I've had to upload a separate expansion file with my app (developed in Qt) in Google Play console. It's a simple rcc file. I have the name of file after the upload (it shows on the google console page). But I can't seem to find any info o how to get the shared-storage path (as mentioned) on the Android docs page (http://developer.android.com/google/play/expansion-files.html#StorageLocation).
I did come across this question (How to add android expansion files using Qt) where the user seems to have solved the issue but doesn't give any details on how to get the shared-storage path.
I've solved it:
I converted a qrc containing the large files to a binary using the qt rcc tool, then I used the following code to call the proper methods from the Qt Android Activity and retrieve the correct path to the expansion files:
QAndroidJniObject mediaDir = QAndroidJniObject::callStaticObjectMethod("android/os/Environment", "getExternalStorageDirectory", "()Ljava/io/File;");
QAndroidJniObject mediaPath = mediaDir.callObjectMethod( "getAbsolutePath", "()Ljava/lang/String;" );
QAndroidJniObject activity = QAndroidJniObject::callStaticObjectMethod("org/qtproject/qt5/android/QtNative", "activity", "()Landroid/app/Activity;");
QAndroidJniObject package = activity.callObjectMethod("getPackageName", "()Ljava/lang/String;");
QString dataAbsPath = mediaPath.toString()+"/Android/obb/"+package.toString()+"/yourExpansionFileName.obb";
QAndroidJniEnvironment env; // Don't know what this is for ?
if (env->ExceptionCheck()) { env->ExceptionClear(); } // Or this...?
bool loadResource = QResource::registerResource(dataAbsPath);
Don't forget to add #include <QAndroidJniEnvironment> in your app (and QT += androidextras in pro file), and last add this permission to the manifest (as the expansion file is located inside the external storage):
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>
I didn't check if the file was there or not before loading (every device I tested worked straight), but the android docs say you might need to download it manually. There is also some catch to uploading expansion files, you can only add them with the second apk submission (in Google play).
This code may be help you.
QStringList systemEnvironment = QProcess::systemEnvironment();
looking for
EXTERNAL_STORAGE=/storage/emulated/legacy
EXTERNAL_ADD_STORAGE=/storage/external_SD
SECONDARY_STORAGE=/storage/external_SD
...
This code worked for me:
QString s = QStandardPaths::writableLocation(QStandardPaths::movieLoaction);
QDir MyDir;
s = s + "/MyFolder"
MyDir.mkdir(s);
In your Android device you must check the storage permissions for your application. If not add this permission then run the application.
Related
Am using this code to try to read a particular directory an android devices.. this is the code in a released application. it works fine on all devices except SamSung devices..
fetchFromOriginalDirectory() async{
var result = await PhotoManager.requestPermission();//getting permission to check files
if (result) {
Directory dir = Directory('/storage/emulated/0/');
List<FileSystemEntity> _files;
_files = dir.listSync(recursive: true, followLinks: false).reversed.toList();//getting all files(stickers) in this directory
for(FileSystemEntity entity in _files) {//for each file gotten do this
String path = entity.path;
I first thought the problem was this line "/storage/emulated/0/" but after using multiple plugins to check for the right path. i found out the paths are the same. But for some reason the app cant read the files on samsung files. even after all permissions have been granted
Hey guys i fixed it by doing this
<application
android:requestLegacyExternalStorage="true" //adding this line
>
In the android manifest file.
I'm developing an app on android using Qt 5.15.0. My app creates a database and some other files using QStandardPaths::AppDataLocation. everything works fine from the code side: debug output makes me think the files are there and that the app is using them. The problem is that when I search from the PC inside the smartphone folders I cannot find the files created. So this makes me think I am not writing to the folder I'm expecting to.
