Mixing
Syntax of Block in Swift
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I am trying to rewrite from Objective-C to Swift, I cannot work out the syntax or understand the docs
Here is a simplified example in Objective-C I wrote:
[UIView animateWithDuration:10.0 animations:^{self.navigationController.toolbar.frame = CGRectMake(0,10,0,10);}];
How do I write this in Swift?
This is the template autocomplete gives:
UIView.animateWithDuration(duration: NSTimeInterval, animations: (() -> Void))
ios swift swift3
edited Jan 3 at 8:08
Martijn Pieters♦
726k14325482349
asked Jun 4 '14 at 13:25
Ryan HeitnerRyan Heitner
8,43155691
add a comment |
I am trying to rewrite from Objective-C to Swift, I cannot work out the syntax or understand the docs
Here is a simplified example in Objective-C I wrote:
[UIView animateWithDuration:10.0 animations:^{self.navigationController.toolbar.frame = CGRectMake(0,10,0,10);}];
How do I write this in Swift?
This is the template autocomplete gives:
UIView.animateWithDuration(duration: NSTimeInterval, animations: (() -> Void))
ios swift swift3
edited Jan 3 at 8:08
Martijn Pieters♦
726k14325482349
asked Jun 4 '14 at 13:25
Ryan HeitnerRyan Heitner
8,43155691
add a comment |
I am trying to rewrite from Objective-C to Swift, I cannot work out the syntax or understand the docs
Here is a simplified example in Objective-C I wrote:
[UIView animateWithDuration:10.0 animations:^{self.navigationController.toolbar.frame = CGRectMake(0,10,0,10);}];
How do I write this in Swift?
This is the template autocomplete gives:
UIView.animateWithDuration(duration: NSTimeInterval, animations: (() -> Void))
ios swift swift3
edited Jan 3 at 8:08
Martijn Pieters♦
726k14325482349
asked Jun 4 '14 at 13:25
Ryan HeitnerRyan Heitner
8,43155691
I am trying to rewrite from Objective-C to Swift, I cannot work out the syntax or understand the docs
Here is a simplified example in Objective-C I wrote:
[UIView animateWithDuration:10.0 animations:^{self.navigationController.toolbar.frame = CGRectMake(0,10,0,10);}];
How do I write this in Swift?
This is the template autocomplete gives:
UIView.animateWithDuration(duration: NSTimeInterval, animations: (() -> Void))
ios swift swift3
ios swift swift3
edited Jan 3 at 8:08
Martijn Pieters♦
726k14325482349
asked Jun 4 '14 at 13:25
Ryan HeitnerRyan Heitner
8,43155691
edited Jan 3 at 8:08
Martijn Pieters♦
726k14325482349
asked Jun 4 '14 at 13:25
Ryan HeitnerRyan Heitner
8,43155691
edited Jan 3 at 8:08
Martijn Pieters♦
726k14325482349
edited Jan 3 at 8:08
Martijn Pieters♦
726k14325482349
edited Jan 3 at 8:08
Martijn Pieters♦
726k14325482349
726k14325482349
asked Jun 4 '14 at 13:25
Ryan HeitnerRyan Heitner
8,43155691
asked Jun 4 '14 at 13:25
Ryan HeitnerRyan Heitner
8,43155691
asked Jun 4 '14 at 13:25
Ryan HeitnerRyan Heitner
8,43155691
8,43155691
add a comment |
add a comment |
4 Answers
4
active
oldest
votes
Since the expected argument types and return type to the animations argument are known the compiler can infer them without a problem. This should work (though I don't have the playground available right at the moment:
UIView.animateWithDuration(10.0, animations: {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
})
for more info about closures see the chapter in the swift docs
note about CGRect() - the developer docs show CGRect() being used in swift code. Perhaps it requires an import?
update for comments: you can also use a trailing closure like so:
UIView.animateWithDuration(10.0) {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
}
edited Jun 4 '14 at 13:45
Gabriele Petronella
92.3k18181213
answered Jun 4 '14 at 13:28
JiaaroJiaaro
46.3k32135171
1
maybe a trailing closure would be even simpler? :)
– Sulthan
Jun 4 '14 at 13:29
2
@Jiaaro Named arguments are not a problem. It must be the last argument, that's all.
