Added patched recyclerview-selection 1.0.0

app/src/main/java/androidx/recyclerview/selection/MutableSelection.java

@@ -0,0 +1,76 @@
+/*
+ * Copyright 2017 The Android Open Source Project
+ *
+ * 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 androidx.recyclerview.selection;
+
+import androidx.annotation.NonNull;
+
+/**
+ * Subclass of {@link Selection} exposing public support for mutating the underlying
+ * selection data. This is useful for clients of {@link SelectionTracker} that wish to
+ * manipulate a copy of selection data obtained via
+ * {@link SelectionTracker#copySelection(MutableSelection)}.
+ *
+ * <p>
+ * While the {@link Selection} class is not intrinsically immutable, it is not mutable
+ * by non-library code. Furthermore the value returned from {@link SelectionTracker#getSelection()}
+ * is a live view of the underlying selection, mutable by the library itself.
+ *
+ * <p>
+ * {@link MutableSelection} allows clients to obtain a mutable copy of the Selection
+ * state held by the selection library. This is useful in situations where a stable
+ * snapshot of the selection is required.
+ *
+ *
+ * <p><b>Example</b>
+ *
+ * <p>
+ * <pre>
+ * MutableSelection snapshot = new MutableSelection();
+ * selectionTracker.copySelection(snapshot);
+ *
+ * // Clear the user visible selection.
+ * selectionTracker.clearSelection();
+ * // tracker.getSelection().isEmpty() will be true.
+ * // shapshot has a copy of the previous selection.
+ * </pre>
+ *
+ * @see android.text.Selection
+ *
+ * @param <K> Selection key type. @see {@link StorageStrategy} for supported types.
+ */
+public final class MutableSelection<K> extends Selection<K> {
+
+    @Override
+    public boolean add(@NonNull K key) {
+        return super.add(key);
+    }
+
+    @Override
+    public boolean remove(@NonNull K key) {
+        return super.remove(key);
+    }
+
+    @Override
+    public void copyFrom(@NonNull Selection<K> source) {
+        super.copyFrom(source);
+    }
+
+    @Override
+    public void clear() {
+        super.clear();
+    }
+}