Merge branch 'develop' into feature/1690-invalid-config-handling

See: https://github.com/cryptomator/cryptomator/pull/1691#discussion_r650773723

README.md

@@ -56,7 +56,7 @@ Download native binaries of Cryptomator on [cryptomator.org](https://cryptomator
 - File names get encrypted
 - Folder structure gets obfuscated
 - Use as many vaults in your Dropbox as you want, each having individual passwords
-- Two thousand commits for the security of your data!! :tada:
+- Three thousand commits for the security of your data!! :tada:
 
 ### Privacy
 

src/main/java/org/cryptomator/common/mountpoint/MountPointChooser.java

@@ -34,11 +34,13 @@ import java.util.SortedSet;
  * this volume, even if {@code #prepare(Volume, Path)} fails.</i>
  *
  * <p>If {@code #chooseMountPoint(Volume)} yields no result, the next MPC is executed
- * <i>without</i> first calling the {@code #prepare(Volume, Path)} method of the current MPC.
+ * <i>without</i> calling the {@code #prepare(Volume, Path)} method of the current MPC first.
  * This is repeated until<br>
  * <ul>
  *     <li><b>either</b> a mountpoint is returned by {@code #chooseMountPoint(Volume)}
  *     and {@code #prepare(Volume, Path)} succeeds or fails, ending the entire operation</li>
+ *     <li><b>or</b> {@code #chooseMountPoint(Volume)} throws an exception,
+ *     ending the entire operation</li>
  *     <li><b>or</b> no MPC remains and an {@link InvalidMountPointException} is thrown.</li>
  * </ul>
  * If the {@code #prepare(Volume, Path)} method of a MPC fails, the entire
@@ -72,12 +74,13 @@ public interface MountPointChooser {
 	 * Developers should override this method to find or extract a mountpoint for
 	 * the volume <b>without</b> preparing it. Preparation should be done by
 	 * {@link #prepare(Volume, Path)} instead.
-	 * Exceptions in this method should be handled gracefully and result in returning
-	 * {@link Optional#empty()} instead of throwing an exception.
+	 * The Mountpoint-Choosing-Operation will fail if an exception occurs.
+	 * Consequently developers should try to restrict throwing exceptions to those cases where
+	 * aborting the entire operation is sensible. Failure to choose a suitable path should
+	 * be indicated by returning {@link Optional#empty()} instead.
 	 *
 	 * @param caller The Volume that is calling the method to choose a mountpoint
-	 * @return the chosen path or {@link Optional#empty()} if an exception occurred
-	 * or no mountpoint could be found.
+	 * @return the chosen path or {@link Optional#empty()} if no mountpoint could be found.
 	 * @see #isApplicable(Volume)
 	 * @see #prepare(Volume, Path)
 	 */

src/main/java/org/cryptomator/common/settings/InvalidSetting.java

@@ -0,0 +1,54 @@
+package org.cryptomator.common.settings;
+
+import java.net.URI;
+import java.util.Objects;
+import java.util.ResourceBundle;
+
+public enum InvalidSetting {
+
+	;
+
+	private final static String DEFAULT_TRACKER = "https://github.com/cryptomator/cryptomator/issues/";
+	private final static ResourceBundle BUNDLE = ResourceBundle.getBundle("i18n.strings");
+	private final static String UNKNOWN_KEY_FORMAT = "<Unknown key: %s>";
+
+	private final URI issue;
+	private final String resourceKey;
+
+	InvalidSetting(URI issue, String resourceKey) {
+		this.issue = issue;
+		this.resourceKey = Objects.requireNonNull(resourceKey);
+	}
+
+	InvalidSetting(int issueId, String resourceKey) {
+		this(onDefaultTracker(issueId), Objects.requireNonNull(resourceKey));
+	}
+
+	/**
+	 * Returns the corresponding issue URI of this setting.<br>
+	 * The issue URI usually resolves to a page on the
+	 * <a href="https://github.com/cryptomator/cryptomator/issues">Cryptomator Bugtracker.</a>
+	 *
+	 * @return the issue URI or {@code null} if none is provided.
+	 */
+	public URI getIssueURI() {
+		return this.issue;
+	}
+
+	/**
+	 * Returns a (preferably localized) message, that helps the user understand the
+	 * issue in their configuration and how to fix it.
+	 *
+	 * @return the non-null description of the issue.
+	 */
+	public String getMessage() {
+		if (!BUNDLE.containsKey(this.resourceKey)) {
+			return UNKNOWN_KEY_FORMAT.formatted(this.resourceKey);
+		}
+		return BUNDLE.getString(this.resourceKey);
+	}
+
+	private static URI onDefaultTracker(int id) {
+		return URI.create(DEFAULT_TRACKER + id);
+	}
+}

src/main/java/org/cryptomator/common/settings/InvalidSettingException.java

@@ -0,0 +1,41 @@
+package org.cryptomator.common.settings;
+
+
+public class InvalidSettingException extends RuntimeException {
+
+	private final InvalidSetting reason;
+	private final String additionalMessage;
+
+	public InvalidSettingException(InvalidSetting reason) {
+		this(reason, null, null);
+	}
+
+	public InvalidSettingException(InvalidSetting reason, String additionalMessage) {
+		this(reason, additionalMessage, null);
+	}
+
+	public InvalidSettingException(InvalidSetting reason, Throwable cause) {
+		this(reason, null, cause);
+	}
+
+	public InvalidSettingException(InvalidSetting reason, String additionalMessage, Throwable cause) {
+		super(composeMessage(reason, additionalMessage), cause);
+		this.reason = reason;
+		this.additionalMessage = additionalMessage;
+	}
+
+	public InvalidSetting getReason() {
+		return this.reason;
+	}
+
+	public String getAdditionalMessage() {
+		return this.additionalMessage;
+	}
+
+	private static String composeMessage(InvalidSetting reason, String additionalMessage) {
+		if (additionalMessage == null) {
+			return reason.getMessage();
+		}
+		return reason.getMessage() + "Additionally: " + additionalMessage;
+	}
+}

src/main/java/org/cryptomator/ui/controls/FontAwesome5IconView.java

@@ -21,8 +21,8 @@ public class FontAwesome5IconView extends Text {
 	private static final String FONT_PATH = "/css/fontawesome5-free-solid.otf";
 	private static final Font FONT;
 
-	private ObjectProperty<FontAwesome5Icon> glyph = new SimpleObjectProperty<>(this, "glyph", DEFAULT_GLYPH);
-	private DoubleProperty glyphSize = new SimpleDoubleProperty(this, "glyphSize", DEFAULT_GLYPH_SIZE);
+	private final ObjectProperty<FontAwesome5Icon> glyph = new SimpleObjectProperty<>(this, "glyph", DEFAULT_GLYPH);
+	private final DoubleProperty glyphSize = new SimpleDoubleProperty(this, "glyphSize", DEFAULT_GLYPH_SIZE);
 
 	static {
 		try {
@@ -42,7 +42,7 @@ public class FontAwesome5IconView extends Text {
 	}
 
 	private void glyphChanged(@SuppressWarnings("unused") ObservableValue<? extends FontAwesome5Icon> observable, @SuppressWarnings("unused") FontAwesome5Icon oldValue, FontAwesome5Icon newValue) {
-		setText(newValue.unicode());
+		setText(newValue == null ? null : newValue.unicode());
 	}
 
 	private void glyphSizeChanged(@SuppressWarnings("unused") ObservableValue<? extends Number> observable, @SuppressWarnings("unused") Number oldValue, Number newValue) {

src/main/java/org/cryptomator/ui/health/BatchService.java

@@ -16,7 +16,6 @@ public class BatchService extends Service<Void> {
 
 	private final Iterator<HealthCheckTask> remainingTasks;
 
