Hello Workflow

A brief introduction to https://github.com/square/workflow/, presented to https://www.meetup.com/GDGSanFrancisco.

Original deck: https://docs.google.com/presentation/d/1-LLSFlGcD0fMaVbCn75Q4hgK6_E-YaAv0aI3OcQEHi0/edit#slide=id.g4088c7565d_2_5

Live code source: https://github.com/square/workflow/pull/413

Transcript

1. Ray Ryan Zach Klippenstein Hello Square Workflow
2. Nav logic sprawl Tragedy of convenient presenters
3. CartScreen ChargeScreen TipScreen SignatureScreen ReceiptScreen
4. class ChargeScreen { fun onCardSwiped(card: Card) { doStuffWithCard(card) if (tippingEnabled) goTo(TipScreen) else if (signatureRequired) goTo(SignatureScreen) else if (!skipReceipts) goTo(ReceiptScreen) else popTo(CartScreen) } } class TipScreen { fun onTip(tip: Money) { doStuffWithTip(tip) if (signatureRequired) goTo(SignatureScreen) else if (!skipReceipts) goTo(ReceiptScreen) else popTo(CartScreen) } }
5. class ChargeScreen { fun onCardSwiped(card: Card) { doStuffWithCard(card) if (tippingEnabled) goTo(TipScreen) else if (signatureRequired) goTo(SignatureScreen) else if (!skipReceipts) goTo(ReceiptScreen) else popTo(CartScreen) } } class TipScreen { fun onTip(tip: Money) { doStuffWithTip(tip) if (signatureRequired) goTo(SignatureScreen) else if (!skipReceipts) goTo(ReceiptScreen) else popTo(CartScreen) } }
6. CartScreen ChargeScreen TipScreen SignatureScreen ReceiptScreen
7. class CheckoutWorkflow { } CartScreen ChargeScreen TipScreen SignatureScreen ReceiptScreen onCard / tipping onCard onTip onCard / skipSig onTip / skipSig onSig onSig / skipReceipt onReceipt
8. Those who do not know React are condemned to reinvent it poorly.
9. Workflow moving parts
10. Workflow
11. class NewGameScreen( val onStart: (String, String) -> Unit ) Rendering Workflow
12. class NewGameScreen( val onStart: (String, String) -> Unit ) class NewGameRunner( view: View ) : LayoutRunner<NewGameScreen> { val player1 = view.findById<TextView>() // etc. fun showRendering(r: NewGameScreen) { playButton.setOnClickHandler { r.onStart(player1.text, player2.text) } } } LayoutRunner Workflow Rendering
13. class NewGameScreen( val onStart: (String, String) -> Unit ) class NewGameRunner( view: View ) : LayoutRunner<NewGameScreen> { val player1 = view.findById<TextView>() // etc. fun showRendering(r: NewGameScreen) { playButton.setOnClickHandler { r.onStart(player1.text, player2.text) } } } LayoutRunner Workflow Rendering
14. Let’s code! https://github.com/square/workflow/tree/zachklipp+ray/todo-android-livecode
15. square.com