Question

当我运行此代码时，它会崩溃而没有任何错误。我已经尝试了我所知道的一切并完成了搜索，但我可以想出这个。它构建并运行良好，一直到FleetCapacity中的cout，关于该行的一些事情正在使代码崩溃。当我注释掉那行代码运行正常，所以我不确定为什么这行代码导致我的程序崩溃和刻录。

#include <iostream>
#include <string>
using namespace std;

class Ship{
private:
    string shipName;
    string shipYear;
public:
    Ship(string sN,string sY){shipName=sN; shipYear=sY;}
    virtual void printInfo();
    void setShipName(string);
    virtual string getShipName();
    void setShipYear(string);
    string getShipYear();
};

class CruiseShip:public Ship{
private:
    int maxPass;
    int maxCrew;
public:
    CruiseShip(string sN,string sY, int mP,int mC):Ship(sN,sY){setShipName(sN);maxPass=mP; maxCrew=mC; }
    void printInfo();
    void setMaxPass(int);
    int getMaxPass();
    void setMaxCrew(int);
    int getMaxCrew();
};

class CargoShip:public Ship{
private:
    int cargoCap;
public:
    CargoShip(string sN,string sY,int cC):Ship(sN,sY){setShipName(sN);cargoCap=cC;}
    void printInfo();
    void setCargoCap(int);
    int getCargoCap();

};


void Ship::setShipName(string sN){shipName=sN;}
string Ship::getShipName(){return shipName;}
void Ship::setShipYear(string sN){shipYear=sN;}
string Ship::getShipYear(){return shipYear;}
void Ship::printInfo(){
cout<<"The ships name is "<<shipName<<endl;
cout<<"The ships year is "<<shipYear<<endl;
}

void CruiseShip::printInfo(){
cout<<"The ships name is "<<getShipName()<<endl;
cout<<"The ships maximum passangers is "<<maxPass<<endl;
}
void CruiseShip::setMaxPass(int mP){maxPass=mP;}
int CruiseShip::getMaxPass(){return maxPass;}
void CruiseShip::setMaxCrew(int mC){maxCrew=mC;}
int CruiseShip::getMaxCrew(){return maxCrew;}

void CargoShip::printInfo(){
cout<<"The ships name is "<<getShipName()<<endl;
cout<<"The ships cargo capacity is "<<cargoCap<<endl;
}
int CargoShip::getCargoCap(){return cargoCap;}
void CargoShip::setCargoCap(int cC){cargoCap=cC;}




void fleetCapacity(Ship** s ,int e){

    cout << "Name of ship: " << s[e]->getShipName() << endl;


}

int main()
{
    const int NUMSHIPS = 3;
    //int aSize = NUMSHIPS;
    // array of ship pointers initialized with addresses of dynamically allocated class objects.
    Ship *ships[NUMSHIPS] = {
                                         new Ship("The Dinghy Berry", "1982"),
                                         new CruiseShip("Disney Adventure Tours"," ",500,100),
                                         new CargoShip("The Sea Trucker"," ", 50)

                                       };

    for (int i = 0; i < NUMSHIPS; i++ )
    {
        ships[i]->printInfo();
    }

   cout << "The entire fleet capacity is: ";
   fleetCapacity(ships, NUMSHIPS);
    cout << " tons." << endl;
    return 0;
}

Answer 1

您正在调用getLocation，然后在该函数中访问private ArrayList<Double> getLocation() { LocationManager locationManager = (LocationManager) this.getSystemService(Context.LOCATION_SERVICE); if(isLocationEnabled(locationManager)){ Location location = locationManager.getLastKnownLocation(LocationManager.NETWORK_PROVIDER); ArrayList<Double> values = new ArrayList<>(); double latitude = location.getLatitude(); double longitude = location.getLongitude(); values.add(latitude); values.add(longitude); return values; } else if(!isLocationEnabled(locationManager)){ Log.d("LOCATION IS NOT ENABLED", "locatoin not enabled"); AlertDialog.Builder builder = new AlertDialog.Builder(MainActivity.this); builder.setMessage("Turn on location and click \"OK") .setPositiveButton("OK", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { getLocation(); } }); AlertDialog dialog = builder.create(); dialog.show(); } return null; } private boolean isLocationEnabled(LocationManager lm){ boolean gps = lm.isProviderEnabled(LocationManager.GPS_PROVIDER); boolean network = lm.isProviderEnabled(LocationManager.NETWORK_PROVIDER); if(!gps && !network){ return false; } else { return true; } }（fleetCapacity(ships, NUMSHIPS);）。有效索引为s[e]到ships[NUMSHIPS]。

将指向对象数组的指针传递给函数

1 个答案: