FlexibleHybrid

Including simplifying the interface between Webview and Native and asynchronous processing,
It is a library that provides multiple convenience features for Webview use.

How to add libraries

minSdkVersion 23
Minimum Android WebviewVersion 55

jitpack

Add the following to gradle's repositories

repositories {
    ...
    maven { url 'https://jitpack.io' }
}

Add the following dependencies in gradle

dependencies {
    implementation 'com.github.Kyun-J:FlexHybridApp-Android:latest-version'
}

Key Features

It has similar development rules and functions to the iOS version.
The interface between Webview and Native operates asynchronously.
1. Called and returned as Promise from the Web.
2. In Native, it operates as Coroutine.
You can define behavior on interface with Kotlin's lambda.
In addition to basic data types, Array, Map, Model can be used.
By setting the number of threads the interface will run on, you can parallelize multiple operations.
You can prevent Native calls from unwanted sites by designating URLs that allow interface operation.

and various other functions exist.

Basic usage of interface

Web to Nativew

Interface registration

// in kotlin
flexWebView.setInterface("funcName") { args ->
    "received from web - ${args[0]?.toString() ?: "no value"}, return to web - ${100}"
}
flexWebView.loadUrl(someUrl)

Interface invoke

// in js
const test = async (req) => {
  const res = await $flex.funcName(req);
  console.log(res); // received from web - 200, return to web - 100
};
test(200);

Natvie to Web

Interface registration

After the $flex object is loaded (the window.onFlexLoad function can be checked on the $flex Load time), register the interface.

// in js
window.onFlexLoad = () => {
  $flex.web.funcName = async (req) => {
    return await new Promise((resolve) => {
      setTimeout(() => resolve(`received from web - ${req}`), 100);
    });
  };
};

Interface invoke

// in kotlin
flexWebView.evalFlexFunc("funcName", "sendData") { response ->
    Log.i("WebToNative", response.toString()) // received from web - sendData
}

Advanced usage of interface

FlexData and FlexArguemtns

The data received from the Web is converted into a FlexData object for TypeSafe loading.
In Web to native interface, Arguments passed from Web functions are converted into FlexArguemnts objects.
FlexArguments is an Array of FlexData.

// in js
$flex.funcName("test1", 2, 3.1, true, [0, 1, 2], { test: "object" });

//in kotlin
flexWebView.setInterface("funcName") { args ->
    if (args == null) return@setInterface

    val first = args[0].asString() // "test"
    val second = args[1].asInt() // 2
    val third = args[2].asDouble() // 3.1
    val fourth = args[3].asBoolean() // true
    val fifth = args[4].asArray() // array of 0, 1, 2
    val sixth = args[5].asMap() // map of first key - test, value - "object"

    val argsArray: Array<FlexData> = args.toArray()
    val argsList: List<FlexData> = args.toList()
}

Model Class

Data to be used for the interface can be used as a Model Class.
In this case, the rules below apply.

Model Class must Inheritance FlexType class.
In Web, it is converted into object form.
Array cannot be used as a member variable of Class, and only classes that inherit Iterable (such as ArrayList) can be used when implementing a list.
When receiving Model Class as Arguments in Native, only one object corresponding to the Model in Web should be delivered.

// in kotlin
data class TestModel(
    val name: String,
    val data2: TestModel2
): FlexType

data class TestModel2(
    val testInt: Int
): FlexType

data class ArgsTestModel(
    val testModel: TestModel
): FlexType

flexWebView.setInterface("modelTest") { args ->
    TestModel("test", TestModel2(2000))
}

flexWebView.typeInterface("modelArgsTest") { req: ArgsTestModel ->
    Log.i("ModelTest", req.testModel.data2.testInt) // 2000
}

// in js
const test = async () => {
  const model = await $flex.modelTest(); // model is { name: 'test', data2: { testInt: 2000 } }
  await $flex.modelArgsTest({ testModel: model });
};
test();

Action Object

In the Web to Native interface, this is a method that can return a value from code other than the specified lambda code block.
Can return a value from the code at any location through the Action object.
At this time, the web will be in pending state until a response occurs. Also, the Action object once responded to cannot be used again.

