Insert a Link into a Google Spreadsheet in Google Docs

In the Google document editor, it's super easy to insert a link. Just hit the 'link' button, type the URL and link text and your done. Or even better, type the link text direct into your document, select it and press CMD-K (CTRL-K on a PC).

In Google spreadsheets, there's no such button. Happily it is still possible, though rather more fiddly.

Select a cell and type:

=HYPERLINK("http://www.example.com/link"; "Link Text")

The link will appear, and it will behave exactly the same as links in Google Docs. I'm looking forward to Google adding a button to make this easier.

Android: Fading between two Activities

Here's the code to do a nice smooth fade between two Activities..

Create a file called fadein.xml in res/anim

<?xml version="1.0" encoding="utf-8"?>
<alpha xmlns:android="http://schemas.android.com/apk/res/android"
   android:interpolator="@android:anim/accelerate_interpolator"
   android:fromAlpha="0.0" android:toAlpha="1.0" android:duration="2000" />

Create a file called fadeout.xml in res/anim

<?xml version="1.0" encoding="utf-8"?>
<alpha xmlns:android="http://schemas.android.com/apk/res/android"
   android:interpolator="@android:anim/accelerate_interpolator"
   android:fromAlpha="1.0" android:toAlpha="0.0" android:duration="2000" />

If you want to fade from Activity A to Activity B, put the following in the onCreate method for Activity B before setContentView.

overridePendingTransition(R.anim.fadein, R.anim.fadeout);

If the fades are too slow for you, change android:duration in the xml files above to something smaller

iPhone-Style Buttons for Android

I recently started work on apps for android and quickly tired of the default buttons that Android provide - especially the nasty default flashes of green and orange when the button is tapped. Eurgh.

Happily, the Android SDK provides a neat way to build custom buttons, and to use them throughout your application. Here I present some vaguely iPhone-style gradient-filled buttons I created using this method.

Background Images

First up you need to create the button background images themselves. You need separate images for at least the normal and selected states, and optionally the 'highlighted' state too. Highlighted is when the user selects the button using the (in my opinion entirely pointless) trackpad. Here I've been a bit lazy and used the selected state for highlighted rather than making a whole new image.

You need to make versions of the image for hi-res devices like the Nexus One or HTC Desire (hdpi), and medium res versions for other devices like the HTC Legend (mdpi). So far I've used the same images for medium res and low res, and it seems fine.

Here are the images I created (right-click to download).

Hi-res png. Normal and Tapped

Medium res png. Normal and tapped

Making the images stretchable using draw9patch

Next you need to tell Android how these images can be stretched to make buttons of different sizes.

Run the draw9patch.jar application (in your android sdk's tools/lib folder).

The official instructions for the draw9patch tool are rather vague, so here's what I did.

• Drag-and-drop one of the button images onto the tool.
• The image will appear in the left panel.
• Choose an edge. I start with the top.
• Decide on which part of the image should contain the button content. For a button like this one you'd choose the largest possible straight bit of the edge you're currently working on.
• The image is displayed with an extra one-pixel gap around the edge. You're going to be drawing in the one-pixel gap to mark up the edges.
• Click and drag the mouse over the one-pixel gap to draw in black pixels to mark the largest possible straight part - make sure you don't miss any pixels.
• In the image above I've coloured in roughly the middle third of the top edge. If you make a mistake, hold shift and click to erase pixels.
• Repeat with the other edges.
• If all has gone well, you'll see a preview on the right of what the button looks like stretched.
• Repeat for each edge.
• Save the file. When you give it a name, don't provide the extension. The file will be saved as a 'name.9.png' file.
• Repeat for each image.
• My filenames were button_black.9.png and button_black_tap.9.png. Make sure you give the medium and high res images the equivalent names. This is important later!

Copy the .9.png files to your project

Copy the high-res .9.png images into your res/drawable-hdpi folder (make it if it doesn't exist), and the medium-res into res/drawable-mdpi AND res/drawable-ldpi. If you omit the ldpi image Android appears to use the high-res image on low-res devices.

Create the drawable to define normal, tapped, and highlighted states

Now we can create our custom button style. We're going to define a 'drawable' called black_button that will use the black_button and black_button_tap images we made above.

Put this in an xml file called 'black_button.xml' inside the res/drawable folder.

<?xml version="1.0" encoding="utf-8"?>
<selector android="http://schemas.android.com/apk/res/android">
<item state_focused="true" state_pressed="false" drawable="@drawable/button_black_tap">
<item state_focused="true" state_pressed="true" drawable="@drawable/button_black_tap">
<item state_focused="false" state_pressed="true" drawable="@drawable/button_black_tap">
<item drawable="@drawable/button_black">
</item></item></item></item></selector>

This document tells android to use the tap image for the focused and pressed states when you use the drawable called 'black_button'.

Create the style

Next we need to define a style which we can use for the button. Android styles are a powerful way to collect together images, font, and layout settings that are common to widgets in your app. Making a style now will make it super-simple to make 'black_button' styled buttons later on.

Place this in the res/values folder in a file called styles.xml (or add the 'style' part to your existing styles if you have them). Note that we've set the background property to point to the drawable 'button_black' we just defined.

<?xml version="1.0" encoding="utf-8"?>
<resources>
<style name="button_black">
<item name="android:background">@drawable/black_button</item>
<item name="android:textColor">#FFFFFF</item>
<item name="android:typeface">sans</item>
<item name="android:textStyle">bold</item>
<item name="android:textSize">20sp</item>
<item name="android:gravity">center</item>
<item name="android:layout_margin">3sp</item>
</style>
</resources>

Using the style on your buttons

Now we are ready to apply this style to buttons in our app. All you need to do is to set the 'style' attribute on the Button definition in your layout.xml files to point to the style we just defined.