-	@Inject
 	public BatchService(Iterable<HealthCheckTask> tasks) {
 		this.remainingTasks = tasks.iterator();
 	}

src/main/java/org/cryptomator/ui/health/CheckDetailController.java

@@ -23,7 +23,7 @@ import java.util.stream.Stream;
 @HealthCheckScoped
 public class CheckDetailController implements FxController {
 
-	private final EasyObservableList<DiagnosticResult> results;
+	private final EasyObservableList<Result> results;
 	private final OptionalBinding<Worker.State> taskState;
 	private final Binding<String> taskName;
 	private final Binding<String> taskDuration;
@@ -39,7 +39,7 @@ public class CheckDetailController implements FxController {
 	private final ResultListCellFactory resultListCellFactory;
 	private final ResourceBundle resourceBundle;
 
-	public ListView<DiagnosticResult> resultsListView;
+	public ListView<Result> resultsListView;
 	private Subscription resultSubscription;
 
 	@Inject
@@ -71,8 +71,8 @@ public class CheckDetailController implements FxController {
 		}
 	}
 
-	private Function<Stream<? extends DiagnosticResult>, Long> countSeverity(DiagnosticResult.Severity severity) {
-		return stream -> stream.filter(item -> severity.equals(item.getSeverity())).count();
+	private Function<Stream<? extends Result>, Long> countSeverity(DiagnosticResult.Severity severity) {
+		return stream -> stream.filter(item -> severity.equals(item.diagnosis().getSeverity())).count();
 	}
 
 	@FXML

src/main/java/org/cryptomator/ui/health/CheckListCell.java

@@ -1,13 +1,10 @@
 package org.cryptomator.ui.health;
 
+import org.cryptomator.cryptofs.health.api.DiagnosticResult;
 import org.cryptomator.ui.controls.FontAwesome5Icon;
 import org.cryptomator.ui.controls.FontAwesome5IconView;
 
 import javafx.beans.binding.Bindings;
-import javafx.beans.property.BooleanProperty;
-import javafx.beans.property.ObjectProperty;
-import javafx.beans.property.SimpleObjectProperty;
-import javafx.beans.value.ObservableValue;
 import javafx.concurrent.Worker;
 import javafx.geometry.Insets;
 import javafx.geometry.Pos;
@@ -15,101 +12,60 @@ import javafx.scene.Node;
 import javafx.scene.control.CheckBox;
 import javafx.scene.control.ContentDisplay;
 import javafx.scene.control.ListCell;
-import javafx.util.Callback;
+import java.util.function.Predicate;
 
 class CheckListCell extends ListCell<HealthCheckTask> {
 
 	private final FontAwesome5IconView stateIcon = new FontAwesome5IconView();
-	private final Callback<HealthCheckTask, BooleanProperty> selectedGetter;
-	private final ObjectProperty<State> stateProperty;
-
 	private CheckBox checkBox = new CheckBox();
-	private BooleanProperty selectedProperty;
 
-	CheckListCell(Callback<HealthCheckTask, BooleanProperty> selectedGetter, ObservableValue<Boolean> switchIndicator) {
-		this.selectedGetter = selectedGetter;
-		this.stateProperty = new SimpleObjectProperty<>(State.SELECTION);
-		switchIndicator.addListener(this::changeState);
+	CheckListCell() {
 		setPadding(new Insets(6));
 		setAlignment(Pos.CENTER_LEFT);
 		setContentDisplay(ContentDisplay.LEFT);
 		getStyleClass().add("label");
 	}
 
-	private void changeState(ObservableValue<? extends Boolean> observableValue, boolean oldValue, boolean newValue) {
-		if (newValue) {
-			stateProperty.set(State.RUN);
-		} else {
-			stateProperty.set(State.SELECTION);
-		}
-	}
-
 	@Override
 	protected void updateItem(HealthCheckTask item, boolean empty) {
 		super.updateItem(item, empty);
 		if (item != null) {
 			setText(item.getTitle());
-		}
-		switch (stateProperty.get()) {
-			case SELECTION -> updateItemSelection(item, empty);
-			case RUN -> updateItemRun(item, empty);
-		}
-	}
-
-	private void updateItemSelection(HealthCheckTask item, boolean empty) {
-		if (!empty) {
-			setGraphic(checkBox);
-
-			if (selectedProperty != null) {
-				checkBox.selectedProperty().unbindBidirectional(selectedProperty);
-			}
-			selectedProperty = selectedGetter.call(item);
-			if (selectedProperty != null) {
-				checkBox.selectedProperty().bindBidirectional(selectedProperty);
-			}
-		} else {
-			setGraphic(null);
-			setText(null);
-		}
-	}
-
-	private void updateItemRun(HealthCheckTask item, boolean empty) {
-		if (item != null) {
-			item.stateProperty().addListener(this::stateChanged);
 			graphicProperty().bind(Bindings.createObjectBinding(() -> graphicForState(item.getState()), item.stateProperty()));
-			stateIcon.setGlyph(glyphForState(item.getState()));
+			stateIcon.glyphProperty().bind(Bindings.createObjectBinding(() -> glyphForState(item), item.stateProperty()));
+			checkBox.selectedProperty().bindBidirectional(item.chosenForExecutionProperty());
 		} else {
 			graphicProperty().unbind();
 			setGraphic(null);
 			setText(null);
+			checkBox.selectedProperty().unbind();
 		}
 	}
 
-	private void stateChanged(ObservableValue<? extends Worker.State> observable, Worker.State oldState, Worker.State newState) {
-		stateIcon.setGlyph(glyphForState(newState));
-		stateIcon.setVisible(true);
-	}
-
 	private Node graphicForState(Worker.State state) {
 		return switch (state) {
-			case READY -> null;
+			case READY -> checkBox;
 			case SCHEDULED, RUNNING, FAILED, CANCELLED, SUCCEEDED -> stateIcon;
 		};
 	}
 
-	private FontAwesome5Icon glyphForState(Worker.State state) {
-		return switch (state) {
+	private FontAwesome5Icon glyphForState(HealthCheckTask item) {
+		return switch (item.getState()) {
 			case READY -> FontAwesome5Icon.COG; //just a placeholder
 			case SCHEDULED -> FontAwesome5Icon.CLOCK;
 			case RUNNING -> FontAwesome5Icon.SPINNER;
 			case FAILED -> FontAwesome5Icon.EXCLAMATION_TRIANGLE;
 			case CANCELLED -> FontAwesome5Icon.BAN;
-			case SUCCEEDED -> FontAwesome5Icon.CHECK;
+			case SUCCEEDED -> checkFoundProblems(item) ? FontAwesome5Icon.EXCLAMATION_TRIANGLE : FontAwesome5Icon.CHECK;
 		};
 	}
 