– Sulthan
Jun 4 '14 at 13:34
Is it just me or is trailing closures much more confusing? Does anyone know what language this was influenced by or why this makes sense?
– sanz
Jun 4 '14 at 14:24
Is this to allow for curry operations? Seems like a obtuse way to do it...
– sanz
Jun 4 '14 at 14:28
It allows callbacks to "read like control flow"
– Jiaaro
Jun 4 '14 at 14:39
|
show 1 more comment
This is the swift closure format:
{(parameter:type, parameter: type, ...) -> returntype in
//do stuff
}
This is what you should do:
//The animation closure will take no parameters and return void (nothing).
UIView.animateWithDuration(duration: NSTimeInterval, animations: {() -> Void in
//Animate anything.
})
Here is the documentation for closures.
edited Jun 6 '15 at 20:01
luk2302
34.5k1773101
answered Jun 4 '14 at 13:27
67cherries67cherries
5,37763049
add a comment |
Following code can guide to write your own block.
class func testFunc(completion: ((list : NSArray!) -> Void)?) {
//--- block code.
if completion! != nil {
completion! (list: NSArray())
}
}
and you can call it like -
className.testFunc {
(list: NSArray!) -> Void in
}
answered Sep 30 '14 at 11:56
Prakash RajPrakash Raj
1,88611213
add a comment |
You can basically write it in 3 identical ways:
write what to do right in the closure/code block:
UIView.animateWithDuration(10.0) {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
}
This is also known as trailing closure ( You can only do trailing closure if the closure parameter is the last parameter)
This doesn't mean the parameter 'animations' is no longer written. It is written but just as in the format of above.
Write exactly within the lines, most developers avoid such, because it's a little buggy to write with all the parenthesis and braces.
UIView.animateWithDuration(10.0, animations: {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
})
(Contrary to trailing closure you wrote name ie 'animations')
This is known as inline closure
Write in a more modular sense
UIView.animateWithDuration(duration: NSTimeInterval, animations: animatingFunc)
func animatingFunc() {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
}
Remember the type of the parameter 'animations' was () -> Void
Exactly as what we are doing, animatingFunc takes no parameters ie '()' and returns nothing ie 'void'
(In Swift, functions are types and can be passed in as parameters)
Some might say this is more readable some might say trailing closure is...
Side note1
You can also do nothing ( which really doesn't make sense but in many other handlers/animations/completion handlers you may not want to do anything)
UIView.animateWithDuration(duration: NSTimeInterval, animations: nil)
Side note2
Closures becomes more interesting when you have to capture a value. See this simple demonstration.
For more information about Swift closures see Apple's Documentation
edited Jun 26 '18 at 21:15
David
2,3492742
answered Dec 1 '16 at 22:41
HoneyHoney
10.5k662124
add a comment |
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4 Answers
4
active
oldest
votes
4 Answers
4
active
oldest
votes
active
oldest
votes
active
oldest
votes
Since the expected argument types and return type to the animations argument are known the compiler can infer them without a problem. This should work (though I don't have the playground available right at the moment:
UIView.animateWithDuration(10.0, animations: {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
})
for more info about closures see the chapter in the swift docs
note about CGRect() - the developer docs show CGRect() being used in swift code. Perhaps it requires an import?
update for comments: you can also use a trailing closure like so:
UIView.animateWithDuration(10.0) {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
}
edited Jun 4 '14 at 13:45
Gabriele Petronella
92.3k18181213
answered Jun 4 '14 at 13:28
JiaaroJiaaro
46.3k32135171
1
maybe a trailing closure would be even simpler? :)
– Sulthan
Jun 4 '14 at 13:29
2
@Jiaaro Named arguments are not a problem. It must be the last argument, that's all.
– Sulthan
Jun 4 '14 at 13:34
Is it just me or is trailing closures much more confusing? Does anyone know what language this was influenced by or why this makes sense?
– sanz
Jun 4 '14 at 14:24
Is this to allow for curry operations? Seems like a obtuse way to do it...
