Add a section to Site Settings listing USB devices.

chrome/android/java/src/org/chromium/chrome/browser/preferences/website/UsbChooserPreferences.java

+// Copyright 2016 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.chrome.browser.preferences.website;
+
+import android.os.Bundle;
+import android.preference.Preference;
+import android.preference.PreferenceFragment;
+import android.support.v4.view.MenuItemCompat;
+import android.support.v7.widget.SearchView;
+import android.util.Pair;
+import android.view.Menu;
+import android.view.MenuInflater;
+import android.view.MenuItem;
+import android.view.inputmethod.EditorInfo;
+import android.widget.ListView;
+import android.widget.TextView;
+
+import org.chromium.chrome.R;
+import org.chromium.chrome.browser.help.HelpAndFeedback;
+import org.chromium.chrome.browser.profiles.Profile;
+
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.HashMap;
+import java.util.Map;
+
+/**
+ * Shows a list of USB devices that the user has granted websites permission to access.
+ *
+ * When the user selects an item UsbDevicePreferences is launched to show which sites have access
+ * to the device.
+ */
+public class UsbChooserPreferences extends PreferenceFragment {
+    // The site settings category we are showing.
+    private SiteSettingsCategory mCategory;
+    // Multiple sites may have access to the same device. A canonical UsbInfo for each device is
+    // therefore arbitrarily chosen to represent it.
+    private Map<String, Pair<ArrayList<UsbInfo>, ArrayList<Website>>> mPermissionsByObject =
+            new HashMap<>();
+    // The view to show when the list is empty.
+    private TextView mEmptyView;
+    // The view for searching the list of items.
+    private SearchView mSearchView;
+    // If not blank, represents a substring to use to search for site names.
+    private String mSearch = "";
+
+    @Override
+    public void onActivityCreated(Bundle savedInstanceState) {
+        addPreferencesFromResource(R.xml.usb_chooser_preferences);
+        ListView listView = (ListView) getView().findViewById(android.R.id.list);
+        mEmptyView = (TextView) getView().findViewById(android.R.id.empty);
+        listView.setEmptyView(mEmptyView);
+        listView.setDivider(null);
+
+        String category = getArguments().getString(SingleCategoryPreferences.EXTRA_CATEGORY);
+        mCategory = SiteSettingsCategory.fromString(category);
+        String title = getArguments().getString(SingleCategoryPreferences.EXTRA_TITLE);
+        getActivity().setTitle(title);
+
+        setHasOptionsMenu(true);
+
+        super.onActivityCreated(savedInstanceState);
+    }
+
+    @Override
+    public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
+        menu.clear();
+        inflater.inflate(R.menu.website_preferences_menu, menu);
+
+        MenuItem searchItem = menu.findItem(R.id.search);
+        mSearchView = (SearchView) MenuItemCompat.getActionView(searchItem);
+        mSearchView.setImeOptions(EditorInfo.IME_FLAG_NO_FULLSCREEN);
+        SearchView.OnQueryTextListener queryTextListener = new SearchView.OnQueryTextListener() {
+            @Override
+            public boolean onQueryTextSubmit(String query) {
+                return true;
+            }
+
+            @Override
+            public boolean onQueryTextChange(String query) {
+                // Make search case-insensitive.
+                query = query.toLowerCase();
+
+                if (query.equals(mSearch)) return true;
+
+                mSearch = query;
+                getInfo();
+                return true;
+            }
+        };
+        mSearchView.setOnQueryTextListener(queryTextListener);
+
+        MenuItem help =
+                menu.add(Menu.NONE, R.id.menu_id_targeted_help, Menu.NONE, R.string.menu_help);
+        help.setIcon(R.drawable.ic_help_and_feedback);
+    }
+
+    @Override
+    public boolean onOptionsItemSelected(MenuItem item) {
+        if (item.getItemId() == R.id.menu_id_targeted_help) {
+            HelpAndFeedback.getInstance(getActivity())
+                    .show(getActivity(), getString(R.string.help_context_settings),
+                            Profile.getLastUsedProfile(), null);
+            return true;
+        }
+        return false;
+    }
+
+    @Override
+    public void onResume() {
+        super.onResume();
+
+        getInfo();
+    }
+
+    private class ResultsPopulator implements WebsitePermissionsFetcher.WebsitePermissionsCallback {
+        @Override
+        public void onWebsitePermissionsAvailable(Collection<Website> sites) {
+            // This method may be called after the activity has been destroyed.
+            // In that case, bail out.
+            if (getActivity() == null) return;
+
+            mPermissionsByObject.clear();
+            for (Website site : sites) {
+                for (UsbInfo info : site.getUsbInfo()) {
+                    if (mSearch.isEmpty() || info.getName().toLowerCase().contains(mSearch)) {
+                        Pair<ArrayList<UsbInfo>, ArrayList<Website>> entry =
+                                mPermissionsByObject.get(info.getObject());
+                        if (entry == null) {
+                            entry = Pair.create(new ArrayList<UsbInfo>(), new ArrayList<Website>());
+                            mPermissionsByObject.put(info.getObject(), entry);
+                        }
+                        entry.first.add(info);
+                        entry.second.add(site);
+                    }
+                }
+            }
+
+            resetList();
+        }
+    }
+
+    /**
+     * Refreshes |mPermissionsByObject| with new data from native.
+     *
+     * resetList() is called to refresh the view when the data is ready.
+     */
+    private void getInfo() {
+        WebsitePermissionsFetcher fetcher = new WebsitePermissionsFetcher(new ResultsPopulator());
+        fetcher.fetchPreferencesForCategory(mCategory);
+    }
+
+    private void resetList() {
+        getPreferenceScreen().removeAll();
+        addPreferencesFromResource(R.xml.usb_chooser_preferences);
+
+        if (mPermissionsByObject.isEmpty() && mSearch.isEmpty() && mEmptyView != null) {
+            mEmptyView.setText(R.string.website_settings_usb_no_devices);
+        }
+
+        for (Pair<ArrayList<UsbInfo>, ArrayList<Website>> entry : mPermissionsByObject.values()) {
+            Preference preference = new Preference(getActivity());
+            Bundle extras = preference.getExtras();
+            extras.putInt(UsbDevicePreferences.EXTRA_CATEGORY, mCategory.toContentSettingsType());
+            extras.putString(
+                    SingleCategoryPreferences.EXTRA_TITLE, getActivity().getTitle().toString());
+            extras.putSerializable(UsbDevicePreferences.EXTRA_USB_INFOS, entry.first);
+            extras.putSerializable(UsbDevicePreferences.EXTRA_SITES, entry.second);
+            preference.setIcon(R.drawable.settings_usb);
+            preference.setTitle(entry.first.get(0).getName());
+            preference.setFragment(UsbDevicePreferences.class.getCanonicalName());
+            getPreferenceScreen().addPreference(preference);
+        }
+    }
+}