var mAction: FlexAction? = null

flexWebView.setAction("actionTest") { action, args ->
    val mLocationRequest = getLocationRequest()
    val mFusedLocationClient = LocationServices.getFusedLocationProviderClient(context)
    if (mFusedLocationClient == null) {
        action.reject("location client is null")
        return@setAction
    }
    mAction = action
    mFusedLocationClient.requestLocationUpdates(mLocationRequest, mLocationCallback, null)
}

private val mLocationCallback = object : LocationCallback() {
    override fun onLocationResult(locationResult: LocationResult) {
        var mLastLocation: Location = locationResult.lastLocation
        val latitude = mLastLocation.latitude.toString()
        mAction?.promiseReturn(latitude)
    }
}

Separately declare lambda

This is a function for easily declaring and cleaning up lambdas that define behavior in interfaces.
It can be easily used through a function in which a returnable type-specific lambda is defined in the companion object of the FlexLambda class.
At this time, the type of args must be designated as FlexArguemts or Model Class.

val lambdaVar = FlexLambda.list { args: FlexArguments ->
    ... some job
}
val lambdaActionVar = FlexLambda.action { action, args: FlexArguments ->
    ... come job
}

flexWebView.setInterface("lamdaVarTest", lambda = lambdaVar)
flexWebView.setAction("lambdaActionVarTest", action = lambdaActionVar)

Web to native interface timeout setting

Since the interface operates asynchronously, there is a risk of falling into an infinite pending state in the Web.
So it can set the timeout of the interface, and when the timeout occurs, it will switch to reject.
If timeout is not set, the default value is 60000ms.

default timeout setting

You can specify a default value for timeout. If a per-interface timeout is not set, its value is set by default.
If set to 0, no timeout occurs and waits indefinitely.
The unit is ms.

val timeout = 1000
flexWebView.setInterfaceTimeout(timeout)

Specify timeout for each interface

When configuring the interface, you can specify the timeout of the interface.
If set to 0, no timeout occurs and waits indefinitely.
The unit is ms.

val timeout = 200
fletWebView.setInterface("funcName", timeout) {}

Interface thread settings

You can set the number of threads or CoroutineContext on which the interface will run.
All interfaces in Native operate within the CoroutineScope set by the corresponding thread pool/CoroutineContext.
If you specify both settings at the same time, the CoroutineContext setting takes precedence.
If not set, it acts as a CoroutineScope set to the number of threads equal to the number of mobile processors.

flexWebView.setCoroutineContext(mCoroutineContext)
flexWebView.setInterfaceThreadCount(threadCnt)

Interface event listener

You can listen to events about interface module initialization, interface success, failure, and timeout.

// Listen for specific events
flexWebView.addFlexEventListener(FlexEvent.EXCEPTION) { view, type, url, funcName, msg ->
    Log.i("Flex EXCEPTION", "type: ${type.name} url: $url funcName: $funcName msg: $msg")
}

// Listen to all events
val AllListener = { view, type, url, funcName, msg ->
    Log.i("Flex ALL Listen", "type: ${type.name} url: $url funcName: $funcName msg: $msg")
}
flexWebView.addFlexEventListener(AllListener)

// Remove specific EventListener
flexWebView.removeFlexEventListener(AllListener)

// Remove all EventListeners
flexWebView.removeAllFlexEventListener()

FlexWebView features

Default WebSetting

In FlexWebView, the following are basically declared among the WebSetting items of WebView.

settings.javaScriptEnabled = true
settings.displayZoomControls = false
settings.builtInZoomControls = false
settings.setSupportZoom(false)
settings.textZoom = 100
settings.domStorageEnabled = true
settings.loadWithOverviewMode = true
settings.loadsImagesAutomatically = true
settings.useWideViewPort = true
settings.cacheMode = WebSettings.LOAD_DEFAULT
settings.layoutAlgorithm = WebSettings.LayoutAlgorithm.SINGLE_COLUMN
settings.mediaPlaybackRequiresUserGesture = false
settings.enableSmoothTransition()
settings.javaScriptCanOpenWindowsAutomatically = true
settings.mixedContentMode = WebSettings.MIXED_CONTENT_ALWAYS_ALLOW
if(Build.VERSION.SDK_INT > Build.VERSION_CODES.O) {
    setRendererPriorityPolicy(RENDERER_PRIORITY_IMPORTANT, true)
}

