files. It seems like this should be trivial, but alas I am stuck.
Lets say the file is located under: com.app.preloadedFiles/file1.XML
I've tried something along the lines of this, but have had no success:
URL dir_url = ClassLoader.getSystemResource("preloadedFiles/file1.XML");
FIle file = new File(dir_url.toURI());
I solved this in my app by getting an InputStream to the file -- something like:
myContext.getAssets().open(fileName);
//read the data and store it in a variable
Then, if you truly need to do File related opterations with it, you can write it to a private (or public) directory and do your operations from you newly written file. Something like:
File storageDir = myContext.getDir(directoryName, Context.MODE_PRIVATE);
File myFile = new File(storageDir + File.separator + fileName);
//then, write the data to the file and manipulate it -- store the name for access via File later
I need to access myfile.txt file using FileReader in Android , please suggest me where to add the text file in Eclipse. I tried it adding it in Resource and Asset but I am getting File not found issue.
FileReader fr = new FileReader("myfile.txt");
Even
File ff = new File("myfile.txt");
File Supports only the below listed parameters
FileReader Supports only the below listed parameters
Note: I want solution for this issue , only with FileReader or File
The directory would be /res/raw/ this is where you put all your extra resources.
you can refer to it using getResources().openRawResource(resourceName)
and check here Android how to get access to raw resources that i put in res folder?
EDIT:
how can i edit the text files in assets folder in android
in short
the easiest way would be to copy the file to external directory then do your stuff there
link is here
Android: How to create a directory on the SD Card and copy files from /res/raw to it?
One thing to mention - prior to 2.3 the file size in the assets cannot exceed 1MB.
hope it helps abit
That's how I obtain my file from the SD card, perhaps this can be some use to you.
String state = Environment.getExternalStorageState();
if (Environment.MEDIA_MOUNTED.equals(state)) {
File options = new File(getAppDirectory(), "portal.xml");
}
The getAppDirectory method used in the bit of code looks like this :
private String getAppDirectory() {
return new String(Environment.getExternalStorageDirectory().toString()
+ "/foldername/foldername/");
}
After this bit of code I also make sure the file exists and what not before I attempt to read from it.
I want to create .nomedia file in the internal cache directory where I will store images and tried the following..
File dir = getCacheDir();
File output = new File(dir, ".nomedia");
boolean fileCreated = output.createNewFile();
When I try this fileCreated is false and the file doesn't get created.
If I used nomedia without a dot the file gets created but this is no use as the MediaScanner is looking if the .nomedia file exists.
I also tried this with a FileOutputStream and to write data in the file in case it was because I was only created an empty file but this doesn't work either.
Anyone have an idea why this could be failing?
Hmm, are you really sure that the file not already exists? Please note that you need to do an ls -a to see a file starting with a dot.
The documentation of File.createNewFile() says:
Returns true if the file has been
created, false if it already exists.
If the file is not created for other reasons (i.e. security), it should throw an exception.