RxSwift exit from observable chain if text is empty
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0
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I'm having trouble understanding the way to early exit from an observable sequence if I don't have the necessary info. Here's a simplified example...
@IBOutlet weak var myTextField: UITextField!
...
myButton.rx.tap. // stop here if textField is nil or empty
.flatMap { API.fetchMyList() }
.subscribe...
swift rx-swift
asked Nov 20 at 3:06
natecraft1
1,09242543
add a comment |
up vote
0
down vote
favorite
I'm having trouble understanding the way to early exit from an observable sequence if I don't have the necessary info. Here's a simplified example...
@IBOutlet weak var myTextField: UITextField!
...
myButton.rx.tap. // stop here if textField is nil or empty
.flatMap { API.fetchMyList() }
.subscribe...
swift rx-swift
asked Nov 20 at 3:06
natecraft1
1,09242543
Can you instead keep the button disabled unless there's at least one (presumably non-whitespace) character in the text field?
– NRitH
Nov 20 at 3:36
add a comment |
up vote
0
down vote
favorite
up vote
0
down vote
favorite
I'm having trouble understanding the way to early exit from an observable sequence if I don't have the necessary info. Here's a simplified example...
@IBOutlet weak var myTextField: UITextField!
...
myButton.rx.tap. // stop here if textField is nil or empty
.flatMap { API.fetchMyList() }
.subscribe...
swift rx-swift
asked Nov 20 at 3:06
natecraft1
1,09242543
I'm having trouble understanding the way to early exit from an observable sequence if I don't have the necessary info. Here's a simplified example...
@IBOutlet weak var myTextField: UITextField!
...
myButton.rx.tap. // stop here if textField is nil or empty
.flatMap { API.fetchMyList() }
.subscribe...
swift rx-swift
swift rx-swift
asked Nov 20 at 3:06
natecraft1
1,09242543
asked Nov 20 at 3:06
natecraft1
1,09242543
edited Nov 20 at 3:22
asked Nov 20 at 3:06
natecraft1
1,09242543
asked Nov 20 at 3:06
natecraft1
1,09242543
asked Nov 20 at 3:06
natecraft1
1,09242543
1,09242543
Can you instead keep the button disabled unless there's at least one (presumably non-whitespace) character in the text field?
– NRitH
Nov 20 at 3:36
add a comment |
Can you instead keep the button disabled unless there's at least one (presumably non-whitespace) character in the text field?
– NRitH
Nov 20 at 3:36
Can you instead keep the button disabled unless there's at least one (presumably non-whitespace) character in the text field?
– NRitH
Nov 20 at 3:36
Can you instead keep the button disabled unless there's at least one (presumably non-whitespace) character in the text field?
– NRitH
Nov 20 at 3:36
add a comment |
1 Answer
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up vote
1
down vote
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You’ll want to transform your observable chain to include the content of the text field, and then filter out the values you are not interested in. The operator withLatestFrom will pull values from another observable into the current chain.
@IBOutlet weak var myTextField: UITextField!
myButton.rx.tap
.withLatestFrom(myTextField.rx.text)
.filter { $0 != nil && $0?.isEmpty == false }
.flatMapLatest { // here $0 is the value of the text field
API.fetchMyList($0)
}
.subscribe...
As a side note, you’ll probably want to use flatMapLatest in lieu of flatMap, so that old requests get canceled if another tap of button occurs.
edited Nov 20 at 20:25
natecraft1
1,09242543
answered Nov 20 at 8:32
tomahh
9,48522858
add a comment |
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1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
1
down vote
accepted
You’ll want to transform your observable chain to include the content of the text field, and then filter out the values you are not interested in. The operator withLatestFrom will pull values from another observable into the current chain.
@IBOutlet weak var myTextField: UITextField!
myButton.rx.tap
.withLatestFrom(myTextField.rx.text)
.filter { $0 != nil && $0?.isEmpty == false }
.flatMapLatest { // here $0 is the value of the text field
API.fetchMyList($0)
}
.subscribe...
As a side note, you’ll probably want to use flatMapLatest in lieu of flatMap, so that old requests get canceled if another tap of button occurs.
edited Nov 20 at 20:25
natecraft1
1,09242543
answered Nov 20 at 8:32
tomahh
9,48522858
add a comment |
up vote
1
down vote
accepted
You’ll want to transform your observable chain to include the content of the text field, and then filter out the values you are not interested in. The operator withLatestFrom will pull values from another observable into the current chain.
@IBOutlet weak var myTextField: UITextField!
myButton.rx.tap
.withLatestFrom(myTextField.rx.text)
.filter { $0 != nil && $0?.isEmpty == false }
.flatMapLatest { // here $0 is the value of the text field
API.fetchMyList($0)
}
.subscribe...
As a side note, you’ll probably want to use flatMapLatest in lieu of flatMap, so that old requests get canceled if another tap of button occurs.
edited Nov 20 at 20:25
natecraft1
1,09242543
answered Nov 20 at 8:32
tomahh
9,48522858
add a comment |
up vote
1
down vote
accepted
up vote
1
down vote
accepted
You’ll want to transform your observable chain to include the content of the text field, and then filter out the values you are not interested in. The operator withLatestFrom will pull values from another observable into the current chain.
@IBOutlet weak var myTextField: UITextField!
myButton.rx.tap
.withLatestFrom(myTextField.rx.text)
.filter { $0 != nil && $0?.isEmpty == false }
.flatMapLatest { // here $0 is the value of the text field
API.fetchMyList($0)
}
.subscribe...
As a side note, you’ll probably want to use flatMapLatest in lieu of flatMap, so that old requests get canceled if another tap of button occurs.
edited Nov 20 at 20:25
natecraft1
1,09242543
answered Nov 20 at 8:32
tomahh
9,48522858
You’ll want to transform your observable chain to include the content of the text field, and then filter out the values you are not interested in. The operator withLatestFrom will pull values from another observable into the current chain.
@IBOutlet weak var myTextField: UITextField!
myButton.rx.tap
.withLatestFrom(myTextField.rx.text)
.filter { $0 != nil && $0?.isEmpty == false }
.flatMapLatest { // here $0 is the value of the text field
API.fetchMyList($0)
}
.subscribe...
As a side note, you’ll probably want to use flatMapLatest in lieu of flatMap, so that old requests get canceled if another tap of button occurs.
edited Nov 20 at 20:25
natecraft1
1,09242543
answered Nov 20 at 8:32
tomahh
9,48522858
edited Nov 20 at 20:25
natecraft1
1,09242543
edited Nov 20 at 20:25
natecraft1
1,09242543
edited Nov 20 at 20:25
natecraft1
1,09242543
1,09242543
answered Nov 20 at 8:32
tomahh
9,48522858
answered Nov 20 at 8:32
tomahh
9,48522858
answered Nov 20 at 8:32
tomahh
9,48522858
9,48522858
add a comment |
add a comment |
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Can you instead keep the button disabled unless there's at least one (presumably non-whitespace) character in the text field?
– NRitH
Nov 20 at 3:36