TweetFollow Us on Twitter

June 94 - Newton Q & A: Ask the Llama

Newton Q & A: Ask the Llama

Newton Developer Techical Support

Q Here's something that's been puzzling me a bit: I want to pop up something like a copyright message for ten seconds when my application starts up. So I drew up a layout called Presents with a protoFloater containing all the necessary text. In my main layout is a link to Presents called presentsLink. The following is the viewShowScript for the topmost view in my application:

func()
begin
	presentsLink:open();
	AddDelayedAction(presentsLink:close(), nil, 10000)
end

This says to me: open the linked view, wait ten seconds, and close it. And that's exactly what it does, except that after the view is closed, there's an exception. What am I doing wrong and how do I fix it? 

The short answer is that the second argument to the AddDelayedAction function is of the wrong type. This argument is supposed to be an array of parameters to be passed to the delayed function, and nil is not an array. The proper syntax for no arguments is [] instead of nil.

But there's more: Although the closure you supplied in the first argument works in this case, you should get out of the habit of using that type of function call for delayed or deferred actions. You're better off providing a full closure and sending in the view you want closed, as in this:

func()
begin
	// Define a closure to use in the delayed action.
	local myClose := func(whichView)
		whichView:Close();

	presentsLink:Open();
	AddDelayedAction(myClose, [presentsLink], 10000);
end

Unfortunately, things do not end there. You also need to make sure that the myClose function is in internal RAM. The best way to do this is to use DefConst to define the function:

// In your ProjectData file:
DefConst('kDelayedClose, func(whichView) whichView:Close());

// This changes the function above:
func()
begin
	presentsLink:Open();
	AddDelayedAction(EnsureInternal(kDelayedClose),
		[presentsLink], 10000);
end

However, there is an easier solution. Instead of doing a delayed action you can use the view idle mechanism to do what you want. All you need to do is add a viewIdleScript and viewIdleFrequency to the presentsLink top-level view. The viewIdleScript simply sends a Close message. The viewIdleFrequency is set to the desired delay (10000 in this case).

The really short answer is that you can just use protoGlance. This proto has the show-and- disappear behavior built in. You can set the viewIdleFrequency to 10000 to get the behavior you want.

Q I have an alphabetically sorted list of items in a protoTable and I want to use protoa2z to quickly move through the table (like the cardfile overview). How do I do it? 

The first thing you need to do is find the index in the protoTable of the correct item (that is, find the right item in the def.tabValues array of the protoTable). How you do this will depend on what type of data you're representing. Then you can figure out how high each item in the protoTable is, set the VOrg slot of the table to the correct line, and force the protoTable to redraw. You probably want to make sure that you don't scroll off the bottom of the table. Below is a method you can add to your protoTable that will do what you want. You can then send the message from your a2zChanged method (make sure you send the message to the protoTable).

func(index)
begin
	// Figure out the height of an item in the table.
	local childHeight := if def.tabProtos.viewFont exists then
		fontHeight(def.tabProtos.viewFont)
	else
		fontHeight(viewFont);
	
	// Make sure that the table will not scroll off the end
	// by calculating the index of the bottommost item that
	// will be displayed.
	local largestIndex := def.tabDown - ((:LocalBox().bottom -
		:LocalBox().top) DIV childHeight) - 1;
	
	// Use the bottommost item (largestIndex) to make sure
	// the table has no empty space on the bottom.
	vOrg := MIN(index, largestIndex);
	
	// Now force the table to redraw.
	:RedoChildren();
end

Q I would like to use the protoa2z sample code in my application, but I can't figure out how to set the highlighted letter when the user scrolls through my data. 

It's easy once you realize that protoa2z is based on a protoPictIndexer. All you have to do is a SetValue of the currIndex slot to the correct index. This will change the highlighting of the protoa2z.

Note that using SetValue will not call the IndexClickScript, but this is probably what you want. If you do want it to be called, you'll have to manually unhighlight the current selection, set the currIndex slot, and then highlight the new item. The appropriate code would be

a2z:Unhilite();
a2z.currIndex := newIndex;
a2z:Hiliter(newIndex);

Q What is your quest? 

To answer the questions of those who develop for Newton.

Q I tried to use a protoPictRadioButton in my application but the highlight rectangle isn't the right size. I know that I need to write some code to draw the correct-sized highlight, but where do I hook it in? 