– sanz
Jun 4 '14 at 14:28
It allows callbacks to "read like control flow"
– Jiaaro
Jun 4 '14 at 14:39
|
show 1 more comment
Since the expected argument types and return type to the animations argument are known the compiler can infer them without a problem. This should work (though I don't have the playground available right at the moment:
UIView.animateWithDuration(10.0, animations: {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
})
for more info about closures see the chapter in the swift docs
note about CGRect() - the developer docs show CGRect() being used in swift code. Perhaps it requires an import?
update for comments: you can also use a trailing closure like so:
UIView.animateWithDuration(10.0) {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
}
edited Jun 4 '14 at 13:45
Gabriele Petronella
92.3k18181213
answered Jun 4 '14 at 13:28
JiaaroJiaaro
46.3k32135171
1
maybe a trailing closure would be even simpler? :)
– Sulthan
Jun 4 '14 at 13:29
2
@Jiaaro Named arguments are not a problem. It must be the last argument, that's all.
– Sulthan
Jun 4 '14 at 13:34
Is it just me or is trailing closures much more confusing? Does anyone know what language this was influenced by or why this makes sense?
– sanz
Jun 4 '14 at 14:24
Is this to allow for curry operations? Seems like a obtuse way to do it...
– sanz
Jun 4 '14 at 14:28
It allows callbacks to "read like control flow"
– Jiaaro
Jun 4 '14 at 14:39
|
show 1 more comment
Since the expected argument types and return type to the animations argument are known the compiler can infer them without a problem. This should work (though I don't have the playground available right at the moment:
UIView.animateWithDuration(10.0, animations: {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
})
for more info about closures see the chapter in the swift docs
note about CGRect() - the developer docs show CGRect() being used in swift code. Perhaps it requires an import?
update for comments: you can also use a trailing closure like so:
UIView.animateWithDuration(10.0) {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
}
edited Jun 4 '14 at 13:45
Gabriele Petronella
92.3k18181213
answered Jun 4 '14 at 13:28
JiaaroJiaaro
46.3k32135171
Since the expected argument types and return type to the animations argument are known the compiler can infer them without a problem. This should work (though I don't have the playground available right at the moment:
UIView.animateWithDuration(10.0, animations: {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
})
for more info about closures see the chapter in the swift docs
note about CGRect() - the developer docs show CGRect() being used in swift code. Perhaps it requires an import?
update for comments: you can also use a trailing closure like so:
UIView.animateWithDuration(10.0) {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
}
edited Jun 4 '14 at 13:45
Gabriele Petronella
92.3k18181213
answered Jun 4 '14 at 13:28
JiaaroJiaaro
46.3k32135171
edited Jun 4 '14 at 13:45
Gabriele Petronella
92.3k18181213
edited Jun 4 '14 at 13:45
Gabriele Petronella
92.3k18181213
edited Jun 4 '14 at 13:45
Gabriele Petronella
92.3k18181213
92.3k18181213
answered Jun 4 '14 at 13:28
JiaaroJiaaro
46.3k32135171
answered Jun 4 '14 at 13:28
JiaaroJiaaro
46.3k32135171
answered Jun 4 '14 at 13:28
JiaaroJiaaro
46.3k32135171
46.3k32135171
1
maybe a trailing closure would be even simpler? :)
– Sulthan
Jun 4 '14 at 13:29
2
@Jiaaro Named arguments are not a problem. It must be the last argument, that's all.
– Sulthan
Jun 4 '14 at 13:34
Is it just me or is trailing closures much more confusing? Does anyone know what language this was influenced by or why this makes sense?
– sanz
Jun 4 '14 at 14:24
Is this to allow for curry operations? Seems like a obtuse way to do it...
– sanz
Jun 4 '14 at 14:28
It allows callbacks to "read like control flow"
– Jiaaro
Jun 4 '14 at 14:39
|
show 1 more comment
1
maybe a trailing closure would be even simpler? :)
– Sulthan
Jun 4 '14 at 13:29
2
@Jiaaro Named arguments are not a problem. It must be the last argument, that's all.
