statemachine

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State Machine

Abstract implementation to handle view states changes based on some key (represented by a Int)

Usage

Add into your project

Module -> build.gradle

implementation "io.github.matheus-corregiari:statemachine:$latest_version"

or

api "io.github.matheus-corregiari:statemachine:$latest_version"

How to use

Setup

Kotlin

stateMachine.setup {
    config { ... } // Optional configuration for initial setup

    state(YOUR_INT_CONSTANT) { // to Add a state into the state machine
        onEnter { ... }   // Will be executed when this state becomes Active

        ...

        onExit { ... }    // Will be executed when this state is leaving
    }
}

Java

final Config config = stateMachine.getConfig();

...

final State state = stateMachine.newStateInstance();
state.onEnter(() -> {}); // Will be executed when this state becomes Active

...

state.onExit(() -> {});  // Will be executed when this state is leaving

stateMachine
    .addState(YOUR_INT_CONSTANT, state) // Add the configured state
    .restoreInstanceState(bundle);      // Optional restore state
    .start();                           // In java you need to start the machine after the setup

Change State

// Simple change state
stateMachine.changeState(YOUR_INT_CONSTANT);

// To force the state change even when it is the current state
stateMachine.changeState(YOUR_INT_CONSTANT, true);

// A custom onChangeState implementation [See the Config section]
stateMachine.changeState(YOUR_INT_CONSTANT, stateKey -> { ... });

// Full
stateMachine.changeState(YOUR_INT_CONSTANT, true, stateKey -> { ... });

Save and Restore State

Save

outState.putBundle("YOUR_STATE_KEY", stateMachine.saveInstanceState())

Restore

stateMachine.restoreInstanceState(savedInstanceState.getBundle("YOUR_STATE_KEY"))

Config

Kotlin

stateMachine.config {
    initialState = INITIAL_STATE_KEY
    setOnChangeState { stateKey -> ... } // Handler called whenever state becomes active
}

Java

final Config config = stateMachine.getConfig();

config.setInitialState(INITIAL_STATE_KEY);
config.setOnChangeState(stateKey -> { ... }); // Handler called whenever state becomes active

ViewStateMachine

Implementation based on visibility changes on views. To use this, all views must be already in the layout.

Simple Usage

Kotlin

stateMachine.state(YOUR_INT_CONSTANT) {

    // Visibility
    visibles()   // views to become visible
    invisibles() // views to become invisible
    gones()      // views to become gone

    // Enable
    enables()    // views to become enable
    disables()   // views to become disable

}

Java

final State state = stateMachine.newStateInstance();

state
    // Visibility
    .visibles()   // views to become visible
    .invisibles() // views to become invisible
    .gones()      // views to become gone

    // Enable
    .enables()    // views to become enable
    .disables();  // views to become disable

stateMachine.addState(YOUR_INT_CONSTANT, state);

SceneStateMachine

Implementation based on Transition Scenes framework to change a layout content. To use this, you must have a layout container to put a custom layout on it.

Usage

Kotlin

stateMachine.state(YOUR_INT_CONSTANT) {

    scene(layoutRes to containerView) // Receives a Pair with LayoutId and the container ViewGroup to inflate the layout on it
    transition()                      // Optional Transition to animate the scene change

}

Java

final State state = stateMachine.newStateInstance();

state
    .scene(layoutRes to containerView) // Receives a Pair with LayoutId and the container ViewGroup to inflate the layout on it
    .transition();                     // Optional Transition to animate the scene change

stateMachine.addState(YOUR_INT_CONSTANT, state);

AVOID CRASHES AND LEAKS

If your Statemachine instance persists configuration changes, or view lifecycle. Don't forget to call the 'shutdown' method

stateMachine.shutdown()

This will erase all current references and states of the machine. =)

PROGUARD RULES

If you are not using Kotlin(and you should), you need to add this into your proguard-rules.pro file. Because if you are not using Kotlin, the shrinker will become angry with you, telling that some classes cannot be found.

# State Machine (only if you don't use Kotlin)
-dontwarn kotlin.jvm.internal.Intrinsics
-dontwarn kotlin.Pair
-dontwarn kotlin.Metadata
-dontwarn kotlin.jvm.functions.Function1
-dontwarn kotlin.Unit