Minimally you need to override the viewDrawScript of the protoPictRadioButton. You may also want to change the viewFormat since it defaults to a thick rounded-rectangle border. Assuming that you wanted some sort of rectangle highlight around the selected button, you could use the following viewDrawScript:

func()
begin
	// If the button is selected, highlight it.
	if viewValue then
	begin
	// Get the bounds of the protoPictRadioButton.
	local b := :LocalBox();
	
	// Inset the bounds.
	b.top := b.top + 2;
	b.left := b.left + 2;
	b.bottom := b.bottom - 2;
	b.right := b.right - 2;
	
	// Now draw a rectangle.
	:DrawShape(MakeRect(b.left, b.top, b.right, b.bottom), nil);
	end;
end

Q What is the AutoClose checkbox in the Newton Toolkit for? Why should I use it? 

The AutoClose flag causes all other AutoClose applications to be closed when your application is clicked. The effect is that only one "auto-close" application can be open at one time. You should always  make your application auto-close, to help conserve memory and other resources, unless it's providing special functionality to other applications (like the built-in Calculator or Styles application).

Q How do I create my own class of binary object? 

To get a binary object of your own class, you first need to create a binary object, then change its class to your own. The easiest way to do this is to create a string that's the same length as your intended binary object and then change (coerce) the class of this new object to your own class. You can use the string class as your basic binary object.

Suppose you wanted to have a binary class called CharID for an ID consisting of four ASCII characters. You could write a NewID function in your ProjectData file that would create the object and optionally initialize it, like this:

// Define a constant for a default CharID object. This constant
// can be cloned at run time. kDefaultCharIDObj will be a CharID
// object with 4 bytes that are set to 0x00.
DefConst('kDefaultCharIDOBj, SetClass(SetLength("", 4),
         'CharID));

// CharString is a string of 4 characters or nil.
NewCharID := func(CharString)
begin
	// Create a binary object of the correct length.
	local newObj := Clone(kDefaultCharIDObj);
	
	// Optionally initialize it.
	if CharString then
	for i := 0 to 3 do
		StuffChar(newObj, i, CharString[i]);
	
	// Return the new object.
	newObj;
end;

To see this code in action, you can type it into the Inspector window in the Newton Toolkit and evaluate it. Note that you cannot use DefConst in the Inspector since it's a compile-time function. Just substitute the second argument in the DefConst function for kDefaultCharIDObj in the function to evaluate it. Then you can try things like this:
x := :NewCharID(nil);
#440DD01 <CharID, length 4>
ExtractChar(x, 2);
#6 $\00
x := NewCharID("abcd");
#4410FC9 <CharID, length 4>
ExtractChar(x, 2);
#636 $c
ExtractByte(x, 2);
#18C 99

Q What is your favorite color? 

Llama fur beige.

Q In my application I have a clPictureView that can display a variable number of pictures. Right now I create a bunch of picture slots in my application and then make another slot at run time that is an array of those items. There must be an easier way. 

You're right; there is an easier way. You can use the GetPictAsBits function in your ProjectData file to read in the bitmaps. Note that you'll first have to open the resource file that contains the pictures.

// Open the resource file that contains the pictures.
// Assumes the file "Pictures" exists in the project folder.
r := OpenResFileX("Pictures");

// Get an array of pictures.
myPictures := [
	GetPictAsBits("TARDIS", nil),
	GetPictAsBits("Planet", nil)
];

// Now close the resource file.
CloseResFileX(r);

Once you have the myPictures array, you can create a slot of type Evaluate and just type "myPictures" in the editor for the slot. Then you can use SetValue to set the icon slot of the clPicture view to one of the elements of the array.

Q How do I put my own default person in the fax information slip? 

You can set up a default person in your SetupRoutingSlip method, which is called before the fax slip is shown. The argument to that method is used to set up the particular routing slip. In the case of a fax slip, there's a slot called "alternatives" which is an array of cardfile entries for the possible people to fax to. If there's just one entry, that's the person. The fax number will be set from the cardfile entry. So your SetupRoutingSlip method would look like this:

func(fields)
begin
	// Check for a fax.
	if fields.category = 'faxSlip then
	fields.alternatives := SmartCFQuery("Llama");
	// Do other stuff here, like put a title for the out box.
end

Note that the fields.category is set to the same value you set in the routeSlip slot of a frame in your application's entry in the global routing frame. The SmartCFQuery function returns an array of cardfile entries that have strings starting with the string passed in.

Q I noticed that every soup entry has a _uniqueID slot. Just how unique is it? 

The _uniqueID slot is only unique within that soup on that particular store. The ID will never be reused in that soup on that store. However, it's not necessarily unique across stores (say, RAM and a PCMCIA card).

Q What is the ground velocity of an unladen llama climbing a 5% grade? 

