[英]android - java.lang.RuntimeException
Why am I getting an java.lang.runtimeexception: Unable to instantiate activityComponentInfo {com.example.carprofile/com.example.carprofile.CarRegistraion}: java.lang.NullPointerExceprion 为什么我得到java.lang.runtimeexception:无法实例化activityComponentInfo {com.example.carprofile / com.example.carprofile.CarRegistraion}:java.lang.NullPointerExceprion
This is my code: 这是我的代码:
public class CarRegistration extends Activity{
//ParseXML parseClass;
Button saveCar;
EditText carMake = (EditText) findViewById(R.id.etCarMake);
EditText carModel = (EditText) findViewById(R.id.etCarModel);
String newCar;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.car_registration);
saveCar = (Button) findViewById(R.id.bSaveCar);
saveCar.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
newCar = carMake.getText() +" "+ carModel.getText();
//parseClass = new ParseXML(newCar);
//parseClass.editXML();
}
});
}
if I clear the onCreate method, from saveCar = (Button)..., everything works fine. 如果我从saveCar =(Button)...中清除onCreate方法,则一切正常。
Can someone tell me what am I doing wrong? 有人可以告诉我我在做什么错吗?
Try this, 尝试这个,
public class CarRegistration extends Activity{
Button saveCar;
String newCar;
@Override
protected void onCreate(Bundle savedInstanceState) {
// TODO Auto-generated method stub
super.onCreate(savedInstanceState);
setContentView(R.layout.car_registration);
EditText carMake = (EditText) findViewById(R.id.etCarMake); //these lines should be after setContentView()
EditText carModel = (EditText) findViewById(R.id.etCarModel);
saveCar = (Button) findViewById(R.id.bSaveCar);
saveCar.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
newCar = carMake.getText() +" "+ carModel.getText();
//parseClass = new ParseXML(newCar);
//parseClass.editXML();
}
});
} }
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