In the spring of 2017, this web site – appinventor.pevest.com – was moved to https://learn2c.org (or an alternate address https://appinventorplus.wordpress.com/)
The move was made for technical and practical reasons. Visit https://learn2c.org for updates made through out 2017 and into 2018.
However, things have changed since then and as of the spring of 2018, this web site may return to here. If that happens, the plan is for the new learn2c.org address to point here as well.
Many of the technical issues that caused to migrate a year ago have gone away or been solved.
The learn2c.org web site is hosted at WordPress.com and it appears Google down ranks WordPress web sites in search results. This old appinventor.pevest.com site – even without having been updated in a year, continues to receive many times more visits as a result of searches than does the WordPress.com hosted web site!
Finally, WordPress raised their hosting price last year.
Periodically, my Nexus 5 phone’s battery life is terrible. On good days, if I don’t use my phone, the battery discharge rate is slow – many hours later, the battery meter says there’s still over 90% of the battery charge remaining. But when it is bad, my unused phone can have its battery drain in 8 hours.
I have found two things to improve improve the battery life on my Google Android Nexus 5.
- One is to clear the system cache partition – this cache setting is not accessible from Settings.
- The other is to replace the Android launcher with Nova Launcher, available for free in the Google Play store.
How to Clear the System Cache Partition
To clear the system cache you need to enter a hidden Android start up menu, usually by starting your phone while pressing the power and volume control keys simultaneously. For specific instructions, see this explanation for the Nexus 5 (it might work on your phone too – this does work on my Nexus 5). Another list from a mobile phone service describes how to do this for other phones (I have not tested any of those).
Every few months, the battery life has gotten really bad. But after clearing the system cache partition, the phone returns to normal performance. I hope this works for you.
I noticed this might be related to my installing lots of apps on the phone, over and over again. Some days I’ll install my test app 10 or 20 or 30 or more times. After a few weeks of doing this every day, battery life problems develop. I clear the system cache partition and the phone is fine again.
You can learn more about the Android system partitions by reading this article.
As you may know, http is the old way to access a web site. https is the newer secure method that encrypts data sent to and from the web site.
Last year, Google announced it would rank search results such that web sites accessed via https rank higher than those using http.
This web page has been using http – which is okay since there is nothing secret or controversial about the content here.
However, on 7 March 2017, Firefox will launch an update that will issue a security warning when visiting web sites using http.
Consequently, we need to switch our web sites from http to https which involves paying a fee to buy an SSL security certificate and re-configuring software and servers.
I have successfully converted my coldstreams.com web site to https as a test for the conversion. So far everything looks good.
I will eventually convert the appinventor.pevest.com web site to use https also. I do not have a date for that – it could be next week or the end of the month. When I do the conversion, their might be a temporary period where you receive a security warning about accessing the web site, depending on how I do that update.
Just a quick update – I’ve been busy the past several weeks and did not get to complete the tutorials I had thought I would have done by now!
There are several topics I hope to cover soon including how you can store user interface components in App Inventor Lists. Say what?
Yes, you can create a list that contains, say, all the buttons you have on the screen. Why would you want to do that? Well you could use a simple for loop block to change the color of all the buttons simultaneously! And much more.
Another idea I’d like to implement is to modify my GPS app and have it send latitude and longitude coordinates to another phone using SMS messaging (instead of Firebase, as was done in that original version).
I’ve also done a little experimenting with creating Youtube video tutorials – but I have not posted any of these yet. I want them to have the right “feel” and quality before I put them online so I will continue to experiment with some ideas until I get them looking right.
Also, my apologies for not being on the Facebook group page very much. I’ll try to do better. Would you believe I did not even log in to Facebook for two weeks? My personal Facebook news feed (from friends!) has been overrun with angry and hostile political posts that turn off many people, including me. I just lost interest in logging into Facebook only to see a bunch of angry people expressing outrage every day.
I’ll try to better and get logged in this week and caught up. Lots of heavy rain the next few days so what else to do anyway?
Since 1 December, posts made here did not appear on Facebook or Twitter.
The software that transferred posts from this web site to social media stopped working and was no longer supported. The software developer had, in fact, given 9 months warning that the cross posting software would no longer be supported but I missed that announcement 🙂
I have installed and configured new software which appears to be working. The problem affected 4 web sites that I run so it took some time to find a good solution, test it out, and then roll it out to all of the other web sites too.
Now that this is done, I can get back to more interesting projects. I still have some Bluetooth related projects to finish and post here, plus I hope to post an interesting app that exchanges data between apps on different phones using text messages. I have not written that app yet but it looks straight forward – we hope!
Time to bring this blog into the modern era. The old style layout looked the same as most blogs of the past 5 or more years. The new layout is visually more interesting and appealing. I will be making a few more changes to this new layout, over the days to come.
See Part 0 for a brief introduction to this series and Bluetooth LE plus our past tutorial series on classic Bluetooth for communicating between Android devices, and between an Android device and an Arduino board with external Bluetooth transceiver.
Note – Bluetooth LE was introduced in the Bluetooth 4.0 specification. As of this writing, the latest version of the specification is 4.2. Bluetooth LE introduced capabilities to support very low power, battery operated devices that are designed to operate for weeks to months on a single battery or battery charge
Does Your Device Support Bluetooth LE?
To find out if your smart phone or tablet can work with Bluetooth LE: Go to the Google Play store and install the free app “BLE Checker” on your Android device. The app is simple – it tells you whether your device supports Bluetooth LE or not and that is all it does.
Devices that support Bluetooth LE will support BLE connections between compatible devices. However, this app does not tell you if your device supports a special BLE feature called “advertisements”. You can use Bluetooth LE without the “advertisements” feature but you will not be able to use all BLE features.
Continue reading Does your device support Bluetooth LE? Here is how to find out.
Wow! I just checked the web server data and the server estimate the http://appinventor.pevest.com web site is now read in 183 countries!
Using the United Nation’s count of 241 countries and territories, that means residents of 58 countries and territories have not visited yet!
But that means people in up to 183 countries are learning how to program Android apps using MIT App Inventor!