Qt Mobile Application for Android
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@divaindie basically we can add only binary files into qrc. during compilation of Qt application ,qmake will create a file called qrc_application.cpp file from .qrc file .
.this qrc_application.cpp will have pointers to binary dump of resources which are added into .qrc file before building .This link will explain more about qrc system in Qt http://doc.qt.io/qt-5/resources.html
suppose if we include a database file(which is not a binary file) into .qrc ,it will not work because "The database name is just the path to the file. Qt does not intercept the file name but hands it over directly to the SQLite functions (by calling toUtf8() on the “path”), which in turn try to open that file – and will eventually fail, of course."
You can find this in below qt forum thread
https://forum.qt.io/topic/3949/sqlite-database-in-project/3This is the reason why I found in-memory database is the solution to my problem .If you see this link you will get why I had choosen in-memory database
https://stackoverflow.com/questions/4254250/embedded-database-in-qt
But I don't know how to do it .If you have the solution /or any alternative solution let me know@divaindie have you tried it this way ? https://stackoverflow.com/a/40713888/135559
or this: https://forum.qt.io/topic/94088/deploy-sqlite-database-with-apk/12
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@divaindie have you tried it this way ? https://stackoverflow.com/a/40713888/135559
or this: https://forum.qt.io/topic/94088/deploy-sqlite-database-with-apk/12
@ekkescorner i tried the link https://forum.qt.io/topic/94088/deploy-sqlite-database-with-apk/12
but i got below error message while copying db file to a writable location ( i.e QStandardPaths::writableLocation(QStandardPaths::StandardLocation::AppDataLocation); )
W QtMainThread: type=1400 audit(0.0:119): avc: denied { link } for name="qt_temp.xajbeT" dev="dm-0" ino=124288 scontext=u:r:untrusted_app_25:s0:c512,c768 tcontext=u:object_r:app_data_file:s0:c512,c768 tclass=file permissive=0
edit1 : it works if i use "QStandardPaths::GenericDataLocation" instead of "QStandardPaths::StandardLocation::AppDataLocation".
now my question is which location i should prefer using to copy my database file from assets:/ folder ? .(FYI both read/write opearion allowed on database file) -
@ekkescorner i tried the link https://forum.qt.io/topic/94088/deploy-sqlite-database-with-apk/12
but i got below error message while copying db file to a writable location ( i.e QStandardPaths::writableLocation(QStandardPaths::StandardLocation::AppDataLocation); )
W QtMainThread: type=1400 audit(0.0:119): avc: denied { link } for name="qt_temp.xajbeT" dev="dm-0" ino=124288 scontext=u:r:untrusted_app_25:s0:c512,c768 tcontext=u:object_r:app_data_file:s0:c512,c768 tclass=file permissive=0
edit1 : it works if i use "QStandardPaths::GenericDataLocation" instead of "QStandardPaths::StandardLocation::AppDataLocation".
now my question is which location i should prefer using to copy my database file from assets:/ folder ? .(FYI both read/write opearion allowed on database file)@divaindie what's your Qt version ?
there were issues with temp files causing errors while copying on Android
5.10.1 and 5.11.1 should be ok -
@divaindie what's your Qt version ?
there were issues with temp files causing errors while copying on Android
5.10.1 and 5.11.1 should be ok -
@ekkescorner iam using 5.10.1 !!! .which version of Qt works fine for developing Android applications?
@divaindie 5.10.1 should be fine.
can you create, save and copy a normal text file at your AppDataLocation ? -
@ekkescorner Iam able to create files.but i cant read/write/copy files to AppDataLocation
@divaindie curios.
I'm using this to get the appdata locationmDataRoot = QStandardPaths::standardLocations(QStandardPaths::AppDataLocation).value(0);then I'm checking if the directory exists, but this should exists on Android, but must be created on iOS
to be safe I'm always checkingQDir myDir; bool exists; exists = myDir.exists(mDataRoot); if (!exists) { bool ok = myDir.mkpath(mDataRoot); if(!ok) { qWarning() << "Couldn't create mDataRoot " << mDataRoot; return false; } qDebug() << "created directory mDataRoot " << mDataRoot; }then as next I'm creating a /data/ directory and place all my other files ond folders inside this
never had problems with read write delete copy -
@divaindie curios.
I'm using this to get the appdata locationmDataRoot = QStandardPaths::standardLocations(QStandardPaths::AppDataLocation).value(0);then I'm checking if the directory exists, but this should exists on Android, but must be created on iOS
to be safe I'm always checkingQDir myDir; bool exists; exists = myDir.exists(mDataRoot); if (!exists) { bool ok = myDir.mkpath(mDataRoot); if(!ok) { qWarning() << "Couldn't create mDataRoot " << mDataRoot; return false; } qDebug() << "created directory mDataRoot " << mDataRoot; }then as next I'm creating a /data/ directory and place all my other files ond folders inside this
never had problems with read write delete copy@ekkescorner this worked for me.thanks!!.
for linux & windows if i want to add my database file what changes i need to make in .pro file ?.
for android i made below changes.
android
{
my_files.path = /assets
my_files.files = $$PWD/android/*
INSTALLS += my_files
} -
@ekkescorner this worked for me.thanks!!.
for linux & windows if i want to add my database file what changes i need to make in .pro file ?.
for android i made below changes.
android
{
my_files.path = /assets
my_files.files = $$PWD/android/*
INSTALLS += my_files
}@divaindie good to hear that it's working for you
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@ekkescorner this worked for me.thanks!!.
for linux & windows if i want to add my database file what changes i need to make in .pro file ?.
for android i made below changes.
android
{
my_files.path = /assets
my_files.files = $$PWD/android/*
INSTALLS += my_files
}@divaindie said in Qt Mobile Application for Android:
for linux & windows if i want to add my database file what changes i need to make in .pro file ?
Maybe it'd be good you mark this post as solved since you originally asked for Android and it's working for you now, and open a new post for the other platforms so not to hijack the post. Thanks.