-	private enum State {
-		SELECTION,
-		RUN;
+	private boolean checkFoundProblems(HealthCheckTask item) {
+		Predicate<DiagnosticResult.Severity> isProblem = severity -> switch (severity) {
+			case WARN, CRITICAL -> true;
+			case INFO, GOOD -> false;
+		};
+		return item.results().stream().map(Result::diagnosis).map(DiagnosticResult::getSeverity).anyMatch(isProblem);
 	}
+
 }

src/main/java/org/cryptomator/ui/health/CheckListController.java

@@ -1,6 +1,7 @@
 package org.cryptomator.ui.health;
 
 import com.google.common.base.Preconditions;
+import com.google.common.base.Predicates;
 import com.tobiasdiez.easybind.EasyBind;
 import dagger.Lazy;
 import org.cryptomator.ui.common.ErrorComponent;
@@ -10,28 +11,24 @@ import org.slf4j.LoggerFactory;
 
 import javax.inject.Inject;
 import javafx.beans.binding.Binding;
+import javafx.beans.binding.Bindings;
 import javafx.beans.binding.BooleanBinding;
+import javafx.beans.binding.IntegerBinding;
 import javafx.beans.property.BooleanProperty;
-import javafx.beans.property.IntegerProperty;
 import javafx.beans.property.ObjectProperty;
 import javafx.beans.property.SimpleBooleanProperty;
-import javafx.beans.property.SimpleIntegerProperty;
 import javafx.beans.property.SimpleObjectProperty;
-import javafx.beans.value.ObservableValue;
 import javafx.collections.FXCollections;
 import javafx.collections.ObservableList;
+import javafx.collections.transformation.FilteredList;
 import javafx.concurrent.Worker;
 import javafx.event.ActionEvent;
 import javafx.fxml.FXML;
 import javafx.scene.control.CheckBox;
 import javafx.scene.control.ListView;
-import javafx.scene.control.cell.CheckBoxListCell;
 import javafx.stage.Stage;
-import javafx.util.StringConverter;
 import java.io.IOException;
-import java.util.Collection;
-import java.util.HashMap;
-import java.util.Map;
+import java.util.List;
 import java.util.Set;
 import java.util.concurrent.ExecutorService;
 
@@ -43,6 +40,7 @@ public class CheckListController implements FxController {
 
 	private final Stage window;
 	private final ObservableList<HealthCheckTask> tasks;
+	private final FilteredList<HealthCheckTask> chosenTasks;
 	private final ReportWriter reportWriter;
 	private final ExecutorService executorService;
 	private final ObjectProperty<HealthCheckTask> selectedTask;
@@ -50,19 +48,18 @@ public class CheckListController implements FxController {
 	private final SimpleObjectProperty<Worker<?>> runningTask;
 	private final Binding<Boolean> running;
 	private final Binding<Boolean> finished;
-	private final Map<HealthCheckTask, BooleanProperty> listPickIndicators;
-	private final IntegerProperty numberOfPickedChecks;
+	private final IntegerBinding chosenTaskCount;
 	private final BooleanBinding anyCheckSelected;
 	private final BooleanProperty showResultScreen;
 
 	/* FXML */
 	public ListView<HealthCheckTask> checksListView;
 
-
 	@Inject
-	public CheckListController(@HealthCheckWindow Stage window, Lazy<Collection<HealthCheckTask>> tasks, ReportWriter reportWriteTask, ObjectProperty<HealthCheckTask> selectedTask, ExecutorService executorService, Lazy<ErrorComponent.Builder> errorComponentBuilder) {
+	public CheckListController(@HealthCheckWindow Stage window, Lazy<List<HealthCheckTask>> tasks, ReportWriter reportWriteTask, ObjectProperty<HealthCheckTask> selectedTask, ExecutorService executorService, Lazy<ErrorComponent.Builder> errorComponentBuilder) {
 		this.window = window;
-		this.tasks = FXCollections.observableArrayList(tasks.get());
+		this.tasks = FXCollections.observableList(tasks.get(), HealthCheckTask::observables);
+		this.chosenTasks = this.tasks.filtered(HealthCheckTask::isChosenForExecution);
 		this.reportWriter = reportWriteTask;
 		this.executorService = executorService;
 		this.selectedTask = selectedTask;
@@ -70,13 +67,7 @@ public class CheckListController implements FxController {
 		this.runningTask = new SimpleObjectProperty<>();
 		this.running = EasyBind.wrapNullable(runningTask).mapObservable(Worker::runningProperty).orElse(false);
 		this.finished = EasyBind.wrapNullable(runningTask).mapObservable(Worker::stateProperty).map(END_STATES::contains).orElse(false);
-		this.listPickIndicators = new HashMap<>();
-		this.numberOfPickedChecks = new SimpleIntegerProperty(0);
-		this.tasks.forEach(task -> {
-			var entrySelectedProp = new SimpleBooleanProperty(false);
-			entrySelectedProp.addListener((observable, oldValue, newValue) -> numberOfPickedChecks.set(numberOfPickedChecks.get() + (newValue ? 1 : -1)));
-			listPickIndicators.put(task, entrySelectedProp);
-		});
+		this.chosenTaskCount = Bindings.size(this.chosenTasks);
 		this.anyCheckSelected = selectedTask.isNotNull();
 		this.showResultScreen = new SimpleBooleanProperty(false);
 	}
@@ -84,27 +75,31 @@ public class CheckListController implements FxController {
 	@FXML
 	public void initialize() {
 		checksListView.setItems(tasks);
-		checksListView.setCellFactory(view -> new CheckListCell(listPickIndicators::get, showResultScreen));
+		checksListView.setCellFactory(view -> new CheckListCell());
 		selectedTask.bind(checksListView.getSelectionModel().selectedItemProperty());
 	}
 
 	@FXML
 	public void toggleSelectAll(ActionEvent event) {
 		if (event.getSource() instanceof CheckBox c) {
-			listPickIndicators.forEach( (task, pickProperty) -> pickProperty.set(c.isSelected()));
+			tasks.forEach(t -> t.chosenForExecutionProperty().set(c.isSelected()));
 		}
 	}
 
 	@FXML
 	public void runSelectedChecks() {
 		Preconditions.checkState(runningTask.get() == null);
-		var batch = checksListView.getItems().filtered(item -> listPickIndicators.get(item).get());
-		var batchService = new BatchService(batch);
+
+		// prevent further interaction by cancelling non-chosen tasks:
+		tasks.filtered(Predicates.not(chosenTasks::contains)).forEach(HealthCheckTask::cancel);
+
+		// run chosen tasks:
+		var batchService = new BatchService(chosenTasks);
 		batchService.setExecutor(executorService);
 		batchService.start();
 		runningTask.set(batchService);
 		showResultScreen.set(true);
-		checksListView.getSelectionModel().select(batch.get(0));
+		checksListView.getSelectionModel().select(chosenTasks.get(0));
 		checksListView.refresh();
 		window.sizeToScene();
 	}
@@ -158,13 +153,12 @@ public class CheckListController implements FxController {
 		return showResultScreen;
 	}
 
-	public int getNumberOfPickedChecks() {
-		return numberOfPickedChecks.get();
+	public int getChosenTaskCount() {
+		return chosenTaskCount.getValue();
 	}
 
-	public IntegerProperty numberOfPickedChecksProperty() {
-		return numberOfPickedChecks;
+	public IntegerBinding chosenTaskCountProperty() {
+		return chosenTaskCount;
 	}
 
