How to trigger block from any of multiple signal producers?

Question

How do I trigger one block of code whenever any of a set of SignalProducers change? In other words, how do I get rid of my current redundant code:

property1.producer.startWithValues { (value) in 
    // do stuff with property1.value and property2.value
}

property2.producer.startWithValues { (value) in 
    // do the same stuff with property1.value and property2.value
}

Can you add a bit of context? For example, does the code block use both properties' values or only the value that gets a passed in to the closure? — jjoelson, Sep 22 '17 at 20:37
Sorry, the block uses both property's values. I've modified the above to clarify. — ozool, Sep 23 '17 at 03:06

score 0 · Answer 1 · answered Sep 22 '17 at 20:55

0

You can save the block of code as a variable, then you would simply assign that variable to property1.producer.startWithValues.

answered Sep 22 '17 at 20:55

esreli

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You mean save the block as a variable, and then use it in both places? It seems like there should be a way to have a single block run when either property changes.. Some way to say "if either property changes, run this block"... – ozool Sep 23 '17 at 03:07

score 0 · Accepted Answer · answered Sep 23 '17 at 03:18

You can use combineLatest to create a new property that contains both values:

let prop = property1.combineLatest(with: property2)
prop.producer.startWithValues { (val1, val2) in
    // do stuff here
}

If either value changes, the block will be triggered.

How to trigger block from any of multiple signal producers?

2 Answers2

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