GUYS
I'm new to android and this is my first post in StackOverflow.English as my second language,I'm not that good at it.I just looked for some answers here before,Now I think it's time for me to get involved in it.
There have been a problem occured when I try to copy the system log which located in /dev/log/* to my SD card.After some search on the answers here,I came across Copy file (image) from CacheDir to SD Card.So I had my code below:
private final String srcLocation = "/dev/log/radio";
private final String desLocation = "/mnt/sdcard/radio";
FileInputStream src;
FileOutputStream dst;
FileChannel mFCsrc;
FileChannel mFCdst;
public boolean copyFile(String sourceLocation, String destLocation) throws IOException {
try {
File sd = Environment.getExternalStorageDirectory();
if(sd.canWrite()){
File source=new File(sourceLocation);
File dest=new File(destLocation);
if(!dest.exists()){
dest.createNewFile();
}
if(source.exists()){
src = new FileInputStream(source);
dst = new FileOutputStream(dest);
mFCsrc = src.getChannel();
mFCdst = dst.getChannel();
mFCsrc.transferTo(0, mFCsrc.size(), mFCdst);
}
}
return true;
} catch (Exception ex) {
ex.printStackTrace();
return false;
} finally {
if (mFCsrc != null) {
mFCsrc.close();
}
if (mFCdst != null) {
mFCdst.close();
}
}
}
I do have the file in my SD card which I can see it from my DDMS window,but it's size is 0.So,anyone gets a clue? Thanks in advance.(I try to give you a picture of my DDMS window,but since my reputation is not enough,I cann't use a picture.I'm sorry about that!!)
You should debug. Step trough your code with the debugger and check what is happening.
Random thing that might be happening, but we have no way of knowing for sure: If "source" doesn't exist, you will create dest, but because source.exists() will return false,you don't do anything after that. You'll end up with the current behaviour, a newly created file without contents.
Related
I am used to opening my files in my apps using the next code:
public void openFile(#NonNull String uri) {
checkNotNull(uri);
File file = new File(uri);
String dataType = null;
if (ContentTypeUtils.isPdf(uri)) dataType = "application/pdf";
else if (ContentTypeUtils.isImage(uri)) dataType = "image/*";
if (file.exists() && dataType != null) {
Intent target = new Intent(Intent.ACTION_VIEW);
target.setDataAndType(Uri.fromFile(file), dataType);
target.setFlags(Intent.FLAG_ACTIVITY_NO_HISTORY);
Intent intent = Intent.createChooser(target, "Open file");
try {
startActivity(intent);
} catch (ActivityNotFoundException e) {
e.printStackTrace();
Log.e(TAG, "There is a problem when opening the file :(");
}
} else {
Toast.makeText(getContext(), "Invalido", Toast.LENGTH_LONG).show();
}
}
I had always used static files so this was enough, but now I am using the Google Drive SDK for Android. I possess the driveId of the file I want to open but the problem is I cannot find a clean way to open the file contents I obtain by doing this:
Drive.DriveApi.fetchDriveId(mGoogleApiClient, documentFile.getDriveId())
.setResultCallback(driveIdResult -> {
PendingResult<DriveApi.DriveContentsResult> open =
driveIdResult.getDriveId().asDriveFile().open(
mGoogleApiClient,
DriveFile.MODE_READ_ONLY,
null);
open.setResultCallback(result -> {
DriveContents contents = result.getDriveContents();
InputStream inputStream = contents.getInputStream();
// I know I can get the input stream, and use it to write a new file.
});
});
So the only thing that comes to my mind is creating a static route to create a file every time I have to open it, and erasing it every time I have to open a new file.
What I have understood up until now is that the Google Drive API for Android already saves an instance of the file so what I have in mind sounds unnecessary, I would like to know if there is a better way to achieve this. Is there a way I can open the file and do something similar to what I do with the Intent.ACTION_VIEW in a cleaner way?
Thanks in advance.
