Support addCloseListener for Notification (#10027)

Converts Notification to an Extension and adds support for listening to the closing of notifications.

Fixes #888

4 files changed, 173 insertions, 124 deletions

diff --git a/server/src/main/java/com/vaadin/server/Page.java b/server/src/main/java/com/vaadin/server/Page.java
index 3e95de0c4b..d458839e4c 100644
--- a/server/src/main/java/com/vaadin/server/Page.java
+++ b/server/src/main/java/com/vaadin/server/Page.java
@@ -311,12 +311,6 @@ public class Page implements Serializable {
     private final LinkedList<OpenResource> openList = new LinkedList<>();
 
     /**
-     * A list of notifications that are waiting to be sent to the client.
-     * Cleared (set to null) when the notifications have been sent.
-     */
-    private List<Notification> notifications;
-
-    /**
      * Event fired when the URI fragment of a <code>Page</code> changes.
      *
      * @see Page#addUriFragmentChangedListener(UriFragmentChangedListener)
@@ -937,45 +931,6 @@ public class Page implements Serializable {
             openList.clear();
         }
 
-        // Paint notifications
-        if (notifications != null) {
-            target.startTag("notifications");
-            for (final Notification n : notifications) {
-                target.startTag("notification");
-                if (n.getCaption() != null) {
-                    target.addAttribute(
-                            UIConstants.ATTRIBUTE_NOTIFICATION_CAPTION,
-                            n.getCaption());
-                }
-                if (n.getDescription() != null) {
-                    target.addAttribute(
-                            UIConstants.ATTRIBUTE_NOTIFICATION_MESSAGE,
-                            n.getDescription());
-                }
-                if (n.getIcon() != null) {
-                    target.addAttribute(UIConstants.ATTRIBUTE_NOTIFICATION_ICON,
-                            n.getIcon());
-                }
-                if (!n.isHtmlContentAllowed()) {
-                    target.addAttribute(
-                            UIConstants.NOTIFICATION_HTML_CONTENT_NOT_ALLOWED,
-                            true);
-                }
-                target.addAttribute(UIConstants.ATTRIBUTE_NOTIFICATION_POSITION,
-                        n.getPosition().ordinal());
-                target.addAttribute(UIConstants.ATTRIBUTE_NOTIFICATION_DELAY,
-                        n.getDelayMsec());
-                if (n.getStyleName() != null) {
-                    target.addAttribute(
-                            UIConstants.ATTRIBUTE_NOTIFICATION_STYLE,
-                            n.getStyleName());
-                }
-                target.endTag("notification");
-            }
-            target.endTag("notifications");
-            notifications = null;
-        }
-
         if (newPushState != null) {
             target.addAttribute(UIConstants.ATTRIBUTE_PUSH_STATE, newPushState);
             newPushState = null;
@@ -1342,20 +1297,6 @@ public class Page implements Serializable {
     }
 
     /**
-     * Internal helper method to actually add a notification.
-     *
-     * @param notification
-     *            the notification to add
-     */
-    private void addNotification(Notification notification) {
-        if (notifications == null) {
-            notifications = new LinkedList<>();
-        }
-        notifications.add(notification);
-        uI.markAsDirty();
-    }
-
-    /**
      * Shows a notification message.
      *
      * @see Notification
@@ -1367,7 +1308,7 @@ public class Page implements Serializable {
      */
     @Deprecated
     public void showNotification(Notification notification) {
-        addNotification(notification);
+        notification.show(this);
     }
 
     /**
@@ -1469,11 +1410,22 @@ public class Page implements Serializable {
      * @since 8.1
      */
     public Collection<Dependency> getPendingDependencies() {
-        ArrayList<Dependency> copy = new ArrayList<>();
+        List<Dependency> copy = new ArrayList<>();
         if (pendingDependencies != null) {
             copy.addAll(pendingDependencies);
         }
         pendingDependencies = null;
         return copy;
     }
+
+    /**
+     * Returns the {@link UI} of this {@link Page}.
+     *
+     * @return the {@link UI} of this {@link Page}.
+     *
+     * @since
+     */
+    public UI getUI() {
+        return uI;
+    }
 }
diff --git a/server/src/main/java/com/vaadin/server/PaintTarget.java b/server/src/main/java/com/vaadin/server/PaintTarget.java
index 6d531abc2c..0719fb26aa 100644
--- a/server/src/main/java/com/vaadin/server/PaintTarget.java
+++ b/server/src/main/java/com/vaadin/server/PaintTarget.java
@@ -39,7 +39,7 @@ public interface PaintTarget extends Serializable {
      * @param sectionTagName
      *            the name of the tag.
      * @param sectionData
-     *            the scetion data.
+     *            the section data.
      * @throws PaintException
      *             if the paint operation failed.
      */
@@ -145,7 +145,7 @@ public interface PaintTarget extends Serializable {
     public void endTag(String tagName) throws PaintException;
 