-
 }

src/main/java/org/cryptomator/ui/health/DummyHealthChecks.java

@@ -0,0 +1,41 @@
+package org.cryptomator.ui.health;
+
+import org.cryptomator.cryptofs.VaultConfig;
+import org.cryptomator.cryptofs.health.api.DiagnosticResult;
+import org.cryptomator.cryptofs.health.api.HealthCheck;
+import org.cryptomator.cryptolib.api.Cryptor;
+import org.cryptomator.cryptolib.api.Masterkey;
+
+import java.nio.file.Path;
+import java.util.function.Consumer;
+
+/**
+ * FIXME: Remove in production release
+ */
+public class DummyHealthChecks {
+
+	public static class DummyCheck1 implements HealthCheck {
+
+		@Override
+		public void check(Path path, VaultConfig vaultConfig, Masterkey masterkey, Cryptor cryptor, Consumer<DiagnosticResult> consumer) {
+			// no-op
+		}
+	}
+
+	public static class DummyCheck2 implements HealthCheck {
+
+		@Override
+		public void check(Path path, VaultConfig vaultConfig, Masterkey masterkey, Cryptor cryptor, Consumer<DiagnosticResult> consumer) {
+			// no-op
+		}
+	}
+
+	public static class DummyCheck3 implements HealthCheck {
+
+		@Override
+		public void check(Path path, VaultConfig vaultConfig, Masterkey masterkey, Cryptor cryptor, Consumer<DiagnosticResult> consumer) {
+			// no-op
+		}
+	}
+
+}

src/main/java/org/cryptomator/ui/health/HealthCheckModule.java

@@ -19,8 +19,6 @@ import org.cryptomator.ui.keyloading.KeyLoadingComponent;
 import org.cryptomator.ui.keyloading.KeyLoadingStrategy;
 import org.cryptomator.ui.mainwindow.MainWindow;
 
-import javax.annotation.Nullable;
-import javax.inject.Named;
 import javax.inject.Provider;
 import javafx.beans.property.ObjectProperty;
 import javafx.beans.property.SimpleObjectProperty;
@@ -30,6 +28,7 @@ import javafx.stage.Modality;
 import javafx.stage.Stage;
 import java.security.SecureRandom;
 import java.util.Collection;
+import java.util.List;
 import java.util.Map;
 import java.util.Optional;
 import java.util.ResourceBundle;
@@ -65,7 +64,7 @@ abstract class HealthCheckModule {
 	/* Only inject with Lazy-Wrapper!*/
 	@Provides
 	@HealthCheckScoped
-	static Collection<HealthCheckTask> provideAvailableHealthCheckTasks(Collection<HealthCheck> availableHealthChecks, @HealthCheckWindow Vault vault, AtomicReference<Masterkey> masterkeyRef, AtomicReference<VaultConfig> vaultConfigRef, SecureRandom csprng, ResourceBundle resourceBundle) {
+	static List<HealthCheckTask> provideAvailableHealthCheckTasks(Collection<HealthCheck> availableHealthChecks, @HealthCheckWindow Vault vault, AtomicReference<Masterkey> masterkeyRef, AtomicReference<VaultConfig> vaultConfigRef, SecureRandom csprng, ResourceBundle resourceBundle) {
 		return availableHealthChecks.stream().map(check -> new HealthCheckTask(vault.getPath(), vaultConfigRef.get(), masterkeyRef.get(), csprng, check, resourceBundle)).toList();
 	}
 

src/main/java/org/cryptomator/ui/health/HealthCheckTask.java

@@ -9,7 +9,10 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import javafx.application.Platform;
+import javafx.beans.Observable;
+import javafx.beans.property.BooleanProperty;
 import javafx.beans.property.LongProperty;
+import javafx.beans.property.SimpleBooleanProperty;
 import javafx.beans.property.SimpleLongProperty;
 import javafx.collections.FXCollections;
 import javafx.collections.ObservableList;
@@ -32,8 +35,9 @@ class HealthCheckTask extends Task<Void> {
 	private final Masterkey masterkey;
 	private final SecureRandom csprng;
 	private final HealthCheck check;
-	private final ObservableList<DiagnosticResult> results;
+	private final ObservableList<Result> results;
 	private final LongProperty durationInMillis;
+	private final BooleanProperty chosenForExecution;
 
 	public HealthCheckTask(Path vaultPath, VaultConfig vaultConfig, Masterkey masterkey, SecureRandom csprng, HealthCheck check, ResourceBundle resourceBundle) {
 		this.vaultPath = Objects.requireNonNull(vaultPath);
@@ -41,7 +45,7 @@ class HealthCheckTask extends Task<Void> {
 		this.masterkey = Objects.requireNonNull(masterkey);
 		this.csprng = Objects.requireNonNull(csprng);
 		this.check = Objects.requireNonNull(check);
-		this.results = FXCollections.observableArrayList();
+		this.results = FXCollections.observableArrayList(Result::observables);
 		try {
 			updateTitle(resourceBundle.getString("health." + check.identifier()));
 		} catch (MissingResourceException e) {
@@ -49,6 +53,7 @@ class HealthCheckTask extends Task<Void> {
 			updateTitle(check.identifier());
 		}
 		this.durationInMillis = new SimpleLongProperty(-1);
+		this.chosenForExecution = new SimpleBooleanProperty();
 	}
 
 	@Override
@@ -56,25 +61,14 @@ class HealthCheckTask extends Task<Void> {
 		Instant start = Instant.now();
 		try (var masterkeyClone = masterkey.clone(); //
 			 var cryptor = CryptorProvider.forScheme(vaultConfig.getCipherCombo()).provide(masterkeyClone, csprng)) {
-			check.check(vaultPath, vaultConfig, masterkeyClone, cryptor, result -> {
+			check.check(vaultPath, vaultConfig, masterkeyClone, cryptor, diagnosis -> {
 				if (isCancelled()) {
 					throw new CancellationException();
 				}
-				// FIXME: slowdown for demonstration purposes only:
-				try {
-					Thread.sleep(2000);
-				} catch (InterruptedException e) {
-					if (isCancelled()) {
-						return;
-					} else {
-						Thread.currentThread().interrupt();
-						throw new RuntimeException(e);
-					}
-				}
-				Platform.runLater(() -> results.add(result));
+				Platform.runLater(() -> results.add(Result.create(diagnosis)));
 			});
 		}
-		Platform.runLater(() ->durationInMillis.set(Duration.between(start, Instant.now()).toMillis()));
+		Platform.runLater(() -> durationInMillis.set(Duration.between(start, Instant.now()).toMillis()));
 		return null;
 	}
 
@@ -90,7 +84,11 @@ class HealthCheckTask extends Task<Void> {
 
 	/* Getter */
 
-	public ObservableList<DiagnosticResult> results() {
+	Observable[] observables() {
+		return new Observable[]{results, chosenForExecution};
+	}
+
+	public ObservableList<Result> results() {
 		return results;
 	}
 
@@ -106,4 +104,11 @@ class HealthCheckTask extends Task<Void> {
 		return durationInMillis.get();
 	}
 
