I promised 2 new course modules for February and just published the second one. In case you don't recall I discussed the first one here and it covered building Codename One applications from the open source code.
This new module goes through seven lessons that cover everything you need to know when building a performant app. It covers everything from generic performance tips/analysis all the way to profiling and a case study. You can check out the full module in the Deep Dive into Mobile Programming course in the academy.
I promised 2 new course modules for February and just published the first one. It covers the process of building a Codename One app from the Codename One source code. The whole process is done without using the Codename One plugin or build servers. It uses only open source project code to deliver iOS/Android & desktop binaries!
You can check out the full module in the Deep Dive into Mobile Programming course in the academy.
One of the big issues with some new users who picked up Codename One was the lack of up to date device skins. We made several attempts in the past to improve this situation but these ended up as half measures at best. Last week we addressed some of the core problems that made it hard to add new skins and as a result we now have 33 new skins that are far better than anything we had before.Read More
Device only bugs are the worse. You need to go through a device build and reproduce/rinse/repeat. Thankfully these bugs are rare but sometimes they just hit you smack in the face. One such problem occurred when I was debugging a transition on Android related to a login form. I would move between a Form where I had the keyboard open to one where it was closed. This created a nasty effect where the keyboard folded leaving a black space and the transition played out about that black space.Read More
Last week we discussed the first part of working with text components and left some big tasks for this week. This week we'll try to address the remaining issues with text input and make it easier to construct UI's. This is crucial as we'll be going into code freeze soon and we need enough time to iron out the issues in the text input.Read More
I started working on this post back in August and so much happened in between I just had to scrap the whole thing and start over again... I've discussed buttons before and now it's time for
TextArea. But before we go into that lets take a moment to talk about the problems that arose from the last installment of pixel perfect.
Offline build is a pretty complex topic which is why we opted for the online build process in Codename One. It allows for simple install/build and doesn't require a Mac. However, if you work for a bank or a government agency using a cloud solution is sometimes an insurmountable roadblock. That's why we introduced the offline build option to replace our old private cloud option.Read More
Continuing the trend I revisited the old crash protection video in the "how do I" section and updated it with current information and details. The old video still featured an old flag that should be avoided...
The new video is relatively short and simple as the feature isn't very complex, I hope to produce several more of these and bolster the video section further.
I already have half a post on text components but I've put that on hold for now as I've been working on the on-top side menu to supersede the existing side menu bar implementation. I've made some fixes for it over the week, I wanted to make it the default for Codename One apps but it still isn't "perfect". We will make it the default within the next couple of weeks so please test it after this weeks update and let us know ASAP if you spot any issues!Read More
I redid the include source tutorial which was really old by now and included some outdated "facts" while missing key information. Include source allows us to get the native OS project source code on build, this allows us to debug and profile on the devices.Read More
I haven't blogged as much in the past month and as a result I have a big pile of updates from all over. This is going to be a big list so I'll start with a few pull requests that were submitted by Diamond and Durank. If you see something broken or something that could be better in Codename One just fix it like they did!Read More
Last week I wrote about the effort of revitalizing the native themes in Codename One and I'm not sure if I got the point across as I would have liked it. So this week before I go into the changes and work we're doing I'd like to take a step back and explain how everything works and why we need a native theme...Read More
I've mentioned before that our biggest priority in 3.8 is refining the UI design of Codename One applications. This is a difficult task as it is so vague. There are so many small things we can do, when they are viewed in unison they seem approachable but as we start going thru the tasks priorities muddle. That's why we need feedback from you guys on what bothers you about the UI and its refinement.Read More
Push gets a lot of support queries, it's a hard subject to wrap your head around especially with all of the conflicting and shifting landscape around it. To make matters worse every OS conceptualizes it very differently. I go into some of the really advanced stuff such as fallback behavior in the advanced course but basic stuff is still a crucial first step.Read More
Fingerprint scanners are pretty common in modern hardware both from Apple and some Android vendors. The problem is that the iOS and Android API's for accessing them are a world apart. However, it's possible to find some low level common ground which is exactly what our cn1lib for fingerprint scanning accomplished.Read More
The bootcamp is winding down and I'm finally back to our usual scheduled posts. I'd like to open with a common practice that isn't nearly documented enough: use the native main/EDT threads. Our EDT serves many purposes but one of it's biggest roles is portability. By having an EDT we get consistent behavior across platforms.Read More
