Ios Development Notes

Front 1

ARC def + abbr

Back 1

ARC - Automatic Reference Counting

ARC provides automatic object-lifetime management for your app, ensuring that objects remain in existence for as long as they're needed and no longer.

Front 2

Delegation as a design pattern

Back 2

Delegation is a design pattern in which one object acts on behalf of, or in coordination with, another object.

Front 3

Info.plist file is an (def)

Back 3

information property list—that is, a structured list of key-value pairs that contains information about the app such as its name and icon

Front 4

main function in main.m calls the UIApplicationMain function within an autorelease pool

Back 4

@autoreleasepool {
return UIApplicationMain(argc, argv, nil, NSStringFromClass([HelloWorldAppDelegate class]));
}

Front 5

@autoreleasepool {
return UIApplicationMain(argc, argv, nil, NSStringFromClass([HelloWorldAppDelegate class]));
}

explain

Back 5

call to UIApplicationMain creates an instance of the UIApplication class and an instance of the app delegate
he main job of the app delegate is to provide the window into which your app’s content is drawn. The app delegate can also perform some app configuration tasks before the app is displayed.

Front 6

In an iOS app, a window object provides a ?

Back 6

In an iOS app, a window object provides a container for the app’s visible content, helps deliver events to app objects, and helps the app respond to changes in the device’s orientation. The window itself is invisible.

Front 7

storyboard contains (def)

Back 7

storyboard contains an archive of the objects, transitions, and connections that define an app’s user interface.

Front 8

view controller (def)

initial view controller (def)

Back 8

view controller - is an object that manages an area of content

initial view controller - is simply the first view controller that gets loaded when an app starts.

Front 9

view (def)

Back 9

A view is an object that draws content in a rectangular area of the screen and handles events caused by the user’s touches. A view can also contain other views, which are called subviews

Front 10

subviews (def)

Back 10

hen you add a subview to a view, the containing view is called the parent view and its subview is called a child view. The parent view, its child views (and their child views, if any) form a view hierarchy. A view controller manages a single view hierarchy.

Front 11

MVC

Back 11

MVC - Model-View-Controller

Front 12

segue def

Back 12

represents a transition between two scenes.

Front 13

initial scene indicator def

Back 13

initial scene indicator, which identifies the scene that should be loaded first when the app starts (typically, the initial scene is the same as the initial view controller).

Front 14

first responder

Back 14

a dynamic placeholder that represents the object that should be the first to receive various events while the app is running. These events include editing-focus events, motion events, and action messages (such as the message a button sends when the user taps it), among others.

Front 15

create map

Back 15

_MapView.mapType= MKMapTypeSatellite;
MKCoordinateRegion newRegion;
newRegion.center.latitude = 38.880816;
newRegion.center.longitude = -77.102156;
newRegion.span.latitudeDelta = 0.234921;
newRegion.span.longitudeDelta = 0.528374;

[self.MapView setRegion:newRegion animated:YES];

Front 16

pin for map

Back 16

MKPointAnnotation *annotation = [[MKPointAnnotation alloc] init];
[annotation setCoordinate:coordinate];
[annotation setTitle:@"BAU - DEbich"];
[self.MapView removeAnnotations: self.MapView.annotations];
[self.MapView addAnnotation:annotation];

Front 17

Basic modes for interface controls

Back 17

active - basic button
static - dont trigger events
passive - text field on a web page, user can interact and change their value but they dont trigger event

Front 18

All iOS controls are sub-classes of

Back 18

UIControl

Front 19

create a string appending a string variable title to it

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statusText.text = [NSString stringWithFromat:@"%@ button pressed.", title];

"append button press."

Front 20

string declaration

Back 20

NSString *title;

Front 21

application delegate files (list)

Back 21

<*>AppDelegate.h
<*>AppDelegate.m

Front 22

delegates (aka application delegates) - def

Back 22

classes that take responsibility for doing certain tasks on behalf of another objects
The application delegate lets us do things at certain predefined time on behalf of the UIApplication class

Front 23

UIApplication class

Back 23

every iOS application has only one instance of UIApplication, responsible for the application;s run loop and handles application-level functionality such as routing input to the appropriate contoroller class

Front 24

Always use tag property to get an UI element

Back 24

We dont want to use the name of the UI element in case we change the language
The Tag is a numerical value

Front 25

Opaque option in Interface Builder

Back 25

tells iOS that nothing behind your view needs to be drawn => iOS's drawing methods will optimize the drawing speed

Front 26

Clears Graphics Context option in Interface Builder

Back 26

When it is checked, iOS will draw the entire are covered by the object in transparent black before it actually draws the object.
Turn it of for performance improvement

Front 27

Clip Subviews option in Interface Builder

Back 27

When our view contains subviews, and those subviews are not completely contained within the bounds of its parent view if
checked: only portions of subviews that lie within the bounds of the parent will be drawn
unchecked: subviews will be drawn completely

Front 28

Closing the keyboard when done is tapped

Back 28

Keyboard is software based => we need to tell the text field to give up control so keyboard can go away.