Well since it seems this will not be answered I will post what I did. All I did was create a temp file where I put my contents to be read. I still don't know if it was the best choice so this question will still be opened for a better answer.
open.setResultCallback(result -> {
DriveContents contents = result.getDriveContents();
InputStream inputStream = contents.getInputStream();
writeTempFile(inputStream);
});
And here the implementation of the `writeTempFile`:
private synchronized File writeTempFile(#NonNull InputStream inputStream) {
checkNotNull(inputStream);
File filePath = new File(mActivity.getFilesDir(), "TempFiles");
if (!filePath.exists()) filePath.mkdirs();
File file = new File(filePath, TEMP_FILE);
try {
OutputStream outputStream = new FileOutputStream(file);
IOUtils.copyLarge(inputStream, outputStream);
IOUtils.closeQuietly(inputStream);
IOUtils.closeQuietly(outputStream);
} catch (IOException e) {
e.printStackTrace();
}
return file;
}
i am breaking my brain trying to attach an arm pre-compiled binary to my private android app.
if you don't mind, i tell you about my app. it just needs to modify iptables rules because of my gprs communication with my robot. it is a remote control for android, and i get better results if i deny all traffic instead my robot's one.
so i compiled an iptables with my cyanogenmod's version 11 iptables, but with -save -restore support, since i want to restore the rules after finishing the control of my robot..
the thing is that i've been searching in google for a lot of while, and i just found droidwall which seems to only create a 'raw' directory into the 'res' top dir, and once installed, i can see on adb shell the folder 'app_bin' inside /data/data's path.
but when i do install my app, with those dirs createds i can not see even the binary in some strange path... really, is this a very rare case? I don't find any documentation on the network...
thanks a lot,
hope you find it helpful.
abel.
EDIT (possible sollution)
I've downloaded the code from android_firewall project, where it seems to be copying from the apk resource, to the bin directory:
./src/com/jtschohl/androidfirewall/Api.java: final String app_iptables = dir + "/iptables_armv5";
./src/com/jtschohl/androidfirewall/Api.java: // Check iptables_armv5
./src/com/jtschohl/androidfirewall/Api.java: File file = new File(ctx.getDir("bin", 0), "iptables_armv5");
./src/com/jtschohl/androidfirewall/Api.java: copyRawFile(ctx, R.raw.iptables_armv5, file, "755");
I am going to try. Keep on news...
Yes, this is the sollution. The folder name "app_%{TYPE}" is the one returned by the calling of the function getDir(%{TYPE}, MODE_PRIVATE);
So the following code, does the desired functionality:
private static void copyRawFile(Context ctx, int resid, File file, String mode) throws IOException, InterruptedException {
final String abspath = file.getAbsolutePath();
// Write the iptables binary
final FileOutputStream out = new FileOutputStream(file);
final InputStream is = ctx.getResources().openRawResource(resid);
byte buf[] = new byte[1024];
int len;
while ((len = is.read(buf)) > 0) {
out.write(buf, 0, len);
}
out.close();
is.close();
// Change the permissions
Runtime.getRuntime().exec("chmod " + mode + " " + abspath).waitFor();
}
private boolean assertBinaries(Context ctx, boolean showErrors) {
try {
File file = new File(ctx.getDir("bin", MODE_PRIVATE), "xtables_multi");
if (!file.exists()) {
copyRawFile(ctx, R.raw.xtables_multi, file, "755");
}
file = new File(ctx.getDir("bin", MODE_PRIVATE), "iptables_new.sh");
if (!file.exists()) {
copyRawFile(ctx, R.raw.iptables_new, file, "755");
}
} catch(Exception e) {
if (showErrors) {
alert(ctx, R.string.error_assertbinaries + " " + e);
}
return false;
}
return true;
}
public static void alert(Context ctx, CharSequence msg) {
if (ctx != null) {
Toast.makeText(ctx, msg, Toast.LENGTH_SHORT).show();
}
}
Hope that helps,
cheers; Abel.
I have a database of recipes, each of which has an image.
The database can be updated from a JSON feed. I then need to retrieve any new images for a newly added recipe. I'm having issues getting an image from a URL, saving it and then updating a recipe with that image.
There are a lot of different answers on Stack Overflow and other sites. Often I can get to what I would expect to be a working point. Where images appear to be getting saved, and any debug print outs I add in show what I expect, but I cannot update my ImageView. By that I mean it remains blank.
I'm not sure if my issue is simply a poor attempt to update the ImageView, or a problem when saving the images. This code is a bit sloppy and inefficient at the moment. I've tried 10-15 variations on this from suggested other posts and have had no luck. Any help would be greatly appreciated.