What do you mean -- Mexican or Venezuelan?


The llama is Thanks Have more questions?

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

iClock 5.5 - Customizable menu bar clock...
iClock replaces the old Apple's default menu bar clock with more features, customization and increases your productivity. Features: Have your Apple or Google calendar instantly available from the... Read more
Garmin Express 6.18.0.0 - Manage your Ga...
Garmin Express is your essential tool for managing your Garmin devices. Update maps, golf courses and device software. You can even register your device. Update maps Update software Register your... Read more
MarsEdit 4.3.5 - Quick and convenient bl...
MarsEdit is a blog editor for OS X that makes editing your blog like writing email, with spell-checking, drafts, multiple windows, and even AppleScript support. It works with with most blog services... Read more
Xcode 11.0 - Integrated development envi...
Xcode includes everything developers need to create great applications for Mac, iPhone, iPad, and Apple Watch. Xcode provides developers a unified workflow for user interface design, coding, testing... Read more
DaisyDisk 4.8 - $9.99
DaisyDisk allows you to visualize your disk usage and free up disk space by quickly finding and deleting big unused files. The program scans your disk and displays its content as a sector diagram... Read more
VMware Fusion 11.5.0 - Run Windows apps...
VMware Fusion and Fusion Pro - virtualization software for running Windows, Linux, and other systems on a Mac without rebooting. The latest version includes full support for Windows 10, macOS Mojave... Read more
Apple Configurator 2.10 - Configure and...
Apple Configurator makes it easy to deploy iPad, iPhone, iPod touch, and Apple TV devices in your school or business. Use Apple Configurator to quickly configure large numbers of devices connected to... Read more
Spotify 1.1.15.448. - Stream music, crea...
Spotify is a streaming music service that gives you on-demand access to millions of songs. Whether you like driving rock, silky R&B, or grandiose classical music, Spotify's massive catalogue puts... Read more
MenuMeters 1.9.8 - CPU, memory, disk, an...
MenuMeters is a set of CPU, memory, disk, and network monitoring tools for Mac OS X. Although there are numerous other programs which do the same thing, none had quite the feature set I was looking... Read more
Blocks 3.5.2 - RapidWeaver plug-in; divi...
Blocks is a plugin for RapidWeaver. It allows you to place blocks of text, graphics, and even raw HTML onto your page wherever you like. Drag blocks around, resize them, and even overlap content. All... Read more

Latest Forum Discussions

See All

Marvel Strike Force is adding Agent Coul...
Marvel Strike Force, the popular squad-based RPG, is set to receive a bunch of new content over the next few weeks. [Read more] | Read more »
Lots of premium games are going free (so...
You may have seen over the past couple weeks a that a bunch of premium games have suddenly become free. This isn’t a mistake, nor is it some last hurrah before Apple Arcade hits, and it’s important to know that these games aren’t actually becoming... | Read more »
Yoozoo Games launches Saint Seiya Awaken...
If you’re into your anime, you’ve probably seen or heard of Saint Seiya. Based on a shonen manga by Masami Kurumada, the series was massively popular in the 1980s – especially in its native Japan. Since then, it’s grown into a franchise of all... | Read more »
Five Nights at Freddy's AR: Special...
Five Nights at Freddy's AR: Special Delivery is a terrifying new nightmare from developer Illumix. Last week, FNAF fans were sent into a frenzy by a short teaser for what we now know to be Special Delivery. Those in the comments were quick to... | Read more »
Rush Rally 3's new live events are...
Last week, Rush Rally 3 got updated with live events, and it’s one of the best things to happen to racing games on mobile. Prior to this update, the game already had multiplayer, but live events are more convenient in the sense that it’s somewhat... | Read more »
Why your free-to-play racer sucks
It’s been this way for a while now, but playing Hot Wheels Infinite Loop really highlights a big issue with free-to-play mobile racing games: They suck. It doesn’t matter if you’re trying going for realism, cart racing, or arcade nonsense, they’re... | Read more »
Steam Link Spotlight - The Banner Saga 3
Steam Link Spotlight is a new feature where we take a look at PC games that play exceptionally well using the Steam Link app. Our last entry talked about Terry Cavanaugh’s incredible Dicey Dungeons. Read about how it’s a great mobile experience... | Read more »
Combo Quest (Games)
Combo Quest 1.0 Device: iOS Universal Category: Games Price: $.99, Version: 1.0 (iTunes) Description: Combo Quest is an epic, time tap role-playing adventure. In this unique masterpiece, you are a knight on a heroic quest to retrieve... | Read more »
Hero Emblems (Games)
Hero Emblems 1.0 Device: iOS Universal Category: Games Price: $2.99, Version: 1.0 (iTunes) Description: ** 25% OFF for a limited time to celebrate the release ** ** Note for iPhone 6 user: If it doesn't run fullscreen on your device... | Read more »
Puzzle Blitz (Games)
Puzzle Blitz 1.0 Device: iOS Universal Category: Games Price: $1.99, Version: 1.0 (iTunes) Description: Puzzle Blitz is a frantic puzzle solving race against the clock! Solve as many puzzles as you can, before time runs out! You have... | Read more »