– Sulthan
Jun 4 '14 at 13:34
Is it just me or is trailing closures much more confusing? Does anyone know what language this was influenced by or why this makes sense?
– sanz
Jun 4 '14 at 14:24
Is this to allow for curry operations? Seems like a obtuse way to do it...
– sanz
Jun 4 '14 at 14:28
It allows callbacks to "read like control flow"
– Jiaaro
Jun 4 '14 at 14:39
1
1
maybe a trailing closure would be even simpler? :)
– Sulthan
Jun 4 '14 at 13:29
maybe a trailing closure would be even simpler? :)
– Sulthan
Jun 4 '14 at 13:29
2
2
@Jiaaro Named arguments are not a problem. It must be the last argument, that's all.
– Sulthan
Jun 4 '14 at 13:34
@Jiaaro Named arguments are not a problem. It must be the last argument, that's all.
– Sulthan
Jun 4 '14 at 13:34
Is it just me or is trailing closures much more confusing? Does anyone know what language this was influenced by or why this makes sense?
– sanz
Jun 4 '14 at 14:24
Is it just me or is trailing closures much more confusing? Does anyone know what language this was influenced by or why this makes sense?
– sanz
Jun 4 '14 at 14:24
Is this to allow for curry operations? Seems like a obtuse way to do it...
– sanz
Jun 4 '14 at 14:28
Is this to allow for curry operations? Seems like a obtuse way to do it...
– sanz
Jun 4 '14 at 14:28
It allows callbacks to "read like control flow"
– Jiaaro
Jun 4 '14 at 14:39
It allows callbacks to "read like control flow"
– Jiaaro
Jun 4 '14 at 14:39
|
show 1 more comment
This is the swift closure format:
{(parameter:type, parameter: type, ...) -> returntype in
//do stuff
}
This is what you should do:
//The animation closure will take no parameters and return void (nothing).
UIView.animateWithDuration(duration: NSTimeInterval, animations: {() -> Void in
//Animate anything.
})
Here is the documentation for closures.
edited Jun 6 '15 at 20:01
luk2302
34.5k1773101
answered Jun 4 '14 at 13:27
67cherries67cherries
5,37763049
add a comment |
This is the swift closure format:
{(parameter:type, parameter: type, ...) -> returntype in
//do stuff
}
This is what you should do:
//The animation closure will take no parameters and return void (nothing).
UIView.animateWithDuration(duration: NSTimeInterval, animations: {() -> Void in
//Animate anything.
})
Here is the documentation for closures.
edited Jun 6 '15 at 20:01
luk2302
34.5k1773101
answered Jun 4 '14 at 13:27
67cherries67cherries
5,37763049
add a comment |
This is the swift closure format:
{(parameter:type, parameter: type, ...) -> returntype in
//do stuff
}
This is what you should do:
//The animation closure will take no parameters and return void (nothing).
UIView.animateWithDuration(duration: NSTimeInterval, animations: {() -> Void in
//Animate anything.
})
Here is the documentation for closures.
edited Jun 6 '15 at 20:01
luk2302
34.5k1773101
answered Jun 4 '14 at 13:27
67cherries67cherries
5,37763049
This is the swift closure format:
{(parameter:type, parameter: type, ...) -> returntype in
//do stuff
}
This is what you should do:
//The animation closure will take no parameters and return void (nothing).
UIView.animateWithDuration(duration: NSTimeInterval, animations: {() -> Void in
//Animate anything.
})
Here is the documentation for closures.
edited Jun 6 '15 at 20:01
luk2302
34.5k1773101
answered Jun 4 '14 at 13:27
67cherries67cherries
5,37763049
edited Jun 6 '15 at 20:01
luk2302
34.5k1773101
edited Jun 6 '15 at 20:01
luk2302
34.5k1773101
edited Jun 6 '15 at 20:01
luk2302
34.5k1773101
34.5k1773101
answered Jun 4 '14 at 13:27
67cherries67cherries
5,37763049
answered Jun 4 '14 at 13:27
67cherries67cherries
5,37763049
answered Jun 4 '14 at 13:27
67cherries67cherries
5,37763049
5,37763049
add a comment |
add a comment |
Following code can guide to write your own block.