+	public BooleanProperty chosenForExecutionProperty() {
+		return chosenForExecution;
+	}
+
+	public boolean isChosenForExecution() {
+		return chosenForExecution.get();
+	}
 }

src/main/java/org/cryptomator/ui/health/ReportWriter.java

@@ -72,7 +72,7 @@ public class ReportWriter {
 					case SUCCEEDED -> {
 						writer.write("STATUS: SUCCESS\nRESULTS:\n");
 						for (var result : task.results()) {
-							writer.write(REPORT_CHECK_RESULT.formatted(result.getSeverity(), result.toString()));
+							writer.write(REPORT_CHECK_RESULT.formatted(result.diagnosis().getSeverity(), result.getDescription()));
 						}
 					}
 					case CANCELLED -> writer.write("STATUS: CANCELED\n");

src/main/java/org/cryptomator/ui/health/Result.java

@@ -0,0 +1,43 @@
+package org.cryptomator.ui.health;
+
+import org.cryptomator.cryptofs.health.api.DiagnosticResult;
+
+import javafx.beans.Observable;
+import javafx.beans.property.ObjectProperty;
+import javafx.beans.property.SimpleObjectProperty;
+
+record Result(DiagnosticResult diagnosis, ObjectProperty<FixState> fixState) {
+
+	enum FixState {
+		NOT_FIXABLE,
+		FIXABLE,
+		FIXING,
+		FIXED,
+		FIX_FAILED
+	}
+
+	public static Result create(DiagnosticResult diagnosis) {
+		FixState initialState = switch (diagnosis.getSeverity()) {
+			case WARN -> FixState.FIXABLE;
+			default -> FixState.NOT_FIXABLE;
+		};
+		return new Result(diagnosis, new SimpleObjectProperty<>(initialState));
+	}
+
+	public Observable[] observables() {
+		return new Observable[]{fixState};
+	}
+
+	public String getDescription() {
+		return diagnosis.toString();
+	}
+
+	public FixState getState() {
+		return fixState.get();
+	}
+
+	public void setState(FixState state) {
+		this.fixState.set(state);
+	}
+
+}

src/main/java/org/cryptomator/ui/health/ResultFixApplier.java

@@ -10,20 +10,24 @@ import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
 import javax.inject.Inject;
-import javafx.scene.control.Alert;
+import javafx.application.Platform;
 import java.nio.file.Path;
 import java.security.SecureRandom;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionException;
+import java.util.concurrent.CompletionStage;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
 import java.util.concurrent.atomic.AtomicReference;
 
 @HealthCheckScoped
 class ResultFixApplier {
 
-	private static final Logger LOG = LoggerFactory.getLogger(ResultFixApplier.class);
-
 	private final Path vaultPath;
 	private final SecureRandom csprng;
 	private final Masterkey masterkey;
 	private final VaultConfig vaultConfig;
+	private final ExecutorService sequentialExecutor;
 
 	@Inject
 	public ResultFixApplier(@HealthCheckWindow Vault vault, AtomicReference<Masterkey> masterkeyRef, AtomicReference<VaultConfig> vaultConfigRef, SecureRandom csprng) {
@@ -31,18 +35,32 @@ class ResultFixApplier {
 		this.masterkey = masterkeyRef.get();
 		this.vaultConfig = vaultConfigRef.get();
 		this.csprng = csprng;
+		this.sequentialExecutor = Executors.newSingleThreadExecutor();
 	}
 
-	public void fix(DiagnosticResult result) {
-		Preconditions.checkArgument(result.getSeverity() == DiagnosticResult.Severity.WARN, "Unfixable result");
+	public CompletionStage<Void> fix(Result result) {
+		Preconditions.checkArgument(result.getState() == Result.FixState.FIXABLE);
+		result.setState(Result.FixState.FIXING);
+		return CompletableFuture.runAsync(() -> fix(result.diagnosis()), sequentialExecutor)
+				.whenCompleteAsync((unused, throwable) -> {
+					var fixed = throwable == null ? Result.FixState.FIXED : Result.FixState.FIX_FAILED;
+					result.setState(fixed);
+				}, Platform::runLater);
+	}
+
+	public void fix(DiagnosticResult diagnosis) {
+		Preconditions.checkArgument(diagnosis.getSeverity() == DiagnosticResult.Severity.WARN, "Unfixable result");
 		try (var masterkeyClone = masterkey.clone(); //
 			 var cryptor = CryptorProvider.forScheme(vaultConfig.getCipherCombo()).provide(masterkeyClone, csprng)) {
-			result.fix(vaultPath, vaultConfig, masterkeyClone, cryptor);
+			diagnosis.fix(vaultPath, vaultConfig, masterkeyClone, cryptor);
 		} catch (Exception e) {
-			LOG.error("Failed to apply fix", e);
-			Alert alert = new Alert(Alert.AlertType.ERROR, e.getMessage());
-			alert.showAndWait();
-			//TODO: real error/not supported handling
+			throw new FixFailedException(e);
+		}
+	}
+
+	public static class FixFailedException extends CompletionException {
+		private FixFailedException(Throwable cause) {
+			super(cause);
 		}
 	}
 }

src/main/java/org/cryptomator/ui/health/ResultListCellController.java

@@ -1,84 +1,89 @@
 package org.cryptomator.ui.health;
 
 import com.tobiasdiez.easybind.EasyBind;
-import org.cryptomator.cryptofs.health.api.DiagnosticResult;
+import com.tobiasdiez.easybind.optional.OptionalBinding;
 import org.cryptomator.ui.common.FxController;
 import org.cryptomator.ui.controls.FontAwesome5Icon;
 import org.cryptomator.ui.controls.FontAwesome5IconView;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 import javax.inject.Inject;
+import javafx.application.Platform;
 import javafx.beans.binding.Binding;
+import javafx.beans.binding.Bindings;
+import javafx.beans.binding.BooleanBinding;
+import javafx.beans.binding.ObjectBinding;
 import javafx.beans.property.ObjectProperty;
 import javafx.beans.property.SimpleObjectProperty;
-import javafx.beans.value.ObservableValue;
 import javafx.fxml.FXML;
 import javafx.scene.control.Button;
 
 // unscoped because each cell needs its own controller
 public class ResultListCellController implements FxController {
 
-	private final ResultFixApplier fixApplier;
-	private final ObjectProperty<DiagnosticResult> result;
+	private final Logger LOG = LoggerFactory.getLogger(ResultListCellController.class);
+
+	private final ObjectProperty<Result> result;
 	private final Binding<String> description;
+	private final ResultFixApplier fixApplier;
+	private final OptionalBinding<Result.FixState> fixState;
+	private final ObjectBinding<FontAwesome5Icon> glyph;
+	private final BooleanBinding fixable;
+	private final BooleanBinding fixing;
+	private final BooleanBinding fixed;
 
 	public FontAwesome5IconView iconView;
-	public Button actionButton;
+	public Button fixButton;
 
 	@Inject
 	public ResultListCellController(ResultFixApplier fixApplier) {
 		this.result = new SimpleObjectProperty<>(null);
-		this.description = EasyBind.wrapNullable(result).map(DiagnosticResult::toString).orElse("");
+		this.description = EasyBind.wrapNullable(result).map(Result::getDescription).orElse("");
 		this.fixApplier = fixApplier;
-		result.addListener(this::updateCellContent);
-	}
-
-	private void updateCellContent(ObservableValue<? extends DiagnosticResult> observable, DiagnosticResult oldVal, DiagnosticResult newVal) {
-		iconView.getStyleClass().clear();
-		actionButton.setVisible(false);
-		//TODO: see comment in case WARN
-		actionButton.setManaged(false);
-		switch (newVal.getSeverity()) {
-			case INFO -> {
-				iconView.setGlyph(FontAwesome5Icon.INFO_CIRCLE);
-				iconView.getStyleClass().add("glyph-icon-muted");
-			}
-			case GOOD -> {
-				iconView.setGlyph(FontAwesome5Icon.CHECK);
-				iconView.getStyleClass().add("glyph-icon-primary");
-			}
-			case WARN -> {
-				iconView.setGlyph(FontAwesome5Icon.EXCLAMATION_TRIANGLE);
-				iconView.getStyleClass().add("glyph-icon-orange");
-				//TODO: Neither is any fix implemented, nor it is ensured, that only fix is executed at a time with good ui indication
-				//	before both are not fix, do not show the button
-				//actionButton.setVisible(true);
-			}
-			case CRITICAL -> {
-				iconView.setGlyph(FontAwesome5Icon.TIMES);
-				iconView.getStyleClass().add("glyph-icon-red");
-			}
-		}
+		this.fixState = EasyBind.wrapNullable(result).mapObservable(Result::fixState);
+		this.glyph = Bindings.createObjectBinding(this::getGlyph, result);
+		this.fixable = Bindings.createBooleanBinding(this::isFixable, fixState);
+		this.fixing = Bindings.createBooleanBinding(this::isFixing, fixState);
+		this.fixed = Bindings.createBooleanBinding(this::isFixed, fixState);
 	}
 