     /**
-     * Adds a boolean attribute to component. Atributes must be added before any
+     * Adds a boolean attribute to component. Attributes must be added before any
      * content is written.
      *
      * @param name
@@ -159,7 +159,7 @@ public interface PaintTarget extends Serializable {
     public void addAttribute(String name, boolean value) throws PaintException;
 
     /**
-     * Adds a integer attribute to component. Atributes must be added before any
+     * Adds a integer attribute to component. Attributes must be added before any
      * content is written.
      *
      * @param name
@@ -173,7 +173,7 @@ public interface PaintTarget extends Serializable {
     public void addAttribute(String name, int value) throws PaintException;
 
     /**
-     * Adds a resource attribute to component. Atributes must be added before
+     * Adds a resource attribute to component. Attributes must be added before
      * any content is written.
      *
      * @param name
@@ -222,7 +222,7 @@ public interface PaintTarget extends Serializable {
             StreamVariable value) throws PaintException;
 
     /**
-     * Adds a long attribute to component. Atributes must be added before any
+     * Adds a long attribute to component. Attributes must be added before any
      * content is written.
      *
      * @param name
@@ -236,7 +236,7 @@ public interface PaintTarget extends Serializable {
     public void addAttribute(String name, long value) throws PaintException;
 
     /**
-     * Adds a float attribute to component. Atributes must be added before any
+     * Adds a float attribute to component. Attributes must be added before any
      * content is written.
      *
      * @param name
@@ -250,7 +250,7 @@ public interface PaintTarget extends Serializable {
     public void addAttribute(String name, float value) throws PaintException;
 
     /**
-     * Adds a double attribute to component. Atributes must be added before any
+     * Adds a double attribute to component. Attributes must be added before any
      * content is written.
      *
      * @param name
@@ -264,7 +264,7 @@ public interface PaintTarget extends Serializable {
     public void addAttribute(String name, double value) throws PaintException;
 
     /**
-     * Adds a string attribute to component. Atributes must be added before any
+     * Adds a string attribute to component. Attributes must be added before any
      * content is written.
      *
      * @param name
@@ -318,7 +318,7 @@ public interface PaintTarget extends Serializable {
             throws PaintException;
 
     /**
-     * Adds a int type variable.
+     * Adds an int type variable.
      *
      * @param owner
      *            the Listener for variable changes.
@@ -434,7 +434,7 @@ public interface PaintTarget extends Serializable {
             throws PaintException;
 
     /**
-     * Adds a upload stream type variable.
+     * Adds an upload stream type variable.
      *
      * @param owner
      *            the Listener for variable changes.
diff --git a/server/src/main/java/com/vaadin/ui/Notification.java b/server/src/main/java/com/vaadin/ui/Notification.java
index 9ec031799f..15637ef3b0 100644
--- a/server/src/main/java/com/vaadin/ui/Notification.java
+++ b/server/src/main/java/com/vaadin/ui/Notification.java
@@ -17,10 +17,17 @@
 package com.vaadin.ui;
 
 import java.io.Serializable;
+import java.lang.reflect.Method;
 
+import com.vaadin.event.ConnectorEvent;
+import com.vaadin.server.AbstractExtension;
 import com.vaadin.server.Page;
 import com.vaadin.server.Resource;
+import com.vaadin.server.ResourceReference;
 import com.vaadin.shared.Position;
+import com.vaadin.shared.Registration;
+import com.vaadin.shared.ui.notification.NotificationServerRpc;
+import com.vaadin.shared.ui.notification.NotificationState;
 
 /**
  * A notification message, used to display temporary messages to the user - for
@@ -61,7 +68,15 @@ import com.vaadin.shared.Position;
  * </p>
  *
  */
-public class Notification implements Serializable {
+public class Notification extends AbstractExtension implements Serializable {
+
+    /**
+     * The server RPC.
+     */
+    protected NotificationServerRpc rpc = () -> {
+        fireEvent(new CloseEvent(Notification.this));
+    };
+
     public enum Type {
         HUMANIZED_MESSAGE("humanized"), WARNING_MESSAGE(
                 "warning"), ERROR_MESSAGE("error"), TRAY_NOTIFICATION("tray"),
@@ -113,14 +128,6 @@ public class Notification implements Serializable {
     public static final int DELAY_FOREVER = -1;
     public static final int DELAY_NONE = 0;
 
