Using B4A On The Kindle Fire & The Amazon App Store Tutorial Version 1.0 This tutorial is being written to help notify/guide B4A users of known issues that have been found using B4A with the kindle fire device and some possible work arounds. There have been many questions about using B4A on the kindle fire and we hope to clear up some of the confusion there has been about this device. First off it seems that most all issues are with the display and scaling for this device. Their forked version of Android Gingerbread has some strange things that you would not expect to see. The following text and images will guide you through the things we found when converting a number of Apps to be used on the kindle fire. The kindle fire device has the following hardware for the display. *Width: 600px *Height: 1024px Abstracted LCD Density: 169 Target: Android 2.3.4 - API Level 10 RAM: 512 MB *Note: The device will reserve 20px to display a soft key menu, making the effective portrait resolution 1004px high x 600px wide and the effective landscape resolution 580px high x 1024px wide. This is only true if your app is set to display full screen. Page: 1
EditText on the kindle fire The first issue found is the way their forked version handles the EditText of B4A and I would assume any other programming language. I took an App that has been used on many other Android devices and the EditText has always had the same look and function on these other devices! They have all been consistent in the way they worked and functioned. This IS NOT the case with the kindle fire. The device we are testing on, has the latest OS update as of this writing. The image below has vertical red lines that are offset by one pixel and each offset line is ten pixels high. In the top image you can see the EditText boxes look normal. The same code was then used on the kindle fire and the second image is the result. Not GOOD. So it is easy to see with this one issue, how your App would be rejected for use on the kindle fire. If you study the image above you can see by the red markers placed on the image, that the other devices show an EditText height of 40 pixels, and this is correct. Now looking at the kindle fire, you can see the EditText height is only 30 pixels high, even though it was set to be 40. Now, looking again at the bottom image you can also see that the Buttons are about 7 pixels smaller than on the Samsung Tablet. Again, this is the same code running on both devices. Page: 2
The markers used were created in PhotoShop. Each line is one pixel wide and each offset line is ten pixels tall. See the following image below: Each block is 10 pixels high Overall height is 40 pixels The labels seem to be OK but it is the Buttons and the EditText boxes that seem to have the issues. So, your button must be made seven pixels larger that you want them to be and the EditText must be ten pixels larger than required. The direction of the size error is also not the same for the two objects. The EditText is center issued, while the Buttons are bottom issued. Meaning, the EditText should have the top position set to -5 pixels for the Top position and the Height should be set to 10 pixels higher than desired, while the Buttons should use the same Top position and be made 7 pixels taller in height. This makes it a little more difficult to modify your code for the kindle fire device as each object acts different. Data Directories & Path On The kindle fire The kindle fire device does not have a SDCard memory slot, however, it does have an internal SDCard card. The default path on the device is: /mnt/sdcard. You can see what each B4A function returns in the following image: Page: 3
Issues With OS Reporting Wrong Screen Size On first run, the kindle fire reports the wrong screen size. Below (bottom left image) you can see the result and the reported screen size of a very simple B4A app. You can also see that the 20 pixel softmenu if visible and that the reported size is wrong. After rotating the device to landscape and back, you can now see that the device reports the correct screen size (bottom right image). You can even see that the MsgBox() is at a different location for it s center position because of the reported screen size. First Run After Device Rotated
You can also see in the images below, the issue is also in the landscape mode as well. The top image was the first run of the app. The bottom image is after the device was rotated to portrait mode and back to landscape. In both of these test the B4A app was set to full screen mode.
Issues With Carousel vs. App Panel The kindle fire has to ways to access your app. Through the Carousel(Main Screen) and through the Apps Panel. The Carousel is the main page that the kindle boots to, this is the home screen. It contains a short cut of the latest apps that have been used on the device. The Apps Panel is the normal panel seen in other Android devices when you select the apps tab or icon. The problem is, even though both access the exact same app, one shows issues when running a selected app and the other does not. Some apps show this issue when starting from the Carousel, while others show this issue when starting from the Apps Panel. I have found no pattern or cure for this at the current time. The image below is an example of this problem running the exact same app. When this issue shows up, it is a black bar that seems to always be on top and hides part of the screen. This shows up in some apps at the top, while in others it shows up at the bottom. It even shows up and causes a shift in the position of some B4A created panels. Reports have been sent to the Amazon Development Portal of this issue. See the example below: These seem to be the main issues when converting apps written for other devices to the kindle fire or when writing new apps. I started out with OS version 6.2.1. I thought these issues would be corrected in the next up. I now have the current OS updated to 6.2.2 (the current version) and these issues still exist. Other than these issues I have not found any others but I also have not used all features that B4A provides, so there may be others as we continue to work with this device. When converting our four apps, we have used VideoViews, WebViews, Panels, Timers, SQL Database, InputLists, etc. All these have worked with no issues other than those listed on the previous pages. One thing we did notice is that this device is fast! The look of the forked Android is the best we have seen as far as a 3D look. The buttons have more dimension and shadows, it s just a great looking OS but is has it s issues.
Amazon App Store Submissions App submission for the kindle fire is pretty straight forward. A few notes about some of the settings needed to submit your app and the changes we had to make when posting updates. Before we get into this, I also wanted to pass along what I was told by two different people working in the development portal of Amazon. I was told, Even if an app works and runs perfect on the kindle fire, does not mean it will make it to the kindle fire app store. It may make it to the Amazon app store, but not the dedicated kindle fire app store. This means, if your not on the kindle fire app store, the kindle fire device will not see your app and there will be no way to purchase or download it. If your app does make it on the kindle fire app store, it will also be placed in the Amazon app store, but not the other way around. They told me that the agreement we signed states this. That the kindle fire is their product and their branded device and they will pick and choose if an app is worthy to be placed on the kindle fire. B4A Settings for App Release In the screen below, you can see the syntax of the numbers required for the Amazon app store. Some stores we place our apps, ignores this panel altogether. These settings are required for the Amazon app store. The version string must be in the format x.x. It does not like formats of x.x.x, etc. This may change in the future but currently the format supported is x.x. Also, every update you submit you must increment the Version code integer number. You can not just change the Version string. Other than this, you simply fill in the requested data. As most of you, if not all of you, know that the package name /.apk file, must keep the same name and case usage. The Amazon app store is case sensitive and will reject the update or new version if the name, name case and the signing key is not the same. No special keys are needed other than the signing key used in B4A when you compile your app. The debug key will not work. We know this is not everything that may be found or that may be an issue on the kindle fire. If you find errors or can provide any new information please post the information and this PDF will be updated to contain this additional information. SEE SPECIFICATIONS OF THE DEVICE ON THE FOLLOWING PAGES.
Device Specifications Features Supported by the Kindle Fire Kindle Fire native support for audio
Asset Parameters