Install the app for Android
2) Run the app in a simulator and verify that you are able to create files
3) Create a simple Android app in Eclipse and use 'Uri.parse' to create an uri to
a 'file' Uri. This uri should be persisted and the path retrieved. Once you are
successful in getting this uri, copy it to the clipboard.
4) Run the sample on an Android device
5) On the Android device, use 'intent:ACTION_SEND' to open the "File Manager"
activity. Select a file from there and copy its URI to the clipboard.
6) Launch an instance of the sample on an Android device and use a suitable file
picker to choose the URI you copied in step 5.
7) The app should successfully retrieve the path to the file.
8) Copy the code to your Android project and run the sample.
See the file "res/values/strings.xml" for possible values that can be supplied
to the 'file_chooser_callback' parameter.
Please note that this sample will probably only work on devices with Android 2.3 or higher.
is a file uri provided by the caller
(e.g. path/to/file).
is a string to use as a title for the chooser dialog
(e.g. Select a file).
is a list of extensions to include in the file chooser dialog
(e.g. all, jpg, pdf).
is a persistent (store between calls) path to a file to use as the selected
file (e.g. /sdcard/myfile.jpg)
This sample does not display the selected file because it may be larger than
allocated memory on low end devices.
Android 2.2 introduces an undocumented API to launch the Android file manager
without displaying a file chooser dialog. However, this API appears to have
recently changed and is not available on the Android emulator.
For more details, see the Android API docs for the undocumented
"android.content.Intent.ACTION_GET_CONTENT" intent action.
Note that the file manager uses a complex dialog view model that is not
supported in most cases. This sample does not attempt to handle these dialogs.
When used on Android 2.3, this app will launch the file manager only if the
file chooser can't be displayed in a popup, which may happen if the user has
restricted access to the external storage directory (e.g. /mnt/sdcard).
Android 2.3 is known to behave differently in that case, depending on
whether the user has selected a secure or non-secure storage.
The following sample app shows how to retrieve this file Uri with FileProvider.
Note that this app is very similar to the above sample with a few differences.
The Uri for the File Provider is obtained using 'getUriForFile'.
* MainActivity.java
private Uri mFilePath;
private void handleIntent(Intent intent) {
if (isExternalStorageAvailable()) {
// This will prompt the user to choose a file and show the file chooser dialog.
// We expect that once the user has chosen a file, the file chooser will return the file Uri.
// Once the file Uri has been retrieved, FileProvider.getUriForFile() should be used to retrieve the
// file contents. Since the file has already been chosen, the UI should not be invoked.
Uri uri = intent.getData();
mFilePath = FileProvider.getUriForFile(this, "com.example.android.fileprovider", new File(uri));
}
}
private boolean isExternalStorageAvailable() {
String state = Environment.getExternalStorageState();
return state.equals(Environment.MEDIA_MOUNTED);
}
MainActivity.java
private void openFileChooser() {
Intent intent = new Intent(Intent.ACTION_GET_CONTENT);
intent.addCategory(Intent.CATEGORY_OPENABLE);
intent.setType("*/*");
startActivityForResult(Intent.createChooser(intent, "Select a file"), REQUEST_PICKFILE);
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (requestCode == REQUEST_PICKFILE && resultCode == RESULT_OK) {
Uri uri = data.getData();
// This will invoke the 'show' method in MainActivity.handleIntent() which
// displays the file chooser dialog and retrieves the selected file's Uri.
show(uri);
}
}
File provider app source
The source code for the file chooser app is included below.
Note that only one activity is needed for this sample since it uses a file
chooser dialog. In a real app, one would launch an activity to start the file
picker, then check that resultCode == RESULT_OK and use the returned Uri from
the intent as the input for a separate activity.
res/values/strings.xml
Pick a file...file:///mnt/sdcard/myfile.pdfSelect a fileSelect a filePlease choose a file
res/layout/activity_main.xml
res/layout/dialog_pick_file.xml
