SmartTextField demo

SMARTTEXTFIELD 1.2 DEMONSTRATION

[ Java links | SmartTextField notes | Sample code ]

Try clicking in the text fields in each of the applets on this page and then tabbing (pressing the Tab key) and shift-tabbing (same thing, but with the Shift key held down too).

See the difference?

ColorTest using the standard java.awt.TextField class:
(If Java were enabled, you would see a demo color picker here using Java's standard TextField.)

`ColorTest` using the standard `java.awt.TextField` class:
(If Java were enabled, you would see a demo color picker here using Java's standard TextField.)

ColorTest using the SmartTextField class:
(If Java were enabled, you would see a demo color picker here using my enhanced TextField.)

`ColorTest` using the `SmartTextField` class:
(If Java were enabled, you would see a demo color picker here using my enhanced TextField.)

Feedback, please!
After weeks of effort, I have concluded that the various implementations on various platforms of Java's Abstract Windowing Toolkit are ALL so buggy, and so idiosyncratically buggy, that there is no point in trying to provide further workarounds. Sooner or later, Sun, Netscape and Microsoft will fix these bugs, and then we won't have this bother. It's been a productive learning experience though. I reckon I now know Java through and through. The language clearly has enormous potential, and I like it too. A really cool language, well thought out and well designed.
Currently, this applet behaves completely correctly under 3 out of 4 runtimes tried on the Macintosh. It behaves partially correctly under MS Internet Explorer on the Macintosh and under all runtimes tried so far on Windows 95 and SGI IRIX.
As far as I can tell, my code's methods all run correctly if and when a runtime actually calls them. I currently believe that each problematic runtime's failure to call one or more methods at the appropriate time is that runtime's implementer's bug, not mine. My source code is available for critical evaluation, and I would appreciate any feedback.
Netscape Navigator 3.x for Win32, and MS Internet Explorer 3.x for both Mac and Win32, all demonstrate at least some of the features correctly and do not crash, but also miss out some functions ~~ eg MSIE for Win32 doesn't change the rectangle's color, NN for Win32 lets you shift-tab out of all fields correctly but only lets you tab out of some fields, and MSIE for Mac responds to all tab-key presses in applets by selecting the address bar. There it rests for now.

(Based on the


		ColorTest

applet from Teach Yourself Java for Macintosh in 21 Days by Laura Lemay and Charles L. Perkins with Timothy Webster, Hayden Books 1996, so portions © them).

Technical
details:

Each Applet consists of a Canvas (for showing the color) and two Containers, all laid out left to right.
Each of the two Containers in each Applet contains three Labels and three TextFields / SmartTextFields, laid out vertically in columns.
The SmartTextFields are actually specialised descendants of NumberTextField, an abstract subclass of SmartTextField providing public methods to treat a SmartTextField as if it was a Number. The concrete classes used here restrict input to numeric characters and values within specific ranges. They are:
- UByteTextField, for numbers in the range 0 - 255 (the possible values of an unsigned 8-bit byte)
- DegreeTextField, for numbers in the range 0 - 360.
- PercentTextField, for numbers in the range 0 - 100.

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