When done is pressed DidEndOnExit event will be generated.
In <*>ViewController.h add
- (IBAction)textFieldDoneEditing: (id)sender;
In <*>ViewController.h add
- (IBAction)textFieldDoneEditing:(id)sender }
[self.sender resignFirstResponder];
}

In Connections connect DidEndOnExit - drag to File's Owner and connect to textFieldDoneEditing

Front 29

First responder (def)

Back 29

the first responder is the control with which the user is currently interacting

Front 30

Sample how to release control when background is tapped (useful for hiding keyboard on text fields)

Back 30

in *.h add -(IBAction)backgroundTap:(id)sender;
in *.m -(IBAction)bacgroundTap:(id)sender {
[self.nameField resignFirstResponder];
[self.numberField resignFirstResponder];
}

in identity inspector change UIView underlying class to UIControl (by doing this we added all "button"/control events to our view)

from connection drag on Touch Down to File's Owner icon and select backgroundTap

Front 31

Create a sting formatted with combination of string and interger and set is as text for a labelSlider

Back 31

self.labelSlider.text = [NSString stringwithFormat:@"Value:%d", variable)

Front 32

How to get the current sender

Back 32

in 8.m
-(IBAction)switchToggled:(id)sender {
UISwitch *whichSwitch = (UISwitch *)sender;
....
-(IBAction)sliderChanged:(id)sender {
UISlider *slider = (UISlider *)sender;
....

Front 33

Get switch state

Back 33

-(IBAction)switchChanged:(id)sender {
UISwitch *whichSwitch = (UISwitch *)sender;
BOOL setting = whichSwitch.isOn;
[self.leftSwitch setOn:setting animated:YES];
[self.leftRight setOn:setting animated:YES];
}

Front 34

How to see what Segment was selected form a Segmented Control

Back 34

-(IBAction)toggleControls:(id)sender {
if ([sender selectedSegmentIndex] == 0) {
doSomethingButton.hidden = YES;
} else {
doSoemthingButton.hidden = NO;
}
}

Front 35

Set hidden on a control on an outlet

Back 35

in *.h
@property (weak, nonatomic) IBOutlet UIButton *doSomethingButton;

in *.m

doSomethingButton.hidden = YES;

Front 36

action sheet (def)

Back 36

used to force user to make a choice
user is unable to use the application until the have tapped on of the option

Front 37

alerts (def)

Back 37

appear as blue rounded rectangles in the middle of the scree.
force users to respond before they are allowed to continue using the app
more informative and more important messages
only single button can be presented

Front 38

modal view (def)

Back 38

a view that forces users to make a choice before they are allowed to continue using their application is known as modal view

Front 39

create and show the action sheet

Back 39

- (IBAction)buttonPressed:(id)sender {
UIActionSheet *actionSheet = [[UIActionSheet alloc]
initWithTitel:@"Are you sure"
delegate:self
cancelButton:@"No Way!"
destructiveButtonTitle:@"Yes, I'm sure!"
otherButtonTitels:nil];
[actionSheet showInView:self.view];
}

Front 40

how to initialize an alert

Back 40

UIAlertView *alert = [[UIAlertView alloc]
initWithTitle:@"Something was done"
message:msg
delegate:self
cancelButtonTitle:@"Phew!"
otherButtonTitles:nil];
];

[alert show]; //will cause the alert to be displayed

Front 41

stretchable images (def)

end caps (def)

Back 41

a re-sizable image that know how to re-size itself intelligently so that it maintain the correct appearance

part of an image (measured in px) that should not be resized

Front 42

iPhone/iPod touch resolution dimension
iPad
status bar dimension

Back 42

320 x 480
768 x 1024
20 px

Front 43

retina display def and dimension

Back 43

term for the high res screen on iPhone 4/4s

640 x 960

Front 44

approaches for auto rotation

Back 44

autosize attributes for simpler interfaces
manual re-positioning of objects in view when notified that view is rotating
actually design tow different version of view (1 for portrait/1 for landscape)

Front 45

What plist file contains information about the orientation supported by our app

Back 45

Auosize-Info.plist
in the Supporting Files

an entry called either UISupportedInterfaceOrientation or Supported Interface Orientation

