FaviconHelper.java revision f2477e01787aa58f445919b809d89e252beef54f 
1// Copyright 2013 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5package org.chromium.chrome.browser.favicon;
6
7import android.graphics.Bitmap;
8import android.graphics.Color;
9
10import org.chromium.base.CalledByNative;
11import org.chromium.chrome.browser.profiles.Profile;
12
13/**
14 * This is a helper class to use favicon_service.cc's functionality.
15 *
16 * You can request a favicon image by web page URL. Note that an instance of this class should be
17 * created & used & destroyed (by destroy()) in the same thread due to the C++ CancelableTaskTracker
18 * class requirement.
19 */
20public class FaviconHelper {
21
22    // Please keep in sync with favicon_types.h's IconType.
23    public static final int INVALID_ICON = 0;
24    public static final int FAVICON = 1 << 0;
25    public static final int TOUCH_ICON = 1 << 1;
26    public static final int TOUCH_PRECOMPOSED_ICON = 1 << 2;
27
28    private long mNativeFaviconHelper;
29
30    /**
31     * Callback interface for getting the result from getLocalFaviconImageForURL method.
32     */
33    public interface FaviconImageCallback {
34        /**
35         * This method will be called when the result favicon is ready.
36         * @param image   Favicon image.
37         * @param iconUrl Favicon image's icon url.
38         */
39        @CalledByNative("FaviconImageCallback")
40        public void onFaviconAvailable(Bitmap image, String iconUrl);
41    }
42
43    /**
44     * Allocate and initialize the C++ side of this class.
45     */
46    public FaviconHelper() {
47        mNativeFaviconHelper = nativeInit();
48    }
49
50    @Override
51    protected void finalize() {
52        // Ensure that destroy() was called.
53        assert mNativeFaviconHelper == 0;
54    }
55
56    /**
57     * Clean up the C++ side of this class. After the call, this class instance shouldn't be used.
58     */
59    public void destroy() {
60        assert mNativeFaviconHelper != 0;
61        nativeDestroy(mNativeFaviconHelper);
62        mNativeFaviconHelper = 0;
63    }
64
65    /**
66     * Get Favicon bitmap for the requested arguments. Retrieves favicons only for pages the user
67     * has visited on the current device.
68     * @param profile               Profile used for the FaviconService construction.
69     * @param pageUrl               The target Page URL to get the favicon.
70     * @param iconTypes             One of the IconType class values.
71     * @param desiredSizeInDip      The size of the favicon in dip we want to get.
72     * @param faviconImageCallback  A method to be called back when the result is available.
73     *                              Note that this callback is not called if this method returns
74     *                              false.
75     * @return                      True if GetLocalFaviconImageForURL is successfully called.
76     */
77    public boolean getLocalFaviconImageForURL(
78            Profile profile, String pageUrl, int iconTypes,
79            int desiredSizeInDip, FaviconImageCallback faviconImageCallback) {
80        assert mNativeFaviconHelper != 0;
81        return nativeGetLocalFaviconImageForURL(mNativeFaviconHelper, profile, pageUrl, iconTypes,
82                desiredSizeInDip, faviconImageCallback);
83    }
84
85    /**
86     * Return the dominant color of a given bitmap in {@link Color} format.
87     * @param image The bitmap image to find the dominant color for.
88     * @return The dominant color in {@link Color} format.
89     */
90    public int getDominantColorForBitmap(Bitmap image) {
91        return nativeGetDominantColorForBitmap(mNativeFaviconHelper, image);
92    }
93
94    /**
95     * Get 16x16 Favicon bitmap for the requested arguments. Only retrives favicons in synced
96     * session storage. (e.g. favicons synced from other devices).
97     * TODO(apiccion): provide a way to obtain higher resolution favicons.
98     * @param profile   Profile used for the FaviconService construction.
99     * @param pageUrl   The target Page URL to get the favicon.
100     *
101     * @return          16x16 favicon Bitmap corresponding to the pageUrl.
102     */
103    public Bitmap getSyncedFaviconImageForURL(Profile profile, String pageUrl) {
104        assert mNativeFaviconHelper != 0;
105        return nativeGetSyncedFaviconImageForURL(mNativeFaviconHelper, profile, pageUrl);
106    }
107
108    private static native long nativeInit();
109    private static native void nativeDestroy(long nativeFaviconHelper);
110    private static native boolean nativeGetLocalFaviconImageForURL(long nativeFaviconHelper,
111            Profile profile, String pageUrl, int iconTypes, int desiredSizeInDip,
112            FaviconImageCallback faviconImageCallback);
113    private static native Bitmap nativeGetSyncedFaviconImageForURL(long nativeFaviconHelper,
114            Profile profile, String pageUrl);
115    private static native int nativeGetDominantColorForBitmap(long nativeFaviconHelper,
116            Bitmap image);
117}
118