Re: [scala] Scalandroid

> One more thing: it works if Foo is a trait or an abstract class.
>
> Ingo
>
> Ingo Maier wrote:
>> It looks like it has problems with invokespecial and super. The
>> following will work:
>>
>> Java:
>>
>> public class MyActivity extends Activity
>> {
>>     /** Called with the activity is first created. */
>>     @Override
>>     public void onCreate(Bundle icicle)
>>     {
>>         super.onCreate(icicle);
>>         new Sub().f(this);
>>     }
>> }
>>
>> Scala:
>>
>> class Foo {
>>   def g(a: Activity) {
>>     val tv = new TextView(a)
>>     tv.setText("Hello Android. Cheers, Scala")
>>     a.setContentView(tv)
>>   }
>> }
>>
>> class Sub extends Foo {
>>   def f(a: Activity) { g(a) }
>> }
>>
>> If I replace the call to g with an explicit super reference, i.e.,
>>
>> class Sub extends Foo {
>>   def f(a: Activity) { super.g(a) }
>> }
>>
>> I get a NoSuchMethodError at runtime:
>>
>> E/AndroidRuntime(545): Caused by: java.lang.NoSuchMethodError: g
>> E/AndroidRuntime(545): at my.test.Sub.f(MyActivity.scala:26)
>> E/AndroidRuntime(545): at my.test.MyActivity.onCreate(MyActivity.java:14)
>> E/AndroidRuntime(545): at
>> android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:786)
>>
>> E/AndroidRuntime(545): at
>> android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1367)
>>
>> E/AndroidRuntime(545): ... 11 more
>>
>>
>> The only difference of the generated bytecode I can see from javap's
>> output is a different constant pool and that it uses invokespecial
>> instead of invokevirtual in f. Invokespecial is also used if I move g
>> to Sub and make it private, but it works that way.
>>
>> Just wanted to share my results. Anyone else playing with it?
>>
>> Ingo
>>
>>
>> Matt Hellige wrote:
>>> On Nov 13, 2007 2:52 PM, martin odersky
>>> <odersky@...> wrote:
>>>> Matt,
>>>>
>>>>> with my own classes. This fixed the NoClassDefFoundError, but now I
>>>>> get something worse. The onCreate() method of each activity must call
>>>>> super.onCreate(). The phone checks for this and throws an exception
>>>>> otherwise. But if I try to call super.onCreate() in my Scala code,  I
>>>>> get a NoClassDefFoundError.
>>>> It would be good to find out more about this. Certainly, Android would
>>>> be a great target for Scala programs if we could get it to work. Can
>>>> you give more details about the error your encountered? Which class
>>>> was not found?
>>>
>>> Sorry, that was a typo. I meant to say that I get a NoSuchMethodError,
>>> trying to call the superclass definition of onCreate(). (I realize
>>> that that's not especially helpful.) If I have time, I will try to get
>>> back to this later and find out more info. I think getting details
>>> will require setting up the Android debugging environment a little
>>> more carefully.
>>>
>>> m
>>>
>>
>
>