我是android开发的新手，真的很困惑这个问题。 我制作了一个简单的应用程序，它有3个TextViews：text，text2和text3。
该应用在 Samsung Galaxy S4 和 Samsung Galaxy Tab S 上正常运行，但在 Huawei Y511 和 Sony Xperias （我不知道具体名称。），应用程序无法打开并说 The App has unfortunately stopped
这是我的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！
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：我在打开应用之前打开了手机的位置，所以这不是问题所在。我要说的另一件事是，所有的计算都没问题，而且工作正常。
答案 0 :(得分：3)
在Android 6.0 (API level 23）及更高版本，您需要在运行时请求ACCESS_COARSE_LOCATION和ACCESS_FINE_LOCATION的权限。见Requesting Permissions at Run Time。可能就是这种情况。
答案 1 :(得分：1)
最好的办法是记录问题并对其进行回溯，这样你就可以看到它变坏的地方或者至少有一个线索。如果user35603的答案不起作用，那么试试这个并发布关于你的问题的logcat部分。
答案 2 :(得分：0)
最后问题解决了！这部分代码遇到了麻烦：
Location location = locationManager.getLastKnownLocation(provider);
text.setText(location.getLatitude()+"");
text2.setText(location.getLongitude()+"");
我想 location 需要一点时间来获取当前位置。实际上，当app想要运行下面的行时，location仍为null并且应用程序崩溃：
text1.setText(location.getLatitude()+"");
我用这样的东西解决了崩溃：
Location location = locationManager.getLastKnownLocation(provider);
while(location==null){}
text.setText(location.getLatitude()+"");
text2.setText(location.getLongitude() + "");
text3.setText(distanceBetweenMeter(azadiSquare,location)+"");
崩溃已解决，但应用程序冻结了白屏。我不确切地知道，但我猜它被困在 while 循环中。谢谢！
答案 3 :(得分：0)
public class MainActivity extends AppCompatActivity {
pb=findViewById(R.id.progressbar);
Example ex=new Example();//The subclass object is created here
boolean stop=false;//a boolean variable to start or stop the thread to get location.
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (location== null) {
showSettingDialog();//this will show your custom way of displaying
//the location setting intent
new Thread(ex).start();//here the fetching location gets started
}
else{
//here write code after your location is fetched
//here to got some other base activity or stay in this
finish();//if you wan to stay in this activity then omit this line.
}
}
public class Example implements Runnable{ //This is a sub class in your main activity.
@Override
public void run() {//overriding run medthod
try {
while(location==null) { //this part keeps on running whithout
//ui freeze
if (stop) {
return;
}
runOnUiThread(new Runnable() {
@Override
public void run() {
pb.setVisibility(View.VISIBLE);
}
});
getLastLocation();//this function will fetch location.
Thread.sleep(1500);
pb.setVisibility(View.INVISIBLE);
if (location != null) {
//do your code here
stop = true;
finish();
}
}
}
catch(InterruptedException e){
e.printStackTrace();
}
}
}
}