Androidスタジオエラー：致命的な例外：main（java.lang.IllegalStateException：android：onClickのメソッドを実行できませんでした）

Question

私は走行距離を追跡するランニング/フィットネスアプリケーションをコーディングしています。 Android Studioでは正常に表示されますが、アプリケーションを実行するといくつかのエラーが発生します。

 public class MapsActivity extends FragmentActivity implements OnMapReadyCallback, GoogleApiClient.ConnectionCallbacks, 
    GoogleApiClient.OnConnectionFailedListener, LocationListener { 

private GoogleMap mMap; 
private GoogleApiClient mGoogleApiClient; 
public static final String TAG = "FitnessApp"; 
private LocationRequest mLocationRequest; 
public LatLng latLng, latLngStart; 
public Pair pair; 
Handler Handler = new Handler(); 
private long startTime, elapsedTime; 
private final int REFRESH_RATE = 100; 
private String hours, minutes, seconds; 
private long secs, mins, hrs; 
private boolean stopped = false; 
public int dist; 
public int Speed; 

@Override 
protected void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.activity_maps); 
    // Obtain the SupportMapFragment and get notified when the map is ready to be used. 
    SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager() 
      .findFragmentById(R.id.map); 
    mapFragment.getMapAsync(this); 
    mGoogleApiClient = new GoogleApiClient.Builder(this) 
      .addConnectionCallbacks(this) 
      .addOnConnectionFailedListener(this) 
      .addApi(LocationServices.API) 
      .build(); 
    mLocationRequest = LocationRequest.create() 
      .setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY) 
      .setInterval(10 * 1000)  // 10 seconds, in milliseconds 
      .setFastestInterval(1 * 1000); // 1 second, in milliseconds 
} 

@Override 
public void onMapReady(GoogleMap googleMap) { 
    mMap = googleMap; 
    latLng = new LatLng (1.3263, 103.8026); 
    mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng)); 
    mMap.animateCamera(CameraUpdateFactory.zoomTo(11)); 
} 

@Override 
public void onConnected(@Nullable Bundle bundle) { 
    Log.i(TAG, "Location services connected."); 
    Location location = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient); 
    if (location == null) { 
     if (ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, android.Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) { 
      return; 
     } 
     LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient, mLocationRequest, this); 
    } else { 
     handleNewLocation(location); 
    } 
} 

@Override 
public void onConnectionSuspended(int i) { 
    Log.i(TAG, "Location services suspended. Please reconnect."); 
} 

@Override 
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) { 
    if (connectionResult.hasResolution()) { 
     try { 
      // Start an Activity that tries to resolve the error 
      connectionResult.startResolutionForResult(this, CAUSE_SERVICE_DISCONNECTED); 
     } catch (IntentSender.SendIntentException e) { 
      e.printStackTrace(); 
     } 
    } else { 
     Log.i(TAG, "Location services connection failed with code " + connectionResult.getErrorCode()); 
    } 
} 

@Override 
protected void onResume() { 
    super.onResume(); 
    mGoogleApiClient.connect(); 
} 

@Override 
protected void onPause() { 
    super.onPause(); 
    if (mGoogleApiClient.isConnected()) { 
     LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient, this); 
     mGoogleApiClient.disconnect(); 
    } 
} 

@Override 
public void onLocationChanged(Location location) { 
    handleNewLocation(location); 
} 

public LatLng handleNewLocation(Location location) { 
    Log.d(TAG, location.toString()); 
    double currentLatitude = location.getLatitude(); 
    double currentLongitude = location.getLongitude(); 
    latLng = new LatLng(currentLatitude,currentLongitude); 
    MarkerOptions options = new MarkerOptions() 
      .position(latLng) 
      .title("You are here!"); 
    options.icon(BitmapDescriptorFactory.defaultMarker(BitmapDescriptorFactory.HUE_MAGENTA)); 
    mMap.addMarker(options); 
    mMap.moveCamera(CameraUpdateFactory.newLatLng(latLng)); 
    mMap.animateCamera(CameraUpdateFactory.zoomTo(11)); 
    return latLng; 
} 

public void startClick(View view) { 
    showStopButton(); 
    if(stopped){ 
     startTime = System.currentTimeMillis() - elapsedTime; 
    } 
    else{ 
     startTime = System.currentTimeMillis(); 
    } 
    Handler.removeCallbacks(startTimer); 
    Handler.postDelayed(startTimer, 0); 
    h1.removeCallbacks(startCalorieTracker); 
    h1.postDelayed(startCalorieTracker,0); 
    latLngStart = new LatLng (latLng.latitude,latLng.longitude); 
} 