 	@FXML
-	public void runResultAction() {
-		final var realResult = result.get();
-		if (realResult != null) {
-			fixApplier.fix(realResult);
+	public void initialize() {
+		// see getGlyph() for relevant glyphs:
+		EasyBind.includeWhen(iconView.getStyleClass(), "glyph-icon-muted", iconView.glyphProperty().isEqualTo(FontAwesome5Icon.INFO_CIRCLE));
+		EasyBind.includeWhen(iconView.getStyleClass(), "glyph-icon-primary", iconView.glyphProperty().isEqualTo(FontAwesome5Icon.CHECK));
+		EasyBind.includeWhen(iconView.getStyleClass(), "glyph-icon-orange", iconView.glyphProperty().isEqualTo(FontAwesome5Icon.EXCLAMATION_TRIANGLE));
+		EasyBind.includeWhen(iconView.getStyleClass(), "glyph-icon-red", iconView.glyphProperty().isEqualTo(FontAwesome5Icon.TIMES));
+	}
+
+	@FXML
+	public void fix() {
+		Result r = result.get();
+		if (r != null) {
+			fixApplier.fix(r).whenCompleteAsync(this::fixFinished, Platform::runLater);
 		}
 	}
+
+	private void fixFinished(Void unused, Throwable exception) {
+		if (exception != null) {
+			LOG.error("Failed to apply fix", exception);
+			// TODO ...
+		}
+	}
+
+
 	/* Getter & Setter */
 
-
-	public DiagnosticResult getResult() {
+	public Result getResult() {
 		return result.get();
 	}
 
-	public void setResult(DiagnosticResult result) {
+	public void setResult(Result result) {
 		this.result.set(result);
 	}
 
-	public ObjectProperty<DiagnosticResult> resultProperty() {
+	public ObjectProperty<Result> resultProperty() {
 		return result;
 	}
 
@@ -86,7 +91,49 @@ public class ResultListCellController implements FxController {
 		return description.getValue();
 	}
 
+	public ObjectBinding<FontAwesome5Icon> glyphProperty() {
+		return glyph;
+	}
+
+	public FontAwesome5Icon getGlyph() {
+		var r = result.get();
+		if (r == null) {
+			return null;
+		}
+		return switch (r.diagnosis().getSeverity()) {
+			case INFO -> FontAwesome5Icon.INFO_CIRCLE;
+			case GOOD -> FontAwesome5Icon.CHECK;
+			case WARN -> FontAwesome5Icon.EXCLAMATION_TRIANGLE;
+			case CRITICAL -> FontAwesome5Icon.TIMES;
+		};
+	}
+
 	public Binding<String> descriptionProperty() {
 		return description;
 	}
+
+	public BooleanBinding fixableProperty() {
+		return fixable;
+	}
+
+	public boolean isFixable() {
+		return fixState.get().map(Result.FixState.FIXABLE::equals).orElse(false);
+	}
+
+	public BooleanBinding fixingProperty() {
+		return fixing;
+	}
+
+	public boolean isFixing() {
+		return fixState.get().map(Result.FixState.FIXING::equals).orElse(false);
+	}
+
+	public BooleanBinding fixedProperty() {
+		return fixed;
+	}
+
+	public boolean isFixed() {
+		return fixState.get().map(Result.FixState.FIXED::equals).orElse(false);
+	}
+
 }

src/main/java/org/cryptomator/ui/health/ResultListCellFactory.java

@@ -1,7 +1,6 @@
 package org.cryptomator.ui.health;
 
 
-import org.cryptomator.cryptofs.health.api.DiagnosticResult;
 import org.cryptomator.ui.common.FxmlLoaderFactory;
 
 import javax.inject.Inject;
@@ -15,7 +14,7 @@ import java.io.IOException;
 import java.io.UncheckedIOException;
 
 @HealthCheckScoped
-public class ResultListCellFactory implements Callback<ListView<DiagnosticResult>, ListCell<DiagnosticResult>> {
+public class ResultListCellFactory implements Callback<ListView<Result>, ListCell<Result>> {
 
 	private final FxmlLoaderFactory fxmlLoaders;
 
@@ -25,7 +24,7 @@ public class ResultListCellFactory implements Callback<ListView<DiagnosticResult
 	}
 
 	@Override
-	public ListCell<DiagnosticResult> call(ListView<DiagnosticResult> param) {
+	public ListCell<Result> call(ListView<Result> param) {
 		try {
 			FXMLLoader fxmlLoader = fxmlLoaders.load("/fxml/health_result_listcell.fxml");
 			return new ResultListCellFactory.Cell(fxmlLoader.getRoot(), fxmlLoader.getController());
@@ -34,7 +33,7 @@ public class ResultListCellFactory implements Callback<ListView<DiagnosticResult
 		}
 	}
 
-	private static class Cell extends ListCell<DiagnosticResult> {
+	private static class Cell extends ListCell<Result> {
 
 		private final Parent node;
 		private final ResultListCellController controller;
@@ -45,7 +44,7 @@ public class ResultListCellFactory implements Callback<ListView<DiagnosticResult
 		}
 
 		@Override
-		protected void updateItem(DiagnosticResult item, boolean empty) {
+		protected void updateItem(Result item, boolean empty) {
 			super.updateItem(item, empty);
 			if (item == null || empty) {
 				setText(null);

src/main/java/org/cryptomator/ui/health/StartController.java

@@ -18,11 +18,16 @@ import org.slf4j.LoggerFactory;
 
 import javax.inject.Inject;
 import javafx.application.Platform;
+import javafx.beans.binding.BooleanBinding;
+import javafx.beans.property.ObjectProperty;
+import javafx.beans.property.SimpleObjectProperty;
 import javafx.fxml.FXML;
 import javafx.scene.Scene;
 import javafx.stage.Stage;
 import java.io.IOException;
-import java.util.Optional;
+import java.io.UncheckedIOException;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.CompletionException;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.atomic.AtomicReference;
 
@@ -31,38 +36,40 @@ public class StartController implements FxController {
 
 	private static final Logger LOG = LoggerFactory.getLogger(StartController.class);
 
+	private final Vault vault;
 	private final Stage window;
-	private final Optional<VaultConfig.UnverifiedVaultConfig> unverifiedVaultConfig;
+	private final CompletableFuture<VaultConfig.UnverifiedVaultConfig> unverifiedVaultConfig;
 	private final KeyLoadingStrategy keyLoadingStrategy;
 	private final ExecutorService executor;
 	private final AtomicReference<Masterkey> masterkeyRef;
 	private final AtomicReference<VaultConfig> vaultConfigRef;
 	private final Lazy<Scene> checkScene;
 	private final Lazy<ErrorComponent.Builder> errorComponent;
+	private final ObjectProperty<State> state = new SimpleObjectProperty<>(State.LOADING);
+	private final BooleanBinding loading = state.isEqualTo(State.LOADING);
+	private final BooleanBinding failed = state.isEqualTo(State.FAILED);
+	private final BooleanBinding loaded = state.isEqualTo(State.LOADED);
+
+	public enum State {
+		LOADING,
+		FAILED,
+		LOADED
+	}
 