-    private String caption;
-    private String description;
-    private Resource icon;
-    private Position position = Position.MIDDLE_CENTER;
-    private int delayMsec = 0;
-    private String styleName;
-    private boolean htmlContentAllowed;
-
     /**
      * Creates a "humanized" notification message.
      *
@@ -199,28 +206,29 @@ public class Notification implements Serializable {
      */
     public Notification(String caption, String description, Type type,
             boolean htmlContentAllowed) {
-        this.caption = caption;
-        this.description = description;
-        this.htmlContentAllowed = htmlContentAllowed;
+        registerRpc(rpc);
+        setCaption(caption);
+        setDescription(description);
+        setHtmlContentAllowed(htmlContentAllowed);
         setType(type);
     }
 
     private void setType(Type type) {
-        styleName = type.getStyle();
+        setStyleName(type.getStyle());
         switch (type) {
         case WARNING_MESSAGE:
-            delayMsec = 1500;
+            setDelayMsec(1500);
             break;
         case ERROR_MESSAGE:
-            delayMsec = -1;
+            setDelayMsec(DELAY_FOREVER);
             break;
         case TRAY_NOTIFICATION:
-            delayMsec = 3000;
-            position = Position.BOTTOM_RIGHT;
+            setDelayMsec(3000);
+            setPosition(Position.BOTTOM_RIGHT);
             break;
         case ASSISTIVE_NOTIFICATION:
-            delayMsec = 3000;
-            position = Position.ASSISTIVE;
+            setDelayMsec(3000);
+            setPosition(Position.ASSISTIVE);
             break;
         case HUMANIZED_MESSAGE:
         default:
@@ -234,35 +242,36 @@ public class Notification implements Serializable {
      * @return The message caption
      */
     public String getCaption() {
-        return caption;
+        return getState(false).caption;
     }
 
     /**
-     * Sets the caption part of the notification message
+     * Sets the caption part of the notification message.
      *
      * @param caption
      *            The message caption
      */
     public void setCaption(String caption) {
-        this.caption = caption;
+        getState().caption = caption;
     }
 
     /**
      * Gets the description part of the notification message.
      *
-     * @return The message description.
+     * @return The message description
      */
     public String getDescription() {
-        return description;
+        return getState(false).description;
     }
 
     /**
      * Sets the description part of the notification message.
      *
      * @param description
+     *            The message description
      */
     public void setDescription(String description) {
-        this.description = description;
+        getState().description = description;
     }
 
     /**
@@ -271,17 +280,21 @@ public class Notification implements Serializable {
      * @return The position
      */
     public Position getPosition() {
-        return position;
+        return getState(false).position;
     }
 
     /**
      * Sets the position of the notification message.
      *
      * @param position
-     *            The desired notification position
+     *            The desired notification position,
+     *            not {@code null}
      */
     public void setPosition(Position position) {
-        this.position = position;
+        if (position == null) {
+            throw new IllegalArgumentException("Position can not be null");
+        }
+        getState().position = position;
     }
 
     /**
@@ -290,7 +303,7 @@ public class Notification implements Serializable {
      * @return The message icon
      */
     public Resource getIcon() {
-        return icon;
+        return getResource("icon");
     }
 
     /**
@@ -300,46 +313,47 @@ public class Notification implements Serializable {
      *            The desired message icon
      */
     public void setIcon(Resource icon) {
-        this.icon = icon;
+        setResource("icon", icon);
     }
 
     /**
      * Gets the delay before the notification disappears.
      *
-     * @return the delay in msec, -1 indicates the message has to be clicked.
+     * @return the delay in milliseconds, {@value #DELAY_FOREVER}
+     *            indicates the message has to be clicked.
      */
     public int getDelayMsec() {
-        return delayMsec;
+        return getState(false).delay;
     }
 
     /**
      * Sets the delay before the notification disappears.
      *
      * @param delayMsec
-     *            the desired delay in msec, -1 to require the user to click the
-     *            message
+     *            the desired delay in milliseconds, {@value #DELAY_FOREVER}
+     *            to require the user to click the message
      */
     public void setDelayMsec(int delayMsec) {
-        this.delayMsec = delayMsec;
+        getState().delay = delayMsec;
     }
 
     /**
      * Sets the style name for the notification message.
      *
      * @param styleName
-     *            The desired style name.
+     *            The desired style name
      */
     public void setStyleName(String styleName) {
-        this.styleName = styleName;
+        getState().styleName = styleName;
     }
 
     /**
      * Gets the style name for the notification message.
      *
-     * @return
+     * @return The style name
      */
     public String getStyleName() {
-        return styleName;
+        return getState(false).styleName;
     }
 
     /**
@@ -353,18 +367,19 @@ public class Notification implements Serializable {
      *            text
      */
     public void setHtmlContentAllowed(boolean htmlContentAllowed) {
-        this.htmlContentAllowed = htmlContentAllowed;
+        getState().htmlContentAllowed = htmlContentAllowed;
     }
 
