25 Sep 2009
selecting just an image in hover as an attribute
in the blogs i have pictures as links to big versions of the picture and i have text links. The text links i want to highlight when you hover over them, but the pictures not.
After a bit of fiddling around, this is what eems to work...
in the css file
/* create a special class for images so they don't get annoying colour blocks when hovered over */
#blog_content a.imagehc:hover {color: white; background: white; }
<a href="images/first block detection screen.JPG" class="imagehc"<img src="images/first block detection screenSML.jpeg" alt="some placeholder words for the tool tip" />
11 Aug 2009
Tims aide memoire for CSS.....
Every time I return to CSS I seem to struggle to get the syntax in my head so I thought I'd make a little example page of the major construction types.
The output of the following HTML/CSS examples/both HTML and CSS are validated as ok by the validator
Here is the HTML File...
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE html PUBLIC
"-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" xml:lang="en" lang="en">
<head>
<title>Tim's Example Page of CSS declarations</title>
<link type="text/css" rel="stylesheet" href="examples.css" />
</head>
<body>
<h5>Tim's example page</h5>
<p>Hello World</p>
<h1>I am heading 1</h1>
<h2>I am heading 2</h2>
<table>
<tr><th>column1</th><th>column2</th></tr>
<tr><td>no para</td><td><p>para</p></td></tr>
</table>
<h3>I am heading 3</h3>
<h4>I am heading 4</h4>
<p id="onlyoneid">There is only one use of this selector</p>
<p class="multipleuses">There can be lots of use of classes</p>
<h1 class="multipleuses">like this</h1>
</body>
</html>
/* define all text as black */
body { color: black; }
/* define all the <p> tag entries as red */
p { color: red; }
/* define all h1 and h2 tag entries as green */
h1, h2 {color: green; }
/* define all paragraphs in table data elements as blue [a contextual selector]*/
td p {color: blue; }
/* define all h3 and h4 entries as grey and italic [known as grouping selectors]*/
h3, h4 {color: gray; font-style: italic;}
/* define h4 as bold too - show that multiple css statements can refer to one tag type*/
h4 { text-decoration: underline; }
/* define id selector onlyoneid - ids only used once so that javascript and others can locate the exact point in the page */
#onlyoneid { color: yellow; }
/* define class multipleuses which can be used wherever you like */
.multipleuses { text-decoration: underline; }
10 Apr 2009
Silly characters showing on web page.
If you are using a standard UTF 8 font then when writing it is important to avoid smart quotes.
A useful tip if you are using textwrangler is to show invisibles.
4 Mar 2009
(Link for this specific entry...)
2 Nov 2008
The good and bad of the internet
One of the big things that has changed since I last programmed is the Internet.
The ability to log on and find some discussion or code fragments that do what you are trying to do,
or to answer the questions you are trying to answer is fantastic.
At the moment I am trying to get the blog writing app to write out resized images - I don't want to
draw them on screen only load them and save them again.
Now this requires me to use the class NSImage - one that is not in the foundation set of classes, but
in the appkit - now as I am building a command line utility when I used NSImage it failed with a
linker failure - something I have not seen before in Xcode.
So after several hours of struggling I posted a question on Mac Forums and when I got up this morning there
was a response that gave me the clue I was looking for ...
macforums
wonderful.
On the other hand there is a real danger that you start picking up code from other people and you don't really deeply know what you are doing -
Here for example I found someone who had the problems I had this morning - failing to resize an NSImage and then getting crashes
Great the answer is good and works for me -
cocoabuilder
But I don't really (deeply) know what he is doing. Sure at some superficial level it is clear he is drawing the old bitmap onto a new bitmap of the
right size but I have not put those lines of code together and read the manual on each of them so I am in danger of kidding myself
I know what I am doing!
Anyway here is my finished code for a command line utility to resize a jpeg image file.
blah
1 Nov 2008
Resizing a jpeg in Cocoa
If your image has an NSBitmapImageRep it's dead simple. Get the image
rep and send it
- (NSData *)representationUsingType:(NSBitmapImageFileType)
storageType properties:(NSDictionary *)properties.
NSBitmapImageRep* bm = [NSBitmapImageRep imageRepWithData:[image
TIFFRepresentation]];
NSData *sourceData ... // Get your data from a file, URL, etc.
float resizeWidth = 13.0;
float resizeHeight = 13.0;
NSImage *sourceImage = [[NSImage alloc] initWithData: sourceData];
NSImage *resizedImage = [[NSImage alloc] initWithSize: NSMakeSize(resizeWidth, resizeHeight)];
NSSize originalSize = [sourceImage size];
[resizedImage lockFocus];
[sourceImage drawInRect: NSMakeRect(0, 0, resizeWidth, resizeHeight) fromRect: NSMakeRect(0, 0, originalSize.width, originalSize.height) operation: NSCompositeSourceOver fraction: 1.0];
[resizedImage unlockFocus];
NSData *resizedData = [resizedImage TIFFRepresentation];
[sourceImage release];
[resizedImage release];
22 Oct 2008
More Apache Hassles
I want to include the vertical menus on my webside by server side includes -
using the <!-- #include --> directive - this however took me a little while to cope with.
Firstly there are two forms -
<!--#include file="somefile.html" -->
<!--#include virtual="someotherfile.html"-->
/Users/someuser/Sites
#
# DocumentRoot: The directory out of which you will serve your
# documents. By default, all requests are taken from this directory, but
# symbolic links and aliases may be used to point to other locations.
#
DocumentRoot "/Library/WebServer/Documents"
and replace with the path to your sites folder, mine is "/Users/someuser/Sites"
#
# This should be changed to whatever you set DocumentRoot to.
#
<Directory "/Library/WebServer/Documents">
And change there as well, e.g.
