我正在创建一个Android应用程序(使用Java),它将从文件中读取 SWEREF99 TM 坐标,并将它们转换为 WGS84 (long-lat)坐标,并在对面方向。为此,我将使用 JMapProjLib , Proj4j 或 Proj4js (我将使用Java访问的JavaScript库{ {1}})。
问题在于我无法弄清楚如何使用这些库,因为文档很少...... 我已经尝试了 JMapProjLib -JavaLibrary,但它没有给我正确的结果,我也尝试过使用 Proj4js 2.3.3 ,但我甚至不能让后面提到的工作......
我正在使用的JavaScript(以及一些HTML)代码,使用 Proj4js 2.3.3 (目前我只在HTML文件中尝试此脚本,因此浏览器应显示转换完成后弹出消息说“完成!”:
ScriptEngine
我正在尝试的Java代码(使用 JMapProjLib ):
<!DOCTYPE html>
<html>
<head>
<title>Proj4js Testing</title>
</head>
<body onload="convertCoordinates()">
<script type"text/javascript" src="proj4js.js"></script>
<script type="text/javascript">
// Convert coordinates
function convertCoordinates()
// Define the target projection (SWEREF99 TM)
var targetProjection = "+proj=utm +zone=33 +ellps=GRS80 +towgs84=0,0,0,0,0,0,0 +units=m +no_defs";
// Convert the WGS84 coordinates Lon: 15 and Lat: 55 to SWEREF99 TM coordinates
proj4(targetProjection, [15, 55]);
// Just show an alert message telling that the code has executed properly
alert("Done!");
}
</script>
</body>
</html>
引用到我的Java项目的 JMapProjLib -library包含编译为{{1的git-repository中的文件夹/**
* Convert a long-lat coordinate to a SWEREF99 TM coordinate.
*
* @param longLatCoordinate The long-lat coordinate to convert.
*
* @return The converted SWEREF99 TM coordinate.
*/
public static SWEREF99TMCoordinate longLatToSWEREF99TM(LongLatCoordinate longLatCoordinate) {
// Create a new SWEREF99 TM projection
Projection projection = ProjectionFactory.fromPROJ4Specification(new String[] {
"+proj=tmerc",
"+zone=33",
"+ellps=GRS80",
"+towgs84=0,0,0,0,0,0,0",
"+units=m",
"+no_defs"
});
// Convert the LongLatCoordinate to a Point2D.Double
Point2D.Double longLatPoint = new Point2D.Double(longLatCoordinate.getLongitude(), longLatCoordinate.getLatitude());
// Get the location as a SWEREF99 TM Point2D.Double
Point2D.Double sweref99TMPoint = projection.transform(longLatPoint, new Point2D.Double());
// COnvert the location to a SWEREF99TMCoordinate
SWEREF99TMCoordinate sweref99TMCoordinate = new SWEREF99TMCoordinate(sweref99TMPoint.x, sweref99TMPoint.y);
// Return the projected coordinate
return sweref99TMCoordinate;
}
和src/com/jhlabs/map
中的内容我使用 Eclipse 文件。
由于 JavaScript -library Proj4js 对我来说看起来更“完美”,我宁愿将它与Java结合使用{{1}所以我现在真正需要的只是某种文档,或者可以向我解释这一点的人。
答案 0 :(得分:1)