Manifest
/* I have these two set (Not sure both are necessary) */
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
Main frontend class
/* Create databaseHelper */
DatabaseHelper db = new DatabaseHelper(getApplicationContext());
/* ImageView to update image of */
ImageView foodpic = (ImageView)findViewById(R.id.foodpic);
/* Check if image is already available in drawable folder */
int resID = this.getResources().getIdentifier(filename, "drawable", "mypackage.name");
if (resID == 0) {
/* If not, call function to retrieve from external storage */
newPic = db.getOutputMediaFile(origFilename);
if(newPic.exists()) {
myBitmap = BitmapFactory.decodeFile(newPic.getAbsolutePath());
foodpic.setImageBitmap(myBitmap);
foodpic.invalidate(); /* Tried with and without this */
}
}
DatabaseHelper function to retrieve image saved from URL
public File getOutputMediaFile(String filename){
/* Dir I'm (attempting) to save and retrieve images from */
File mediaStorageDir = new File(Environment.getExternalStorageDirectory() + "/Android/data/mypackage.name/Files");
/* Create the storage directory if it does not exist */
if (! mediaStorageDir.exists()){
if (! mediaStorageDir.mkdirs()){
return null;
}
}
/* Get file extension */
String[] fileNameSplit = filename.split("\\.");
String extension = fileNameSplit[(fileNameSplit.length-1)];
/* Get filename, remove special chars & make lowercase */
int extensionIndex = filename.lastIndexOf(".");
filename = filename.substring(0, extensionIndex);
filename = filename.toLowerCase(Locale.getDefault());
filename = filename.replaceAll("[^a-z0-9]", "");
/* Re-make filename to save image as */
String mImageName="r"+filename+"."+extension;
/* Get file
mediaFile = new File(mediaStorageDir.getPath() + File.separator + mImageName);
return mediaFile;
}
DatabaseHelper function to save image from URL
- Called per recipe/image added to the database, if image not found in drawable folder.
public static void saveImage(String imageUrl, String destinationFile, String extension) throws IOException {
URL url = new URL (imageUrl);
InputStream input = url.openStream();
try {
File storagePath = Environment.getExternalStorageDirectory();
OutputStream output = new FileOutputStream (new File(storagePath,destinationFile));
try {
byte[] buffer = new byte[2048];
int bytesRead = 0;
while ((bytesRead = input.read(buffer, 0, buffer.length)) >= 0) {
output.write(buffer, 0, bytesRead);
}
} finally {
output.close();
}
} finally {
input.close();
}
*Formatting.
Store URL as string in DB and display it with Image Loader is more easy, but doesn't work off line ,if ur apps need internet to work, the image loader could be better.
android-loading-image-from-url-http
I ended up using this library.
It's not an ideal solution as I'd have preferred to look through this library, understand it fully and explain it for others who may need a similar answer. But for now, people attempting to do something similar should be able to use this too.
https://code.google.com/p/imagemanager/
I want to ensure a byte array is being converted to a jpg correctly.
I've simplified the problem as follows:
public String saveToFile(String filename, String contents) {
String storageState = Environment.getExternalStorageState();
if(!storageState.equals(Environment.MEDIA_MOUNTED)) {
throw new IllegalStateException("Media must be mounted");
}
File directory = Environment.getExternalStorageDirectory();
File file = new File(directory, filename);
FileWriter fileWriter;
try {
fileWriter = new FileWriter(file, false);
fileWriter.write(contents);
fileWriter.close();
return file.getAbsolutePath();
} catch (Exception e) {
e.printStackTrace();
return null;
}
}
#Test
public void testDummyTest() throws Exception{
String out = saveToFile("preview-test.jpg", "preview-test.jpg");
}
This test passes and the path is something like file:///var/folders/z_/_syx1dpx7v9_pmktgdbx7f_m0000gn/T/android-external-cache8656399524188278404robolectric/ddf1c2ec-c0a8-44ce-90e4-7de2a384c57f/preview-test.jpg
However, I can't find this file my machine (yes, I've searched for it). I suspect this is a temp cache and its being cleared/deleted before I can view it.
Please can you tell me how to locate the "preview-test.jpg" file so I may open it in an image viewer, thus proving the image looks like it should. Thanks.
Note: the problem is not the jpg encoding, its simply getting direct access to the file.
I found a partial solution.
Rather than using the shadow environment to provide a path, I can instead use an absolute path for the machine. Eg root "/" would work.
So the code would look something like...
public String saveToFile(String filename, String contents) throws IOException {
File file = new File("/", filename);
FileWriter fileWriter;
fileWriter = new FileWriter(file, false);
fileWriter.write(contents);
fileWriter.close();
return file.getAbsolutePath();
}
#Test
public void testDummyTest() throws Exception {
String out = saveToFile("preview-test.jpg", "preview-test.jpg");
}
This then leaves a file on the root directory of the machine. :) Hope this helps somebody else out there.
ey up. ive built a simple music app that reads wav files from the sdcard and plays them.
how do i access the default media directory?
this is how i get the sdcard
public void LoadSounds() throws IOException
{
String extState = Environment.getExternalStorageState();
if(!extState.equals(Environment.MEDIA_MOUNTED)) {
//handle error here
}
else {
File sd = new File(Environment.getExternalStorageDirectory ()); //this needs to be a folder the user can access, like media
as usual the docs dont give an actual example of usage but it says this - If you're using API Level 8 or greater, use getExternalFilesDir() to open a File that represents the external storage directory where you should save your files. This method takes a type parameter that specifies the type of subdirectory you want, such as DIRECTORY_MUSIC...
how do i use it?
thank you
edit:
this makes it crash if i try to fill a spinner array with file path Strings.
File path = getExternalFilesDir(Environment.DIRECTORY_MUSIC);
File sd = new File(path, "/myFolder");
File[] sdDirList = sd.listFiles(new WavFilter());
if (sdDirList != null)
{
//sort the spinner
amountofiles = sdDirList.length;
array_spinner=new String[amountofiles];
......
final Spinner s = (Spinner) findViewById(R.id.spinner1); //crashes here
ArrayAdapter<?> adapter = new ArrayAdapter<Object>(this,
android.R.layout.select_dialog_item, array_spinner);
EDIT2:
ok so ive done this test that is supposed to write a txt file to the music directory.
i run the app, no txt file is written anywhere on the device i can find.
// Path to write files to
String path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MUSIC).getAbsolutePath();
String fname = "mytest.txt";
// Current state of the external media
String extState = Environment.getExternalStorageState();
// External media can be written onto
if (extState.equals(Environment.MEDIA_MOUNTED))
{
try {
// Make sure the path exists
boolean exists = (new File(path)).exists();
if (!exists){ new File(path).mkdirs(); }
// Open output stream
FileOutputStream fOut = new FileOutputStream(path + fname);
fOut.write("Test".getBytes());
// Close output stream
fOut.flush();
fOut.close();
} catch (IOException ioe) {
ioe.printStackTrace();
}
}
another edit: i will get this working!!
so if i use this line it creates a folder on the sdcard called 'Musictest'. dont understand??
String path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MUSIC + "test").getAbsolutePath();
////////////////////////////////////////////////////////////////////
Final Edit:
right so this will look for a folder called test in the devices music directory.
if it doesnt exist, it will be created.
(some fixing to be done here, error if empty) it then lists the files in the directory and adds them to an array.
public void LoadSounds() throws IOException
{
String extState = Environment.getExternalStorageState();
// Path to write files to
String path = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_MUSIC + "/test").getAbsolutePath();
if(!extState.equals(Environment.MEDIA_MOUNTED)) {
//handle error here
}
else {
//do your file work here
// Make sure the path exists
boolean exists = (new File(path)).exists();
//if not create it
if (!exists){ new File(path).mkdirs(); }
File sd = new File(path);
//This will return an array with all the Files (directories and files)
//in the external storage folder
File[] sdDirList = sd.listFiles();
if (sdDirList != null)
{
//add the files to the spinner array
array_spinnerLoad=new String[sdDirList.length];
files = new String[sdDirList.length];
for(int i=0;i<sdDirList.length;i++){
array_spinnerLoad[i] = sdDirList[i].getName();
files[i] = sdDirList[i].getAbsolutePath();
}
}
}
}
as mentioned in the docs, getExternalFilesDir() return File. And File object can represent either file or directory.
Therefore:
File musicDirectory = new File( getExternalFilesDir(Environment.DIRECTORY_MUSIC));
Will give you the object to play with.