通常我們會用 UI_USER_INTERFACE_IDIOM 來做檢查
(UI_USER_INTERFACE_IDIOM() == UIUserInterfaceIdiomPad)
但如果 xCode Project Devices 沒有選 iPad 或是 Universal 這招就會失效，
只好改用判斷 model 的方式來處理。
([[[UIDevice currentDevice] model] rangeOfString:@"iPhone"].location == NSNotFound)
xCode 6.1
$> defaults read /Applications/Xcode.app/Contents/Info DVTPlugInCompatibilityUUID
C4A681B0-4A26-480E-93EC-1218098B9AA0
// ie: http://todolist?tk=tokenString&did=123-321-111-222-333&account=0DD3223&id=3547
- (BOOL)application:(UIApplication *)application openURL:(NSURL *)url sourceApplication:(NSString *)sourceApplication annotation:(id)annotation
{
if ([[url scheme] isEqualToString:@"todolist"]) {
NSString *query = [url query];
if (query.length > 0) {
NSArray *components = [query componentsSeparatedByString:@"&"];
NSMutableDictionary *parameters = [[NSMutableDictionary alloc] init];
for (NSString *component in components) {
NSArray *subcomponents = [component componentsSeparatedByString:@"="];
[parameters setObject:[[subcomponents objectAtIndex:1] stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding]
forKey:[[subcomponents objectAtIndex:0] stringByReplacingPercentEscapesUsingEncoding:NSUTF8StringEncoding]];
}
return YES;
}
}
return NO;
}
iOS8 有提供一個新的功能 App Groups，可以讓兩個獨立的 app 互相共享資料
接下來用 NSUserDefaults initWithSuiteName 初始化，就可以進行簡單的共享資料。
//var myShareDefaults = NSUserDefaults(suiteName: "group.com.xxx.AppGroupsDemo")
NSUserDefaults *myShareDefaults = [[NSUserDefaults alloc] initWithSuiteName:@"group.com.xxx.AppGroupsDemo"];
完整的範例在此。
xCode debug 的時候常常會丟出一些不是人看的 exception 資訊，往往找到問題點時已花費不少時間，這裡提供兩個小技巧解決這個問題。
void uncaughtExceptionHandler(NSException *exception) {
NSLog(@"CRASH: %@", exception);
NSLog(@"Stack Trace: %@", [exception callStackSymbols]);
// Internal error reporting
}
- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
NSSetUncaughtExceptionHandler(&uncaughtExceptionHandler);
// ...
}
在 xCode 裡可以直接加入 exception breakpoint 更方便。
command + 7 -> Add Exception Breakpoint
MPMoviePlayerController: 全螢幕或 inline 的方式播放(也可客製化)
MPMoviePlayerViewController: 單純全螢幕播放
UIAppearance
Dynamic Type
Accessibility
Localization
Where might you use them?
// presents
[UIView animateWithDuration:kTRANSITION_DURATION
delay:0
usingSpringWithDamping:0.75
initialSpringVelocity:10
options:0
animations:^{ ... }];
// dismiss
[UIView animateWithDuration:kTRANSITION_DURATION - 0.1
delay:0
usingSpringWithDamping:1
initialSpringVelocity:0
options:0
animations:^{ ... }];
Rendering Pipeline
Commit Transaction
drawViewHierarchyInRect:afterScreenUpdates:
New API for creating visual effects
Two effect types
UIBlurEffect - Three styles
UIVibrancyEffect
Path
bezierPath = [UIBezierPath bezierPath];
[bezierPath moveToPoint:CGPointMake(0,220)];
[bezierPath addCurveToPoint:CGPointMake(160, 115)
controlPoint:CGPointMake(0,220)
controlPoint:CGPointMake(15,100)];
...
[shapeLayer setPath:bezierPath.CGPath];
Line
Stroke
CAShapeLayer 是用 CPU 運算，再丟給 render server
當有複雜圖形時，將會花費大量的 CPU time。
+ (Class)layerClass {
return [CAShapeLayer class];
}
- (void)awakeFromNib {
CAShapeLayer *layer = (CAShapeLayer *)self.layer;
CGPathRef path = CGPathCreateWithRect(self.bounds, NULL);
[layer setPath:path];
[layer setLineWidth:6];
...
}
CAAction Protocol
- (void)runActionForKey:(NSString *)key object:(id)anObject arguments:(NSDictionary *)dict {
...
}
CALayerDelegate method
- (id<CAAction>)actionForLayer:(CALayer *)layer forKey:(NSString *)event {
if ([event isEqualToString:@"opacity"]) {
return [[APPLOpacityAction alloc] init];
}
return [super actionForLayer:layer forKey:event];
}
String to Integer
Optional Type
var optionalNumber:Int?
