我是一名新手安卓开发者,对于这个问题感到非常困惑。我正在制作一个简单的应用程序,其中有3个 TextViews:text、text2 和 text3。
- text 显示用户的纬度 - text2 显示用户的经度 - text3 显示用户与名为 "Azadi Square" 的地方之间的距离
该应用程序在三星 Galaxy S4 和三星 Galaxy Tab S 上正常运行,但在华为 Y511 和某些索尼 Xperia(我不知道确切的名称)上无法打开,并显示“应用程序已停止工作”的消息。
下面是我的 Java 代码:
- text 显示用户的纬度 - text2 显示用户的经度 - text3 显示用户与名为 "Azadi Square" 的地方之间的距离
该应用程序在三星 Galaxy S4 和三星 Galaxy Tab S 上正常运行,但在华为 Y511 和某些索尼 Xperia(我不知道确切的名称)上无法打开,并显示“应用程序已停止工作”的消息。
下面是我的 Java 代码:
public class Map extends Activity implements LocationListener {
private TextView text,text2,text3;
private String provider;
private LocationManager locationManager;
private double latitude,longitude;
private Location azadiSquare;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_map);
text = (TextView)findViewById(R.id.text);
text2 = (TextView)findViewById(R.id.text2);
text3 = (TextView)findViewById(R.id.text3);
locationManager = (LocationManager)getSystemService(Context.LOCATION_SERVICE);
Criteria criteria = new Criteria();
provider = locationManager.getBestProvider(criteria,false);
azadiSquare = new Location(provider);
azadiSquare.setLatitude(35.6996540);
azadiSquare.setLongitude(51.3379906);
Location location = locationManager.getLastKnownLocation(provider);
text.setText(location.getLatitude()+"");
text2.setText(location.getLongitude()+"");
text3.setText(distanceBetweenMeter(azadiSquare,location)+"");
}
@Override
protected void onResume() {
super.onResume();
locationManager.requestLocationUpdates(provider,400,1,this);
}
@Override
protected void onPause() {
super.onPause();
locationManager.removeUpdates(this);
}
@Override
public void onLocationChanged(Location location) {
latitude = location.getLatitude();
longitude = location.getLongitude();
text.setText(latitude+"");
text2.setText(longitude+"");
text3.setText(distanceBetweenMeter(azadiSquare,location)+"");
}
@Override
public void onStatusChanged(String s, int i, Bundle bundle) {
// TODO Auto-generated method stub
}
@Override
public void onProviderEnabled(String s) {
Toast.makeText(this,"Enabled new provider " + provider,Toast.LENGTH_LONG).show();
}
@Override
public void onProviderDisabled(String s) {
Toast.makeText(this,"Disabled provider " + provider,Toast.LENGTH_LONG).show();
}
private double getDistanceFromLatLonInKm(double lat1,double lon1,double lat2,double lon2) {
double R = 6371; // Radius of the earth in km
double dLat = deg2rad(lat2-lat1); // deg2rad below
double dLon = deg2rad(lon2-lon1);
double a =
Math.sin(dLat/2) * Math.sin(dLat/2) +
Math.cos(deg2rad(lat1)) * Math.cos(deg2rad(lat2)) *
Math.sin(dLon/2) * Math.sin(dLon/2)
;
double c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));
double d = R * c; // Distance in km
return d;
}
private double deg2rad(double deg) {
return deg * (Math.PI/180);
}
private int distanceBetweenMeter(Location location1, Location location2){
double distanceKM = getDistanceFromLatLonInKm(location1.getLatitude(),location1.getLongitude(),
location2.getLatitude(),location2.getLongitude());
int distanceMeter = (int)(distanceKM*1000);
return distanceMeter;
}
}
注意:我刚刚删除了导入项!
清单文件:
<?xml version="1.0" encoding="utf-8"?>
<uses-permission android:name="android.permission.INTERNET"/>
<uses-permission android:name="android.permission.ACCESS_FINE_LOCATION"/>
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION"/>
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".Map" android:screenOrientation="landscape">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
注意:我在打开应用前已经打开了手机的定位功能,所以这不是问题。另外我想说的是所有计算都没有问题,它们都能正常工作。