TweetFollow Us on Twitter

Beginning REALBasic

Volume Number: 24 (2008)
Issue Number: 07
Column Tag: REALBasic

Beginning REALBasic

Designing the Application

by Norman Palardy

REALbasic is a Rapid Application Develpment (RAD) tool from REALSoftware. In previous columns we've looked at it briefly and even talked with Geoff Perlmann, the CEO of REAL Software. This month we're continuing our series of articles that aim to get you started with REALbasic and show you how to be productive with it. For this series we're using the latest version of REALbasic; version 2008r1.

Designing the Interface

In this installment we're creating an application that tracks the prices of stocks. This will involve accessing the Internet to grab quotes, graphs and a database. Some of the components required are built in to REALbasic itself, and others will have to come from third parties.

In this installment we'll design the interface, the database and the windows we'll need for adding stocks to track. We'll get started writing the basics that make the whole project come together.

First, start REALbasic so you have a new project to work with.


Figure 1. REALbasic default project

As we saw last month, this default project is a fully functioning program. You could immediately run it by pressing the green Run button.

Let's consider the tasks we'll need to accomplish to make this program work the way we want.

  • We'll need a way to add and remove stocks from the list of ones we're interested in.

  • It should keep quotes for any stocks we currently have, or had an interest in at any time

  • We'll need a way to view the current set of stocks we're interested in and their prices

  • We'll need a way to get the stock prices from a designated source

  • We'll need a way to designate which source we're going to read data from

  • Eventually we'll want a way to graph prices of stocks over time

That's a lot of things to consider so we'll tackle them one at a time. Lets start with how we show our list of stocks of interest.

In the project we created earlier, there should already be a window called Window1. Let's start by editing that window and altering its layout to turn it into one that shows our list of stocks.


Figure 2. Editing a REALbasic window

Down the left hand side is a list of the standard controls that are available in REALbasic. Note that I'm using the Professional version. The Personal version has a smaller set of controls.

In the center is the actual editor where you lay out the look of your window. On the right is the properties palette that displays the properties of the currently selected item.

First, rename this window so that at a glance, you can know which window it is. Click the window so it is selected as shown in Figure 2, and then click on the Name in the property list on the right. Name this window wStocks.

Then add a Listbox control to the window. Rename the listbox lstStocks and position and resize it so your window appears about like the one in Figure 3. Note that Figure 3 shows you the position and size of my listbox in the properties palette on the right hand side.

You'll also notice that the listbox has several lock properties set (LockLeft, LockRight, LockTop, LockBottom). These properties tell REALbasic to keep the listbox "locked" to the respective sides of the window if the window is resized.


Figure 3. Create the stock list window

If you run the project at this point you wont see much except that a window with a large white area shows up. That area is the listbox, which is empty at this point.

The question, then, is how to fill it with data and what data to fill it with.

Every control has a number of "events" that allow you provide custom code when something (an event) occurs. Different controls have different events. The list of events that exist for a control varies depending on what kind of control it is. Simple controls have few events. Timers only have one event. The listbox has a fairly long list of events. For our program let's start with just using the Open event.

This event occurs when the control is about to be shown on a window that is being opened. It occurs only once when the window is initially opened. There are other events that occur more frequently but for the start of this project we'll use this event.

One thing to be aware of is that event ordering is generally not something you want to rely on. You have no idea if the listbox Open event occurs before or after some other controls Open event. The other control may not even exist yet. So you have to be careful about how you use certain events and what you try to do in the code for that event.

If you double-click the listbox you will be shown the code editor. REALbasic also tries to be helpful and selects the most likely event you are going to want to edit. In this case that's the Change event for the list box.


Figure 4. Editing the listbox events in the stock list window

Select the Open event in the left hand pane and then add the following code :

  me.ColumnCount = 3 // change the number of visible columns
  me.HasHeading = true // make the list box have a leading row
  me.Heading(0) = "Symbol" // set the heading for the first column
  me.Heading(1) = "Time" // set the heading for the second column
  me.Heading(2) = "$" // set the heading for the third column

Much of this CAN be done without writing code. If you review figure 3, you'll see that in the right hand properties pane there are settings for ColumnCount, HasHeading and InitialValue. If you set the columnCount property to 3 then the listbox will have 3 columns. If you check HasHeading then the listbox will have a heading and the setting for InitialValue will be used as the column headings. We've done these things in the Open event simply to illustrate that you can change some properties on the fly and they will take effect right away. Being able to alter the number of columns and their headings at run time will be shown in future articles.

