Adding a wrapper class over InputConsumer to use it in Launcher

This allows us to use platform logic for event deduping and
timestamp extrapolation (eg using velocity tracker on the main tread).


Test: Tested the library with launcher
Change-Id: Ic4544aab975db1447100618ad2cb66b0d6c19134

1 files changed, 113 insertions, 0 deletions

diff --git a/packages/SystemUI/shared/src/com/android/systemui/shared/system/InputChannelCompat.java b/packages/SystemUI/shared/src/com/android/systemui/shared/system/InputChannelCompat.java
new file mode 100644
index 000000000000..f7ccb816b675
--- /dev/null
+++ b/packages/SystemUI/shared/src/com/android/systemui/shared/system/InputChannelCompat.java
@@ -0,0 +1,113 @@
+/**
+ * Copyright (C) 2019 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 com.android.systemui.shared.system;
+
+import android.os.Looper;
+import android.util.Pair;
+import android.view.BatchedInputEventReceiver;
+import android.view.Choreographer;
+import android.view.InputChannel;
+import android.view.InputEvent;
+import android.view.InputEventSender;
+
+/**
+ * @see android.view.InputChannel
+ */
+public class InputChannelCompat {
+
+    /**
+     * Callback for receiving event callbacks
+     */
+    public interface InputEventListener {
+        /**
+         * @param ev event to be handled
+         */
+        void onInputEvent(InputEvent ev);
+    }
+
+    /**
+     * Creates a dispatcher and receiver pair to better handle events across threads.
+     */
+    public static Pair<InputEventDispatcher, InputEventReceiver> createPair(String name,
+            Looper looper, Choreographer choreographer, InputEventListener listener) {
+        InputChannel[] channels = InputChannel.openInputChannelPair(name);
+
+        InputEventDispatcher dispatcher = new InputEventDispatcher(channels[0], looper);
+        InputEventReceiver receiver = new InputEventReceiver(channels[1], looper, choreographer,
+                listener);
+        return Pair.create(dispatcher, receiver);
+    }
+
+    /**
+     * @see BatchedInputEventReceiver
+     */
+    public static class InputEventReceiver {
+
+        private final BatchedInputEventReceiver mReceiver;
+        private final InputChannel mInputChannel;
+
+        public InputEventReceiver(InputChannel inputChannel, Looper looper,
+                Choreographer choreographer, final InputEventListener listener) {
+            mInputChannel = inputChannel;
+            mReceiver = new BatchedInputEventReceiver(inputChannel, looper, choreographer) {
+
+                @Override
+                public void onInputEvent(InputEvent event) {
+                    listener.onInputEvent(event);
+                    finishInputEvent(event, true /* handled */);
+                }
+            };
+        }
+
+        /**
+         * @see BatchedInputEventReceiver#dispose()
+         */
+        public void dispose() {
+            mReceiver.dispose();
+            mInputChannel.dispose();
+        }
+    }
+
+    /**
+     * @see InputEventSender
+     */
+    public static class InputEventDispatcher {
+
+        private final InputChannel mInputChannel;
+        private final InputEventSender mSender;
+
+        private InputEventDispatcher(InputChannel inputChannel, Looper looper) {
+            mInputChannel = inputChannel;
+            mSender = new InputEventSender(inputChannel, looper) { };
+        }
+
+        /**
+         * @see InputEventSender#sendInputEvent(int, InputEvent)
+         */
+        public void dispatch(InputEvent ev) {
+            mSender.sendInputEvent(ev.getSequenceNumber(), ev);
+        }
+
+        /**
+         * @see InputEventSender#dispose()
+         */
+        public void dispose() {
+            mSender.dispose();
+            mInputChannel.dispose();
+        }
+    }
+}