Smart Layouts

Disclaimer

Please do not email me about this project without reading the disclaimer above.

There has been a tiny bit of progress. Back in 1979 I invented the scaffold for the text mode screen and introduced it in the Abundance computer language. Abundance has keywords for aligning automatically scrolling fields in rows or columns (or any other shape), automatically labeled. The language never caught on. There have been various report generators. A common problem with them is that the reports look klunky and use huge amounts of screen or paper real estate unless you hand tune the reports. In the late 1990s, Java introduced the Layout for the GUI (Graphic User Interface). It allows fields to automatically grow and shrink depending on how much screen real estate is available. In this project I would like to combine some of the features of Abundance smart objects and scaffolds with features from Java Layouts to create smart Layouts for Java.

The idea is this. Instead of carefully specifying how to lay out a dialog box, the programmer just specifies which fields are to be included. The smart layout completely handles laying out, labeling and displaying the fields. Its job is to produce beautiful layouts given the constraint of how much screen real estate is available.

How could this possibly work? First you need smart objects. They must be able to tell the layout manager such facts as:

• Size

  : What is the minimal size of field that would still be useful to view without scrolling?

• Justification

  : Should such data be left or right justified. In other words, should fields line up with others on the left or right end? Numeric fields typically align on the right. Fixed length fields can align either way and still look aesthetically correct.

• Label

  : Fields should be able to tell you their names in various languages so that if there is room, the fields can be labeled, or so that labels can be displayed with hover help. It is the layout manager’s problem to figure out where to place the labels, not the object’s.

• Priority

  : How important is this information? Does it always have to be visible, or is it ok to display it only on request?

• Relationships

  : What is the hierarchical relationship of the fields and their natural order? Which fields are most closely to related to which other fields?

• Lore

  : Special layout requirements, e. g. An address has components, Name, Street, City, Province/State, Country, PostalCode, phone numbers, URL (Uniform Resource Locator), email ids. Every country has a different rules for how addresses should be precisely laid out. Some countries even have a two part postal code. Smart Layouts need to know this lore so they can deal with any mixture of address on the planet without specific application code.

What sort of tricks can you use if real estate is very tight?

1. Shrink/expand each field box to fit the current data rather than trying to use a uniform layout optimised for average or worst case data.
2. Use a smaller font.
3. Use a condensed font.
4. Set up ScrollPanes.
5. Hide low priority information, replacing with an icon you click to see the details.
6. Use a times square display.
7. Suppress labeling fields.

Even if your smart Layout does not generate layouts as beautiful as could be hand crafted, it will generate them accurately and quickly, at a fraction of the cost of having humans meticulously lay them out and tweak them with GridBags. It becomes possible to write applications that generate new reports and layouts dynamically, trusting your layout manager to come up with something reasonable. Internationalisation becomes much cheaper since layouts don’t have to be hand-tweaked for each language.

An initial version may run prior to compilation and generate Java code. It does not matter if it is slow to execute. As computers get faster it may become feasible to write a version that runs as a standard layout manager. Eventually you could conceivably run it every time any value in a display changes.

I have already done some work with smart, self-labeling Java objects. My objects are primarily concerned with data entry, automatically generating data entry prompts and error messages and fetching and storing data from JDBC (Java Data Base Connectivity), rather than automatically laying themselves out, but it is a start. See CMP Business Classes.

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