我是 android 新手,我正在测试一个在 android 中提供道路路径的应用程序。但是我在这里有很多错误(如下所示)。
public class MapRouteActivity extends MapActivity {
LinearLayout linearLayout;
MapView mapView;
private Road mRoad;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
mapView = (MapView) findViewById(R.id.mapview);
mapView.setBuiltInZoomControls(true);
new Thread() {
@Override
public void run() {
double fromLat = 49.85, fromLon = 24.016667, toLat = 50.45, toLon = 30.523333;
String url = RoadProvider
.getUrl(fromLat, fromLon, toLat, toLon);
InputStream is = getConnection(url);
mRoad = RoadProvider.getRoute(is);
mHandler.sendEmptyMessage(0);
}
}.start();
}
Handler mHandler = new Handler() {
public void handleMessage(android.os.Message msg) {
TextView textView = (TextView) findViewById(R.id.description);
textView.setText(mRoad.mName + " " + mRoad.mDescription);
MapOverlay mapOverlay = new MapOverlay(mRoad, mapView);
List<Overlay> listOfOverlays = mapView.getOverlays();
listOfOverlays.clear();
listOfOverlays.add(mapOverlay);
mapView.invalidate();
};
};
private InputStream getConnection(String url) {
InputStream is = null;
try {
URLConnection conn = new URL(url).openConnection();
is = conn.getInputStream();
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return is;
}
@Override
protected boolean isRouteDisplayed() {
return false;
}
}
class MapOverlay extends com.google.android.maps.Overlay {
Road mRoad;
ArrayList<GeoPoint> mPoints;
public MapOverlay(Road road, MapView mv) {
mRoad = road;
if (road.mRoute.length > 0) {
mPoints = new ArrayList<GeoPoint>();
for (int i = 0; i < road.mRoute.length; i++) {
mPoints.add(new GeoPoint((int) (road.mRoute[i][1] * 1000000),
(int) (road.mRoute[i][0] * 1000000)));
}
int moveToLat = (mPoints.get(0).getLatitudeE6() + (mPoints.get(
mPoints.size() - 1).getLatitudeE6() - mPoints.get(0)
.getLatitudeE6()) / 2);
int moveToLong = (mPoints.get(0).getLongitudeE6() + (mPoints.get(
mPoints.size() - 1).getLongitudeE6() - mPoints.get(0)
.getLongitudeE6()) / 2);
GeoPoint moveTo = new GeoPoint(moveToLat, moveToLong);
MapController mapController = mv.getController();
mapController.animateTo(moveTo);
mapController.setZoom(7);
}
}
@Override
public boolean draw(Canvas canvas, MapView mv, boolean shadow, long when) {
super.draw(canvas, mv, shadow);
drawPath(mv, canvas);
return true;
}
public void drawPath(MapView mv, Canvas canvas) {
int x1 = -1, y1 = -1, x2 = -1, y2 = -1;
Paint paint = new Paint();
paint.setColor(Color.GREEN);
paint.setStyle(Paint.Style.STROKE);
paint.setStrokeWidth(3);
for (int i = 0; i < mPoints.size(); i++) {
Point point = new Point();
mv.getProjection().toPixels(mPoints.get(i), point);
x2 = point.x;
y2 = point.y;
if (i > 0) {
canvas.drawLine(x1, y1, x2, y2, paint);
}
x1 = x2;
y1 = y2;
}
}
}
当我午餐这段代码时,我遇到了所有这些错误,如下所示:
07-30 14:03:08.969: W/dalvikvm(6934): Unable to resolve superclass of Lcom/test/MapRouteActivity; (17)
07-30 14:03:08.969: W/dalvikvm(6934): Link of class 'Lcom/test/MapRouteActivity;' failed
07-30 14:03:08.969: W/dalvikvm(6934): threadid=1: thread exiting with uncaught exception (group=0x2aac87c8)
07-30 14:03:08.979: E/AndroidRuntime(6934): FATAL EXCEPTION: main
07-30 14:03:08.979: E/AndroidRuntime(6934): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.test/com.test.MapRouteActivity}: java.lang.ClassNotFoundException: com.test.MapRouteActivity in loader dalvik.system.PathClassLoader[/data/app/com.test-1.apk]
07-30 14:03:08.979: E/AndroidRuntime(6934): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2585)
07-30 14:03:08.979: E/AndroidRuntime(6934): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2679)
07-30 14:03:08.979: E/AndroidRuntime(6934): at android.app.ActivityThread.access$2300(ActivityThread.java:125)
07-30 14:03:08.979: E/AndroidRuntime(6934): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:2033)
07-30 14:03:08.979: E/AndroidRuntime(6934): at android.os.Handler.dispatchMessage(Handler.java:99)
07-30 14:03:08.979: E/AndroidRuntime(6934): at android.os.Looper.loop(Looper.java:123)
07-30 14:03:08.979: E/AndroidRuntime(6934): at android.app.ActivityThread.main(ActivityThread.java:4627)
07-30 14:03:08.979: E/AndroidRuntime(6934): at java.lang.reflect.Method.invokeNative(Native Method)
07-30 14:03:08.979: E/AndroidRuntime(6934): at java.lang.reflect.Method.invoke(Method.java:521)
07-30 14:03:08.979: E/AndroidRuntime(6934): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:868)
07-30 14:03:08.979: E/AndroidRuntime(6934): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:626)
07-30 14:03:08.979: E/AndroidRuntime(6934): at dalvik.system.NativeStart.main(Native Method)
07-30 14:03:08.979: E/AndroidRuntime(6934): Caused by: java.lang.ClassNotFoundException: com.test.MapRouteActivity in loader dalvik.system.PathClassLoader[/data/app/com.test-1.apk]
07-30 14:03:08.979: E/AndroidRuntime(6934): at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:243)
07-30 14:03:08.979: E/AndroidRuntime(6934): at java.lang.ClassLoader.loadClass(ClassLoader.java:573)
07-30 14:03:08.979: E/AndroidRuntime(6934): at java.lang.ClassLoader.loadClass(ClassLoader.java:532)
07-30 14:03:08.979: E/AndroidRuntime(6934): at android.app.Instrumentation.newActivity(Instrumentation.java:1021)
07-30 14:03:08.979: E/AndroidRuntime(6934): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2577)
07-30 14:03:08.979: E/AndroidRuntime(6934): ... 11 more