public void stopClick(View view) { 
    Double lat1 = latLngStart.latitude; 
    Double lon1 = latLngStart.longitude; 
    Double lat2 = latLng.latitude; 
    Double lon2 = latLng.longitude; 
    getDistance(lat1, lon1, lat2, lon2); 
    hideStopButton(); 
    Handler.removeCallbacks(startTimer); 
    h1.removeCallbacks(startCalorieTracker); 
    stopped = true; 
    ((TextView)findViewById(R.id.distance)).setText(dist); 
    if (hrs > 0 || mins > 0 || secs >0) { 
     Speed = dist/(Integer.parseInt(hours)+(Integer.parseInt(minutes)/60)+(Integer.parseInt(seconds)/3600)); 
     ((TextView)findViewById(R.id.speed)).setText(Speed + "km/h"); 
    } 
    else { 
     ((TextView)findViewById(R.id.speed)).setText("0 km/h"); 
    } 
} 

public void resetClick(View view) { 
    stopped = false; 
    ((TextView)findViewById(R.id.time)).setText("00:00:00"); 
    ((TextView)findViewById(R.id.distance)).setText("0 km"); 
    ((TextView)findViewById(R.id.speed)).setText("0 km/h"); 
    ((TextView)findViewById(R.id.calories)).setText("0 Cal"); 
} 

public int getDistance(double lat1, double lon1, double lat2, double lon2) { 
    double latA = Math.toRadians(lat1); 
    double lonA = Math.toRadians(lon1); 
    double latB = Math.toRadians(lat2); 
    double lonB = Math.toRadians(lon2); 
    double cosAng = (Math.cos(latA) * Math.cos(latB) * Math.cos(lonB - lonA)) + 
      (Math.sin(latA) * Math.sin(latB)); 
    double ang = Math.acos(cosAng); 
    double dist = ang * 6371; 
    return (int) dist; 
} 

private void showStopButton(){ 
    findViewById(R.id.buttonStart).setVisibility(View.GONE); 
    findViewById(R.id.buttonReset).setVisibility(View.GONE); 
    findViewById(R.id.buttonStop).setVisibility(View.VISIBLE); 
} 

private void hideStopButton(){ 
    findViewById(R.id.buttonStart).setVisibility(View.VISIBLE); 
    findViewById(R.id.buttonReset).setVisibility(View.VISIBLE); 
    findViewById(R.id.buttonStop).setVisibility(View.GONE); 
} 

//Timer 
private Runnable startTimer = new Runnable() { 
    public void run() { 
     elapsedTime = System.currentTimeMillis() - startTime; 
     updateTimer(elapsedTime); 
     Handler.postDelayed(this,REFRESH_RATE); 
    } 
}; 

private void updateTimer (float time){ 
    secs = (long)(time/1000); 
    mins = (long)((time/1000)/60); 
    hrs = (long)(((time/1000)/60)/60); 

    secs = secs % 60; 
    seconds=String.valueOf(secs); 
    if(secs == 0){ 
     seconds = "00"; 
    } 
    if(secs <10 && secs > 0){ 
     seconds = "0"+seconds; 
    } 

    mins = mins % 60; 
    minutes=String.valueOf(mins); 
    if(mins == 0){ 
     minutes = "00"; 
    } 
    if(mins <10 && mins > 0){ 
     minutes = "0"+minutes; 
    } 

    hours=String.valueOf(hrs); 
    if(hrs == 0){ 
     hours = "00"; 
    } 
    if(hrs <10 && hrs > 0){ 
     hours = "0"+hours; 
    } 

    ((TextView)findViewById(R.id.time)).setText(hours + ":" + minutes + ":" + seconds); 
} 

public Handler h1= new Handler(); 
public Runnable startCalorieTracker = new Runnable() { 

    @Override 
    public void run() { 
     h1.postDelayed(this, REFRESH_RATE); 
     int CaloriesBurnt = dist*85; 
     ((TextView)findViewById(R.id.calories)).setText(CaloriesBurnt + "Cal"); 
    } 
}; 