<Directory "/Users/someuser/Sites">
11 Oct 2008
TRUE and FALSE, YES and NO
I have always had trouble remembering which way the boolean values map in C (1 = TRUE, 0 = FALSE )
Although TRUE and FALSE are not actually defined unless you do a type_def
Of course it is worth remembering that C treat evaluation of any non-zero result as true.
So if ( 100 ) do something; // will mean always do it. and...
if (! 100) do something; // will mean never do it.
So ok fair enough, but then in objective C we do have a BOOL type with YES and NO as values
but how exactly do the two interrelate and can you assume YES is the same as TRUE?
Another few hours struggling to find an issue with displaying CSS on Apache2
The blog pages currently use two cascading style sheets - and some of the styles were rendering
properly and others not. PearsonMain.css was not rendering but OMWB.css was rendering. After hours of
trying to find in something that was wrong with the PearsonMain.css file I had a look int he Apache2 log file
In Mac OS 10.5 (at least for me) this meant going into terminal using the cd command to get to var/log/apache2
and then using the tail command - tail access_log to see the apache access log.
I got the following.....
192.168.1.69 - - [11/Oct/2008:18:22:48 +0100] "GET /~tim/Car/Car-OMWB.shtml HTTP/1.1" 200 1191
192.168.1.69 - - [11/Oct/2008:18:22:48 +0100] "GET /~tim/images/achnag_from_the_air.jpg HTTP/1.1" 200 6527
192.168.1.69 - - [11/Oct/2008:18:22:48 +0100] "GET /~tim/OMWB.css HTTP/1.1" 200 398
192.168.1.69 - - [11/Oct/2008:18:22:48 +0100] "GET /~tim/PearsonMain.css HTTP/1.1" 403 222
192.168.1.69 - - [11/Oct/2008:18:22:48 +0100] "GET /favicon.ico HTTP/1.1" 404 209
Tims-iMac:Sites tim$ chmod a+rwx PearsonMain.css
Tims-iMac:Sites tim$ ls -l
total 136
drwxr-xr-x 11 tim staff 374 11 Oct 18:15 Car
drwxr-xr-x 8 tim staff 272 11 Oct 10:48 Computing
-rw-r--r--@ 1 tim staff 398 11 Oct 18:08 OMWB.css
-rwxr-----@ 1 tim staff 1837 11 Oct 13:11 PearsonMain copy.css
-rwxrwxrwx@ 1 tim staff 1440 11 Oct 18:05 PearsonMain.css
-rw-r--r--@ 1 tim staff 1440 11 Oct 18:09 PearsonMain2.css
-rwxrwxrwx@ 1 tim staff 1466 5 Sep 18:59 family.css
-rwxrwxrwx 1 tim staff 1118 27 Apr 12:46 family_handheld.css
drwxrwxrwx 20 tim staff 680 8 Oct 10:08 images
-rwxrwxrwx@ 1 tim staff 2104 10 Oct 19:35 index.shtml
Tims-iMac:Sites tim$ <br />Tims-iMac:apache2 tim$ tail access_log
192.168.1.69 - - [11/Oct/2008:18:52:54 +0100] "GET /~tim/Car/Car-OMWB.shtml HTTP/1.1" 200 1191
192.168.1.69 - - [11/Oct/2008:18:52:54 +0100] "GET /~tim/OMWB.css HTTP/1.1" 200 398
192.168.1.69 - - [11/Oct/2008:18:52:54 +0100] "GET /~tim/images/achnag_from_the_air.jpg HTTP/1.1" 200 6527
192.168.1.69 - - [11/Oct/2008:18:52:54 +0100] "GET /~tim/PearsonMain.css HTTP/1.1" 200 1440
192.168.1.69 - - [11/Oct/2008:18:52:54 +0100] "GET /favicon.ico HTTP/1.1" 404 209
192.168.1.69 - - [11/Oct/2008:18:52:54 +0100] "GET /~tim/images/header_fill_pic.jpg HTTP/1.1" 200 990
192.168.1.69 - - [11/Oct/2008:18:52:54 +0100] "GET /~tim/images/PFW_Title_Bar.jpg HTTP/1.1" 200 9843
Tims-iMac:apache2 tim$ <br />Tims-iMac:Sites tim$ chmod o+r PearsonMain.css
10 Oct 2008
How to change the organization name in the objective C development environment
From Terminal
defaults write com.apple.xcode PBXCustomTemplateMacroDefinitions'{ ORGANIZATIONNAME = "Tim Pearson"; }'
9 Oct 2008
Relatively little done today, I have tidied up some of the code, and I have made some alterations
to allow the output to be put in the right locations - so that it links to the main site home page.
This generated me a new problem, in that it was the first time I had run the blog output under apache.
(as opposed to just opening the file from the computer - see yesterday's post if this doesn't make sense)
Running under apache2 browsing from safari gave me a problem that only one of the two style sheets
loaded by the header to each page - seemed to be having any effect - so the pages are rendering
poorly.
You can see the difference looking at the same test pages below - they are exaclty the same bit of
html/css, not even copies the same files in the same place - it's just one is being served by apache
and one is being opened directly from the file system.
Here is it loaded with Apache -
And here it is loaded as a straight file form the browser -
argh
Other things to do -
1/ Multiple Blogs - the code is really designed only to do one blog at a time at the moment, as I eventually
want it to do all the blogs then I think I should fix this soon.
2/ jpgs/pngs/gifs etc. - it doesn't move them around or put the links in for them at all yet
3/ filling up the navigation bar
4/ testing it on an online system