IOException when trying to access SD card from android
everyone. I'm trying to save a picture with android to the public pictures directory on the sd card. However, I can't seem to get as far as opening a file for writing. Here is the code:
boolean mExternalStorageWriteable = false;
String state = Environment.getExternalStorageState();
if (Environment.MEDIA_MOUNTED.equals(state)) {
mExternalStorageWriteable = true;
}
if(mExternalStorageWriteable){
File root_dir = Environment.getExternalStorageDirectory();
root_dir.mkdirs();
File pictures_directory = new File(root_dir, "/Pictures/");
pictures_directory.mkdirs();
File outputfile = new File(pictures_directory, "test_file.jpg");
try {
outputfile.createNewFile();
FileOutputStream out = new FileOutputStream(outputfile);
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
My debugger always jumps to the catch block (caused by the createNewFile call) and the IOExceptions message is "Not a Directory". If I remove the createNewFile call, the FileOutPut开发者_开发知识库Stream constructor will throw a FileNotFound exception. Opening a fileoutput stream to the root of the file system or the pictures directory seems to work fine however.
To dispense with the obvious, my manifest includes the <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/> tag. I'm using API level 5 and my emulator has a virtual SD card mounted to it. Any suggestions are greatly appreciated.
SOLVED: There was a problem with the emulator filesystem. DDMS showed /Pictures/ being created as a file or a directory for some reason. Creating a new emulator solved the issue.
That's usually a bad manner to hard coder path separators. Try just Pictures
instead of /Pictures/
. The last one is an absolute path which point to a folder in root:
File pictures_directory = new File(root_dir, "Pictures");
UPD:
I have compiled and run your code snippet with no problems. So the problem is in your emulator file system. Try to remove that Pictures file first, or even create a new sdcard image for your emulator.
Your confusing the following two methods:
File(String Path)
and File(File dir, String name)
As such, pictures_directory should be a directory not a complete path + filename.
Try changing
File pictures_directory = new File(root_dir, "/Pictures/");
to
File pictures_directory = new File(root_dir + "/Pictures/");
Try this method. Make sure you have test_file.jpg in your res/drawable directory.
private void writeToSDCard() {
try {
File root = Environment.getExternalStorageDirectory();
if (root.canWrite()){
InputStream from = getBaseContext().getResources().openRawResource(R.drawable.test_file);
File dir = new java.io.File (root, "Pictures");
dir.mkdir();
File writeTo = new File(root, "Pictures/test_file.jpg");
FileOutputStream to = new FileOutputStream(writeTo);
byte[] buffer = new byte[4096];
int bytesRead;
while ((bytesRead = from.read(buffer)) != -1)
to.write(buffer, 0, bytesRead); // write
to.close();
from.close();
} else {
Log.d("MyActivity", "Unable to access SD card.");
}
} catch (Exception e) {
Log.d("MyActivity", "writeToSDCard: " + e.getMessage());
}
} "
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