 	/* FXML */
 
 	@Inject
 	public StartController(@HealthCheckWindow Vault vault, @HealthCheckWindow Stage window, @HealthCheckWindow KeyLoadingStrategy keyLoadingStrategy, ExecutorService executor, AtomicReference<Masterkey> masterkeyRef, AtomicReference<VaultConfig> vaultConfigRef, @FxmlScene(FxmlFile.HEALTH_CHECK_LIST) Lazy<Scene> checkScene, Lazy<ErrorComponent.Builder> errorComponent) {
+		this.vault = vault;
 		this.window = window;
+		this.unverifiedVaultConfig = CompletableFuture.supplyAsync(this::loadConfig, executor);
 		this.keyLoadingStrategy = keyLoadingStrategy;
 		this.executor = executor;
 		this.masterkeyRef = masterkeyRef;
 		this.vaultConfigRef = vaultConfigRef;
 		this.checkScene = checkScene;
 		this.errorComponent = errorComponent;
-
-		//TODO: this is ugly
-		//idea: delay the loading of the vault config and show a spinner (something like "check/load config") and react to the result of the loading
-		//or: load vault config in a previous step to see if it is loadable.
-		VaultConfig.UnverifiedVaultConfig tmp;
-		try {
-			tmp = vault.getUnverifiedVaultConfig();
-		} catch (IOException e) {
-			e.printStackTrace();
-			tmp =  null;
-		}
-		this.unverifiedVaultConfig = Optional.ofNullable(tmp);
+		this.unverifiedVaultConfig.whenCompleteAsync(this::loadedConfig, Platform::runLater);
 	}
 
 	@FXML
@@ -74,41 +81,64 @@ public class StartController implements FxController {
 	@FXML
 	public void next() {
 		LOG.trace("StartController.next()");
-		executor.submit(this::loadKey);
+		CompletableFuture.runAsync(this::loadKey, executor).whenCompleteAsync(this::loadedKey, Platform::runLater);
+	}
+
+	private VaultConfig.UnverifiedVaultConfig loadConfig() {
+		assert !Platform.isFxApplicationThread();
+		try {
+			return this.vault.getUnverifiedVaultConfig();
+		} catch (IOException e) {
+			throw new UncheckedIOException(e);
+		}
+	}
+
+	private void loadedConfig(VaultConfig.UnverifiedVaultConfig cfg, Throwable exception) {
+		assert Platform.isFxApplicationThread();
+		if (exception != null) {
+			state.set(State.FAILED);
+		} else {
+			assert cfg != null;
+			state.set(State.LOADED);
+		}
 	}
 
 	private void loadKey() {
 		assert !Platform.isFxApplicationThread();
-		assert unverifiedVaultConfig.isPresent();
-		try (var masterkey = keyLoadingStrategy.loadKey(unverifiedVaultConfig.orElseThrow().getKeyId())) {
-			var unverifiedCfg = unverifiedVaultConfig.get();
+		assert unverifiedVaultConfig.isDone();
+		var unverifiedCfg = unverifiedVaultConfig.join();
+		try (var masterkey = keyLoadingStrategy.loadKey(unverifiedCfg.getKeyId())) {
 			var verifiedCfg = unverifiedCfg.verify(masterkey.getEncoded(), unverifiedCfg.allegedVaultVersion());
 			vaultConfigRef.set(verifiedCfg);
 			var old = masterkeyRef.getAndSet(masterkey.clone());
 			if (old != null) {
 				old.destroy();
 			}
-			Platform.runLater(this::loadedKey);
 		} catch (MasterkeyLoadingFailedException e) {
 			if (keyLoadingStrategy.recoverFromException(e)) {
 				// retry
 				loadKey();
 			} else {
-				Platform.runLater(() -> loadingKeyFailed(e));
+				throw new LoadingFailedException(e);
 			}
-		} catch (VaultKeyInvalidException e) {
-			Platform.runLater(() -> loadingKeyFailed(e));
 		} catch (VaultConfigLoadException e) {
-			Platform.runLater(() -> loadingKeyFailed(e));
+			throw new LoadingFailedException(e);
 		}
 	}
 
-	private void loadedKey() {
-		LOG.debug("Loaded valid key");
-		window.setScene(checkScene.get());
+	private void loadedKey(Void unused, Throwable exception) {
+		assert Platform.isFxApplicationThread();
+		if (exception instanceof LoadingFailedException) {
+			loadingKeyFailed(exception.getCause());
+		} else if (exception != null) {
+			loadingKeyFailed(exception);
+		} else {
+			LOG.debug("Loaded valid key");
+			window.setScene(checkScene.get());
+		}
 	}
 
-	private void loadingKeyFailed(Exception e) {
+	private void loadingKeyFailed(Throwable e) {
 		if (e instanceof UnlockCancelledException) {
 			// ok
 		} else if (e instanceof VaultKeyInvalidException) {
@@ -120,8 +150,37 @@ public class StartController implements FxController {
 		}
 	}
 
-	public boolean isInvalidConfig() {
-		return unverifiedVaultConfig.isEmpty();
+	/* Getter */
+
+	public BooleanBinding loadingProperty() {
+		return loading;
 	}
 
+	public boolean isLoading() {
+		return loading.get();
+	}
+
+	public BooleanBinding failedProperty() {
+		return failed;
+	}
+
+	public boolean isFailed() {
+		return failed.get();
+	}
+
+	public BooleanBinding loadedProperty() {
+		return loaded;
+	}
+
+	public boolean isLoaded() {
+		return loaded.get();
+	}
+
+	/* internal types */
+
+	private static class LoadingFailedException extends CompletionException {
+		LoadingFailedException(Throwable cause) {
+			super(cause);
+		}
+	}
 }

src/main/java/org/cryptomator/ui/vaultoptions/HealthVaultOptionsController.java

@@ -12,6 +12,10 @@ import javafx.stage.Stage;
 @VaultOptionsScoped
 public class HealthVaultOptionsController implements FxController {
 
+	private final Stage window;
+	private final Vault vault;
+	private final HealthCheckComponent.Builder healthCheckWindow;
+
 	@Inject
 	public HealthVaultOptionsController(@VaultOptionsWindow Stage window, @VaultOptionsWindow Vault vault, HealthCheckComponent.Builder healthCheckWindow) {
 		this.window = window;
@@ -23,8 +27,4 @@ public class HealthVaultOptionsController implements FxController {
 	public void startHealthCheck(ActionEvent event) {
 		healthCheckWindow.vault(vault).windowToClose(window).build().showHealthCheckWindow();
 	}
-
-	private final Stage window;
-	private final Vault vault;
-	private final HealthCheckComponent.Builder healthCheckWindow;
 }

src/main/resources/META-INF/services/org.cryptomator.cryptofs.health.api.HealthCheck

