The Wiert Corner – irregular stream of stuff

Jeroen W. Pluimers on .NET, C#, Delphi, databases, and personal interests

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Archive for May, 2012

Searchable UTF8 Unicode Characters

Posted by jpluimers on 2012/05/31

Brilliant: site where you can Search UTF8 Unicode Characters.

If you know part of the name of a Unicode character, you can now try and find it, then copy/paste it from that site.

Edit: 20160403: that site disappeared, but this one works: Unicode Character Search and Shapecatcher.com: Unicode Character Recognition still works.

–jeroen

Posted in Development, Encoding, Power User, Software Development, Unicode, UTF-8, UTF8 | Leave a Comment »

Pointers to value and to reference types (was: delphi – Why does TValue.Make require a pointer to an object reference? – Stack Overflow)

Posted by jpluimers on 2012/05/30

Delphi seemingly makes the distinction between reference and value types disappear, especially because it hides the ^derefererncing operator for most usages:

  • there is no ^ dereferencing operator when following “class” type object instances, “interface” references and “object” type object instances, strings, open arrays and dynamic arrays: the dereferencing is implicit
  • usually you do not need the ^ dereferencing operator when

Rudy Velthuis wrote a great article on pointers in general. Though it was in the Delphi 2009 timeframe, almost everything is very valid. A few things are missing, some additions are below.

I’m not going into deep detail here right now, just a few notes to get people interested going.

Hopefully I will some time in the future to either go into more detail, or point to articles that do.

  1. “object” style object instances.
    Those have been deprecated since Delphi 1 (which introduced “class” style objects), but there are still libraries that use them, and (almost unbeleivable): they are supported in Delphi x64
  2. anonymous method references
  3. Events (method references) aka the “procedure … of object”/”function … of object”
    are implemented using the underlying TMethod type from the System unit
    always use the “Assigned” method to check if both the Data and Method field are non-nil

Even with those additions to Rudy’s list, I’m not 100% sure everything is complete now (:

–jeroen

via: delphi – Why does TValue.Make require a pointer to an object reference? – Stack Overflow.

Posted in Delphi, Development, Software Development | 4 Comments »

What you need on your Mac to develop for OS X or iOS using Delphi XE2

Posted by jpluimers on 2012/05/29

Just a few notes on things I told Delphi cross development students over the last nine months or so.

For Mac OS X apps:

  • The Platform Assistant Server that ships with Delphi XE2

For iOS apps:

Steps:

  1. Become a registered Apple Developer
  2. Download and install xCode 4 when you run on OS X 10.7 Lion or higher, or
    Download and install xCode 3 when you run on OS X 10.6 Leopard
  3. Download and install FreePascal 2.4.4
xCode includes the iOS SDK
Delphi uses the Delphi compatibility mode of FreePascal.

–jeroen

via: Developer Tools Overview – Apple Developer.

Posted in Delphi, Delphi XE2, Development, Software Development, xCode/Mac/iPad/iPhone/iOS/cocoa | 1 Comment »

Interesting: Electric Imp with Arduino (via: electric imp – developer kits)

Posted by jpluimers on 2012/05/28

Electric Imp – that wants to power The Internet of Things using imps – is introducing some really interesting hardware, one of the devevelopment kits combining Arduino and Imp on one board:

Duino: Arduino, with Imp

Featuring an ATMEGA328 processor, this board is compatible with the Arduino Uno but instead of having a USB-serial port on it, it has an Imp socket. You can use a modified version of the Arduino IDE to update the ATMEGA code from anywhere in the world when an Imp is plugged in, and use simple serial commands in your Arduino programs to control other Imp devices.

The ATMEGA will operate standalone when no imp card is inserted.

Dimensions: 72mm x 54mm x 14mm

Power supply: USB Mini-B socket (5v) or 2.1mm barrel jack (7-12v)

Price: $20

Some must read links:

–jeroen

via: electric imp – developer kits.

Posted in Arduino, Hardware Development, Hardware Interfacing, USB | 2 Comments »

How much USB power does a device use or provide? Apple Computers and Displays: Powering peripherals through USB

Posted by jpluimers on 2012/05/28

Two quotes:

Apple peripheral devices may request more than 500 mA (Milliamps) at 5 V (Volts) from a port to function or to allow for faster charging. Such Apple peripheral devices include:

  • Apple MacBook Air SuperDrive (when connected to supported computers)
  • Aluminum Wired Keyboard*
  • iPod
  • iPhone
  • iPad

Open System Profiler to find more information about peripheral power requirements, or contact the manufacturer of your peripheral. For the most accurate information about power usage, make sure your device is connected directly to your Apple computer or display before opening System Profiler.

All this because of the iPad charging challenge.

–jeroen

via: Apple Computers and Displays: Powering peripherals through USB.

Posted in Apple, Gadget, Power User | Leave a Comment »