我可以收听到达的短信，但搜索后我找不到收听到达 GMAIL 的电子邮件的方法。我将在任何级别的操作系统上采取任何可能的方式。谢谢。
【问题讨论】：
请参阅DashClock Widget 中的GmailContract 了解工作示例。
复制/粘贴下面的源代码以供参考，以防万一网址不可用。
/*
* 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.
*/
package com.google.android.apps.dashclock.gmail;
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 {
/**
* Canonical name for the Inbox label
*/
public static final String CANONICAL_NAME_INBOX = "^i";
/**
* Canonical name for the Priority Inbox label
*/
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() {}
}
}
希望这会有所帮助。
【讨论】：
据我所知，无法直接访问实际消息。我知道的最好方法是使用 Java MAIL for Android 库 (http://code.google.com/p/javamail-android/) 并使用 IMAP 协议来获取您要查找的消息。
但您的实际问题是关于从 gmail 获取事件。要获取它们，您可以使用 ContentObserver。首先，声明你自己的 ContentObserver 子类：
class GmailContentObserver extends ContentObserver {
public GmailContentObserver(Handler handler) {
super(handler);
}
@Override
public void onChange(boolean selfChange) {
onChange(selfChange, null);
}
@Override
public void onChange(boolean selfChange, Uri uri) {
// This is where you will get your change notifications
// for each received e-mails. This method will be called multiple times per
// received e-mail. At least 3, but it depends on the way you register
// your observer and on your gmail account set up (number of labels).
// You will also get calls for other events. Remember that this method is
// called for any change on the local gmail repository. Receiving an e-mail
// is only one of many actions that will change this repository.
Toast.makeText(MainActivity.this,"gmail event",Toast.LENGTH_LONG).show();
}
}
然后注册你的 ContentObserver：
GmailContentObserver gco = new GmailContentObserver(new Handler());
ContentResolver cr = getContentResolver();
cr.registerContentObserver(Uri.parse("content://gmail-ls"),true,gco);
就是这样！
请注意，当您不再需要观察者或您的应用程序/服务关闭时，您还应该取消注册观察者。
在实例化观察者时还要注意new Hanlder()。这将确定在哪个线程上调用 onChange 方法。创建 Handler 对象的线程是调用 onChange 的线程（在我的示例中，您看不到这一点，但它是 UI 线程，即在我的 Activity 中调用 onCreate 的线程）。
注册观察者时，有两个参数：要观察的 URI 和是否要观察后代。在上面的示例代码中，您将收到有关 URI content://gmail-ls 的通知，但也将收到例如 content://gmail-ls/foo@gmail.com 的通知，foo@gmail.com 是您的 gmail 帐户。还有更多的后代 URI（尤其是标签）。要获得更少的事件，您可以为 content://gmail-ls/foo@gmail.com 注册观察者并将第二个参数设置为 false。
鉴于这种机制，理论上如果您想观察给定 gmail 标签的变化，您可以查询标签 id（请参阅 gmail api）并注册相应的 URI content://gmail-ls/foo@gmail.com/label/80，80 是标签 id。但由于某种原因，这不起作用。
还要检查已经提到的 gmail api 的代码，以确定已安装的 gmail 应用程序是否具有内容提供程序（取决于 gmail 的版本）。
【讨论】：
如果您想获取电子邮件的内容，我建议使用 Gmail REST API 非常好（但您需要在您的应用程序中获得用户授权）。
var url = 'https://www.googleapis.com/gmail/v1/users/me/messages?q=in%3Ainbox&'
我们在我们的应用程序Speaking Email（无耻插件）中使用了它，这是一个使用 javascript 的科尔多瓦应用程序，gmail API 非常适合我们。
【讨论】：