Install Android Studio on Ubuntu

Ubuntu

Android Studio is a great development environment and is available on Ubuntu. I’m using Ubuntu Mate 16.10 “Yakkety Yak”.
 
First install a Java Development Kit (JDK). OpenJDK is pre-installed or you can use Oracle Java 8 (there is a great guide here). I don’t wish to argue over your choice – I need to use the latter (my tutor does). Download Android Studio here. – I extracted it to /opt; ran the installer; and used my home folder for the SDK. If you are using 64 bit, you need the 32 bit GNU standard C++ library:
sudo apt install lib32stdc++6

For Arch you need to enable “multilib” repository:

<code><span class="pln">sudo pacman </span><span class="pun">-</span><span class="typ">Syu</span> <span class="pun">&amp;&amp;</span><span class="pln"> sudo pacman </span><span class="pun">-</span><span class="pln">S multilib</span><span class="pun">/</span><span class="pln">lib32</span><span class="pun">-</span><span class="pln">libstdc</span><span class="pun">++</span><span class="lit">5</span><span class="pln"> multilib</span><span class="pun">/</span><span class="pln">lib32</span><span class="pun">-</span><span class="pln">zlib</span></code>

Virtualisation support is interesting. I read two tutorial and Google’s guide. The former makes reference to command line options not in version 2.2.2. These posts suggest this is a bug, but it may now be default behaviour. First enable that virtualisation in BIOS (check if enabled using “kvm-ok”).

sudo apt-get install qemu-kvm libvirt-bin ubuntu-vm-builder bridge-utils
sudo adduser dougie kvm
sudo adduser dougie libvirtd

This results in an error.
screenshot-at-2016-11-25-21-16-19

Using the system version of libstdc++.so.6 works. Add the following to /etc/environment:

ANDROID_EMULATOR_USE_SYSTEM_LIBS=1

It seems snappy but with no feedback I’m unsure if accelerated.

So I now have a development environment set up for my project. The next hurdle is to choose a title. So far it is a: development project; distributed application; and uses Android.

Deauthorise old computers from iTunes

This took me a while to work out, on iTunes 12.2.1.16 (64-bit).

Open iTunes then from the menu iTunes Store→View Account. Once you’ve entered your password your details appear and you can click the “Deauthorise all” button.

Note you can only do this once a year – if you have done it already then the button just isn’t there.

Samsung RV511 backlight and Fedora 20

Put Fedora 20 on my Samsung RV511 yesterday, everything worked out of the box except the backlight. Using the keys or the slider moved the animation but didn’t change the brightness – which was set to nuclear eye ball toasting mode.

Both the slider and the key combinations change the values in /sys/class/samsung/backlight. I know that the ACPI BIOS can provide interfaces but not always methods to control brightness, so I added acpi_backlight=vendor to the GRUB_CMDLINE_LINUX entry in /etc/default/grub and the back-light is working fine.

Don’t forget to grub2-mkconfig -o /boot/grub2/grub.cfg.

Problems updating Nexus 7 (grouper) to Android 4.4.2

Latest update failed (4.3 to 4.4.2 I think) – just a forever spinning Nexus logo. Overwrote the tablet with a stock Nexus 7 (nakasi) image and all is well, besides needing to reconfigure everything and put my files back on it (thankfully Moon Reader Pro syncs positions with Dropbox/Google Drive).

You need the Android SDK installed (remember to add it to your path) and to have rooted the device – both covered in an earlier post. On the device hold down the power, volume up and down keys until the rescue screen appears.

Connect with USB and open a command prompt/terminal then type:

adb reboot bootloader

Download a stock image from Google – the Nexus 7 (nakasi) is this one. Decompress it and go to that folder in the command prompt/terminal, run either flash-all.bat (Windows) or flash-all.sh (Linux) and follow the prompts.

Word 2013 stopped saving

Wasted a good chunk of last night and today farting around with Microsoft Office 2013 after it decided to crash every time I saved. No idea what caused it, other than that it started after I had pasted some Python code from an editor.

Control Panel, Programs, Programs and Features. Select Microsoft Office 2013 and click Change. Quick repair didn’t work but full repair did.

Nexus 7 screen not coming on

My Google Nexus 7 had a weird fault earlier, its screen wouldn’t come on – just what you need before a nine hour flight. I tried a reset – it appeared to be caught in a loop with some static displayed on screen. I thought I might remove the back cover, disconnect the battery and take it from there.

