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Developer
Posts: 133
Registered: ‎03-28-2011
My Device: BlackBerry 9900 & PlayBook
My Carrier: Bell

Re: Cascades only for BB10 and not for Playbook?

Hi guys

 

So what I've been hearing is that there is a definite plan in place to have the PlayBook use the same BB10 OS, once it launches. It likely won't be on the same day, but shortly after. At that time, you can use Cascades. 

 

While alopix has done great work to get Cascades running, I probably wouldn't recommend it. As he's seen, you run into resolution issues, and also the fact that Cascades is fairly incomplete at this point. 

 

I would recommend that you use Qt and QML for now while we wait for Cascades to mature and become available. To get BB10 style controls, you can check out my project here and help me convert these controls for use on the PlayBook. 

https://github.com/taab-co/qml-cascades

 

I'm still working on it, but I'm making really good progress. Right now, it's dedicated to Dev Alpha resolutions, but I will adapt it for PlayBook resolutions some time this week since I need it too. 

 

But the more help I get, the faster everything goes. 


Founder of Pulsecode Inc. and taab
Authomator - Two-factor authentication codes on BlackBerry 10 - http://www.xitijpatel.com/ - Follow @xitijpatel
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Developer
Posts: 1,807
Registered: ‎04-28-2009
My Device: Z10 (STL100-4)-10.3.2.858, Z10 (STL100-3)-10.3.1.2576, Z30 (STA100-5)-10.3.1.2582, Passport (SQW100-1)-10.3.1.2576, PlayBook (16GB)-2.1.0.1917
My Carrier: Verizon

Re: Cascades only for BB10 and not for Playbook?

alopix: I followed your instructions, the app opens up but then closes immediately. No error, message, error code, etc.

---Spends time in #blackberrydev on freenode (IRC)----
Three simple rules:
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2. "Like" posts that you find helpful.
3. If a solution has been found for your post, mark it as solved.
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Developer
Posts: 1,807
Registered: ‎04-28-2009
My Device: Z10 (STL100-4)-10.3.2.858, Z10 (STL100-3)-10.3.1.2576, Z30 (STA100-5)-10.3.1.2582, Passport (SQW100-1)-10.3.1.2576, PlayBook (16GB)-2.1.0.1917
My Carrier: Verizon

Re: Cascades only for BB10 and not for Playbook?

Ok, figured it out. Instinctually thought that "<env var="LD_LIBRARY_PATH" value="app/native/lib:/usr/lib/qt4/lib"/>" should be commented out. Didn't see the reference to app/native/lib. Re added that and it worked.
---Spends time in #blackberrydev on freenode (IRC)----
Three simple rules:
1. Please use the search bar before making new posts.
2. "Like" posts that you find helpful.
3. If a solution has been found for your post, mark it as solved.
--I code too much. Well, too bad.
Trusted Contributor
Posts: 117
Registered: ‎02-29-2012
My Device: PlayBook & Nexus 4

Re: Cascades only for BB10 and not for Playbook?

[ Edited ]

@alopix: I read the instructions on your blog. Qt4 libs must be packaged with the app for the Cascades app to run under OS 2.x. As Qt4 licenses are either commercial or LGPL, this is fine for a test but obviously not a solution for a developer. But if the Qt4 libraries are to be provided with BB10, I think RIM will need to negotiate a deal with Nokia as they are competitors in the smartphone and tablet markets. I wonder if this is even possible. What do you think?

Developer
Posts: 426
Registered: ‎04-10-2011
My Device: Z30

Re: Cascades only for BB10 and not for Playbook?

My solution currently is only to show, that it's possible to run Cascades on the PlayBook - even if RIM doesn't provide us with an official version yet Smiley Wink
This is of course nothing you would use for production purposes and therefor the license shouldn't be a problem.
As soon as RIM officially releases Cascades for the PlayBook, there won't be any licensing issues because we will just link to the Qt version available on the PlayBook. In addition, I don't see a problem with Qt's LGPL: according to this license, compiling or linking software with the product under the LGPL won't be affected by the license. This means: distributing object code is not a problem, as long as the source code of Qt is still available and you tell your users that.

I guess that's why it's no problem for RIM to just install the Qt libraries on the BB10 or later PlayBook devices. The LGPL is just great for that Smiley Very Happy
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New Developer
Posts: 29
Registered: ‎02-26-2012
My Device: Playbook, Bold 9900
My Carrier: Telus

Re: Cascades only for BB10 and not for Playbook?

Not sure why RIM would have to negotiate a deal.  Qt is Open Source licensable under the LGPL.  RIM is free to develop and redistribute Qt as long as they abide by the terms of the license. There are lots of LGPL libraries used on the playbook.  Go to http://worldwide.blackberry.com/legal/thirdpartysoftware.jsp or look in about/general/legal on the settings page for your playbook.

 

(Disclaimer: I am not a lawyer)

Trusted Contributor
Posts: 117
Registered: ‎02-29-2012
My Device: PlayBook & Nexus 4

Re: Cascades only for BB10 and not for Playbook?

[ Edited ]

Guys, I am just playing the devil's advocate here. The BlackBerry PlayBook device and QNX software are commercial products. QNX and the derived BlackBerry Tablet OS and BB10 are neither available under the GPL nor open source. I don't see how the Qt4 libs could be included in, and distributed with, a commercial, non open source OS free of charge. If this is allowed then any commercial software developer can do the same. This works on Linux as Linux is open source software. But then I am not a lawyer so I must be missing something.

Developer
Posts: 426
Registered: ‎04-10-2011
My Device: Z30

Re: Cascades only for BB10 and not for Playbook?

Don't confuse the LGPL with the GPL. They are similar, but also completely different.
The GPL is viral, which means that works based on something licensed under the GPL has to be released under the GPL too. The LGPL is made for libraries just like Qt and only requires modifications of the LGPL-product to be licensed under the LGPL again.
Linking to a library under the LGPL is possible for open source projects as well as closed source projects (even if you sell the product). This doesn't affect packaging Qt on the PlayBook/BB10 devices. RIM is only required to give back the (new) Qt source if they change something, but are not required to pay anything. That's the beauty of Open Source Software ;D
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Trusted Contributor
Posts: 117
Registered: ‎02-29-2012
My Device: PlayBook & Nexus 4

Re: Cascades only for BB10 and not for Playbook?

I see. Qt for BlackBerry is part of the "official Qt  distribution" so the LGPL thing works. For some reason I thought that it was a custom build by RIM, like Mono for iOS or Android by Xamarin. Cheers!

Developer
Posts: 426
Registered: ‎04-10-2011
My Device: Z30

Re: Cascades only for BB10 and not for Playbook?

Qt for the PlayBook started out as a fork by RIM (https://github.com/blackberry/Qt) and is now part of the official up-stream source of the Qt project.
Even if it were a custom build (like it was before), it would still be possible, as long as RIM publishes the source code.
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Check out my apps in the BlackBerry World
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