WIP

bundles/org.eclipse.swt/Eclipse SWT Browser/common/org/eclipse/swt/browser/Browser.java

@@ -14,6 +14,7 @@
 package org.eclipse.swt.browser;
 
 import java.io.*;
+import java.net.*;
 import java.nio.file.*;
 
 import org.eclipse.swt.*;
@@ -58,18 +59,18 @@ public class Browser extends Composite {
 	/**
 	 * @since 3.127
 	 */
-	public static final String BASE_URL;
+	public static final URI BASE_URI;
 
 	static {
-		String absolutePath;
-			try {
-				Path tempFile = Files.createTempFile("base", ".html");
-				absolutePath = tempFile.toUri().toString();
-				tempFile.toFile().deleteOnExit();
-			} catch (IOException e) {
-				absolutePath = "about:blank";
-			}
-		BASE_URL = absolutePath;
+		URI absolutePath;
+		try {
+			Path tempFile = Files.createTempFile("base", ".html");
+			absolutePath = tempFile.toUri();
+			tempFile.toFile().deleteOnExit();
+		} catch (IOException e) {
+			absolutePath = URI.create("about:blank");
+		}
+		BASE_URI = absolutePath;
 	}
 
 /**

bundles/org.eclipse.swt/Eclipse SWT Browser/win32/org/eclipse/swt/browser/Edge.java

@@ -17,6 +17,7 @@
 import java.nio.charset.*;
 import java.time.*;
 import java.util.*;
+import java.util.concurrent.*;
 import java.util.function.*;
 
 import org.eclipse.swt.*;
@@ -64,6 +65,8 @@ public WebViewEnvironment(ICoreWebView2Environment environment) {
 	boolean inNewWindow;
 	HashMap<Long, LocationEvent> navigations = new HashMap<>();
 	private String html;
+	private boolean needsInitialization;
+	private CompletableFuture<Boolean> initializationProcess = new CompletableFuture<>();
 
 	static {
 		NativeClearSessions = () -> {
@@ -302,12 +305,12 @@ void checkDeadlock() {
 	// and JavaScript callbacks are serialized. An event handler waiting
 	// for a completion of another handler will deadlock. Detect this
 	// situation and throw an exception instead.
-	if (inCallback || inNewWindow) {
+	if (leadsToDeadlock()) {
 		SWT.error(SWT.ERROR_FAILED_EVALUATE, null, " [WebView2: deadlock detected]");
 	}
 }
 
-boolean isBusy() {
+boolean leadsToDeadlock() {
 	return inCallback || inNewWindow;
 }
 
@@ -376,14 +379,24 @@ WebViewEnvironment createEnvironment() {
 
 @Override
 public void create(Composite parent, int style) {
-	checkDeadlock();
+	// If leads to deadlock then schedule the call the method in a different thread and move on.
+	// The webview calls are queued to be executed when it is done executing the current task.
+	if (leadsToDeadlock() && !needsInitialization) {
+		needsInitialization = true;
+		browser.getDisplay().asyncExec(() -> create(parent, style));
+		return;
+	}
+	needsInitialization = false;
 	containingEnvironment = createEnvironment();
 
 	long[] ppv = new long[1];
 	int hr = containingEnvironment.environment().QueryInterface(COM.IID_ICoreWebView2Environment2, ppv);
 	if (hr == COM.S_OK) environment2 = new ICoreWebView2Environment2(ppv[0]);
 
 	hr = callAndWait(ppv, completion -> containingEnvironment.environment().CreateCoreWebView2Controller(browser.handle, completion));
+	if(browser.isDisposed()) {
+		return;
+	}
 	switch (hr) {
 	case COM.S_OK:
 		break;
@@ -458,6 +471,7 @@ public void completed(ProgressEvent event) {
 	browser.addListener(SWT.Move, this::browserMove);
 
 	containingEnvironment.instances().add(this);
+	initializationProcess.complete(true);
 }
 
 void browserDispose(Event event) {
@@ -863,7 +877,7 @@ public void stop() {
 }
 
 private void writeToDefaultPathDOM() {
-	if(html != null && URI.create(getUrl()).equals(URI.create(Browser.BASE_URL))) {
+	if(html != null && URI.create(getUrl()).equals(Browser.BASE_URI)) {
 		boolean test = jsEnabled;
 		jsEnabled = true;
 		execute("document.open(); document.write(`" + html + "`); document.close();");
@@ -874,17 +888,29 @@ private void writeToDefaultPathDOM() {
 
 @Override
 public boolean setText(String html, boolean trusted) {
-	return setWebpageData(Browser.BASE_URL, null, null, html);
+	return setWebpageData(Browser.BASE_URI.toASCIIString(), null, null, html);
 }
 
-private boolean setWebpageData(String url, String postData, String[] headers, String html) {
+private boolean setWebpageData(final String url, String postData, String[] headers, String html) {
+	// If the create() method hasn't finished executing, queue the call to wait for the browser to finish initializing
+	if (!initializationProcess.isDone()) {
+		browser.getDisplay().asyncExec(() -> {
+			waitForInitialization();
+			setWebpageData(url, postData, headers, html);
+			browserResize(new Event());
+		});
+		return true;
+	}
 	// Feature in WebView2. Partial URLs like "www.example.com" are not accepted.
 	// Prepend the protocol if it's missing.
+	final String normalisedUrl;
 	if (!url.matches("[a-z][a-z0-9+.-]*:.*")) {
-		url = "http://" + url;
+		normalisedUrl = "http://" + url;
+	} else {
+		normalisedUrl = url;
 	}
 	int hr;
-	char[] pszUrl = stringToWstr(url);
+	char[] pszUrl = stringToWstr(normalisedUrl);
 	this.html = html;
 	if (postData != null || headers != null) {
 		if (environment2 == null || webView_2 == null) {
@@ -920,6 +946,15 @@ private boolean setWebpageData(String url, String postData, String[] headers, St
 	return hr == COM.S_OK;
 }
 
+private void waitForInitialization() {
+	try {
+		initializationProcess.get(10, TimeUnit.SECONDS);
+	} catch (InterruptedException | ExecutionException | TimeoutException e) {
+		// TODO Auto-generated catch block
+		e.printStackTrace();
+	}
+}
+
 @Override
 public boolean setUrl(String url, String postData, String[] headers) {
 	return setWebpageData(url, postData, headers, null);

tests/org.eclipse.swt.tests/JUnit Tests/org/eclipse/swt/tests/junit/Test_org_eclipse_swt_browser_Browser.java

@@ -1131,7 +1131,8 @@ private void validateTitleChanged(String expectedTitle, Runnable browserSetFunc)
 	shell.open();
 
 	boolean hasFinished = waitForPassCondition(() -> actualTitle.get().length() != 0
-			&& !actualTitle.get().contains("about:blank")); // Windows sometimes does 2 loads, one "about:blank", and one actual load.
+			&& !actualTitle.get().contains("about:blank") // Windows sometimes does 2 loads, one "about:blank", and one actual load.
+			&& !Browser.BASE_URI.toASCIIString().contains(actualTitle.get())); // Edge Browser does 2 loads on setText, one for navigating to BASE_URL, and one actual load.
 	boolean passed = hasFinished && actualTitle.get().equals(expectedTitle);
 	String errMsg = "";
 	if (!hasFinished)