私が取得エラー：ここにコードがある

FATAL EXCEPTION: main 
                    Process: rainbow.com.fitnessapp3, PID: 3268 
                    java.lang.IllegalStateException: Could not execute method for android:onClick 
                     at android.view.View$DeclaredOnClickListener.onClick(View.java:4452) 
                     at android.view.View.performClick(View.java:5198) 
                     at android.view.View$PerformClick.run(View.java:21147) 
                     at android.os.Handler.handleCallback(Handler.java:739) 
                     at android.os.Handler.dispatchMessage(Handler.java:95) 
                     at android.os.Looper.loop(Looper.java:148) 
                     at android.app.ActivityThread.main(ActivityThread.java:5417) 
                     at java.lang.reflect.Method.invoke(Native Method) 
                     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726) 
                     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616) 
                    Caused by: java.lang.reflect.InvocationTargetException 
                     at java.lang.reflect.Method.invoke(Native Method) 
                     at android.view.View$DeclaredOnClickListener.onClick(View.java:4447) 
                     at android.view.View.performClick(View.java:5198)  
                     at android.view.View$PerformClick.run(View.java:21147)  
                     at android.os.Handler.handleCallback(Handler.java:739)  
                     at android.os.Handler.dispatchMessage(Handler.java:95)  
                     at android.os.Looper.loop(Looper.java:148)  
                     at android.app.ActivityThread.main(ActivityThread.java:5417)  
                     at java.lang.reflect.Method.invoke(Native Method)  
                     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)  
                     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)  
                    Caused by: android.content.res.Resources$NotFoundException: String resource ID #0x0 
                     at android.content.res.Resources.getText(Resources.java:312) 
                     at android.widget.TextView.setText(TextView.java:4417) 
                     at rainbow.com.fitnessapp3.MapsActivity.stopClick(MapsActivity.java:175) 
                     at java.lang.reflect.Method.invoke(Native Method)  
                     at android.view.View$DeclaredOnClickListener.onClick(View.java:4447)  
                     at android.view.View.performClick(View.java:5198)  
                     at android.view.View$PerformClick.run(View.java:21147)  
                     at android.os.Handler.handleCallback(Handler.java:739)  
                     at android.os.Handler.dispatchMessage(Handler.java:95)  
                     at android.os.Looper.loop(Looper.java:148)  
                     at android.app.ActivityThread.main(ActivityThread.java:5417)  
                     at java.lang.reflect.Method.invoke(Native Method)  
                     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:726)  
                     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:616)  

私はこの問題は、次のコード行であると思う：

public void startClick(View view) { 
    showStopButton(); 
    if(stopped){ 
     startTime = System.currentTimeMillis() - elapsedTime; 
    } 
    else{ 
     startTime = System.currentTimeMillis(); 
    } 
    Handler.removeCallbacks(startTimer); 
    Handler.postDelayed(startTimer, 0); 
    h1.removeCallbacks(startCalorieTracker); 
    h1.postDelayed(startCalorieTracker,0); 
    latLngStart = new LatLng (latLng.latitude,latLng.longitude); 
} 

public void stopClick(View view) { 
    Double lat1 = latLngStart.latitude; 
    Double lon1 = latLngStart.longitude; 
    Double lat2 = latLng.latitude; 
    Double lon2 = latLng.longitude; 
    getDistance(lat1, lon1, lat2, lon2); 
    hideStopButton(); 
    Handler.removeCallbacks(startTimer); 
    h1.removeCallbacks(startCalorieTracker); 
    stopped = true; 
    ((TextView)findViewById(R.id.distance)).setText(dist); 
    if (hrs > 0 || mins > 0 || secs >0) { 
     Speed = dist/(Integer.parseInt(hours)+(Integer.parseInt(minutes)/60)+(Integer.parseInt(seconds)/3600)); 
     ((TextView)findViewById(R.id.speed)).setText(Speed + "km/h"); 
    } 
    else { 
     ((TextView)findViewById(R.id.speed)).setText("0 km/h"); 
    } 
} 

Answer 1

問題はここにある：

公開void handleNewLocation（所在地）

あなたのメソッドは無効なので、実行すると値は返されません。それが好き

public Pair<String, String> handleNewLocation(Location location){ 
//do your thing here 
[...] 
Pair<String, String> pair = new Pair<>(); 
pair.first = Double.toString(currentLatitude); 
pair.second = Double.toString(currentLongitude); 
return pair; 
} 

そして、あなたはその方法を使用する必要がある場合、使用を：：

を

最も簡単な解決策は、このように、2つの値を返すために、ペアオブジェクトを使用することです

Pair pair = handleNewLocation(Location location); 
String firstValue = pair.first; //THIS IS THE FIRST VALUE 
String secondValue = pair.second; //THIS IS THE SECOND VALUE 

これを行うもう1つの方法は、値を保持するカスタムオブジェクト「POJO」を作成することです。 POJOを作成する方法を調べると、Javaプログラミングを開始するかどうかを知ることは面白くて、有益であり、有益です。

また、必要がない限り、メソッドを「パブリック」にしないでください。あなたが書き込まれているクラスでのみメソッドを使用している場合は、それを "プライベート"にすることができます。これは、アプリケーションを安全に保護するために行うことをお勧めします。