class func testFunc(completion: ((list : NSArray!) -> Void)?) {
//--- block code.
if completion! != nil {
completion! (list: NSArray())
}
}
and you can call it like -
className.testFunc {
(list: NSArray!) -> Void in
}
answered Sep 30 '14 at 11:56
Prakash RajPrakash Raj
1,88611213
add a comment |
Following code can guide to write your own block.
class func testFunc(completion: ((list : NSArray!) -> Void)?) {
//--- block code.
if completion! != nil {
completion! (list: NSArray())
}
}
and you can call it like -
className.testFunc {
(list: NSArray!) -> Void in
}
answered Sep 30 '14 at 11:56
Prakash RajPrakash Raj
1,88611213
add a comment |
Following code can guide to write your own block.
class func testFunc(completion: ((list : NSArray!) -> Void)?) {
//--- block code.
if completion! != nil {
completion! (list: NSArray())
}
}
and you can call it like -
className.testFunc {
(list: NSArray!) -> Void in
}
answered Sep 30 '14 at 11:56
Prakash RajPrakash Raj
1,88611213
Following code can guide to write your own block.
class func testFunc(completion: ((list : NSArray!) -> Void)?) {
//--- block code.
if completion! != nil {
completion! (list: NSArray())
}
}
and you can call it like -
className.testFunc {
(list: NSArray!) -> Void in
}
answered Sep 30 '14 at 11:56
Prakash RajPrakash Raj
1,88611213
answered Sep 30 '14 at 11:56
Prakash RajPrakash Raj
1,88611213
answered Sep 30 '14 at 11:56
Prakash RajPrakash Raj
1,88611213
answered Sep 30 '14 at 11:56
Prakash RajPrakash Raj
1,88611213
1,88611213
add a comment |
add a comment |
You can basically write it in 3 identical ways:
write what to do right in the closure/code block:
UIView.animateWithDuration(10.0) {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
}
This is also known as trailing closure ( You can only do trailing closure if the closure parameter is the last parameter)
This doesn't mean the parameter 'animations' is no longer written. It is written but just as in the format of above.
Write exactly within the lines, most developers avoid such, because it's a little buggy to write with all the parenthesis and braces.
UIView.animateWithDuration(10.0, animations: {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
})
(Contrary to trailing closure you wrote name ie 'animations')
This is known as inline closure
Write in a more modular sense
UIView.animateWithDuration(duration: NSTimeInterval, animations: animatingFunc)
func animatingFunc() {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
}
Remember the type of the parameter 'animations' was () -> Void
Exactly as what we are doing, animatingFunc takes no parameters ie '()' and returns nothing ie 'void'
(In Swift, functions are types and can be passed in as parameters)
Some might say this is more readable some might say trailing closure is...
Side note1
You can also do nothing ( which really doesn't make sense but in many other handlers/animations/completion handlers you may not want to do anything)
UIView.animateWithDuration(duration: NSTimeInterval, animations: nil)
Side note2
Closures becomes more interesting when you have to capture a value. See this simple demonstration.
For more information about Swift closures see Apple's Documentation
edited Jun 26 '18 at 21:15
David
2,3492742
answered Dec 1 '16 at 22:41
HoneyHoney
10.5k662124
add a comment |
You can basically write it in 3 identical ways:
write what to do right in the closure/code block:
UIView.animateWithDuration(10.0) {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
}
This is also known as trailing closure ( You can only do trailing closure if the closure parameter is the last parameter)
This doesn't mean the parameter 'animations' is no longer written. It is written but just as in the format of above.
Write exactly within the lines, most developers avoid such, because it's a little buggy to write with all the parenthesis and braces.
UIView.animateWithDuration(10.0, animations: {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
})
(Contrary to trailing closure you wrote name ie 'animations')
This is known as inline closure
Write in a more modular sense
UIView.animateWithDuration(duration: NSTimeInterval, animations: animatingFunc)
func animatingFunc() {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
}
Remember the type of the parameter 'animations' was () -> Void
Exactly as what we are doing, animatingFunc takes no parameters ie '()' and returns nothing ie 'void'
(In Swift, functions are types and can be passed in as parameters)
Some might say this is more readable some might say trailing closure is...
