我正在尝试编写一个在 Map 上显示当前设备位置的应用程序 . 当我尝试将其安装到设备上时,它说它无法找到我主要活动的课程 . 它还说dalvikvm无法解析类的超类,这显然是MapActivity . 有任何想法吗?谢谢 .
import java.util.List;
import com.google.android.maps.GeoPoint;
import com.google.android.maps.MapActivity;
import com.google.android.maps.MapController;
import com.google.android.maps.MapView;
import com.google.android.maps.Overlay;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Point;
import android.graphics.drawable.Drawable;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.os.Bundle;
import android.view.KeyEvent;
import android.view.ViewGroup;
import android.view.ViewGroup.LayoutParams;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ZoomControls;
public class WcFinderActivity extends MapActivity implements LocationListener {
/** Called when the activity is first created. */
EditText txted = null;
Button btnSimple = null;
MapView gMapView = null;
MapController mc = null;
Drawable defaultMarker = null;
GeoPoint p = null;
double latitude = 18.9599990845, longitude = 72.819999694;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
// Creating TextBox displying Lat, Long
txted = (EditText) findViewById(R.id.id1);
String currentLocation = "Lat: " + latitude + " Lng: " + longitude;
txted.setText(currentLocation);
// Creating and initializing Map
gMapView = (MapView) findViewById(R.id.myGMap);
p = new GeoPoint((int) (latitude * 1000000), (int) (longitude * 1000000));
gMapView.setSatellite(true);
mc = gMapView.getController();
mc.setCenter(p);
mc.setZoom(14);
// Add a location mark
MyLocationOverlay myLocationOverlay = new MyLocationOverlay();
List<Overlay> list = gMapView.getOverlays();
list.add(myLocationOverlay);
// Adding zoom controls to Map
ZoomControls zoomControls = (ZoomControls) gMapView.getZoomControls();
zoomControls.setLayoutParams(new ViewGroup.LayoutParams(LayoutParams.WRAP_CONTENT,
LayoutParams.WRAP_CONTENT));
gMapView.addView(zoomControls);
gMapView.displayZoomControls(true);
// Getting locationManager and reflecting changes over map if distance travel by
// user is greater than 500m from current location.
LocationManager lm = (LocationManager) getSystemService(Context.LOCATION_SERVICE);
lm.requestLocationUpdates(LocationManager.GPS_PROVIDER, 1000L, 500.0f, this);
}
/* This method is called when use position will get changed */
public void onLocationChanged(Location location) {
if (location != null) {
double lat = location.getLatitude();
double lng = location.getLongitude();
String currentLocation = "Lat: " + lat + " Lng: " + lng;
txted.setText(currentLocation);
p = new GeoPoint((int) lat * 1000000, (int) lng * 1000000);
mc.animateTo(p);
}
}
public void onProviderDisabled(String provider) {
// required for interface, not used
}
public void onProviderEnabled(String provider) {
// required for interface, not used
}
public void onStatusChanged(String provider, int status, Bundle extras) {
// required for interface, not used
}
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}
/* User can zoom in/out using keys provided on keypad */
public boolean onKeyDown(int keyCode, KeyEvent event) {
if (keyCode == KeyEvent.KEYCODE_I) {
gMapView.getController().setZoom(gMapView.getZoomLevel() + 1);
return true;
} else if (keyCode == KeyEvent.KEYCODE_O) {
gMapView.getController().setZoom(gMapView.getZoomLevel() - 1);
return true;
} else if (keyCode == KeyEvent.KEYCODE_S) {
gMapView.setSatellite(true);
return true;
} else if (keyCode == KeyEvent.KEYCODE_T) {
gMapView.setTraffic(true);
return true;
}
return false;
}
/* Class overload draw method which actually plot a marker,text etc. on Map */
protected class MyLocationOverlay extends com.google.android.maps.Overlay {
@Override
public boolean draw(Canvas canvas, MapView mapView, boolean shadow, long when) {
Paint paint = new Paint();
super.draw(canvas, mapView, shadow);
// Converts lat/lng-Point to OUR coordinates on the screen.