     /**
-     * Checks whether caption and description are interpreted as html or plain
+     * Checks whether caption and description are interpreted as HTML or plain
      * text.
      *
-     * @return true if the texts are used as html, false if used as plain text
+     * @return {@code true} if the texts are used as HTML,
+     *         {@code false} if used as plain text
      * @see #setHtmlContentAllowed(boolean)
      */
     public boolean isHtmlContentAllowed() {
-        return htmlContentAllowed;
+        return getState(false).htmlContentAllowed;
     }
 
     /**
@@ -374,8 +389,17 @@ public class Notification implements Serializable {
      *            The page on which the notification should be shown
      */
     public void show(Page page) {
-        // TODO Can avoid deprecated API when Notification extends Extension
-        page.showNotification(this);
+        extend(page.getUI());
+    }
+
+    @Override
+    protected NotificationState getState() {
+        return (NotificationState) super.getState();
+    }
+
+    @Override
+    protected NotificationState getState(boolean markAsDirty) {
+        return (NotificationState) super.getState(markAsDirty);
     }
 
     /**
@@ -389,16 +413,20 @@ public class Notification implements Serializable {
      *
      * @param caption
      *            The message
+     * @return
+     *            The Notification
      */
-    public static void show(String caption) {
-        new Notification(caption).show(Page.getCurrent());
+    public static Notification show(String caption) {
+        Notification notification = new Notification(caption);
+        notification.extend(UI.getCurrent());
+        return notification;
     }
 
     /**
      * Shows a notification message the current page. The position and behavior
      * of the message depends on the type, which is one of the basic types
      * defined in {@link Notification}, for instance
-     * Notification.TYPE_WARNING_MESSAGE.
+     * {@link Type#WARNING_MESSAGE}.
      *
      * The caption is rendered as plain text with HTML automatically escaped.
      *
@@ -409,9 +437,13 @@ public class Notification implements Serializable {
      *            The message
      * @param type
      *            The message type
+     * @return
+     *            The Notification
      */
-    public static void show(String caption, Type type) {
-        new Notification(caption, type).show(Page.getCurrent());
+    public static Notification show(String caption, Type type) {
+        Notification notification = new Notification(caption, type);
+        notification.extend(UI.getCurrent());
+        return notification;
     }
 
     /**
@@ -431,8 +463,73 @@ public class Notification implements Serializable {
      *            The message description
      * @param type
      *            The message type
+     * @return
+     *            The Notification
      */
-    public static void show(String caption, String description, Type type) {
-        new Notification(caption, description, type).show(Page.getCurrent());
+    public static Notification show(String caption, String description, Type type) {
+        Notification notification = new Notification(caption, description, type);
+        notification.extend(UI.getCurrent());
+        return notification;
     }
+
+    /**
+     * Adds a CloseListener to the Notification.
+     *
+     * @param listener
+     *            the CloseListener to add, not {@code null}
+     * @since
+     */
+    public Registration addCloseListener(CloseListener listener) {
+        return addListener(CloseEvent.class, listener, CLOSE_METHOD);
+    }
+
+    private static final Method CLOSE_METHOD;
+    static {
+        try {
+            CLOSE_METHOD = CloseListener.class
+                    .getDeclaredMethod("notificationClose", CloseEvent.class);
+        } catch (final NoSuchMethodException e) {
+            // This should never happen
+            throw new RuntimeException(
+                    "Internal error, notification close method not found");
+        }
+    }
+
+    public static class CloseEvent extends ConnectorEvent {
+
+        /**
+         * @param source
+         */
+        public CloseEvent(Notification source) {
+            super(source);
+        }
+
+        /**
+         * Gets the Notification.
+         *
+         * @return The Notification
+         */
+        public Notification getNotification() {
+            return (Notification) getSource();
+        }
+    }
+
+    /**
+     * An interface used for listening to Notification close events. Add the
+     * CloseListener to a Notification and
+     * {@link CloseListener#notificationClose(CloseEvent)} will be called whenever the
+     * Notification is closed.
+     */
+    @FunctionalInterface
+    public interface CloseListener extends Serializable {
+        /**
+         * Use {@link CloseEvent#getNotification()} to get a reference to the
+         * {@link Notification} that was closed.
+         *
+         * @param e
+         *            The triggered event
+         */
+        public void notificationClose(CloseEvent e);
+    }
+
 }
diff --git a/server/src/main/java/com/vaadin/ui/Window.java b/server/src/main/java/com/vaadin/ui/Window.java
index 5a9b19f421..cd0840e517 100644
--- a/server/src/main/java/com/vaadin/ui/Window.java
+++ b/server/src/main/java/com/vaadin/ui/Window.java
@@ -504,7 +504,7 @@ public class Window extends Panel
          * {@link Window} that was closed.
          *
          * @param e
-         *            Event containing
+         *            The triggered event
          */
         public void windowClose(CloseEvent e);
     }