@@ -0,0 +1,3 @@
+org.cryptomator.ui.health.DummyHealthChecks$DummyCheck1
+org.cryptomator.ui.health.DummyHealthChecks$DummyCheck2
+org.cryptomator.ui.health.DummyHealthChecks$DummyCheck3

src/main/resources/fxml/health_check_list.fxml

@@ -3,17 +3,18 @@
 <?import javafx.geometry.Insets?>
 <?import javafx.scene.control.Button?>
 <?import javafx.scene.control.ButtonBar?>
+<?import javafx.scene.control.CheckBox?>
 <?import javafx.scene.control.Label?>
 <?import javafx.scene.control.ListView?>
 <?import javafx.scene.layout.HBox?>
+<?import javafx.scene.layout.StackPane?>
 <?import javafx.scene.layout.VBox?>
 <?import java.lang.Integer?>
-<?import javafx.scene.layout.StackPane?>
-<?import javafx.scene.control.CheckBox?>
 <VBox xmlns:fx="http://javafx.com/fxml"
 	  xmlns="http://javafx.com/javafx"
 	  fx:controller="org.cryptomator.ui.health.CheckListController"
-	  minHeight="145"
+	  prefWidth="600"
+	  prefHeight="400"
 	  spacing="12">
 	<padding>
 		<Insets topRightBottomLeft="12"/>
@@ -28,7 +29,7 @@
 				<CheckBox onAction="#toggleSelectAll" text="%health.checkList.selectAllBox" visible="${!controller.showResultScreen}" managed="${!controller.showResultScreen}" />
 				<ListView fx:id="checksListView" VBox.vgrow="ALWAYS"/>
 			</VBox>
-			<StackPane visible="${controller.showResultScreen}" managed="${controller.showResultScreen}" HBox.hgrow="ALWAYS" >
+			<StackPane visible="${controller.showResultScreen}" HBox.hgrow="ALWAYS" >
 				<VBox minWidth="300" alignment="CENTER" visible="${!controller.anyCheckSelected}" managed="${!controller.anyCheckSelected}" >
 					<Label text="%health.check.detail.noSelectedCheck" wrapText="true" alignment="CENTER" />
 				</VBox>
@@ -39,7 +40,7 @@
 			<buttons>
 				<Button text="%generic.button.cancel" ButtonBar.buttonData="CANCEL_CLOSE" onAction="#cancelCheck" disable="${!controller.running}" visible="${controller.showResultScreen}" managed="${controller.showResultScreen}" />
 				<Button text="%health.check.exportBtn" ButtonBar.buttonData="NEXT_FORWARD" defaultButton="true" disable="${!controller.finished}" visible="${controller.showResultScreen}" managed="${controller.showResultScreen}" onAction="#exportResults"/>
-				<Button text="%health.check.runBatchBtn" ButtonBar.buttonData="NEXT_FORWARD" defaultButton="true" onAction="#runSelectedChecks" disable="${controller.numberOfPickedChecks == ZERO}" visible="${!controller.showResultScreen}" managed="${!controller.showResultScreen}"/>
+				<Button text="%health.check.runBatchBtn" ButtonBar.buttonData="NEXT_FORWARD" defaultButton="true" onAction="#runSelectedChecks" disable="${controller.chosenTaskCount == ZERO}" visible="${!controller.showResultScreen}" managed="${!controller.showResultScreen}"/>
 			</buttons>
 		</ButtonBar>
 	</children>

src/main/resources/fxml/health_result_listcell.fxml

@@ -6,6 +6,10 @@
 <?import javafx.scene.control.Label?>
 <?import javafx.scene.layout.HBox?>
 <?import javafx.scene.layout.Region?>
+<?import javafx.scene.control.ProgressIndicator?>
+<?import javafx.scene.text.Text?>
+<?import javafx.scene.layout.Pane?>
+<?import javafx.scene.layout.StackPane?>
 <HBox xmlns:fx="http://javafx.com/fxml"
 	  xmlns="http://javafx.com/javafx"
 	  fx:controller="org.cryptomator.ui.health.ResultListCellController"
@@ -18,12 +22,18 @@
 		<Insets topRightBottomLeft="6"/>
 	</padding>
 	<children>
-		<FontAwesome5IconView fx:id="iconView" HBox.hgrow="NEVER" glyphSize="16"/>
+		<FontAwesome5IconView fx:id="iconView" HBox.hgrow="NEVER" glyphSize="16" glyph="${controller.glyph}"/>
 		<Label text="${controller.description}"/>
 		<Region HBox.hgrow="ALWAYS"/>
 		<!-- TODO: setting the minWidth of the button is just a workaround.
 		           What we actually want to do is to prevent shrinking the button more than the text
 		           -> own subclass of HBox is needed -->
-		<Button fx:id="actionButton" text="%health.check.fixBtn" onAction="#runResultAction" alignment="CENTER" visible="false" minWidth="-Infinity"/>
+		<StackPane HBox.hgrow="NEVER">
+			<children>
+				<Button fx:id="fixButton" text="%health.check.fixBtn" visible="${controller.fixable}" managed="${controller.fixable}" onAction="#fix" alignment="CENTER" minWidth="-Infinity"/>
+				<ProgressIndicator progress="-1" prefWidth="12" prefHeight="12" visible="${controller.fixing}" managed="${controller.fixing}"/>
+				<FontAwesome5IconView glyph="CHECK" glyphSize="16" visible="${controller.fixed}" managed="${controller.fixed}"/>
+			</children>
+		</StackPane>
 	</children>
 </HBox>

src/main/resources/fxml/health_start.fxml

@@ -17,22 +17,25 @@
 		<Insets topRightBottomLeft="12"/>
 	</padding>
 	<children>
-
-		<!-- TODO: combine the two below labels to one and bind the properties accordingly or, preferably think about a new flow -->
-		<Label text="%health.start.configInvalid" visible="${controller.invalidConfig}" managed="${controller.invalidConfig}" wrapText="true" contentDisplay="LEFT">
+		<Label text="TODO loading config..." visible="${controller.loading}" managed="${controller.loading}" wrapText="true" contentDisplay="LEFT">
 			<graphic>
-				<FontAwesome5IconView glyph="TIMES" styleClass="glyph-icon-red" />
+				<FontAwesome5IconView glyph="SPINNER"/>
 			</graphic>
 		</Label>
-		<Label text="%health.start.configValid" visible="${!controller.invalidConfig}" managed="${!controller.invalidConfig}" wrapText="true" contentDisplay="LEFT">
+		<Label text="%health.start.configInvalid" visible="${controller.failed}" managed="${controller.failed}" wrapText="true" contentDisplay="LEFT">
 			<graphic>
-				<FontAwesome5IconView glyph="CHECK" styleClass="glyph-icon-primary" />
+				<FontAwesome5IconView glyph="TIMES" styleClass="glyph-icon-red"/>
+			</graphic>
+		</Label>
+		<Label text="%health.start.configValid" visible="${controller.loaded}" managed="${controller.loaded}" wrapText="true" contentDisplay="LEFT">
+			<graphic>
+				<FontAwesome5IconView glyph="CHECK" styleClass="glyph-icon-primary"/>
 			</graphic>
 		</Label>
 		<ButtonBar buttonMinWidth="120" buttonOrder="+CX">
 			<buttons>
 				<Button text="%generic.button.cancel" ButtonBar.buttonData="CANCEL_CLOSE" cancelButton="true" onAction="#close"/>
-				<Button text="%generic.button.next" ButtonBar.buttonData="NEXT_FORWARD" disable="${controller.invalidConfig}" defaultButton="true" onAction="#next"/>
+				<Button text="%generic.button.next" ButtonBar.buttonData="NEXT_FORWARD" disable="${!controller.loaded}" defaultButton="true" onAction="#next"/>
 			</buttons>
 		</ButtonBar>
 	</children>