Moved isComponentVisible to separate interface (#10303)

HasComponents.isComponentVisible is now SelectiveRenderer.isRendered

Change-Id: Ic3b9cd65278ffc2a38ee20c76ec771ee057268bf

1 files changed, 50 insertions, 0 deletions

diff --git a/server/src/com/vaadin/ui/SelectiveRenderer.java b/server/src/com/vaadin/ui/SelectiveRenderer.java
new file mode 100644
index 0000000000..47fd9bf0ee
--- /dev/null
+++ b/server/src/com/vaadin/ui/SelectiveRenderer.java
@@ -0,0 +1,50 @@
+/*
+ * Copyright 2011 Vaadin Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"); you may not
+ * use this file except in compliance with the License. You may obtain a copy of
+ * the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+ * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+ * License for the specific language governing permissions and limitations under
+ * the License.
+ */
+package com.vaadin.ui;
+
+/**
+ * Interface implemented by {@link HasComponents} implementors that wish to
+ * dynamically be able to prevent given child components from reaching the
+ * client side.
+ * 
+ * @author Vaadin Ltd
+ * @version @VERSION@
+ * @since 7.0
+ * 
+ */
+public interface SelectiveRenderer extends HasComponents {
+    /**
+     * Checks if the child component should be rendered (sent to the client
+     * side). This method allows hiding a child component from updates and
+     * communication to and from the client. It is mostly useful for parents
+     * which show only a limited number of their children at any given time and
+     * want to allow updates only for the visible children (e.g. TabSheet has
+     * one tab open at a time).
+     * <p>
+     * This method can only prevent updates from reaching the client, not force
+     * child components to reach the client. If the child is set to visible,
+     * returning false will prevent the child from being sent to the client. If
+     * a child is set to invisible, this method has no effect.
+     * </p>
+     * 
+     * @param childComponent
+     *            The child component to check
+     * @return true if the child component may be sent to the client, false
+     *         otherwise
+     */
+    public boolean isRendered(Component childComponent);
+
+}