Point myScreenCoords = new Point();
mapView.getProjection().toPixels(p, myScreenCoords);
paint.setStrokeWidth(1);
paint.setARGB(255, 255, 255, 255);
paint.setStyle(Paint.Style.STROKE);
Bitmap bmp = BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher);
canvas.drawBitmap(bmp, myScreenCoords.x, myScreenCoords.y, paint);
canvas.drawText("I am here...", myScreenCoords.x, myScreenCoords.y, paint);
return true;
}
}
}
01-18 15:04:07.223:W / dalvikvm(3554):无法解析Lcom / tecmark / WcFinderActivity的超类; (23)01-18 15:04:07.238:W / dalvikvm(3554):类'Lcom / tecmark / WcFinderActivity'的链接;失败01-18 15:04:07.238:D / AndroidRuntime(3554):关闭VM 01-18 15:04:07.238:W / dalvikvm(3554):threadid = 3:线程退出未捕获异常(组= 0x4001b180) 01-18 15:04:07.238:E / AndroidRuntime(3554):未捕获的处理程序:由于未捕获的异常导致线程主要退出01-18 15:04:07.278:E / AndroidRuntime(3554):java.lang.RuntimeException:无法实例化活动ComponentInfo {com.tecmark / com.tecmark.WcFinderActivity}:java.lang.ClassNotFoundException:com.tecmark.WcFinderActivity in loader dalvik.system.PathClassLoader@43e57a18 01-18 15:04:07.278:E / AndroidRuntime(3554) :at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2417)01-18 15:04:07.278:E / AndroidRuntime(3554):at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2512)01-18 15:04:07.278:E / AndroidRuntime(3554):在android.app.ActivityThread.access $ 2200(ActivityThread.java:119)01-18 15:04:07.278:E / AndroidRuntime(3554):在android.app . ActivityThread $ H.handleMessage( ActivityThread.java:1863)01-18 15:04:07.278:E / AndroidRuntime(3554):在android.os.Handler.dispatchMessage(Handler.java:99)01-18 15:04:07.278:E / AndroidRuntime( 3554):在android.os.Looper.loop(Looper.java:123)01-18 15:04:07.278:E / AndroidRuntime(3554):在android.app.ActivityThread.main(ActivityThread.java:4363)01 -18 15:04:07.278:E / AndroidRuntime(3554):at java.lang.reflect.Method.invokeNative(Native Method)01-18 15:04:07.278:E / AndroidRuntime(3554):at java.lang . reflect.Method.invoke(Method.java:521)01-18 15:04:07.278:E / AndroidRuntime(3554):at com.android.internal.os.ZygoteInit $ MethodAndArgsCaller.run(ZygoteInit.java:860)01 -18 15:04:07.278:E / AndroidRuntime(3554):at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)01-18 15:04:07.278:E / AndroidRuntime(3554): at dalvik.system.NativeStart.main(Native Method)01-18 15:04:07.278:E / AndroidRuntime(3554):引起:java.lang.ClassNotFoundException:com.tecmark.WcFinderActivity in loader dalvik.system.PathClassLoader @ 4 3e57a18 01-18 15:04:07.278:E / AndroidRuntime(3554):at dalvik.system.PathClassLoader.findClass(PathClassLoader.java:243)01-18 15:04:07.278:E / AndroidRuntime(3554):at java .lang.ClassLoader.loadClass(ClassLoader.java:573)01-18 15:04:07.278:E / AndroidRuntime(3554):at java.lang.ClassLoader.loadClass(ClassLoader.java:532)01-18 15:04 :07.278:E / AndroidRuntime(3554):在android.app.Instrumentation.newActivity(Instrumentation.java:1021)01-18 15:04:07.278:E / AndroidRuntime(3554):在android.app.ActivityThread.performLaunchActivity( ActivityThread.java:2409)01-18 15:04:07.278:E / AndroidRuntime(3554):... 11更多
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<?xml version="1.0" ?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.tecmark"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk android:minSdkVersion="7" />
<uses-permission android:name="android.permission.INTERNET"></uses-permission>
<uses-library android:name="com.google.android.maps" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"></uses-permission>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"></uses-permission>
<application
android:icon="@drawable/ic_launcher"
android:label="@string/app_name" >
<activity
android:name=".WcFinderActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
</manifest>
1 回答
对不起我犯了一个愚蠢的错误 . 我在应用程序标签中移动了uses-library标签,它现在编译并安装在手机上 . 我认为这解释了超类也不能被重新发送错误 . 我的活动扩展了MapActivity,这可能是在谷歌api库中定义的,未在应用程序标签之间声明 .