SyntheticGestureTarget implementation for injecting synthetic input events

content/public/android/java/src/org/chromium/content/browser/TouchEventSynthesizer.java

Index: content/public/android/java/src/org/chromium/content/browser/TouchEventSynthesizer.java
diff --git a/content/public/android/java/src/org/chromium/content/browser/TouchEventSynthesizer.java b/content/public/android/java/src/org/chromium/content/browser/TouchEventSynthesizer.java
new file mode 100644
index 0000000000000000000000000000000000000000..9c67587e96559ed752b9e836621d4023d0764963
--- /dev/null
+++ b/content/public/android/java/src/org/chromium/content/browser/TouchEventSynthesizer.java
@@ -0,0 +1,118 @@
+// Copyright 2013 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.content.browser;
+
+import android.os.SystemClock;
+import android.view.MotionEvent;
+import android.view.MotionEvent.PointerProperties;
+import android.view.MotionEvent.PointerCoords;
+
+import org.chromium.base.CalledByNative;
+import org.chromium.base.JNINamespace;
+
+/**
+ * Provides a Java-side implementation for injecting synthetic touch events.
+ */
+@JNINamespace("content")
+public class TouchEventSynthesizer {
+    private static final int MAX_NUM_POINTERS = 16;
+
+    private static final int ACTION_START = 0;
+    private static final int ACTION_MOVE = 1;
+    private static final int ACTION_CANCEL = 2;
+    private static final int ACTION_END = 3;
+
+    private final ContentViewCore mContentViewCore;
+    private final PointerProperties[] mPointerProperties;
+    private final PointerCoords[] mPointerCoords;
+    private long mDownTime;
+
+    TouchEventSynthesizer(ContentViewCore contentViewCore) {
+        mContentViewCore = contentViewCore;
+        mPointerProperties = new PointerProperties[MAX_NUM_POINTERS];
+        mPointerCoords = new PointerCoords[MAX_NUM_POINTERS];
+    }
+
+    @CalledByNative
+    void setPointer(int index, int x, int y, int id) {
+        assert (0 <= index && index < MAX_NUM_POINTERS);
+
+        // Convert coordinates from density independent pixels to density dependent pixels.
+        float scaleFactor = mContentViewCore.getRenderCoordinates().getDeviceScaleFactor();
+
+        PointerCoords coords = new PointerCoords();
+        coords.x = scaleFactor * x;
+        coords.y = scaleFactor * y;
+        coords.pressure = 1.0f;
+        mPointerCoords[index] = coords;
+
+        PointerProperties properties = new PointerProperties();
+        properties.id = id;
+        mPointerProperties[index] = properties;
+    }
+
+    @CalledByNative
+    void inject(int action, int pointerCount) {
+        long time = SystemClock.uptimeMillis();
+
+        switch (action) {
+            case ACTION_START: {
+                mDownTime = time;
+                MotionEvent event = MotionEvent.obtain(
+                        mDownTime, time, MotionEvent.ACTION_DOWN, 1,
+                        mPointerProperties, mPointerCoords,
+                        0, 0, 1, 1, 0, 0, 0, 0);
+                mContentViewCore.onTouchEvent(event);
+                event.recycle();
+
+                if (pointerCount > 1) {
+                    event = MotionEvent.obtain(
+                            mDownTime, time, MotionEvent.ACTION_POINTER_DOWN,
+                            pointerCount, mPointerProperties, mPointerCoords,
+                            0, 0, 1, 1, 0, 0, 0, 0);
+                    mContentViewCore.onTouchEvent(event);
+                    event.recycle();
+                }
+                break;
+            }
+            case ACTION_MOVE: {
+                MotionEvent event = MotionEvent.obtain(mDownTime, time,
+                        MotionEvent.ACTION_MOVE,
+                        pointerCount, mPointerProperties, mPointerCoords,
+                        0, 0, 1, 1, 0, 0, 0, 0);
+                mContentViewCore.onTouchEvent(event);
+                event.recycle();
+                break;
+            }
+            case ACTION_CANCEL: {
+                MotionEvent event = MotionEvent.obtain(
+                        mDownTime, time, MotionEvent.ACTION_CANCEL, 1,
+                        mPointerProperties, mPointerCoords,
+                        0, 0, 1, 1, 0, 0, 0, 0);
+                mContentViewCore.onTouchEvent(event);
+                event.recycle();
+                break;
+            }
+            case ACTION_END: {
+                if (pointerCount > 1) {
+                    MotionEvent event = MotionEvent.obtain(
+                        mDownTime, time, MotionEvent.ACTION_POINTER_UP,
+                        pointerCount, mPointerProperties, mPointerCoords,
+                        0, 0, 1, 1, 0, 0, 0, 0);
+                    mContentViewCore.onTouchEvent(event);
+                    event.recycle();
+                }
+
+                MotionEvent event = MotionEvent.obtain(
+                        mDownTime, time, MotionEvent.ACTION_UP, 1,
+                        mPointerProperties, mPointerCoords,
+                        0, 0, 1, 1, 0, 0, 0, 0);
+                mContentViewCore.onTouchEvent(event);
+                event.recycle();
+                break;
+            }
+        }
+    }
+}