Fix history issues

src/main/java/edu/kit/typicalc/view/main/InputBar.java

@@ -38,6 +38,7 @@ public class InputBar extends HorizontalLayout implements LocaleChangeObserver {
 
     private static final short MAX_INPUT_LENGTH = 1000;
 
+    private final transient Consumer<Pair<String, Map<String, String>>> callback;
     private final TextField inputField;
     private TypeAssumptionsArea typeAssumptionsArea;
     private final Button inferTypeButton;
@@ -50,6 +51,8 @@ public class InputBar extends HorizontalLayout implements LocaleChangeObserver {
      * @param callback Consumer to call the inferType()-method in UpperBar
      */
     protected InputBar(Consumer<Pair<String, Map<String, String>>> callback) {
+        this.callback = callback;
+
         Button infoIcon = new Button(new Icon(VaadinIcon.INFO_CIRCLE));
         infoIcon.addClickListener(event -> onInfoIconClick());
 
@@ -78,7 +81,7 @@ public class InputBar extends HorizontalLayout implements LocaleChangeObserver {
         typeAssumptionsArea = new TypeAssumptionsArea();
         Button exampleButton = new Button(VaadinIcon.PAPERCLIP.create(), event -> onExampleButtonClick());
         exampleButton.setId(EXAMPLE_BUTTON_ID);
-        inferTypeButton = new Button("", event -> onTypeInferButtonClick(callback));
+        inferTypeButton = new Button("", event -> onTypeInferButtonClick());
         inferTypeButton.addClickShortcut(Key.ENTER).listenOn(this);
         inferTypeButton.addThemeVariants(ButtonVariant.LUMO_PRIMARY);
         inferTypeButton.setId(INFER_BUTTON_ID);
@@ -88,13 +91,12 @@ public class InputBar extends HorizontalLayout implements LocaleChangeObserver {
     }
 
     /**
-     * Sets the provided string as the value of the inputField and starts the type inference algorithm.
+     * Sets the provided string as the value of the inputField.
      *
      * @param term the provided string
      */
-    protected void inferTerm(String term) {
+    protected void setTerm(String term) {
         inputField.setValue(term);
-        UI.getCurrent().getPage().executeJs("document.getElementById($0).click()", INFER_BUTTON_ID);
     }
 
     /**
@@ -106,15 +108,10 @@ public class InputBar extends HorizontalLayout implements LocaleChangeObserver {
         typeAssumptionsArea = new TypeAssumptionsArea(typeAssumptions);
     }
 
-    private void onTypeInferButtonClick(Consumer<Pair<String, Map<String, String>>> callback) {
+    private void onTypeInferButtonClick() {
         String currentInput = inputField.getOptionalValue().orElse(StringUtils.EMPTY);
         inputField.blur();
 
-        if ("".equals(currentInput)) {
-            UI.getCurrent().getPage().setTitle(getTranslation("root.typicalc"));
-        } else {
-            UI.getCurrent().getPage().setTitle(getTranslation("root.typicalc") + " - " + currentInput);
-        }
         callback.accept(Pair.of(currentInput, typeAssumptionsArea.getTypeAssumptions()));
     }
 
@@ -123,7 +120,7 @@ public class InputBar extends HorizontalLayout implements LocaleChangeObserver {
     }
 
     private void onExampleButtonClick() {
-        Dialog exampleDialog = new ExampleDialog(this::inferTerm);
+        Dialog exampleDialog = new ExampleDialog(this::setTerm);
         exampleDialog.open();
     }
 

src/main/java/edu/kit/typicalc/view/main/MainViewImpl.java

@@ -20,6 +20,7 @@ import java.nio.charset.StandardCharsets;
 import java.util.Collections;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.stream.Collectors;
 
 /**
@@ -41,6 +42,7 @@ public class MainViewImpl extends AppLayout
     public static final String PAGE_TITLE = "Typicalc";
 
     private final UpperBar upperBar;
+    private transient Optional<TypeInferenceView> tiv = Optional.empty();
 
     /**
      * Creates a new MainViewImpl.
@@ -55,8 +57,8 @@ public class MainViewImpl extends AppLayout
 
     @Override
     public void setTypeInferenceView(TypeInfererInterface typeInferer) {
-        TypeInferenceView tiv = new TypeInferenceView(typeInferer);
+        tiv = Optional.of(new TypeInferenceView(typeInferer));
-        setContent(tiv);
+        setContent(tiv.get());
     }
 
     @Override
@@ -67,6 +69,7 @@ public class MainViewImpl extends AppLayout
 
     @Override
     public void beforeEnter(BeforeEnterEvent event) {
+        tiv = Optional.empty();
         if (event.getLocation().getPath().matches(TypeInferenceView.ROUTE + "/.*")) {
             Location url = event.getLocation();
             List<String> segments = url.getSegments();
@@ -83,6 +86,11 @@ public class MainViewImpl extends AppLayout
         }
     }
 
+    @Override
+    protected void afterNavigation() {
+        // this method ensures that the content is visible after navigation
+        tiv.ifPresent(this::setContent);
+    }
 
     private void setTermInURL(Pair<String, Map<String, String>> lambdaTermAndAssumptions) {
         String lambdaTerm = lambdaTermAndAssumptions.getLeft();
@@ -99,7 +107,7 @@ public class MainViewImpl extends AppLayout
         if (types.length() > 0) {
             typeAssumptions = "?" + types.toString();
         }
-        UI.getCurrent().getPage().getHistory().replaceState(null,
+        UI.getCurrent().getPage().getHistory().pushState(null,
                 new Location(TypeInferenceView.ROUTE + "/" + lambdaTerm + typeAssumptions));
     }
 

src/main/java/edu/kit/typicalc/view/main/UpperBar.java

@@ -62,25 +62,30 @@ public class UpperBar extends HorizontalLayout {
     }
 
     /**
-     * Starts the type inference algorithm by passing the required arguments to the MainViewListener.
+     * Starts the type inference algorithm by passing the required arguments to the MainViewListener
+     * and updating the URL.
      *
      * @param termAndAssumptions the lambda term to be type-inferred and the type assumptions to use
      */
     protected void typeInfer(Pair<String, Map<String, String>> termAndAssumptions) {
         setTermInURL.accept(termAndAssumptions);
-        presenter.typeInferLambdaString(termAndAssumptions.getLeft(), termAndAssumptions.getRight());
+        startInfer(termAndAssumptions.getLeft(), termAndAssumptions.getRight());
+    }
+
+    private void startInfer(String term, Map<String, String> typeAssumptions) {
+        presenter.typeInferLambdaString(term, typeAssumptions);
     }
 
     /**
-     * Calls the inferTerm method in {@link InputBar} with the provided
+     * Sets the lambda term and type assumptions in the InputBar and starts the inference.
-     * string as the argument.
      *
      * @param term            the provided string
      * @param typeAssumptions type assumptions to use
      */
     protected void inferTerm(String term, Map<String, String> typeAssumptions) {
         inputBar.setTypeAssumptions(typeAssumptions);
-        inputBar.inferTerm(term);
+        inputBar.setTerm(term);
+        startInfer(term, typeAssumptions);
     }
 
     private void onHelpIconClick() {