USING THE CALCULATOR


The Calculator application is another one of those very simple and incredibly useful applications. It definitely takes some getting used to, but once you do, you will find yourself using it a lot. More than anything, it is just so handy to have it always on your hip.

If there is any application that doesn't look and feel like a BlackBerry application, this is it. Most of the other applications that we've looked at so far are text based and the screens are usually a collection of fields that display and collect text data. The Calculator application is mostly graphical however, and therefore most of the conventions we've seen so far do not apply here.

When you open the Calculator application, you see the screen, shown in Figure 13.8, with graphics and buttons that resemble a calculator like you might see on your desk.

Figure 13.8. Here's a look at the Calculator application.


Notice that one of the buttons is shown in reversed colored text. This is the current selection cursor like we have seen before. Scrolling the trackwheel up and down moves the section cursor from one button to the next. Clicking the trackwheel causes the button to be pressed and whatever action on it to be taken. For instance, if the 1 button is selected, clicking the trackwheel causes a 1 to be added to the display screen of the calculator.

Scrolling the trackwheel around to press buttons is time consuming and annoying. For this reason, each key on the calculator has a corresponding key on the keypad that will trigger the button. Of course pressing one of the keys with a number on it causes that number key to be pressed on the calculator. A few other keys have standard mappings that can be listed as well.

tip

Although there is not a backspace button on the calculator screen, pressing the Backspace key causes the number in the right-most position on the display to be erased.


  • + for addition

  • for subtraction

  • * for multiplication

  • / for division

  • Enter for equals

  • . for decimal point

Most of the other keys on the Calculator screen also have keys on the keypad that trigger them, but they can vary based on the devices. Below is a listing for the 7200 series of devices.

  • T key for Clear/Erase

    7100

    Because of the smaller keyboard, only the shortcuts using the asterisk, period, and Enter keys work on the 7100 series handhelds. The others must be selected by moving the cursor to the button on the screen and clicking the trackwheel.


  • Y key for Clear

  • H key for Memory Clear

  • J key for Memory Remember

  • K key for Memory Set

  • L key for Memory +

  • B key for percent

  • V key for square root

  • Q key for sign change (+/)

Because the trackwheel needs to be clicked to activate any of the buttons on the calculator, the standard mechanisms of clicking the trackwheel to display a menu cannot be done. Instead, there is a MENU button on the calculator and clicking the trackwheel while this button is selected causes the menu to be displayed.

A large set of conversion operations are available through the menu to convert to and from English and Metric systems of measurement. These operations are done just like any other operation is done on the calculator in that you must first enter the number to work with, and then select the operation. For instance, in order to convert 5 inches to centimeters, you would first click the 5 button, then the MENU button to display the menu. Click the To Metric menu item to display another menu of operations that convert from English to Metric, then click the in->cm menu item. Notice that the number in the calculator display has changed to 12.7, indicating that 5 inches is about equal to 12.7 centimeters.

note

Unfortunately, there is no keypad key that is the same as pressing the MENU button on the calculator. You must scroll the trackwheel to it each time.




Mobile Guide to BlackBerry
Mobile Guide to BlackBerry
ISBN: 0789733439
EAN: 2147483647
Year: 2006
Pages: 146
Authors: Bill Foust

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