We use intercom.io for our website support system you can see it as the chat button on the bottom right of the page. The true value of this tool is in it's ability to deliver a unified interface everywhere, normally this stretches into native mobile apps as well. As a result we decided to port the native intercom device API to Codename One so it will be easy to deploy everywhere.Read More
Continuing our security trend from the past month we have a couple of new features for Android security that allow us to block the user from taking a screenshot or copying & pasting data from fields. Notice that these features might fail on jailbroken devices so you might want to check for jailbreak/rooting first.Read More
When Android launched RSA1024 with SHA1 was considered strong enough for the foreseeable future, this hasn't changed completely but the recommendation today is to use stronger cyphers for signing & encrypting as those can be compromised.Read More
iOS & Android are walled gardens which is both a blessing and a curse. Looking at the bright side the walled garden aspect of locked down devices means the devices are more secure by nature. E.g. on a PC that was compromised I can detect the banking details of a user logging into a bank. But on a phone it would be much harder due to the deep process isolation.Read More
Auto-renewable subscriptions provide, arguably, an easier path to recurring revenue than non-renewable subscriptions because all of the subscription stuff is handled by the app store. You defer almost entirely to the app store (iTunes for iOS, and Play for Android) for billing and management.Read More
Non-renewable subscriptions are really the same as consumable products, except that they are shareable across all of a user's devices. Auto-renewable subscriptions, on the other hand, will continue as long as the user doesn't cancel it. They will be re-billed automatically by the appropriate app-store when the chosen period expires, and all management of the subscription is handled by the the app-store itself.Read More
In-app purchase is ahelpful tool for making app development profitable. Codename One has supported in-app purchases of consumable and non-consumable products on Android and iOS for some time now, and with the next update we are adding support for subscriptions. For such a seemingly simple task, in-app purchase involves a lot of moving parts - especially when it comes to subscriptions.Read More
The Phoenix UI kit by Adrian Chiran is one of the best looking and most challenging template UI's I had to adapt in recent history. The breadth of the design is pretty challenging but it also has some elements that are really hard to adapt across platforms in a portable way.
In the previous template post I introduced a material design inspired theme. This time the theme I chose is simpler "cleaner" but not necessarily easier to integrate. I've had quite a few difficulties wrestling with Photoshop oddities (bugs?) that made this template painful, hopefully I've narrowed down the process enough so this should become easier.Read More
We get contacted quite a bit about the prospect of porting applications that were already written using the Android API. In this quick tutorial we will walk you thru the paces of converting a simple Android application to a Codename One application. We will also start with some basic tips covering the differences between Android and Codename One development.Read More
Generating a template from a PSD isn't hard but it isn't a trivial task either, in this recurring segment I will try to generate good looking Codename One templates from freely available PSD files. Since this requires some effort I don't think I'll be able to keep this as a weekly segment but I'll try to post such a template once every two or three weeks. If you know of a free PSD that you'd like to see as a Codename One app point me at it in the comments and I might integrate it in a future post!Read More
Google Play Services is a proprietary set of tools that Google licenses to vendors under limited conditions. In recent years more and more features go into Google Play Services making it harder to build an app without it.Read More
There are many Codename One resources for building native mobile apps but they are often all over the place, in this blog post I'll try to concentrate the best resources for people who already know Java and are looking to pick up Codename One. If you don't know Java yet please check out this post where we discuss resources for beginners to Java.Read More
A few years back I wrote an article for O`Reilly covering the advantages of cross platform over native OS code. Almost 3 years have passed and a lot has changed in our industry so I wanted to re-examine how this impacts my perspective on cross platform vs. native.Read More
We often build one app and sell it to multiple customers. After all, most customers ask for similar things with minor changes. E.g. if I build a restaurant app and then sell it to one establishment I can then resell it to another with almost no change at all...Read More
The material design floating action button is a powerful tool for promoting an action within your application. Quite a few Codename One developers implemented with own interpretation of this UI element and with the coming update we will have an official implementation.Read More
When we designed the icon for the new Kitchen Sink demo we tried to use material design principals. We thought it would look reasonable on iOS but it looked awful. So we decided to adapt the design and create a separate yet similar icon for iOS.Read More
If you relied on the
android.newPeer build hint it will no longer be available starting with this update. When you build for 3.5 you will still get the old behavior if you define that hint but otherwise it will be ignored. This is a precursor step to merging the newPeer branch into the main branch. It's an important step to help us move forward with one code base!
