# Applet Toolkit 3.0.3

## UserLand Software, Inc.

### © copyright 1992-94, UserLand Software, Inc.

### UserLand Software is the developer of the UserLand Frontier scripting system. The company is located at 555 Bryant #237, Palo Alto, CA 94301. 415-326-7791, 415-326-7793 (fax). UserLand, Frontier, Frontier Runtime and Frontier Extras are trademarks of UserLand Software, Inc. Other product names may be trademarks or registered trademarks of their owners.

### Email: userland.dts@applelink.apple.com. If youÕre an AppleLink user, check out the UserLand Discussion Board under the Third Parties icon. CompuServe users enter GO USERLAND at any ! prompt. The UserLand Forum is in the Computing Support section on CompuServe. On America On-Line, enter the keyword USERLAND.

### Comments, questions and suggestions are welcome!

## Background

### The Applet Toolkit makes it simple to build new double-clickable Macintosh applications that have strong support for Apple Events and menu sharing.

### If youÕre developing a new application specifically to be integrated with other software, the Applet Toolkit is a perfect choice.

### UserLandÕs DocServer application is implemented using the Applet Toolkit, as are all new applications and utilities in development at UserLand.

### Two sample applications are provided. Minimal Applet is a simple multi-window text editor, BarChart is a color charting program.

## Sample Apps

### BarChart

#### The best way to learn about the Applet Toolkit is to examine an application that's built on it. BarChart is the simplest applet.

#### Open the BarChart.¹ project file and open barchart.c. Look at it's main () routine.

#### You'll see that it starts by clearing the app record and then setting a few fields:

##### clearbytes (&app, longsizeof (app)); /*init all fields to 0*/

##### app.creator = 'BARC';

##### app.filetype = 'CHRT';

##### app.usecolor = true;

##### app.resizeable = true;

#### This tells the Applet Toolkit to save newly created files with 'BARC' as their creator id, and to set the file type to 'CHRT'. Because BarChart sets the usecolor field to true, when new windows are created they will be color windows. Finally it says that BarChart's windows can be resized.

#### There are many other fields that BarChart could have set to allow for scroll bars, a tool palette, or a status area in each window that's created. See the definition of tyappletrecord in applet.h for complete information.

#### Then BarChart establishes a set of callback routines that are activated when certain events operations need to be performed. For example, when a window needs updating, bcupdate is called.

#### Finally it calls runapplet, which processes events and calls barchart.c callback routines when necessary.

### Minimal Applet

#### Despite its name, this program is a much more complete user of the Applet Toolkit than BarChart.

#### It supports horizontal and vertical scrolling, processes keystrokes and mouse events, and has real support for the clipboard.

## Applet Toolkit 3.0.3 -- 7/27/94 dmb

### Universal Headers, PowerPC compatibility

#### The Applet Toolkit can now be built using AppleÕs Universal Headers under Symantec C/C++ 7.0 or Metrowerks C/C++ 1.0 68K or PPC. Native or Òfat binaryÓ applications can be generated in the Code Warrior environment. Also, modern, ANSI-conformant function prototypes are used thoughout the code, so strict error checking can be enforced for Applet Toolkit projects.

## Applet Toolkit 3.0b10 -- 11/4/93 DW

### Lots of changes in the Applet Toolkit

#### Two new pieces of software in development at UserLand have forced the Applet Toolkit to become much more mature and complete, and more debugged. The changes in the Applet Toolkit arenÕt documented in this release. The Applet Toolkit is still very much a work in progress.

#### Following are notes taken while converting BarChart and MinApp to work with the new toolkit. Hopefully they will highlight any changes you need to make to convert your projects to the new version of the Applet Toolkit.

#### We also havenÕt tried too hard to hide where weÕre going. YouÕll see comments in the following section that talk about features that are not supported by this version of the toolkit, but will be supported in future versions.

#### Most notable is the next step in the evolution of ÒsharingÓ protocols. Eventually we will transition to a more powerful API called ÒUI Sharing,Ó which supports menu sharing, and window sharing. If youÕre interested, you can browse the Applet Toolkit to see how it will build on this new capability. Coming soon, we hope!

### Swap out UI Sharing calls, replace with menu sharing

#### UI sharing support is compiled only if ÒuiSharingÓ is defined, otherwise we use the Menu Sharing Toolkit.

### Replace appletcard.c with appletdialogs.c

#### Add appletabout.c.

### Turn on the Window menu

#### In barchart.c, sett app.haswindowmenu to true. Add a MENU 136 resource to barchart.¹.rsrc.

### Use temporary memory

#### In barchart.c, set app.usetempmemory to true.

### Smarter about overwriting grow box

#### BarChart is a wierd applet -- it has growable windows, but no scroll bars.

#### In barchart.c, bcupdate routine, we avoid erasing the windowÕs grow box.

### Build MinApp

#### Worked fine, the first time through.

#### Turned on temp memory and the Window menu, as with BarChart.

### Tweak up shared scripts

#### Took out msg call in 50 Upper/Lowers (want to see how fast it can be).

#### Insert 50 States inserts 50 strings instead of building up one string and inserting it.

#### Added ÒSystem Folder ListingÓ script. Nice!

### BarChart window updating

#### When you switch BarChart into the background itÕs supposed to redraw its highlighted window with a white background and fill the bars with a gray pattern. This isnÕt happening. Why?

#### There was a change in the Applet Toolkit (obviously!) -- instead of calling the activate callback when the applet is switched out, it calls a new callback routine, app.switchcallback. Fixed the problem by adding the following:

#####

##### app.switchcallback = (tyappbooleancallback) &bcactivate;

#####

#### to main () in barchart.c. The active window in BarChart now updates correctly.

### Disproportionate bars in BarChart

#### Peter Dako reports that when two bars in the same chart have wildly different values, like 18944 and 8580962, thereÕs some kind of problem displaying the chart. LetÕs see...

#### Found the problem, but didnÕt fix it. BarChart computes the height of the bars using integer arithmetic, and when you resize the window, the arithmetic can overflow, yielding negative numbers that should be positive. BarChart is a demo program.

#### I hear that DeltaGraph is scriptable!

###