Add a mechanism to pause and resume geolocation requests.

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

+// Copyright 2012 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.content.Context;
+
+import com.google.common.annotations.VisibleForTesting;
+
+import org.chromium.base.CalledByNative;
+import org.chromium.base.ThreadUtils;
+
+import java.util.concurrent.FutureTask;
+
+/**
+ * Implements the Java side of LocationProviderAndroid.
+ * Delegates all real functionality to the implementation
+ * returned from LocationProviderFactory.
+ * See detailed documentation on
+ * content/browser/geolocation/android_location_api_adapter.h.
+ * Based on android.webkit.GeolocationService.java
+ */
+@VisibleForTesting
+public class LocationProviderAdapter {
+
+    // Delegate handling the real work in the main thread.
+    private LocationProviderFactory.LocationProvider mImpl;
+
+    private LocationProviderAdapter(Context context) {
+        mImpl = LocationProviderFactory.get(context);
+    }
+
+    @CalledByNative
+    static LocationProviderAdapter create(Context context) {
+        return new LocationProviderAdapter(context);
+    }
+
+    /**
+     * Start listening for location updates until we're told to quit. May be
+     * called in any thread.
+     * @param gpsEnabled Whether or not we're interested in high accuracy GPS.
+     */
+    @CalledByNative
+    public boolean start(final boolean gpsEnabled) {
+        FutureTask<Void> task = new FutureTask<Void>(new Runnable() {
+            @Override
+            public void run() {
+                mImpl.start(gpsEnabled);
+            }
+        }, null);
+        ThreadUtils.runOnUiThread(task);
+        return true;
+    }
+
+    /**
+     * Stop listening for location updates. May be called in any thread.
+     */
+    @CalledByNative
+    public void stop() {
+        FutureTask<Void> task = new FutureTask<Void>(new Runnable() {
+            @Override
+            public void run() {
+                mImpl.stop();
+            }
+        }, null);
+        ThreadUtils.runOnUiThread(task);
+    }
+
+    /**
+     * Returns true if we are currently listening for location updates, false if not.
+     * Must be called only in the UI thread.
+     */
+    public boolean isRunning() {
+        assert ThreadUtils.runningOnUiThread();
+        return mImpl.isRunning();
+    }
+
+    public static void newLocationAvailable(double latitude, double longitude, double timestamp,
+            boolean hasAltitude, double altitude,
+            boolean hasAccuracy, double accuracy,
+            boolean hasHeading, double heading,
+            boolean hasSpeed, double speed) {
+        nativeNewLocationAvailable(latitude, longitude, timestamp, hasAltitude, altitude,
+                hasAccuracy, accuracy, hasHeading, heading, hasSpeed, speed);
+    }
+
+    public static void newErrorAvailable(String message) {
+        nativeNewErrorAvailable(message);
+    }
+
+    // Native functions
+    private static native void nativeNewLocationAvailable(
+            double latitude, double longitude, double timeStamp,
+            boolean hasAltitude, double altitude,
+            boolean hasAccuracy, double accuracy,
+            boolean hasHeading, double heading,
+            boolean hasSpeed, double speed);
+    private static native void nativeNewErrorAvailable(String message);
+}