Pointer/hover media query support: platform-dependent changes

ui/android/java/src/org/chromium/ui/base/TouchDevice.java

 // Copyright 2014 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.ui.base;
 
 import android.content.Context;
 import android.content.pm.PackageManager;
+import android.view.InputDevice;
 
 import org.chromium.base.CalledByNative;
 import org.chromium.base.JNINamespace;
 
 /**
  * Simple proxy to let us query the touch device from C++
  */
 @JNINamespace("ui")
 public class TouchDevice {

[bokan, 2014/11/03 14:28:11]

Can we change the name of this class? Perhaps InputDevice? We're doing more than
just touchscreen here now. (Not necessarily in this CL)

[mustaq, 2014/11/03 17:11:38]

I agree InputDevice is a better name here, will add a TODO.

Note that it could be overkill because this class is directly associated with
ui/base/touch/touch_device*, and we should then rename the whole tree on the c++
side!

 
     /**
      * Static methods only so make constructor private.
      */
     private TouchDevice() { }
 
     /**
-     * Returns the number of supported touch points.
-     *
      * @return Maximum supported touch points.
      */
     @CalledByNative
     private static int maxTouchPoints(Context context) {
         // Android only tells us if the device belongs to a "Touchscreen Class"
         // which only guarantees a minimum number of touch points. Be
         // conservative and return the minimum, checking membership from the
         // highest class down.
+
         if (context.getPackageManager().hasSystemFeature(
                 PackageManager.FEATURE_TOUCHSCREEN_MULTITOUCH_JAZZHAND)) {
             return 5;
         } else if (context.getPackageManager().hasSystemFeature(
                 PackageManager.FEATURE_TOUCHSCREEN_MULTITOUCH_DISTINCT)) {
             return 2;
         } else if (context.getPackageManager().hasSystemFeature(
                 PackageManager.FEATURE_TOUCHSCREEN_MULTITOUCH)) {
             return 2;
         } else if (context.getPackageManager().hasSystemFeature(
                 PackageManager.FEATURE_TOUCHSCREEN)) {
             return 1;
         } else {
             return 0;
         }
     }
+
+    /**
+     * TODO
+     */
+    public enum PointerType {
+        None(1), Coarse(2), Fine(4);
+
+        private int mValue;
+
+        private PointerType(int value) {
+            mValue = value;
+        }
+
+        public int getValue() {
+            return mValue;
+        }
+    }
+
+    /**
+     * @return TODO
+     */
+    @CalledByNative
+    private static int availablePointerTypes(Context context) {
+        int pointerTypesVal = 0;
+
+        for (int deviceId : InputDevice.getDeviceIds()) {
+            int sources = InputDevice.getDevice(deviceId).getSources();
+
+            if (hasSource(sources, InputDevice.SOURCE_JOYSTICK)

[bokan, 2014/11/03 14:28:10]

Is there a cursor associated with a joystick? I've never seen a joystick
interface use a cursor, to me this would be a pointer: none device.

[mustaq, 2014/11/03 17:11:38]

I was considering an old PC-based game I played long ago. Will fix.

+                    || hasSource(sources, InputDevice.SOURCE_MOUSE)
+                    || hasSource(sources, InputDevice.SOURCE_STYLUS)
+                    || hasSource(sources, InputDevice.SOURCE_TRACKBALL)) {
+                pointerTypesVal |= PointerType.Fine.getValue();
+
+            } else if (hasSource(sources, InputDevice.SOURCE_CLASS_POINTER)) {
+                pointerTypesVal |= PointerType.Coarse.getValue();
+
+            }
+        }
+
+        return pointerTypesVal;
+    }
+
+    private static boolean hasSource(int sources, int inputDeviceSource) {
+        return (sources & inputDeviceSource) == inputDeviceSource;
+    }
 }