Front 46

What method is called automatically after a rotation has happened but before the final rotation animations have occured

Back 46

willAnimateRotationToInterfaceOrientation:duration in BIDViewController.m

Front 47

The size and position of all views, including controls such as buttons, are specified in a property called ______, which is a struct of type ______

Back 47

frame
CGRect

CGReckMake is a function provided by apple that lets you specify the x and y position along with the width/height of an element

Front 48

define C macro

Back 48

#define degreesToRadians(x) (M_PI * (x) / 180.0)

Front 49

upgraded to Xcode 4.3 from 4.2 and it seems they have gotten rid of the New File option to add a UIViewController subclass in 4.2

and in 4.3

Back 49

4.2
File => New File... => Cocoa Touch => UIViewController subclass.

4.3
File => New File... => Cocoa Touch => Objective-C class => choose "subclass of" UIViewController.

Front 50

This callback occurs when the view controller is rotating to a new orientation. It looks at the orientation the view controller is rotating to and resizes the views appropriately – in this case with hardcoded offsets based on the known screen dimensions of the iPhone. This callback occurs within an animation block, so the changes in size will animate.

Back 50

(void)willAnimateRotationToInterfaceOrientation:(UIInterfaceOrientation)toInterfaceOrientation
duration:(NSTimeInterval)duration

Front 51

autosizing masks aka ? + def

Back 51

known as the “springs and struts” model

autosizing mask determines what happens to a view when its superview changes size. Does it have flexible or fixed margins (the struts), and what happens to its width and height (the springs)

Front 52

turn AutoSizeing off

Back 52

select *.nib/xib
select file inspector
uncheck "Use Autolayout"

Auto Layout is available only in iOS 6

Front 53

custom view handling between landscape and portrait mode

Back 53

connect each view to ViewController.h
over wride the - (void)WillAnimateRotationToInterfaceOrientation:(UIInterfaceOrinetation)toInterfaceOrientation duration:(NSTimeInterval)duration

Front 54

Constraints are objects of what class

Back 54

NSLayoutConstraint

Front 55

intrinsic content size def

Back 55

element that know how wide it must be
UIButton and UILabel are intrinsic

Front 56

Typically you would override _______________________ to change the frames of any views that need to be rearranged.

Back 56

willAnimateRotationToInterfaceOrientation:duration:

Front 57

Check if button's title is equal to X and change it to "A very long title for this button" other wise set it to X

Back 57

- (IBAction)buttonTapped:(UIButton *)sender
{
if ([[sender titleForState:UIControlStateNormal] isEqualToString:@"X"])
[sender setTitle:@"A very long title for this button"
forState:UIControlStateNormal];
else
[sender setTitle:@"X" forState:UIControlStateNormal];
}

Front 58

animation curve def

Back 58

determines the timing of the animation.
default is a linear curve, causes the animation to happen at a constant speed

[UIView setAnimationCurve: UIViewAnimationCurveEaseInOut];

4 iOS transition are available

UIViewAnimationTransitionFlipFromLeft
UIViewAnimationTransitionFlipFromRigh
UIViewAnimationTransitionCurlUp
UIViewAnimationTransitionCurlDown

Front 59

header file sample

Back 59

#imports
@interface <nameofclass> : <parentobject>
{
...
}
@end

Front 60

NSObject requires what heather file

Back 60

Reuqires Foundation framework

#import <Foundation/Foundation.h>

Front 61

All classes in Objective C have _________________ and _____________

Back 61

header files
implementation files

and the header file is the public API

Front 62

- (void)setOperand:(double)anOperand;
vs
-setOperand:(double)anOperand;

Back 62

with (void) method returns void

without anything returns an object

Front 63

pointer to an object (string)

Back 63

(NSString *)operation;

Always allocated on the heap

Front 64

- (NSArray *)foo: (int) bar:(id)pow;

how is this method called and how many arguments it takes

Back 64

takes two arguments and is called foo:bar:
(foo colon bar colon)

Front 65

Determining whether you’re compiling for a simulator

Back 65

#if TARGET_IPHONE_SIMULATOR
NSString *hello = @"Hello, iOS Simulator!";
#else
NSString *hello = @"Hello, iOS device!";
#endif

Front 66

how to use the TARGET_OS_IPHONE macro in a source file to be shared between Mac OS X and iOS

Back 66

#if TARGET_OS_IPHONE
#import <UIKit/UIKit.h>
#else
#import <Cocoa/Cocoa.h>
#endif

Front 67

The TARGET_OS_IPHONE and TARGET_IPHONE_SIMULATOR macros are defined in the _____________________ header file.

Back 67

TargetConditionals.h header file.