Glad I did – the battery connector wasn’t engaged properly. A piece of insulating material had got in the way, preventing the connector locking in place. It must have worked loose.

Since then I’ve seen a few threads on Reddit with people mentioning that disconnecting and reconnecting the battery had fixed the same issue. I wonder if this is something more common than I thought?

Repair Samsung NC10 MBR

I removed Ubuntu from a Samsung NC10 yesterday, now the F4 recovery option doesn’t work. Please excuse the lack of screen shots on this Howto but I couldn’t think how to capture from the recovery manager and camera shots look rubbish.

It would appear that Samsung uses a custom Master Boot Record (MBR) – so for Grub all is well because you can choose to boot into the recovery partition and away you go. However if you have followed any of the usual guides to removing grub (such as running an XP CD to a recovery console and typing fixmbr) F4 will not launch the restore tool.

System Rescue CD is a great tool to have handy on a USB key. You can, so booting into it run this command:

fdisk /dev/sda

Now pressing “p” should show you that the recovery partition is 1, so type “a” then “2”, “a” then “1” to make it bootable. Now write the partition table by typing “w” then reboot. At this point you will boot into the recovery manager and be able to recover but the F4 key will not still not be available at boot and of course trying to create a backup will not work either (as Windows will be booted on restart).

Once Samsung Recovery Manager III has loaded up, press Ctrl+Alt+F10 – I had no idea there was a management mode until I read this page (French) but be aware its only available from the recovery partition. It asks for a password – “secos” (without the quotes). Once in management mode, click the “Image” tab and select “Export” then “Select Location”, I used “D:”. Click “Start” and accept the dialogue box that comes up. This is a backup of the recovery partition.

Once this stage is finished, select the “Tools” tab, insert a spare USB stick and click “Admin Tool USB”. It will format the USB stick and then install some utilities. It takes a couple of minutes. Once finished click the close button in the top right and it’ll ask if the computer should be turned off – say yes.

Boot with the USB key we just made, bringing you to a completely different recovery menu. Click “MBR Fix” and then close the application.

Now when you reboot you’ll notice that the MBR has been repaired and F4 once again boots into Recovery Manager III.

Compaq CQ10 failed BIOS update

A friend brought me a Compaq CQ10 over earlier. It seems it lost power during a Softpaq BIOS update. Initially the screen was booting to the HP BIOS recovery screen, attempting to rewrite and failing around 10%. I tried a few things and nothing worked, until the owner mentioned they’d upgraded the RAM.

Sure enough, it was a different size and type to the original specification so I refitted a 1 Gb 666MHz stick I had lying around from a previous upgrade and rebooted.

This time we re-flashed, verified and rebooted. Then it kept repeating this cycle so I took off the back panel (use the orange latch visible when the battery is removed) and removed the CMOS battery. After a short pause (30 seconds or so) I put it back and rebooted. This time there was an error message about the CMOS settings (unsurprisingly) and it rebooted.

However this time we got the Compaq BIOS boot screen, so I hit the escape key to enter BIOS. Then hit F9 to load default values, accept it and hit F10 to save values and hey presto the system is back up and running.

Bash

Two things that improve my bash productivity – stopping the cursor keys inserting characters in vim and history search in bash.

Edit ~/.vimrc or /etc/vim/vimrc (for system wide) and add turn off vi compatibility:

set nocompatible

The latter can be improved by editing ~/.inputrc (or /etc/inputrc for everyone). Pressing the up key scrolls through all the commands you’ve typed but by adding:

"e[A":history-search-backward
"e[B":history-search-forward

You can type the first letter or two and get the command you need, so if you typed “mysql -u root -p” last Tuesday but can’t remember the options, typing “my” and pressing the up key will find it.

Watch TV with VLC and a Freecom DVB-T Stick

One of the things I need my Aspire One to do is watch TV.  When you’re away, it’s nice to be able to watch a little TV.  I bought a Freecom DVB-T USB stick years ago and have always had success under Linux.  It’s small, sensitive and selective.

I was surprised, especially on Ubuntu, how easy it was to setup.

My netbook runs Arch, so I installed it on that and my Dell 1545 running Ubuntu 9.04.
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