android - setImageResource 到可绘制对象数组会抛出空指针异常

Question

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.view_orbital);
    Intent i = getIntent();
    Integer[] orbitalBodies = {R.drawable.dres, R.drawable.duna, R.drawable.eeloo, R.drawable.eve, R.drawable.jool, R.drawable.kerbin, R.drawable.kerbol, R.drawable.moho};
    int planetId = i.getExtras().getInt("intOrbitalId");
    ImageView img = (ImageView)findViewById(R.id.image);
    img.setImageResource(orbitalBodies[planetId]); //this throws nullpointerexception
}

在调试中，我能够确认 orbitalBodies[planetId] 为可绘制对象返回了正确的整数值。我无法克服这个小问题

Answer 1

使用 int 数组代替 Integer 数组

int[] orbitalBodies = {R.drawable.dres, R.drawable.duna, R.drawable.eeloo, R.drawable.eve, R.drawable.jool, R.drawable.kerbin, R.drawable.kerbol, R.drawable.moho};
int planetId = getIntent.getExtras().getInt("intOrbitalId");

if(planetId != null) {
    ImageView img = (ImageView)findViewById(R.id.image);
    img.setImageResource(orbitalBodies[planetId]);
}

因为

public static final class drawable 
{
        public static final int ic_launcher=0x7f020000;
}