Does qt support serialport in android system ?

peterlin82

Android Qt 5.2 SerialPort support added
http://www.kdab.com/qt-on-android-episode-1/?utm_source=rss&utm_medium=rss&utm_campaign=qt-on-android-episode-1

JKSH

The blog post spoke too soon. It won't be ready for Qt 5.2 after all: https://codereview.qt-project.org/#change,70618

liangliang

after read
https://codereview.qt-project.org/#change,70618 i am confused ,
so i want to make the question clear :

in https://codereview.qt-project.org/#change,70618 said that now
qt have support serial port for android ,right ?
but the fact is ,now qt do not support serial port for android , right ?

and where can i download the newest patch if you upload qt code.

thanks very much !
[quote author="JKSH" date="1383827868"]The blog post spoke too soon. It won't be ready for Qt 5.2 after all: https://codereview.qt-project.org/#change,70618[/quote]

JKSH

[quote author="liangliang" date="1383877061"]in https://codereview.qt-project.org/#change,70618 said that now
qt have support serial port for android ,right ?[/quote]No. After I read Bogdan's blog post, I submitted that patch to update the documentation, to say that Android is supported.

However, in the comments below, Laszlo said it's not supported properly yet. So, the patch was not accepted.

[quote]but the fact is ,now qt do not support serial port for android , right ?[/quote]Right.

[quote]and where can i download the newest patch if you upload qt code.[/quote]From the same codereview page. Scroll down until you see "Download".

If you want to apply these patches, you will need to download the git repository, apply the patch, and then compile all of the Qt libraries yourself: http://qt-project.org/wiki/Building_Qt_5_from_Git

peterlin82

I don't find any information about QSerialPort in android.

http://doc-snapshot.qt-project.org/qt5-stable/topics-network-connectivity.html#serial-port-communication

http://qt-project.org/wiki/New-Features-in-Qt-5.3

Does Qt 5.3.0 support serialport in android system?

kuzulis

@peterlin82,

no. it is still in "experimental" support, only for the rooted devices. You should take and re-build QtSerialPort from sources from Git.

liangliang

@ kuzulis ,
I take and re-build Qt source from Git successful.

http://qt-project.org/wiki/building_qt-android_on_windows

then I root my phone.
i use the demo named master in serialport examples to test

then i found that i can not open device
here is the error log .

W/Qt (25097): qserialport_unix.cpp:94 (QString serialPortLockFilePath(const QString&)): The following directories are not readable or writable for detaling with lock files
W/Qt (25097):
W/Qt (25097): qserialport_unix.cpp:96 (QString serialPortLockFilePath(const QString&)): /var/lock
W/Qt (25097):
W/Qt (25097): qserialport_unix.cpp:96 (QString serialPortLockFilePath(const QString&)): /etc/locks
W/Qt (25097):
W/Qt (25097): qserialport_unix.cpp:96 (QString serialPortLockFilePath(const QString&)): /var/spool/locks
W/Qt (25097):
W/Qt (25097): qserialport_unix.cpp:96 (QString serialPortLockFilePath(const QString&)): /var/spool/uucp
W/Qt (25097):
W/Qt (25097): qserialport_unix.cpp:96 (QString serialPortLockFilePath(const QString&)): /tmp
W/Qt (25097):
W/Qt (25097): qserialport_unix.cpp:96 (QString serialPortLockFilePath(const QString&)): /data/local/tmp
W/Qt (25097):
W/Qt (25097): qserialport_unix.cpp:197 (bool QSerialPortPrivate::open(QIODevice::OpenMode)): Failed to create a lock file for opening the device

Can anyone tell me how to do with it . and how to get open device permission .

kuzulis

bq. Can anyone tell me how to do with it . and how to get open device permission .

Seems, you should to run your application as superuser.

PS: Now is in process an attempt to implement support of QtSerialPort for non-rooted Android devices : https://codereview.qt-project.org/#change,83480

But I do not know when this solution will be completed. So, need for waiting only. :)

liangliang

@ kuzulis
thanks , but i have no idea how to run my application as superuser , can you give me some tips ?

kuzulis

@sudo <path/to/my/app>@

no?

liangliang

@ kuzulis ,
my computer is win7 system, and i use qtCreator to deploy application
afer google , some people give some advise :

QT Creator switch to Projects > "Run Settings" > "Run configuration:"
select "custom executable"
Executable: sudo /d4/workspace/qt/test2-build-desktop/test2
change the above line to match your project path

i did these steps .
sudo E:/QT5.3_beta_code/serialport/build-master-Android_for_armeabi_v7a_GCC_4_7_Qt_5_3_1-Debug

then some errors occured.
*sudo E:/QT5.3_beta_code/serialport/build-master-Android_for_armeabi_v7a_GCC_4_7_Qt_5_3_1-Debug
can not be found in the path. *

these step is right ? i am not so familiar with sudo command , i don‘t know if i do the right command.

thanks!

kuzulis

To be honest, I don't know how to do it from QtCreator.

mr_wallyit

@lab Rat
I have build QtSerialport with the library 5.3.0 but i have always equal message.

The device is unblocked because if i use serial-java i can open the port.

thanks.

mr_wallyit

sorry, I am new in this forum

phyatt

I put some time into getting Qt + Android + QtSerialPort to work from a windows computer. I wrote a blog post about how I went about it. It works really well when it was all done.

I also needed to do my own JNI calls, too, so I ended up copying the UsbJNIActivity and inserting my own code.

http://phyatt.t15.org/wp/2015/04/qt-android-serial-port/

Hope that helps.

Hello_ZB

If you're going to connect the FTDI chip, then you can approach this sample https://github.com/HelloZB/QtAndroidFTDI (no need root device).