One of the biggest changes we made in the past couple of years was the introduction of Java 8 language support features and making it the default target. We are now ready for the next step...Read More
One of the first Codename One performance tips is: "Don't use gradients". We already wrote about improved performance to gradients in the past but that covered linear gradients and didn't cover radials on iOS.Read More
A couple of years ago at Google IO one of the prominent speakers turned to the audience and asked them: "Raise your hands if you understand the activity lifecycle". He then proceeded to call them "liars", claiming that after all his years at Google he still doesn't get it properly...Read More
Starting with the next Friday release we will migrate to the new peer support. This migration will allow us to focus on a single code base and remove the branch where we are maintaining the old peer support.Read More
We finished the final major piece of the offline build offering that we announced in July!
This Sunday we will update the plugins to include this ability as an option. Once installed you can use the instructions below to install the offline build service.
Millions of Codename One apps are installed on devices every month. Most of them aren't in the gallery and are never featured in this recurring segment. We are looking for something exceptional in apps that we feature here and Ana Paltel fits that bill. It has a very polished UI and it is shipped by a major operator. It uses some unique Codename One features to boot making it even more interesting.Read More
As we mentioned recently we have a new idea on how peering can be improved and we just deployed a this into our build servers in the weekend update. This is highly experimental and might crash instantly which is why we hope you give it a test drive and see how it feels before we switch it on by default.Read More
I blogged about peer components all the way back in 2014 trying to explain basic facts about their limitations/behaviors. A lot of those limitations are inherent but over the past year or so we've been thinking more and more about the z-order limitation.Read More
A common issue we get from developers relates to minor differences between devices which are often very hard to quantify. They are also very hard to explain to the developers in some occasions. One of the biggest points of difficulty is density which is a very hard concept to grasp and it's often hard to know which image will be used from the set of multi images or how many pixels will be used for 1 millimeter.Read More
Background fetch allows an app to periodically "fetch" information from the network while the app is in the background. This is scheduled by the native platform, where apps that support background fetch will be started up (in the background), and their
performBackgroundFetch method will be invoked.
Debugging Codename One apps on iOS devices has been documented well with a video for years, we didn't spend too much time outlining the Android counterpart mostly because we didn't really use it as much and it was far simpler.Read More
Bluetooth is one of those specs that makes me take a step back... It's nuanced, complex and multi-layered. That isn't necessarily bad, it solves a remarkably hard problem. Unfortunately when people say the words "bluetooth support" it's rare to find two people who actually mean the same thing!Read More
We're all pretty jaded when it comes to software but when I first saw yHomework I was completely floored by it!
Where was this tool when I was in junior high?
If you haven't seen yHomework in action I suggest you give it a try right now on your Android or iOS device.
We talked about the new Android 6 (Marshmallow) permissions in Codename One last week and so far we've been pretty happy with the result. We had some build regressions on the older Ant based build path but those were fixed shortly after and it's been smooth sailing since then. As part of the transition to the new permissions system we added two features to the simulator and the
Pumpop is a social networking app in the spirit of tinder that is available globally and installed on many devices all over the world. One of its major draws is it's portability which will soon extend to Windows Phone as well.Read More
Up until Marshmallow (version 6) Android used a rather obtuse permission system that very few end users understood. With API level 23 (Marshmallow) Android finally shifted to a structure that makes more sense similarly to iOS. Marshmallow asks a users permission the first time an API is used e.g. when accessing contacts the user will receive a prompt whether to allow contacts access.Read More
With the latest version of the Android port we fixed a long running bug in gradient drawing on Android. Gradients should now work correctly and will also be performant potentially even faster than images on Android. Our standing recommendation is to avoid gradients as they pose a memory/performance penalty on most platforms and so this change raises the question of using gradients back into the forefront.Read More
The jat app is very similar to whatsapp in some regards but is more oriented towards group communication than SMS replacement. Over the past couple of weeks we picked it up as a great communication tool in our team. It uses push notifications to notify and activates accounts via SMS. This makes it very convenient for someone like myself who moves between devices constantly.Read More
As part of our continuing effort to squash bugs for the 3.4 release date we hit two major issues, the first of which is a long time RFE to fix PDF viewing on iOS and Android to work consistently. This also applies to any file opening in iOS/Android which should now be trivial with the
Display.execute method. Just use that method on any file within your home directory in
FileSystemStorage and it should launch the native app to view that file.
