Mixing
RxSwift exit from observable chain if text is empty
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 '18 at 3:06
natecraft1natecraft1
1,09242643
add a comment |
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 '18 at 3:06
natecraft1natecraft1
1,09242643
Can you instead keep the button disabled unless there's at least one (presumably non-whitespace) character in the text field?
– NRitH
Nov 20 '18 at 3:36
add a comment |
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 '18 at 3:06
natecraft1natecraft1
1,09242643
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 '18 at 3:06
natecraft1natecraft1
1,09242643
asked Nov 20 '18 at 3:06
natecraft1natecraft1
1,09242643
edited Nov 20 '18 at 3:22
natecraft1
asked Nov 20 '18 at 3:06
natecraft1natecraft1
1,09242643
asked Nov 20 '18 at 3:06
natecraft1natecraft1
1,09242643
asked Nov 20 '18 at 3:06
natecraft1natecraft1
1,09242643
1,09242643
Can you instead keep the button disabled unless there's at least one (presumably non-whitespace) character in the text field?
– NRitH
Nov 20 '18 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 '18 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 '18 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 '18 at 3:36
add a comment |
1 Answer
1
active
oldest
votes
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 '18 at 20:25
natecraft1
1,09242643
answered Nov 20 '18 at 8:32
tomahhtomahh
9,54922858
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
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 '18 at 20:25
natecraft1
1,09242643
answered Nov 20 '18 at 8:32
tomahhtomahh
9,54922858
add a comment |
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 '18 at 20:25
natecraft1
1,09242643
answered Nov 20 '18 at 8:32
tomahhtomahh
9,54922858
add a comment |
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 '18 at 20:25
natecraft1
1,09242643
answered Nov 20 '18 at 8:32
tomahhtomahh
9,54922858
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 '18 at 20:25
natecraft1
1,09242643
answered Nov 20 '18 at 8:32
tomahhtomahh
9,54922858
edited Nov 20 '18 at 20:25
natecraft1
1,09242643
edited Nov 20 '18 at 20:25
natecraft1
1,09242643
edited Nov 20 '18 at 20:25
natecraft1
1,09242643
1,09242643
answered Nov 20 '18 at 8:32
tomahhtomahh
9,54922858
answered Nov 20 '18 at 8:32
tomahhtomahh
9,54922858
answered Nov 20 '18 at 8:32
tomahhtomahh
9,54922858
9,54922858
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 '18 at 3:36