Archive

Archive for December, 2010

ack – Better than grep?

December 28, 2010 3 comments

I stumbled onto a really nice command line tool named ack while reading a StackOverflow question yesterday.  Living at the domain betterthangrep.com/, it purports to .. be better than grep.  Or, as they put it

ack is a tool like grep, designed for programmers with large trees of heterogeneous source code

I’ve written previously about how to combine find and grep, and really, ack exists to obviate the use of find and grep.  It ignores commonly ignored directories by default (e.g. all those .svn metadata folders that SVN insists on creating), and with a simple command line flag you can tell ack what sort of files you want searched.  Furthermore, because it recurses by default, you don’t need to use the find command to traverse the tree.

Using the todo example, a basic way of searching for the TODOs in all of our java files is to use the command

find . -name "*.java" -exec grep -i -n TODO {} \;

In ack, this is accomplished much easier:

ack -i --java TODO

Furthermore, the matching results are highlighted right away, making it extremely apparent where the matches occur.

I’m going to start using this at work and see if it can replace my grep/find hackery.  Will let you know.  Very impressed so far.

 

If you want to give it a try, the easiest way to install it is with macports:

port install p5-app-ack
Advertisements
Categories: unix Tags: , , , , , , ,

Give an indication of why a button is disabled

December 21, 2010 Leave a comment

In general, it’s a good idea to disable buttons whose functions cannot be accomplished at the given time.  For instance, if you have a table of data and a delete button that deletes the selected row or rows of data, it would make sense to disable the Delete button when no row is selected, and enable it when a row becomes selected.  This is superior to the alternative choice, which is to leave the button enabled and then indicate some sort of error message letting the user know that they can’t delete an empty selection, when they try to press it.

An example of an enabled and disabled button

If you do go down the route of programmatically disabling buttons, it is absolutely crucial that you give some indication as to why the button is disabled.  In the previous example, a savvy user could probably figure out that the delete action doesn’t make sense when there are no rows selected.  This isn’t always the case.
I dealt with an application recently where validation logic was spread across four different tabs, where each tab had a checkmark indicating that it was filled out correctly.  When I finally managed to get all of the tabs to show that they were in a valid state, the final button to complete the action stubbornly remained disabled.  I have no idea what the problem is, and there’s no indication whatsoever in the application.
The easiest thing the programmer could have done to give some feedback to the user is to provide a tooltip on the button that indicates why the button is disabled.  Perhaps a better solution would be to provide a small text pane in which the error messages would be displayed; this has the benefit of working with devices which do not have a mouseover tooltip capability (e.g. iPhone, iPad).
While it would have taken a little more effort on the part of the designer and programmer to make that screen more usable, it would have saved me the past two weeks of trying to solve the problem and waiting for their technical support.  Let that be a lesson for you.
Categories: UI Tags: , , , ,

0to255.com – find lighter/darker shades of colors

December 15, 2010 Leave a comment

Color choosers are a dime a dozen online, but 0to255.com is a very nice one.  Its stated purpose is to allow you to specify a color and then find shades that are darker and lighter than that color.  It’s very well designed, aesthetically pleasing, and has the good sense to allow you to copy the hex value of the color with a single click.

I use it on a semi-regular basis to design Java Swing UIs; just a quick tip for the Java folks out there – when you have the hex code copied, you need to preface the hex string with 0x for the Color constructor to work correctly.  In other words, if you are have the hex string #facade, you would create a Java color object with the command new Color(0xfacade).  The 0x tells the Java compiler to treat the following text as hexadecimal.

Categories: Java, UI Tags: , , , , ,

Two shortcuts for NetBeans navigation

December 10, 2010 Leave a comment

NetBeans is my Java IDE of choice, and I have written about it a few times in the past.  There are a slew of features to make you more productive and today I will highlight two shortcuts that are essential to efficient navigation.  I will show you how to jump quickly to any file in any open project, and how to search for a string in any file.

Jump to any file in any open project
⌃⇧ O

Ctrl Shift O = Go to File
By typing this shortcut at any time, you launch the Go to File dialog.  This dialog allows you type pieces of any file name, and you will see results returned in near real time.  This is excellent for when you know the approximate name of the file you’re looking for (you can insert a ‘*’ character as a wildcard, so if you know the word ‘foo’ appears somewhere in the word, you would search for *foo.

Search results are returned instantly

This dialog is a great example of incremental search, a UI technique I blogged about previously.  The incremental search is beneficial because it gives you instant feedback on your search query, allowing you to modify it as necessary to find what you’re looking for.
Those of you who use TextMate might recognize this feature; in TextMate this dialog is accessible via ⌘T (Command T).
The difference is that TextMate’s search is faster, and it is more forgiving (you can search for just a few letters in the file you’re searching for and still find it; you don’t need to know the precise name).
In general it’s much faster to search for files than to navigate through the file hierarchies manually.

Search for string

The second shortcut is to search for text in all the open projects (or narrowing it down to a select few files if you prefer).  This command is easily accessible when right clicking on a project node, but it’s accessible any time via keyboard shortcut as well

⇧ ⌘ F – Find in projects
Shift Command F

This one’s pretty self explanatory, but it took me awhile to stumble onto the shortcut, and it’s a pretty helpful one to know.

I hope these two shortcuts make your time in NetBeans a little easier.

Increase heap size for NetBeans Platform project

December 9, 2010 2 comments

To increase the heap size in a NetBeans Platform project, you can edit the nbproject/platform.properties file and add the line

 

run.args.extra=-J-Xmx1G

 

, replacing the 1G piece with however much memory you’d like. (The other solutions I found did not work for me). Thanks to the NetBeans Forums for this solution.

If you’re curious about the -J piece, it’s necessary to ensure that the arguments are passed to the JVM rather than interpreted by NetBeans itself. This should work in general for whatever arguments you want to pass to the JVM upon launch of your NetBeans Platform project.

Customize code formatting in NetBeans

December 6, 2010 4 comments
Sometime recently, (perhaps 6.9?) NetBeans changed the default code formatting algorithms.  I prefer to write my if/else statements as follows:

if (cond1) {
}
else {
}
I found that, every time I put else on a new line by itself, the else was automatically unindented, along with the closed bracket.

Indentation problems

After unsuccessfully searching online, I eventually stumbled onto some settings that control this behavior.  By default, NetBeans wants to format your if/else statements as follows:

if (cond1) {
} else { // 'else' is on the same line as the closing brace
}

If you want to have a new line after your closing brace, as I do, you need to change some settings.

Go into Preferences -> Editor -> Formatting.  Change the language to Java, and the Category to alignment.

New line settings panel

Make sure the “else” checkbox is checked in the “new lines” section.  Customize the rest of it to suit your coding style.

Categories: NetBeans Tags: , ,

Excel 2008 for Mac’s CSV export bug

December 6, 2010 7 comments
I ran into this at work a few weeks ago and thought I’d share.

Excel 2008’s CSV export feature is broken.  For instance, enter the following fake data into Excel:

Row Name Age
0 Nick 23
1 Bill 48
Save as -> CSV file

Full list of choices

When you use standard unix commands to view the output, the results are all garbled.

[Documents]$ cat Workbook1.csv
1,Bill,48[Documents]$
$ wc -l Workbook1.csv
0 Workbook1.csv
What is the issue?  The file command reveals the problem:
$ file Workbook1.csv
Workbook1.csv: ASCII text, with CR line terminators
CR stands for Carriage return, the ‘\r’ control sequence which, along with the newline character (‘\n’), is used to break up lines on Windows.  Unix OSes like Mac OS expect a single ‘\n’ new line character to terminate lines.
How can we fix this?

dos2unix.

# convert the Workbook1.csv file into a Unix appropriate file
dos2unix Workbook1.csv WithUnixLineEndings.csv
If you don’t have dos2unix on your Mac, and you don’t want to install it, you can fake it with the tr command:
tr '\15' '\n' < Workbook1.csv # remove the carriage returns, replace with a newline
Row,Name,Age
0,Nick,23
1,Bill,48
Very annoying that the Mac Excel doesn’t respect Unix line terminators.  Interestingly, I found a post that talks about ensuring that you choose a CSV file encoded for Mac, but that option seems missing from the Mac version itself.
If I’m missing something obvious, please correct me.