If you run the program now, you can see that when the window opens it has 3 columns with the headings we wanted.

Now we have a way to get the display looking like what we want, so now let's see about getting some rows into it that display data.

If you look up ListBox in the built-in Language Reference, you'll see it has numerous events, properties and methods. Again, an event is some piece of code that gets run when something happen; a person selects a row, clicks a button or presses a key. Properties are the "settings" of various aspects of the control; the number of columns, which row is selected, or other display related values like the text font and size.

Methods are behaviors that the listbox will perform. These are actions like adding a row (AddRow), remove a row (RemoveRow), or ways to get data from the listbox (Cell and CellTag).

For our use AddRow is the one we need at present. At the end of the open event add the following code :

  me.AddRow "AAPL" // add one symbol we're interested in watching
  dim newDate as new Date // create a new instance of a Date
  me.cell(me.LastIndex,1) = newDate.ShortDate + " " + newDate.ShortTime // add the date / time stamp
  me.cell(me.LastIndex,2) = format(169.73,"$,#.00") // display Apple's current value

Let's review this code closely.

  me.AddRow "AAPL" // add one symbol we're interested in watching

This line adds the data for the first cell (the left most one also known as column 0) and leaves the other cells empty.

  dim newDate as new Date

For the second column we want the current date and time. In order to get that information we need to create an instance of a Date object, which is conveniently initialized to the date and time from the OS when the instance was created. A Date instance is not a clock and does not automatically count forward.

 me.cell(me.LastIndex,1) = newDate.ShortDate + " " + newDate.ShortTime // add the date / time stamp

Then we fill the middle cell — the one we want to contain the date and time — by using the CELL method to refer to a specific cell. Note that in order to make sure we set the correct cell in the correct row there is a convenient property called "lastIndex" that is the row number that was last added. The code says "set the last rows cell 1 to the short date and short time" which is exactly what we want.

  me.cell(me.LastIndex,2) = format(169.73,"$,#.00")

For the last column, column 2, we want a value. But the listbox only knows how to display strings. So we have to take the current value of Apple's stock, 169.73, which is a number and convert it into a string that the listbox can display. Also, we want to make sure the string that the listbox displays is formatted so it looks just the way we want. To do that we use the FORMAT method which gives us control over how numbers look when they are converted to strings.

Run this now and you'll see we're making headway. We can make the listbox display data, and we can add data to it.

Next time we'll look at how to make the data that we display more dynamic and actually get it from a web based quote service like Yahoo finance.


Norman Palardy has worked with SQL databases since 1992, and has programmed in C, C++, Java, REALbasic and other languages on a wide variety of platforms. In his 15+ years of IT experience, Norman has developed innovative and award-winning applications for TransCanada Pipelines, Minerva Technologies (now XWave), Zymeta Corporation, and the dining and entertainment industry. He holds a BSc from the University of Calgary in Alberta. He's also the Vice President of the Association of REALbasic Professionals (http://www.arbp.org)

 

Community Search:
MacTech Search:

Software Updates via MacUpdate

FotoMagico 5.6.12 - Powerful slideshow c...
FotoMagico lets you create professional slideshows from your photos and music with just a few, simple mouse clicks. It sports a very clean and intuitive yet powerful user interface. High image... Read more
OmniGraffle Pro 7.12.1 - Create diagrams...
OmniGraffle Pro helps you draw beautiful diagrams, family trees, flow charts, org charts, layouts, and (mathematically speaking) any other directed or non-directed graphs. We've had people use... Read more
beaTunes 5.2.1 - Organize your music col...
beaTunes is a full-featured music player and organizational tool for music collections. How well organized is your music library? Are your artists always spelled the same way? Any R.E.M. vs REM?... Read more
HandBrake 1.3.0 - Versatile video encode...
HandBrake is a tool for converting video from nearly any format to a selection of modern, widely supported codecs. Features Supported Sources VIDEO_TS folder, DVD image or real DVD (unencrypted... Read more
Macs Fan Control 1.5.1.6 - Monitor and c...
Macs Fan Control allows you to monitor and control almost any aspect of your computer's fans, with support for controlling fan speed, temperature sensors pane, menu-bar icon, and autostart with... Read more
TunnelBear 3.9.3 - Subscription-based pr...
TunnelBear is a subscription-based virtual private network (VPN) service and companion app, enabling you to browse the internet privately and securely. Features Browse privately - Secure your data... Read more
calibre 4.3.0 - Complete e-book library...
Calibre is a complete e-book library manager. Organize your collection, convert your books to multiple formats, and sync with all of your devices. Let Calibre be your multi-tasking digital librarian... Read more
Lyn 1.13 - Lightweight image browser and...
Lyn is a fast, lightweight image browser and viewer designed for photographers, graphic artists, and Web designers. Featuring an extremely versatile and aesthetically pleasing interface, it delivers... Read more
Visual Studio Code 1.40.0 - Cross-platfo...
Visual Studio Code provides developers with a new choice of developer tool that combines the simplicity and streamlined experience of a code editor with the best of what developers need for their... Read more
OmniGraffle 7.12.1 - Create diagrams, fl...
OmniGraffle helps you draw beautiful diagrams, family trees, flow charts, org charts, layouts, and (mathematically speaking) any other directed or non-directed graphs. We've had people use Graffle to... Read more

Latest Forum Discussions

See All

The House of Da Vinci 2 gets a new gamep...
The House of Da Vinci launched all the way back in 2017. Now, developer Blue Brain Games is gearing up to deliver a second dose of The Room-inspired puzzling. Some fresh details have now emerged, alongside the game's first official trailer. [Read... | Read more »
Shoot 'em up action awaits in Battl...
BattleBrew Productions has just introduced another entry into its award winning, barrelpunk inspired, BattleSky Brigade series. Whilst its previous title BattleSky Brigade TapTap provided fans with idle town building gameplay, this time the... | Read more »
Arcade classic R-Type Dimensions EX blas...
If you're a long time fan of shmups and have been looking for something to play lately, Tozai Games may have just released an ideal game for you on iOS. R-Type Dimensions EX brings the first R-Type and its sequel to iOS devices. [Read more] | Read more »
Intense VR first-person shooter Colonicl...
Our latest VR obsession is Colonicle, an intense VR FPS, recently released on Oculus and Google Play, courtesy of From Fake Eyes and Goboogie Games. It's a pulse-pounding multiplayer shooter which should appeal to genre fanatics and newcomers alike... | Read more »
PUBG Mobile's incoming update bring...
PUGB Mobile's newest Royale Pass season they're calling Fury of the Wasteland arrives tomorrow and with it comes a fair chunk of new content to the game. We'll be seeing a new map, weapon and even a companion system. [Read more] | Read more »
PSA: Download Bastion for free, but wait...
There hasn’t been much news from Supergiant Games on mobile lately regarding new games, but there’s something going on with their first game. Bastion released on the App Store in 2012, and back then it was published by Warner Bros. This Warner... | Read more »
Apple Arcade: Ranked - 51+ [Updated 11.5...
This is Part 2 of our Apple Arcade Ranking list. To see part 1, go here. 51. Patterned [Read more] | Read more »
NABOKI is a blissful puzzler from acclai...
Acclaimed developer Rainbow Train's latest game, NABOKI, is set to launch for iOS, Android, and Steam on November 13th. It's a blissful puzzler all about taking levels apart in interesting, inventive ways. [Read more] | Read more »
A Case of Distrust is a narrative-driven...
A Case of Distrust a narrative-focused mystery game that's set in the roaring 20s. In it, you play as a detective with one of the most private eye sounding names ever – Phyllis Cadence Malone. You'll follow her journey in San Francisco as she... | Read more »
Brown Dust’s October update offers playe...
October is turning out to be a productive month for the Neowiz team, and a fantastic month to be a Brown Dust player. First, there was a crossover event with the popular manga That Time I Got Reincarnated as a Slime. Then, there was the addition of... | Read more »