Side note1
You can also do nothing ( which really doesn't make sense but in many other handlers/animations/completion handlers you may not want to do anything)
UIView.animateWithDuration(duration: NSTimeInterval, animations: nil)
Side note2
Closures becomes more interesting when you have to capture a value. See this simple demonstration.
For more information about Swift closures see Apple's Documentation
edited Jun 26 '18 at 21:15
David
2,3492742
answered Dec 1 '16 at 22:41
HoneyHoney
10.5k662124
add a comment |
You can basically write it in 3 identical ways:
write what to do right in the closure/code block:
UIView.animateWithDuration(10.0) {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
}
This is also known as trailing closure ( You can only do trailing closure if the closure parameter is the last parameter)
This doesn't mean the parameter 'animations' is no longer written. It is written but just as in the format of above.
Write exactly within the lines, most developers avoid such, because it's a little buggy to write with all the parenthesis and braces.
UIView.animateWithDuration(10.0, animations: {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
})
(Contrary to trailing closure you wrote name ie 'animations')
This is known as inline closure
Write in a more modular sense
UIView.animateWithDuration(duration: NSTimeInterval, animations: animatingFunc)
func animatingFunc() {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
}
Remember the type of the parameter 'animations' was () -> Void
Exactly as what we are doing, animatingFunc takes no parameters ie '()' and returns nothing ie 'void'
(In Swift, functions are types and can be passed in as parameters)
Some might say this is more readable some might say trailing closure is...
Side note1
You can also do nothing ( which really doesn't make sense but in many other handlers/animations/completion handlers you may not want to do anything)
UIView.animateWithDuration(duration: NSTimeInterval, animations: nil)
Side note2
Closures becomes more interesting when you have to capture a value. See this simple demonstration.
For more information about Swift closures see Apple's Documentation
edited Jun 26 '18 at 21:15
David
2,3492742
answered Dec 1 '16 at 22:41
HoneyHoney
10.5k662124
You can basically write it in 3 identical ways:
write what to do right in the closure/code block:
UIView.animateWithDuration(10.0) {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
}
This is also known as trailing closure ( You can only do trailing closure if the closure parameter is the last parameter)
This doesn't mean the parameter 'animations' is no longer written. It is written but just as in the format of above.
Write exactly within the lines, most developers avoid such, because it's a little buggy to write with all the parenthesis and braces.
UIView.animateWithDuration(10.0, animations: {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
})
(Contrary to trailing closure you wrote name ie 'animations')
This is known as inline closure
Write in a more modular sense
UIView.animateWithDuration(duration: NSTimeInterval, animations: animatingFunc)
func animatingFunc() {
self.navigationController.toolbar.frame = CGRect(x:0.0, y:10.0, width:10.0, height:0.0)
}
Remember the type of the parameter 'animations' was () -> Void
Exactly as what we are doing, animatingFunc takes no parameters ie '()' and returns nothing ie 'void'
(In Swift, functions are types and can be passed in as parameters)
Some might say this is more readable some might say trailing closure is...
Side note1
You can also do nothing ( which really doesn't make sense but in many other handlers/animations/completion handlers you may not want to do anything)
UIView.animateWithDuration(duration: NSTimeInterval, animations: nil)
Side note2
Closures becomes more interesting when you have to capture a value. See this simple demonstration.
For more information about Swift closures see Apple's Documentation
edited Jun 26 '18 at 21:15
David
2,3492742
answered Dec 1 '16 at 22:41
HoneyHoney
10.5k662124
edited Jun 26 '18 at 21:15
David
2,3492742
edited Jun 26 '18 at 21:15
David
2,3492742
edited Jun 26 '18 at 21:15
David
2,3492742
2,3492742
answered Dec 1 '16 at 22:41
HoneyHoney
10.5k662124
answered Dec 1 '16 at 22:41
HoneyHoney
10.5k662124
answered Dec 1 '16 at 22:41
HoneyHoney
10.5k662124
10.5k662124
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