// default initialized to nil
optionalNumber = 6
Non-Optional Types can't be nil
var myString:String = nil
// error
func findIndexOfString(string:String, array:String[]) -> Int? {
for (index, value) in enumerate(array) {
if value == string {
return index
}
}
return nil
}
Test and unwrap at the same time
var neighbors = ["Alex", "Anna", "Madison", "Dave"]
let index = findIndexOfString("Anna", neighbors)
//if let indexValue = index { // index is of type Int, not nil?, indexValue is of type Int
if let indexValue = findIndexOfString("Anna", neighbors) { // index is of type Int, not nil?, indexValue is of type Int
println("Hello, \(neighbors[indexValue])")
}
else {
println("Must've moved away")
}
if let addressNumber = paul.residence?.address?.buildingNumber?.toInt() {
addToDatabase("Paul", addressNumber)
}
if let optional binding to test and unwrap at the same timeAutomatic Reference Counting
Weak References are optional values
Binding the optional produces a strong reference
if let tenant = apt.tenant {
tenant.buzzIn()
}
apt.tenant?.buzzIn()
Strong, Weak, and Unowned References
strong references are default
Every value must be initialized before it is used.
class RaceCar:Car {
var hasTurbo:Bool
init(color:Color, turbo:Bool) {
hasTurbo = turbo
super.init(color:color)
}
// 多個 initializers
convenience init(color:Color) {
self.init(color:color, turbo:true)
}
convenience init() {
self.init(color:Color(gray:0.4))
}
}
class FormulaOne:RaceCar {
let minimumWeight = 642
init(Color:Color) {
self.init(color:color, turbo:false)
}
}
@lazy var multiplayerManager = MultiplayerManager()
class FileHandle {
let fileDescriptor:FileDescriptor
init(path:String) {
fileDescriptior = openFile(path)
}
deinit {
closeFile(fileDescriptor)
}
}
Initialize all values before you use them
set all stored properties first, then call super.init
Designated initializers only delegate up
Convenience initializers only delegate across
Deinitializers are there... if youe need them
var clients = ["Pestov", "Buenaventura", "Sreeram", "Babbage"]
clients.sort({(a:String, b:String) -> Bool in
return a < b
})
println(clients)
用 Type Inference 簡化成
struct Array<String> {
func sort(order:(String, String) -> Bool)
}
clients.sort({a, b in a < b})
clients.sort({ $0 < $1 })
client.sort { $0 < $1 }
println(words.filter { $0.hasSuffix("gry") })
// angry
// hungry
println(words.filter { $0.hasSuffix("gry") }
.map { $0.uppercaseString })
// ANGRY
// HUNGRY
numbers.map {
// sum += $0
println($0)
}
// 可以簡化成
numbers.map(println)
var indexes = NSMutableIndexSet()
numbers.map {
indexes.addIndex($0)
}
// 可以簡化成
numbers.map(indexes.addIndex)
class TempNotifier {
var onChange:(Int) -> Void = {}
var currentTemp = 72
init() {
onChange = {[unowned self] temp in
self.currentTemp = temp
}
}
}
func stateFromPlist(list:Dictionary<String, AnyObject>) -> State?
// 正常狀況
stateFromPlist("name": "California"
"population", 38_040_000,
"abbr": "CA")
// 當傳入錯誤的型別
// ie: population 應該要傳入數字，卻傳入字串，需要回傳 nil
stateFromPlist("name": "California"
"population", "hella peeps",
"abbr": "CA")
可以用這樣的方式檢查
func stateFromPlist(list:Dictionary<String, AnyObject>) -> State? {
var name:NSString?
switch list["name"] {
case .Some(let listName as NSString):
name = listName
// ...
default:
name = nil
}
return name
}
有更好的方法
func stateFromPlist(list:Dictionary<String, AnyObject>) -> State? {
switch (list["name"], list["population"], list["abbr"]) {
case (.Some(let listName as NSString),
.Some(let pop as NSNumber),
.Some(let abbr as NSString))
where abbr.length ==2:
// 用 where 檢查 abbr 長度是否為2
return State(name:listName, population:pop, abbr:abbr)
default:
return nil
}
}
官網上寫這樣裝
curl -sk https://cloud.github.com/downloads/square/PonyDebugger/bootstrap-ponyd.py | python - --ponyd-symlink=/usr/local/bin/ponyd ~/Library/PonyDebugger
但實際在 OSX 10.9.4 上安裝卻會有問題，稍微改一下
curl -s https://cloud.github.com/downloads/square/PonyDebugger/bootstrap-ponyd.py | python - --ponyd-symlink=/usr/local/bin/ponyd ~/Library/PonyDebugger
source ~/Library/PonyDebugger/bin/activate
pip install -U -e git+https://github.com/square/PonyDebugger.git#egg=ponydebugger --allow-external pybonjour --allow-unverified pybonjour
ponyd update-devtools
接下來直接從 CocoaPods 安裝 PonyDebugger
程式中加上:
#import <PonyDebugger/PonyDebugger.h>
PDDebugger *debugger = [PDDebugger defaultInstance];
[debugger connectToURL:[NSURL URLWithString:@"ws://localhost:9000/device"]];
[debugger enableNetworkTrafficDebugging];
[debugger forwardAllNetworkTraffic];
ponyd 跑起來後，就可以用 browser 開啟 http://localhost:9000/ 進行除錯。
./ponyd serve --listen-interface=127.0.0.1
iOS8 下存取 UITableViewHeaderFooterView 在某些情況下會 crash...
只好先用下面的方式修正..
if([view isKindOfClass:[UITableViewHeaderFooterView class]]) {
UITableViewHeaderFooterView *headerView = (UITableViewHeaderFooterView *) view;
...
}
