我正在使用此代码从Gmail获取标签信息，如here和here所述：
Pattern gmailPattern = Patterns.EMAIL_ADDRESS;
Account[] accounts = AccountManager.get(this).getAccounts();
for (Account account : accounts) {
if (gmailPattern.matcher(account.name).matches()) {
Cursor labelsCursor = getContentResolver().query(GmailContract.Labels.getLabelsUri( account), null, null, null, null);
}
}
问题是GmailContract无法解决。我已尝试过所有内容，但支持库和Google Play服务似乎都没有包含此类。那我在哪里可以找到它？
答案 0 :(得分：2)
您不需要任何图书馆。 GmailContract是由Google提供的帮助程序类。例如，您可以从this sample app复制它。无论如何它是：
/*
* Copyright 2012 Google Inc. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
import android.content.Context;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;
import android.content.pm.PermissionInfo;
import android.content.pm.ProviderInfo;
import android.net.Uri;
import android.text.TextUtils;
/**
* <p>Contract for use with the Gmail content provider.</p>
*
* <p>Developers can use this content provider to display label information to the user.
* <br/>
* The label information includes:
* <ul>
* <li>Label name</li>
* <li>Total number of conversations</li>
* <li>Number of unread conversations</li>
* <li>Label text color</li>
* <li>Label background color</li>
* </ul></p>
*
* <p>This content provider is available in Gmail version 2.3.6 or newer for Froyo/Gingerbread
* and version 4.0.5 and newer for Honeycomb and Ice Cream Sandwich</p>
* <p>An application can query the
* <a href="http://developer.android.com/reference/android/content/ContentResolver.html">
* Content Resolver</a> directly
* (or use a <a href="http://developer.android.com/guide/topics/fundamentals/loaders.html"
* target="_blank">Loader</a>)
* to obtain a Cursor with information for all labels on an account</p>
* <code>Cursor labelsCursor = getContentResolver().query(GmailContract.Labels.getLabelsUri(
* selectedAccount), null, null, null, null);</code>
*/
public final class GmailContract {
private GmailContract() {}
/**
* Permission required to access this {@link android.content.ContentProvider}
*/
public static final String PERMISSION =
"com.google.android.gm.permission.READ_CONTENT_PROVIDER";
/**
* Authority for the Gmail content provider.
*/
public static final String AUTHORITY = "com.google.android.gm";
static final String LABELS_PARAM = "/labels";
static final String LABEL_PARAM = "/label/";
static final String BASE_URI_STRING = "content://" + AUTHORITY;
static final String PACKAGE = "com.google.android.gm";
/**
* Check if the installed Gmail app supports querying for label information.
*
* @param c an application Context
* @return true if it's safe to make label API queries
*/
public static boolean canReadLabels(Context c) {
boolean supported = false;
try {
final PackageInfo info = c.getPackageManager().getPackageInfo(PACKAGE,
PackageManager.GET_PROVIDERS | PackageManager.GET_PERMISSIONS);
boolean allowRead = false;
if (info.permissions != null) {
for (int i = 0, len = info.permissions.length; i < len; i++) {
final PermissionInfo perm = info.permissions[i];
if (PERMISSION.equals(perm.name)
&& perm.protectionLevel < PermissionInfo.PROTECTION_SIGNATURE) {
allowRead = true;
break;
}
}
}
if (allowRead && info.providers != null) {
for (int i = 0, len = info.providers.length; i < len; i++) {
final ProviderInfo provider = info.providers[i];
if (AUTHORITY.equals(provider.authority) &&
TextUtils.equals(PERMISSION, provider.readPermission)) {
supported = true;
}
}
}
} catch (NameNotFoundException e) {
// Gmail app not found
}
return supported;
}
/**
* Table containing label information.
*/
public static final class Labels {
/**
* Label canonical names for default Gmail system labels.