This is my code:
appDataPath = QStandardPaths::writableLocation(QStandardPaths::AppDataLocation);
QDir directory;
if (!directory.exists(appDataPath + QStringLiteral("/DATABASE")))
directory.mkpath(appDataPath + QStringLiteral("/DATABASE"));
if (!directory.exists(appDataPath + QStringLiteral("/DATA")))
directory.mkpath(appDataPath + QStringLiteral("/DATA"));
qDebug() << "Percorso: " << appDataPath << " dir exists:" << directory.exists(appDataPath + QStringLiteral("/DATABASE"));
QFile f( appDataPath + "/DATABASE/Prova.txt" );
if( f.open( QIODevice::WriteOnly ) )
{
f.write( "Ciao" );
f.close();
}
if( f.error() != QFileDevice::NoError )
qDebug() << QString("Error writing file '%1':").arg(appDataPath + "/DATABASE/Prova.txt") << f.errorString();
I also write a file that I read at startup and I can read from it so I assume the file is present and is not saved as temporary.
The output is:
D/MyApp(17849): Percorso: "/data/data/org.qtproject.example/files" dir exists: true
Now I suppose I can find my files in this directory inside the phone in this folder:
Questo PC\Samsung Galaxy J3 (2016)\Phone\Android\data\org.qtproject.example\files
But there are no directories or files inside. I bet I am missing some trivial things.
I am giving the app these permission:
android.permission.WRITE_EXTERNAL_STORAGE
android.permission.READ_EXTERNAL_STORAGE
Can someone help me?
Thanks in advance!
It seems that
QStandardPaths::AppLocalDataLocation, QStandardPaths::AppDataLocation
don't give the correct path to the app's file folder. I encountered the same issue with Qt 5.14.1. While QStandardPaths gave me
/data/user/0/com.mycompany.myapp/files
a call via a QAndroidJniObject to the java side gave me
/storage/emulated/0/Android/data/com.mycompany.myapp/files
Using the latter all directories and files were created correctly. I suggest to either try my work-around with
QtNative.activity().getExternalFilesDir(null).getAbsolutePath();
in an added java class and call it through a QAndroidJniObject or report this as a bug to Qt.
Nevertheless, there might be another solution to the problem I'm not aware of.
This code works in the simulator but not on my Android device:
local path = system.pathForFile("chinese_rules.db")
print("PATH:: " .. tostring( path ) )
When I run this code on my Galaxy S4 path returns nil.
My first thought was that it was some typo (case sensitivity) but I can't find any typo:
http://i59.tinypic.com/wlpu14.png
I can't find any reason why it should receive nil. This causes a problem as I can't load my database.
I have also tried this with the same result:
local path = system.pathForFile("chinese_rules.db", system.ResourceDirectory)
I have been able to load a path and load databases like this before.
Corona Build: 2013.2100 (2013.12.7)
Further reading the documentation I don't see that .db is a restricted file type:
Corona allows direct loading of images and audio files using the
appropriate APIs, but it has limited access to resource files on
Android using the file I/O APIs. Specifically, the following types can
not be read from the resources directory: .html, .htm., .3gp, .m4v,
.mp4,.png, .jpg, and .ttf.
http://docs.coronalabs.com/api/library/system/pathForFile.html
I found out the reason for the problem:
We are two that are working on this project and he had setup to use expansion files so two files was created (the main APK and the OBB expansion file) which I didn't notice and I only loaded the main APK file and I guess the database is in the OBB file. After setting not to use an expansion file the app works.
usesExpansionFile = false
I am trying to write a file in the internal storage directory of my application with the following step :
1) Initializing my "jni library" in Acivity Class :
MyLib mylib = new MyLib();
2) Give the internal storage path by calling getFilesDir in my Activity Class:
mylib.setSavePath(getFilesDir());
3) Call a method mylib.save() from my library which is doing the following in c++:
Open the file which i want to write with :
fp = fopen(pathtotheinternalstorage+filename,"w");
if (!fp) {
SetError(XML_ERROR_FILE_NOT_FOUND, filename, 0);
return _errorID;
}
The file path is correct : /data/data/com.myapp/files/myfile.xml
But fopen fails, i dont know what i am doing wrong.
If i write with some java code (openFileOutput), it is working well.
Thanks for your help.
More information would be helpful. Based on the path, I'm assuming you're on a Linux box. I would first check the permissions of the path. A few suggestions below
1) Try opening a file in your home directory and see if you have the same issue.
2) Try setting the file world writable using chmod 777 and see if that fixes the problem. Remember setting world writable is really INSECURE and you should change it to something more restrictive once you've found the problem.
I found the answer, i was using a library that was redefinig fopen to read inside asset folder.
#define fopen(name, mode) android_fopen(name, mode)
now it s working
I'm trying to build an Android app which makes use of the NativeActivity facility of the NDK.
I'm having the following structure:
a bunch of native shared libraries installed in /system/vendor/<company>; I'm working
with a custom built Android image so there's no problem having the libraries there with
proper permissions and everything
a couple of applications using the NativeActivity that depend in turn on the libraries
mentioned above
The libraries installed in the /system/vendor and my applications use a couple of
configuration files. There's no problem reading them using the standard C API
fopen/fclose. But those libraries and my application also need to store some files
as the result of their operation, like configuration, some run-time parameters, calibration
data, log files etc. With the storing of the files there is a slight issue as I'm not allowed to write into /system/vendor/... (as the file system under "/system/..." is mounted read-only and I do not want to hack on that).
So what would be the best way to create and store those files and where would be the
best "conforming with Android" storage area ?
I've been reading a couple of threads in the android-ndk Google group and here on SO that mention either the internal application private storage or the external SD card, but as I do not have extended experience with Android I'm not sure what would be the proper approach. If the approach involves some specific Android API a small code example in C++ would be very helpful; I've seen a couple of examples involving Java and JNI (e.g. in this SO question) but I would like to stay away from that right now.
Also there seems to be a problem with using from C++ the native activity's
internalDataPath/externalDataPath pair (a bug that makes them be always NULL).
For relatively small files(application config files, parameter files, log files etc.)
is best to use the internal application private storage, that is /data/data/<package>/files.
The external storage if it exists at all (being it SD card or not) should be used for large files that do not need frequent access or updates.
For the external data storage the native application has to "request" the correct permissions in the application's AndroidManifest.xml:
<manifest>
...
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE">
</uses-permission>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE">
</uses-permission>
</manifest>
For the internal application private storage fopen/fclose(or C++ stream equivalents if available) API could be used. Following example illustrates using the Android NDK AssetManager to retrieve and read a configuration file. The file must be placed into the assets directory inside the native application’s project folder so that the NDK build could pack them inside the APK. The internalDataPath/externalDataPath bug I was mentioning in the question was fixed for the NDK r8 version.
...
void android_main(struct android_app* state)
{
// Make sure glue isn't stripped
app_dummy();
ANativeActivity* nativeActivity = state->activity;
const char* internalPath = nativeActivity->internalDataPath;
std::string dataPath(internalPath);
// internalDataPath points directly to the files/ directory
std::string configFile = dataPath + "/app_config.xml";
// sometimes if this is the first time we run the app
// then we need to create the internal storage "files" directory
struct stat sb;
int32_t res = stat(dataPath.c_str(), &sb);
if (0 == res && sb.st_mode & S_IFDIR)
{
LOGD("'files/' dir already in app's internal data storage.");
}
else if (ENOENT == errno)
{
res = mkdir(dataPath.c_str(), 0770);
}
if (0 == res)
{
// test to see if the config file is already present
res = stat(configFile.c_str(), &sb);
if (0 == res && sb.st_mode & S_IFREG)
{
LOGI("Application config file already present");
}
else
{
LOGI("Application config file does not exist. Creating it ...");
// read our application config file from the assets inside the apk
// save the config file contents in the application's internal storage
LOGD("Reading config file using the asset manager.\n");
AAssetManager* assetManager = nativeActivity->assetManager;
AAsset* configFileAsset = AAssetManager_open(assetManager, "app_config.xml", AASSET_MODE_BUFFER);
const void* configData = AAsset_getBuffer(configFileAsset);
const off_t configLen = AAsset_getLength(configFileAsset);
FILE* appConfigFile = std::fopen(configFile.c_str(), "w+");
if (NULL == appConfigFile)
{
LOGE("Could not create app configuration file.\n");
}
else
{
LOGI("App config file created successfully. Writing config data ...\n");
res = std::fwrite(configData, sizeof(char), configLen, appConfigFile);
if (configLen != res)
{
LOGE("Error generating app configuration file.\n");
}
}
std::fclose(appConfigFile);
AAsset_close(configFileAsset);
}
}
}