Here's an example.

<Button android:text="Add from URL" android:id="@+id/addButton"
android:layout_height="wrap_content" android:layout_width="fill_parent"
android:drawableLeft="@drawable/menu_add"
style="@style/button_black"
></Button>

How to hide .svn folders from file search in Eclipse

By default, whenever you do a file search in Eclipse, it'll search inside .svn folders too. This is obviously very irrititating!

Here's how to turn it off:

• Click on the root of your project in the Package Explorer window
• On the main manu, select Project / Properties / resource / Resource Filters
• Click Add..
• Set 'Filter Type' to 'Exclude all'
• Set 'Applies to' to 'Folders'
• Check 'All Children (recursive)' (this is essential!)
• Under File and Folder Attributes, type .svn. This should work for CVS folders too (type .cvs)
• Click OK
• Repeat for all projects in your workspace

Apparently installing subclipse (subversion plugin for eclipse) will also solve this problem but I haven't tried it myself.

Android: Adding a new Activity using Eclipse

To add a new screen to your android app you'll want to add a new activity. This is a slightly manual process however, so I've noted down here for future reference.

This example will add a new activity called 'Foo'.

Step 1 - Add the activity class

• In the Package Explorer, right click your main package (e.g. com.calvium.myApp) and select New / Class
• Set the new class Name (e.g. Foo.java), and set it the superclass to android.app.Activity
• Add an override for the onCreate method.
• Easy method: Open the new file and place your cursor inside the main { } block. Press CTRL-SPACE and up pops a list of possibilities. Type 'onCreate' and hit enter to generate the method stub.
• After super.onCreate add:

setContentView(R.layout.foo);

Step 2 - Create the Activity Layout File

• Back in the package explorer, right-click res / layout.
• Select New / Other / Android / Android XML File
• Call the new file foo.xml
• Add whatever controls you want to the xml file using the designer tool in eclipse, or by typing stuff manually.

Step 3 - Register the new activity in the AndroidManifest.xml file

• Open AndroidManifest.xml
• Just before the closing tag insert:

<activity android:name=".Foo">activity>

Installing an archived application to an iPhone from XCode Organizer

The organizer window in Xcode has a handy feature where all the versions of applications you have submitted to the App Store are listed.

Today I needed to install an old version of an app to my iPhone in order to reproduce an issue a customer was having. It wasn’t as easy as I was expecting so I thought it was worth recording the process. Essentially you cannot simply copy the archived app to your device manually, as it was signed using the App Store certificate. We need to re-sign it using an Ad Hoc certificate instead - then it’ll run.

First up you need to make sure that you have an Ad Hoc distribution certificate handy, and that said certificate includes the device that you’re trying to distribute to.

UPDATE: August 2012: This process is far easier if you use this free open-source app called iResign.  This great app lets you take an existing IPA and re-sign it with your own certificate. Much, much simpler

Making the Ad Hoc Certificate

Ignore this part if you already have an Ad Hoc distribution certificate.

1. Get your team agent to log into the iOS provisioning portal
2. Go to provisioning / distribution tab
3. Hit New Profile

1. Choose ‘Ad Hoc’ as the distribution method
2. Choose the relevant app ID (I chose an app id that allows any application by Calvium)
3. Select the devices you want to be able to run on. I just chose all by selecting the select all button.
4. Hit ok. Wait a minute or so, and hit refresh to be sure that the certificate is ready.

Re-signing the app using the Ad Hoc Certificate

1. Go back to Xcode organizer. Open the ‘archived application’ section and choose the app you want to use.
2. On the right-hand panel, choose the version to use. I’ve chosen 1.2. Apologies for the censorship in the images here..

3. Click Share

1. Click the ‘identity’ drop-down and under the heading ‘Ad Hoc Distribution’, select ‘iPhone Distribution’
2. Now click ‘Save to Disk’
3. Choose a filename (doesn’t matter what it is)
4. Xcode will grind away for a bit re-signing the app, and then save a .ipa file containing the app.

Installing the app on your device (the .ipa file)

There are various ways of installing the ipa on the device, including via iTunes. I find this method by far the easiest - no syncing required.

1. Open Xcode organizer again
2. Attach the device
3. Open the ‘Devices’ section, and select the device

1. Under the Applications box, click the + arrow.
2. Select the .ipa file you just saved, and lo and behold the app will be installed
3. If it fails with an ‘no provisioning profile found’ or ‘invalid entitlements’ or similar, check that the ‘Provisioning’ box above contains the Ad Hoc profile you created earlier. If not, download it from the iOS provisioning portal, and manually upload it by clicking the + button under provisioning.

Screen sharing on Mac OS X Server using VNC

Chicken of the VNC is a free open-source Mac application that allows you to view a remote desktop on another networked machine.

Here's how I set it up on my Mac running 10.6, and our Mac Server (10.6 too).

• Run Server Admin on your local machine
• Open up the server you want to connect to
• Select Firewall.
• Go to Settings / Services tab
• If 'Allow traffic only to these ports' is selected we need to add the ports that VNC will use.
• Click the little + button at the bottom-left of the list of services
• Add a new service called VNC 1, using port 5800, TCP + UDP
• Add a second service, VNC 2, using port 5900, TCP + UDP
• Stop and restart the firewall

• Download Chicken of the VNC and install it.
• Run the app
• Go to Connection / New Connection
• Enter the IP address or name of your server
• Leave 'display' as 0 (if you choose 1 you'd have needed to open ports 5801/5901 above for example)
• Leave 'profile' as 'default profile'
• Check the 'save server' box.
• Hit connect.

If all goes well you should have a window pop up displaying the screen of the server.