Sample usage of WebViewCompat

Question

By accident I found that there is a support library for WebView that is part of AndroidX: androidx.webkit:webkit:1.0.0

However I could not find any sample code on how to use it and the JavaDoc is not much of a help either: https://developer.android.com/reference/androidx/webkit/package-summary

Is this supposed to be used by developers or is it an internal library?

Answer 1

This library is an androidx abstraction for WebKit (as it relies on an update-able APK).

WebViewCompat.java itself tells "do not instantiate this" (and also the XML tag is unknown, so one has to use android.webkit.WebView); but class WebViewCompat has several public static methods, which are accessible; Also WebViewFeature seems relevant (the IDE complained).

When using these imports:

import android.webkit.WebResourceRequest;
import android.webkit.WebResourceResponse;
import android.webkit.WebSettings;
import android.webkit.WebView;

import androidx.annotation.NonNull;

import androidx.webkit.SafeBrowsingResponseCompat;
import androidx.webkit.WebResourceErrorCompat;
import androidx.webkit.WebViewClientCompat;
import androidx.webkit.WebViewFeature;
import androidx.webkit.WebViewCompat;

using WebViewClientCompat works about like this:

private WebView mWebView;

...
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {

    this.mWebView.setWebViewClient(new WebViewClientCompat(){

        @Override
        public void onPageCommitVisible(@NonNull WebView view, @NonNull String url) {
            super.onPageCommitVisible(view, url);
        }

        @Override
        public void onReceivedError(@NonNull WebView view, @NonNull WebResourceRequest request, @NonNull WebResourceErrorCompat error) {
            super.onReceivedError(view, request, error);
        }

        @Override
        public void onReceivedHttpError(@NonNull WebView view, @NonNull WebResourceRequest request, @NonNull WebResourceResponse errorResponse) {
            super.onReceivedHttpError(view, request, errorResponse);
        }

        @Override
        public void onSafeBrowsingHit(@NonNull WebView view, @NonNull WebResourceRequest request, int threatType, @NonNull SafeBrowsingResponseCompat callback) {
            super.onSafeBrowsingHit(view, request, threatType, callback);
        }

        @Override
        public boolean shouldOverrideUrlLoading(@NonNull WebView view, @NonNull WebResourceRequest request) {
            return super.shouldOverrideUrlLoading(view, request);
        }
    });
}

implementing interface WebViewCompat.VisualStateCallback works alike this:

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M && WebViewFeature.isFeatureSupported(WebViewFeature.VISUAL_STATE_CALLBACK)) {
    final int mVisualStateCallbackId = 500;
    WebViewCompat.postVisualStateCallback(mWebView, mVisualStateCallbackId, new WebViewCompat.VisualStateCallback() {
        @Override
        public void onComplete(long requestId) {
            if (requestId == mVisualStateCallbackId) {
                mWebView.setVisibility(View.VISIBLE);
            }
        }
    });
}