我有一个Facebook应用程序（画布）托管在Heroku上，比如 xxxx.herokuapp.com/index.php。此外，我在画布之外还有一个网站，比如说 xxxx.herokuapp.com/welcome.php 我鼓励人们了解有关该应用程序的更多信息并安装它。
是否有任何小部件"安装应用程序"将欢迎.php访问者重定向到索引.php，要求登录（如有必要）和安装应用程序的权限？
我目前正在使用"登录按钮"，但它只是执行登录步骤。
谢谢
不，没有官方的Install App按钮，但您可以自己创建一个。
创建一个按钮，该按钮将在单击索引.php页面时将访问者重定向到索引页面，并在index.php页面上检查用户是否已登录，如果没有，则将他们重定向到具有应用所需的任何权限的身份验证流，然后返回index.php。
如果你想要一个片段，我可以发布它。
编辑：根据要求，这是代码片段：
index.php
<?php
# Path to facebook's PHP SDK, Assuming it's in the root.
# Download latest SDK from https://github.com/facebook/facebook-php-sdk
require_once("facebook.php");
# Facebook application config.
$config = array(
'appId' => 'YOUR_APP_ID',
'secret' => 'YOUR_APP_SECRET',
);
# Create a new facebook object.
$facebook = new Facebook($config);
# Current user ID.
$user_id = $facebook->getUser();
# Check to see if we have user ID.
if($user_id) {
# If we have a user ID, it probably means we have a logged in user.
# If not, we'll get an exception, which we handle below.
try {
# Get logged in user's profile info:
$user_info = $facebook->api('/me');
} catch(FacebookApiException $e) {
// If the user is logged out, you can have a
// user ID even though the access token is invalid.
// In this case, we'll get an exception, so we'll just redirect the user to login again here.
$login_url = $facebook->getLoginUrl();
echo ("<script>top.location = '$login_url';</script>");
error_log($e->getType());
error_log($e->getMessage());
}
} else {
# No user, redirect user to login and give the required permissions to perform tasks.
$login_url = $facebook->getLoginUrl();
echo ("<script>top.location = '$login_url';</script>");
}
?>
welcome.php示例：http://jsfiddle.net/9CCcB/
在这个例子中，我使用了Nicolas Gallagher的CSS3社交登录按钮，你可以对按钮使用任何样式。
<!doctype html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Welcome</title>
<style>
/*
CSS3 Social Sign-in Buttons by Nicolas Gallagher
Link: http://nicolasgallagher.com/lab/css3-social-signin-buttons/
*/
.btn-auth {
position: relative;
display: inline-block;
height: 22px;
padding: 0 1em;
border: 1px solid #999;
border-radius: 2px;
margin: 0;
text-align: center;
text-decoration: none;
font-size: 14px;
line-height: 22px;
white-space: nowrap;
cursor: pointer;
color: #222;
background: #fff;
-webkit-box-sizing: content-box;
-moz-box-sizing: content-box;
box-sizing: content-box;
/* iOS */
-webkit-appearance: none; /* 1 */
/* IE6/7 hacks */
*overflow: visible; /* 2 */
*display: inline; /* 3 */
*zoom: 1; /* 3 */
}
.btn-auth:hover,
.btn-auth:focus,
.btn-auth:active {
color: #222;
text-decoration: none;
}
.btn-auth:before {
content: "";
float: left;
width: 22px;
height: 22px;
background: url(https://raw.github.com/necolas/css3-social-signin-buttons/master/auth-icons.png) no-repeat 99px 99px;
}
/*
* 36px
*/
.btn-auth.large {
height: 36px;
line-height: 36px;
font-size: 20px;
}
.btn-auth.large:before {
width: 36px;
height: 36px;
}
/*
* Remove excess padding and border in FF3+
*/
.btn-auth::-moz-focus-inner {
border: 0;
padding: 0;
}
/* Facebook (extends .btn-auth)
========================================================================== */
.btn-facebook {
border-color: #29447e;
border-bottom-color: #1a356e;
color: #fff;
background-color: #5872a7;
background-image: -webkit-gradient(linear, 0 0, 0 100%, from(#637bad), to(#5872a7));
background-image: -webkit-linear-gradient(#637bad, #5872a7);
background-image: -moz-linear-gradient(#637bad, #5872a7);
background-image: -ms-linear-gradient(#637bad, #5872a7);
background-image: -o-linear-gradient(#637bad, #5872a7);
background-image: linear-gradient(#637bad, #5872a7);
-webkit-box-shadow: inset 0 1px 0 #879ac0;
box-shadow: inset 0 1px 0 #879ac0;
}
.btn-facebook:hover,
.btn-facebook:focus {
color: #fff;
background-color: #3b5998;
}
.btn-facebook:active {
color: #fff;
background: #4f6aa3;
-webkit-box-shadow: inset 0 1px 0 #45619d;
box-shadow: inset 0 1px 0 #45619d;
}
/*
* Icon
*/
.btn-facebook:before {
border-right: 1px solid #465f94;
margin: 0 1em 0 -1em;
background-position: 0 0;
}
.btn-facebook.large:before {
background-position: 0 -22px;
}
</style>
</head>
<body>
<center><a class="btn-auth btn-facebook large" href="http://domain.com/">Sign in with <b>Facebook</b></a></center>
</body>
</html>