Price Scanner via MacPrices.net

Get one of Apple’s new 2019 iPhone 11 models...
Boost Mobile is offering the new 2019 Apple iPhone 11, iPhone 11 Pro, and 11 Pro Max for $100 off MSRP. Their discount reduces the cost of an iPhone 11 to $599 for the 64GB models, $899 for the 64GB... Read more
13″ 1.4GHz Silver MacBook Pros on sale for $1...
B&H Photo has new 2019 13″ 1.4GHz 4-Core Touch Bar Silver MacBook Pros on sale for $100 off Apple’s MSRP. Overnight shipping is free to many addresses in the US. These are the same MacBook Pros... Read more
4-core and 6-core 2018 Mac minis available at...
Apple has Certified Refurbished 2018 Mac minis available on their online store for $120-$170 off the cost of new models. Each mini comes with a new outer case plus a standard Apple one-year warranty... Read more
$250 prepaid Visa card with any Apple iPhone,...
Xfinity Mobile will include a free $250 prepaid Visa card with the purchase of any new iPhone, new line activation, and transfer of phone number to Xfinity Mobile. Offer is valid through October 27,... Read more
Sprint is offering the 64GB Apple iPhone 11 P...
Sprint has the new 64GB iPhone 11 Pro available for $12.50 per month for new customers with an eligible trade-in in of iPhone 7 or newer. That’s down from their standard monthly lease of $41.67. The... Read more
Final week: Apple’s 2019 Back to School Promo...
Purchase a new Mac using Apple’s Education discount, and take up to $400 off MSRP. All teachers, students, and staff of any educational institution with a .edu email address qualify for the discount... Read more
Save $30 on Apple’s AirPods at these reseller...
Amazon is offering discounts on new 2019 Apple AirPods ranging up to $30 off MSRP as part of their Labor Day sale. Shipping is free: – AirPods with Charging Case: $144.95 $15 off MSRP – AirPods with... Read more
Preorder your Apple Watch Series 5 today at A...
Amazon has Apple Watch Series 5 GPS models available for preorder and on sale today for $15 off Apple’s MSRP. Shipping is free and starts on September 20th: – 40mm Apple Watch Series 5 GPS: $384.99 $... Read more
21″ iMacs on sale for $100 off Apple’s MSRP,...
B&H Photo has new 21″ Apple iMacs on sale for $100 off MSRP with models available starting at $999. These are the same iMacs offered by Apple in their retail and online stores. Overnight shipping... Read more
2018 4 and 6-Core Mac minis on sale today for...
Apple resellers are offering new 2018 4-Core and 6-Core Mac minis for $100-$150 off MSRP for a limited time. B&H Photo has the new 2018 4-Core and 6-Core Mac minis on sale for up to $150 off... Read more

Jobs Board

Geek Squad *Apple* Master Consultation Agen...
**734380BR** **Job Title:** Geek Squad Apple Master Consultation Agent **Job Category:** Services/Installation/Repair **Location Number:** 000134-Dublin-Store **Job Read more
*Apple* Mobile Master - Best Buy (United Sta...
**727032BR** **Job Title:** Apple Mobile Master **Job Category:** Store Associates **Location Number:** 000356-Manassas-Store **Job Description:** **What does a Best Read more
*Apple* Mobility Pro - Best Buy (United Stat...
**733802BR** **Job Title:** Apple Mobility Pro **Job Category:** Store Associates **Location Number:** 000122-Las Vegas II-Store **Job Description:** At Best Buy, Read more
*Apple* Mobility Pro - Best Buy (United Stat...
**733541BR** **Job Title:** Apple Mobility Pro **Job Category:** Store Associates **Location Number:** 001180-Northridge-Store **Job Description:** At Best Buy, our Read more
*Apple* Mobile Master - Best Buy (United Sta...
**732324BR** **Job Title:** Apple Mobile Master **Job Category:** Store Associates **Location Number:** 000013-Fargo-Store **Job Description:** **What does a Best Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.