Price Scanner via MacPrices.net

Score a 37% discount on Apple Smart Keyboards...
Amazon has Apple Smart Keyboards for current-generation 10″ iPad Airs and previous-generation 10″ iPad Pros on sale today for $99.99 shipped. That’s a 37% discount over Apple’s regular MSRP of $159... Read more
Apple has refurbished 2019 13″ 1.4GHz MacBook...
Apple has a full line of Certified Refurbished 2019 13″ 1.4GHz 4-Core Touch Bar MacBook Pros available starting at $1099 and up to $230 off MSRP. Apple’s one-year warranty is included, shipping is... Read more
2019 13″ 1.4GHz 4-Core MacBook Pros on sale f...
Amazon has new 2019 13″ 1.4GHz 4-Core Touch Bar MacBook Pros on sale for $150-$200 off Apple’s MSRP. These are the same MacBook Pros sold by Apple in its retail and online stores: – 2019 13″ 1.4GHz/... Read more
11″ 64GB Gray WiFi iPad Pro on sale for $674,...
Amazon has the 11″ 64GB Gray WiFi iPad Pro on sale today for $674 shipped. Their price is $125 off MSRP for this iPad, and it’s the lowest price available for the 64GB model from any Apple reseller. Read more
2019 15″ MacBook Pros available for up to $42...
Apple has a full line of 2019 15″ 6-Core and 8-Core Touch Bar MacBook Pros, Certified Refurbished, available for up to $420 off the cost of new models. Each model features a new outer case, shipping... Read more
2019 15″ MacBook Pros on sale this week for $...
Apple resellers B&H Photo and Amazon are offering the new 2019 15″ MacBook Pros for up to $300 off Apple’s MSRP including free shipping. These are the same MacBook Pros sold by Apple in its... Read more
Sunday Sale: AirPods with Wireless Charging C...
B&H Photo has Apple AirPods with Wireless Charging Case on sale for $159.99 through 11:59pm ET on November 11th. Their price is $40 off Apple’s MSRP, and it’s the lowest price available for these... Read more
Details of Sams Club November 9th one day App...
Through midnight Saturday night (November 9th), Sams Club online has several Apple products on sale as part of their One Day sales event. Choose free shipping or free local store pickup (if available... Read more
Sprint is offering the 64GB Apple iPhone 11 f...
Sprint has the new 64GB iPhone 11 available for $15 per month for new lines. That’s about 50% off their standard monthly lease of $29.17. Over is valid until November 24, 2019. The fine print: “Lease... Read more
New Sprint November iPhone deal: Lease one iP...
Switch to Sprint and purchase an Apple iPhone 11, 11 Pro, or 11 Pro Max, and get a second 64GB iPhone 11 for free. Requires 2 new lines or 1 upgrade-eligible line and 1 new line. Offer is valid from... Read more

Jobs Board

*Apple* Mobility Pro - Best Buy (United Stat...
**746087BR** **Job Title:** Apple Mobility Pro **Job Category:** Store Associates **Store NUmber or Department:** 000319-Harlem & Irving-Store **Job Description:** Read more
Best Buy *Apple* Computing Master - Best Bu...
**743392BR** **Job Title:** Best Buy Apple Computing Master **Job Category:** Store Associates **Store NUmber or Department:** 001171-Southglenn-Store **Job Read more
Best Buy *Apple* Computing Master - Best Bu...
**746015BR** **Job Title:** Best Buy Apple Computing Master **Job Category:** Sales **Store NUmber or Department:** 000372-Federal Way-Store **Job Description:** Read more
*Apple* Mobility Pro - Best Buy (United Stat...
**744658BR** **Job Title:** Apple Mobility Pro **Job Category:** Store Associates **Store NUmber or Department:** 000586-South Hills-Store **Job Description:** At Read more
Best Buy *Apple* Computing Master - Best Bu...
**741552BR** **Job Title:** Best Buy Apple Computing Master **Job Category:** Sales **Store NUmber or Department:** 000277-Metcalf-Store **Job Description:** **What Read more
All contents are Copyright 1984-2011 by Xplain Corporation. All rights reserved. Theme designed by Icreon.