FlexWebViewClient and FlexWebChromeClient

FlexWebView must use FlexWebViewClient and FlexWebChromeClient instead of WebViewClient and WebChromeClient.
FlexWebChromeClient provides full screen function, and FlexWebViewClient provides functions such as URL restriction and AssetLoader setting.

URL restrictions

This is a function to prevent unintended loading of sites and set whether to allow interfaces by URL.

BaseUrl

BaseUrl is a function that can be used to set only the availability of an interface without limiting the url.
If both AllowUrlList and BaseUrl are not set, FlexWebView allows access to all sites, but the interface function cannot be used.
If only BaseUrl is set, access to all sites is allowed and the interface function is opened only to URLs matching BaseUrl.

flexWebVeiw.baseUrl = "www.myurl.com"

If you want to specify a url that includes a wildcard subdomain, you can set the url starting with a '.'

flexWebVeiw.baseUrl = ".myurl.com"

You can also specify a URL in a regular expression.

AllowUrlList

If AllowUrlList is set, access to all urls except for the set urls and BaseUrl is blocked.

flexWebView.addAllowUrl(".myurl.com")

To allow the interface when setting the URL, add true to the second property of the addAllowUrl function.

flexWebView.addAllowUrl(".myurl.com", true)

FlexWebViewClient's notAllowedUrlLoad function can detect loading of restricted urls.

flexWebView.webViewClient = object : FlexWebViewClient() {
    override fun notAllowedUrlLoad(
        view: WebView,
        request: WebResourceRequest?,
        url: String?
    ) {
        super.notAllowedUrlLoad(view, request, url)
    }
}

Local file load

It provides comprehensive local file loading function of WebView.

AssetLoader

AssetLoader simple configuration function to access files in Asset.

flexWebview.setAssetsLoaderUse(true, "/assets/")
flexWebView.loadUrl("https://appassets.androidplatform.net/assets/my.html")

FileAccess

Ability to set allowFileAccess, allowFileAccessFromFileURLs, and allowUniversalAccessFromFileURLs items of basic WebSetting at once.

flexWebView.setAllowFileAccessAndUrlAccessInFile(true)

Fullscreen

Full-screen functions controlled by js can be used immediately.

// in js
document.documentElement.requestFullscreen();
document.exitFullscreen();

Use in js

$flex Object

$flex Object is an object composed of interfaces between FlexWebView and Promise.
$flex is declared in the webpage at runtime when the webpage is loaded in the webview.
When $flex is finished loading, you can check the window.onFlexLoad function.
$flex can also be used in any accessible frames. (Ex) iframe that does not violate Cross-Origin)
The components of $ flex Object are as follows.

window.onFlexLoad; // $flex is called upon completion of loading.
$flex; // Object that contains functions that can call Native area as WebToNative
$flex.version; // get Library version
$flex.web; // Object used to add and use functions to be used for NativeToWeb
$flex.device; // Current Device Info
$flex.isAndroid; // true
$flex.isiOS; // false
$fles.isScript; // false

ToDo

Flutter version

Kyun-J/FlexHybridApp-Android

FlexibleHybrid

How to add libraries

Key Features

Basic usage of interface

Web to Nativew

Interface registration

Interface invoke

Natvie to Web

Interface registration

Interface invoke

Advanced usage of interface

FlexData and FlexArguemtns

Model Class

Action Object

Separately declare lambda

Web to native interface timeout setting

default timeout setting

Specify timeout for each interface

Interface thread settings

Interface event listener

FlexWebView features

Default WebSetting

FlexWebViewClient and FlexWebChromeClient

URL restrictions

BaseUrl

AllowUrlList

Local file load

AssetLoader

FileAccess

Fullscreen

Use in js

$flex Object

ToDo