iPhone Application Lifecycle

I just went through one presentation for iPhone application. So this post to share what I understood.
First of all the main focus is how actually iPhone applications work.
When user touches the icon of the application main() gets called by the system.
main() creates the autoreleasepool and starts the application with UIApplicationMain object. UIApplicationMain creates the instance of the UIApplication which actually starts the application.
UIApplication loads the main nib file and sets the application. Then UIApplication forwards the events to interface elements.
For terminating the application user taps home button, UIApplication tells the delegate that application is terminating. And so UIApplication gets exited , then main gets exited. This way the process ends.
This is the way iPhone applications works.
Happy coding…..!!!!

 

converting Float to NSString

Float myFloat=3.85;

NSString *myString = [NSString stringWithFormat:@”%f”, myFloat];

Conversion Formulas

BEGIN WITH FORMULA for CONVERTING
(Multiply Number of Units by Conversion Number to Obtain New Number of Units)
millimeters (mm) millimeters x 0.03937 = inches
centimeters (cm) centimeters x 10 = millimeters
centimeters x 0.3937 = inches
meters (m) meters x 1000 = millimeters
meters x 100 = centimeters
meters x 3.281 = feet
meters per second x 3.281 = feet per second
square meters x 10.76 = square feet
square meters x 1.196 = square yards
square meters x 0.0002471 = square acres
cubic meters x 35.31 = cubic feet
cubic meters x 1.308 = cubic yards
cubic meters x 0.0008107 = acre-feet
cubic meters per second x 35.31 = cubic feet per second
cubic meters per second x 15,850.00 = gallons per minute
kilometers (km) kilometers x 1000 = meters
kilometers x 0.6214 = miles
square kilometers x 0.3861 = square miles
cubic kilometers x 0.2399 = cubic miles
inches (in) inches x 25.4 = millimeters
inches x 2.54 = centimeters
square inch x 6.4516 = square centimeters
feet (ft) feet x 12 = inches
feet x 0.3048 = meters
square feet x 0.09294 = square meters
cubic feet x 0.02832 = cubic meters
acre-foot x 1233 = cubic meters
yard (yd) yard x 3 = feet
yard x 0.9144 = meters
miles (mi) miles x 5280 = feet
miles x 1609.3 = meters
miles x 1.609 = kilometers
square miles x 2.590 = square kilometers
cubic miles x 4.168 = cubic kilometers
acre-foot (acre-ft) acre-ft x 1233 = cubic meters
microradian microradian x 0.2 = second of arc
Temperature Conversions
degrees Fahrenheit (F)
degrees Celsius (C) (F – 32) x 5/9 = C
(C x 1.8) + 32 = F
(C x 2) – (C x 2 x 0.1) + 32 = F
a) double the Celsius temperature
b) subtract 10% of the doubled temperature
c) add 32
Weights and Measures
(Left Column Equals Right Column)
1 cup = 8 fluid ounces = 4.8 ounces = 137 grams dry weight
= 8 ounces
= 16 tablespoons
= 48 teaspoons
1 gallon = 0.1337 cubic feet
= 231 cubic inches
= 3.785 liters
= 8.336 pounds of water
= 133.376 ounces of water
1 liter = 0.001 cubic meter
= 1.057 quarts
= 0.2642 gallons
= 0.03531 cubic feet
1 ounce = 0.0625 pounds
= 28.35 grams
= 437.5 grains
1 pound (Avoirdupois) = 16 ounces
= 0.4536 kilograms
= 7000 grains
= 1.2153 pounds Troy
1 quart = 2 pints
= 0.25 gallons
= 0.9464 liters
= 2.084 pounds of water