*/
public static final class LabelCanonicalNames {
/**
* <p>Canonical name for the Primary inbox category</p>
* <p><i>Note: This label may not exist, based on the user's inbox configuration</i></p>
*/
public static final String CANONICAL_NAME_INBOX_CATEGORY_PRIMARY = "^sq_ig_i_personal";
/**
* Canonical name for the Social inbox category
* <p><i>Note: This label may not exist, based on the user's inbox configuration</i></p>
*/
public static final String CANONICAL_NAME_INBOX_CATEGORY_SOCIAL = "^sq_ig_i_social";
/**
* Canonical name for the Promotions inbox category
* <p><i>Note: This label may not exist, based on the user's inbox configuration</i></p>
*/
public static final String CANONICAL_NAME_INBOX_CATEGORY_PROMOTIONS = "^sq_ig_i_promo";
/**
* Canonical name for the Updates inbox category
* <p><i>Note: This label may not exist, based on the user's inbox configuration</i></p>
*/
public static final String CANONICAL_NAME_INBOX_CATEGORY_UPDATES =
"^sq_ig_i_notification";
/**
* Canonical name for the Forums inbox category
* <p><i>Note: This label may not exist, based on the user's inbox configuration</i></p>
*/
public static final String CANONICAL_NAME_INBOX_CATEGORY_FORUMS = "^sq_ig_i_group";
/**
* Canonical name for the Inbox label
* <p><i>Note: This label may not exist, based on the user's inbox configuration</i></p>
*/
public static final String CANONICAL_NAME_INBOX = "^i";
/**
* Canonical name for the Priority Inbox label
* <p><i>Note: This label may not exist, based on the user's inbox configuration</i></p>
*/
public static final String CANONICAL_NAME_PRIORITY_INBOX = "^iim";
/**
* Canonical name for the Starred label
*/
public static final String CANONICAL_NAME_STARRED = "^t";
/**
* Canonical name for the Sent label
*/
public static final String CANONICAL_NAME_SENT = "^f";
/**
* Canonical name for the Drafts label
*/
public static final String CANONICAL_NAME_DRAFTS = "^r";
/**
* Canonical name for the All Mail label
*/
public static final String CANONICAL_NAME_ALL_MAIL = "^all";
/**
* Canonical name for the Spam label
*/
public static final String CANONICAL_NAME_SPAM = "^s";
/**
* Canonical name for the Trash label
*/
public static final String CANONICAL_NAME_TRASH = "^k";
private LabelCanonicalNames() {}
}
/**
* The MIME-type of uri providing a directory of
* label items.
*/
public static final String CONTENT_TYPE =
"vnd.android.cursor.dir/vnd.com.google.android.gm.label";
/**
* The MIME-type of a label item.
*/
public static final String CONTENT_ITEM_TYPE =
"vnd.android.cursor.item/vnd.com.google.android.gm.label";
/**
* This string value is the canonical name of a label. Canonical names are not localized and
* are not user-facing.
*
* <p>Type: TEXT</p>
*/
public static final String CANONICAL_NAME = "canonicalName";
/**
* This string value is the user-visible name of a label. Names of system labels
* (Inbox, Sent, Drafts...) are localized.
*
* <p>Type: TEXT</p>
*/
public static final String NAME = "name";
/**
* This integer value is the number of conversations in this label.
*
* <p>Type: INTEGER</p>
*/
public static final String NUM_CONVERSATIONS = "numConversations";
/**
* This integer value is the number of unread conversations in this label.
*
* <p>Type: INTEGER</p>
*/
public static final String NUM_UNREAD_CONVERSATIONS = "numUnreadConversations";
/**
* This integer value is the label's foreground text color in 32-bit 0xAARRGGBB format.
*
* <p>Type: INTEGER</p>
*/
public static final String TEXT_COLOR = "text_color";
/**
* This integer value is the label's background color in 32-bit 0xAARRGGBB format.
*
* <p>Type: INTEGER</p>
*/
public static final String BACKGROUND_COLOR = "background_color";
/**
* This string column value is the uri that can be used in subsequent calls to
* {@link android.content.ContentProvider#query()} to query for information on the single
* label represented by this row.
*
* <p>Type: TEXT</p>
*/
public static final String URI = "labelUri";
/**
* Returns a URI that, when queried, will return the list of labels for an
* account.
* <p>
* To use the Labels API, an app must first find the email address of a
* valid Gmail account to query for label information. The <a href=
* "http://developer.android.com/reference/android/accounts/AccountManager.html"
* target="_blank">AccountManager</a> can return this information (<a
* href="https://developers.google.com/gmail/android">example</a>).
* </p>
*
* @param account Name of a valid Google account.
* @return The URL that can be queried to retrieve the the label list.
*/
public static Uri getLabelsUri(String account) {
return Uri.parse(BASE_URI_STRING + "/" + account + LABELS_PARAM);
}
private Labels() {}
}
}