When we first started to present Codename One to investors a very prominent local investor said he'd commit to a round of funding if we allow Android developers to import native Android apps to Codename One. We passed on that which in retrospect might have been a mistake but the technical challenges were the main reason for that decision.Read More
Starting with the next update of Codename One (later this week) we will switch
Toolbar on as the default for all newly created projects. This doesn't mean much for most of us as existing projects won't be affected, however if you are creating a new project this means you won't need to create a
Toolbar for every
Form and that we won't have to deal with as many issues related to the native Android title.
We are trying to improve the visibility of Codename One within search engines and as part of that we think we can also help you guys improve your visibility. When you submit your apps to the app gallery we provide dofollow links to your website/app store listings. We'd appreciate if you place dofollow links back to https://www.codenameone.com/ which you can place in a very hidden/unobtrusive way. This helps us increase our page rank and as a result will improve your page rank as we link back to you.Read More
I've been remarkably busy working on issues and documentation so I neglected an important announcement I had to make. Over the weekend we flipped the default build from gradle back to ant. So effectively if you don't set any build hint the behavior will be
android.gradle false which should work fine for most of you. This is temporary but we felt it was necessary as a stopgap measure.
I had a big post ready for today but after a long twitter debate with @BrendanEich I had to write a followup as twitter is a poor medium for that level of debate.
This started with a blog post from Andreas Gal who effectively took the exact opposite stance to mine on Google's move to OpenJDK.
Then Mr. Eich picked it up...
We released a new version of the introducing Codename One video almost a month ago but we just neglected to highlight it in the blog. Our old videos are pretty dated by now and we use far better toolchains for video production today, so we are in the process of redoing all our old videos. This is a long and tedious process that we do while producing newer content, fixes and moving forward. So the timeline of such updates is quite volatile. Check out the new video below.Read More
Historically, we didn't use Androids profiling tools often. They were pretty awful and the only tools that we really used extensively were the on-device GPU profiling tools which were reasonably good. In recent years Android's native story improved by leaps and bounds with the introduction of Android Studio and 3rd party tools developing native Android apps has improved a lot. But the CPU profiling tools are still stuck in the stone age and this is in stark contrast to the iOS tooling.Read More
We became infatuated with icon fonts a while back and used them quite a bit, recently we added the FontImage class that made them really easy to use.
However, up until now you had to download a font. Look up the value and enter it in. This was OK but not ideal in terms of syntax/availability especially for simpler apps.
Today we dealt with some push messages overloading our servers, some of the apps developed in Codename One are remarkably successful and as a result our push servers got bogged down.
To mitigate that and prevent service interruptions we moved all push activity to the new servers, this effectively means that a push operation on the old servers will map to the new servers seamlessly. This also means that we no longer support the null push target even for the old push servers. Its just too expensive to support on scale of 150M+ devices.
While its pretty easy to use native interfaces to write Android native code some things aren't necessarily as obvious. E.g. if you want to integrate a 3rd party library, specifically one that includes native C JNI code this process is somewhat undocumented. If you need to integrate such a library into your native calls you have the following 3 options:Read More
Chen was working with a customer that needed some specific ad network support and decided to open source some of that work. We now have integration with Flurry both for its ads and analytics support both of which are pretty cool and have some distinct advantages over the current Google equivalents.Read More
Codename One provides a rich set of drawing primitives in its Graphics class. It allows you to draw text, shapes, and images to the screen. The position where these elements will be rendered is determined based on a combination of Graphics state information (e.g. the current translation, and transform) and coordinates that are passed to the drawing method. Understanding how these coordinates are calculated can be tricky when you first begin using the API.Read More
One of the pains in Codename One is the access to the demos, yes we have the downloadable demo bundle and the SVN but for a compete novice to Codename One this isn't front and center. Chen decided to address that by embedding the latest versions of the demos both into the Eclipse and the NetBeans plugins, now when you create a new Codename One project you can also create a demo project and "just run it". This allows you to quickly learn/debug our sample code which should help with the Codename One learning curve.Read More