Question

我有一个家庭作业，我应该显示与之交互的人的用户名并保存Google Map标记的位置。我很难弄清楚如何解决这个问题 - 我已经得到了标记标题/工具提示以显示所有标记的当前用户名，但无法弄清楚如何将标记工具提示设置为显示已移动的用户的用户名。

这是代码（我正在编辑教授提供的代码）：

<?php
require_once "../../config.php";
require_once $CFG->dirroot."/pdo.php";
require_once $CFG->dirroot."/lib/lms_lib.php";

session_start();

// Sanity checks
$LTI = requireData(array('user_id', 'link_id', 'role','context_id'));
$instructor = isset($LTI['role']) && $LTI['role'] == 1 ;

$p = $CFG->dbprefix;
if ( isset($_POST['lat']) && isset($_POST['lng']) ) {
    if ( abs($_POST['lat']) > 85 || abs($_POST['lng']) > 180 ) {
        $_SESSION['error'] = "Latitude or longitude out of range";
        header( 'Location: '.sessionize('index.php') ) ;
        return;
    }
    $sql = "INSERT INTO {$p}sample_map 
        (context_id, user_id, lat, lng, displayname, updated_at) 
        VALUES ( :CID, :UID, :LAT, :LNG, :DN, NOW() ) 
        ON DUPLICATE KEY 
        UPDATE lat = :LAT, lng = :LNG, displayname = :DN, updated_at = NOW()";
    $stmt = $pdo->prepare($sql);
    $stmt->execute(array(
        ':CID' => $LTI['context_id'],
        ':UID' => $LTI['user_id'],
        ':LAT' => $_POST['lat'],
        ':LNG' => $_POST['lng'],
    ':DN' => $LTI['displayname']));
    $_SESSION['success'] = 'Location updated...';
    header( 'Location: '.sessionize('index.php') ) ;
    return;
}

// Retrieve our row
$stmt = $pdo->prepare("SELECT lat,lng FROM {$p}sample_map 
        WHERE context_id = :CID AND user_id = :UID");
$stmt->execute(array(":CID" => $LTI['context_id'], ":UID" => $LTI['user_id']));
$row = $stmt->fetch(PDO::FETCH_ASSOC);
// The default for latitude and longitude
$lat = 42.279070216140425;
$lng = -83.73981015789798;
if ( $row !== false ) {
    if ( abs($row['lat']) <= 90 ) $lat = $row['lat'];
    if ( abs($row['lng']) <= 180 ) $lng = $row['lng'];
}

//Retrieve the other rows. Retrieve all the points other than you
//Add them to the points array. Made each row an array. Dump em out.
$stmt = $pdo->prepare("SELECT lat,lng,displayname FROM {$p}sample_map 
        JOIN {$p}lti_user
        ON {$p}sample_map.user_id = {$p}lti_user.user_id
        WHERE context_id = :CID AND {$p}sample_map.user_id <> :UID");
$stmt->execute(array(":CID" => $LTI['context_id'], ":UID" => $LTI['user_id']));
$points = array();
while ( $row = $stmt->fetch(PDO::FETCH_ASSOC) ) {
    if ( abs($row['lat']) > 90 ) $row['lat'] = 89;
    if ( abs($row['lng']) > 180 ) $row['lng'] = 179;
    $points[] = array($row['lat']+0.0,$row['lng']+0.0);  
}

?>
<html><head><title>Map for 
<?php echo($LTI['context_title']); ?>
</title>
<script src="//maps.googleapis.com/maps/api/js?v=3.exp&sensor=false"></script>
<script type="text/javascript">
var map;

// https://developers.google.com/maps/documentation/javascript/reference
function initialize_map() {
  var myLatlng = new google.maps.LatLng(<?php echo($lat.", ".$lng); ?>);
  window.console && console.log("Building map...");

  var myOptions = {
     zoom: 2,
     center: myLatlng,
     mapTypeId: google.maps.MapTypeId.ROADMAP
  }

  map = new google.maps.Map(document.getElementById("map_canvas"), myOptions); 

  var marker = new google.maps.Marker({
    draggable: true,
    position: myLatlng, 
    map: map,
    title: "Your location"
  });

  google.maps.event.addListener(marker, 'dragend', function (event) {
    // getPosition returns a google.maps.LatLng class for
    // for the dropped marker
    window.console && console.log(this.getPosition());
    // TODO: Fix these next two lines - search the web for a solution
    document.getElementById("latbox").value = this.getPosition().lat();
    document.getElementById("lngbox").value = this.getPosition().lng();
  });

  // Add the other points
  window.console && console.log("Loading "+other_points.length+" points");
  for ( var i = 0; i < other_points.length; i++ ) {
    var row = other_points[i];
    // if ( i < 3 ) { alert(row); }
    var newLatlng = new google.maps.LatLng(row[0], row[1]);
    var iconpath = '<?php echo($CFG->staticroot); ?>/static/img/icons/';
    var icon = 'green.png';
  var displayname = '<?php echo($LTI['user_displayname']) ?>';
    var marker = new google.maps.Marker({
      position: newLatlng,
      map: map,
      icon: iconpath + icon,
      // TODO: See if you can get the user's displayname here
      title : displayname,
     });
  }
}

// Load the other points 
other_points = 
<?php echo( json_encode($points));?> 
;
</script>
</head>
<body style="font-family: sans-serif;" onload="initialize_map();">
<?php
if ( isset($_SESSION['error']) ) {
    echo '<p style="color:red">'.$_SESSION['error']."</p>\n";
    unset($_SESSION['error']);
}
if ( isset($_SESSION['success']) ) {
    echo '<p style="color:green">'.$_SESSION['success']."</p>\n";
    unset($_SESSION['success']);
}

?>
<div id="map_canvas" style="margin: 10px; width:500px; max-width: 100%; height:500px"></div>
<form method="post">
 Latitude: <input size="30" type="text" id="latbox" name="lat" 
  <?php echo(' value="'.htmlent_utf8($lat).'" '); ?> >
 Longitude: <input size="30" type="text" id="lngbox" name="lng"
  <?php echo(' value="'.htmlent_utf8($lng).'" '); ?> >
 <button type="submit">Save Location</button>
</form>
<?php
footerContent();

Answer 1

嘿，我不确定你是在SI 364还是SI664，但无论如何我现在正在做同样的任务。 Somesh（GSI）告诉我要做的是创建一个新的php数组，就像点数一样，并在该数组中插入display_names。然后在代码中找到变量other_points，并为名称设置类似的javascript变量。然后看看如何读取other_points，并类似地读取谷歌地图功能中名称的变量。我还没有想到它，但也许这可能对你有所帮助。

在Google地图标记工具提示中显示用户名？

1 个答案: