JNA Objective-C (Rococoa)日历回调

Question

我想通过Rococoa访问Java中的Objective-C EKEventStore。API指定了一个callback，当用户接受日历访问提示时将得到通知，这在纯Objective-C中工作得很好。

    Native.loadLibrary("EventKit", EventKitLibrary.class);

    EKEventStore store = EKEventStore.CLASS.alloc();
    store.init();
    //store = store.initWithAccessToEntityTypes(EKEntityType.EKEntityTypeEvent); // no notification
    EKEventStoreRequestAccessCompletionHandler handler = new EKEventStoreRequestAccessCompletionHandler() {
        @Override
        public void invoke(boolean granted, Pointer error) {
            System.out.println("Access: " + granted);
            NSArray calArray = store.calendarsForEntityType(EKEntityType.EKEntityTypeEvent);
            for (int i = 0; i < calArray.count(); i++) {
                NSObject calObject = calArray.objectAtIndex(i);
                EKCalendar osxcal = Rococoa.cast(calObject, EKCalendar.class);
                System.out.println(osxcal.title().toString());
            }
        }

    };
    ObjCObject object = Rococoa.proxy(handler); // get Objective C Callback Object to send
    store.requestAccessToEntityType_completion(EKEntityType.EKEntityTypeEvent, object.id());

    try {
        Thread.sleep(10000); // wait for the access prompt
    } catch (InterruptedException ex) {
    }

    // random object access to save instances from gc
    System.out.println(handler.toString());
    System.out.println(store.id());
    System.out.println(object.id());

图书馆

public interface EventKitLibrary extends Library {

    public static EventKitLibrary INSTANCE = (EventKitLibrary) Native.loadLibrary("EventKit", EventKitLibrary.class);

}

映射的类

public abstract class EKEventStore extends NSObject {

    public static final _Class CLASS = Rococoa.createClass("EKEventStore", _Class.class);

    public interface _Class extends ObjCClass {

        public abstract EKEventStore alloc();
    }

    public static interface EKEntityType {

        public static final int EKEntityTypeEvent = 0;
        public static final int EKEntityTypeReminder = 1;
    };

    public static interface EKEntityMask {

        public static final int EKEntityMaskEvent = (1 << EKEntityType.EKEntityTypeEvent);
        public static final int EKEntityMaskReminder = (1 << EKEntityType.EKEntityTypeReminder);
    };

    public abstract EKEventStore initWithAccessToEntityTypes(int EKEntityMask);

    public abstract EKEventStore init();

    public abstract void requestAccessToEntityType_completion(int EKEntityType, ID handler);

    interface EKEventStoreRequestAccessCompletionHandler {

        void invoke(boolean granted, Pointer error);
    }

    public abstract NSArray calendarsForEntityType(int EKEntityType);
}


public abstract class EKCalendar extends NSObject {

    public static final _Class CLASS = Rococoa.createClass("EKCalendar", _Class.class);

    public static interface _Class extends ObjCClass {

        public NSObject alloc();
    }

    public abstract NSString title();
}

对于缺少的NSError参数的类型转换，我只得到了一个IllegalArgumentException。是我做错了什么，还是我应该实现一个TypeConverter？如果，我该怎么做呢？

编辑：

现在我使用指针而不是NSError作为回调函数的参数，并得到以下JVM-Crash。

EDIT2：

现在，我使用Rococoa.proxy(处理程序)函数进行回调，就像在Rococoa库中一样。出现输入提示，但是回调函数没有被调用。我认为我的回调初始化仍然是错误的。

Answer 1

通常，TypeMapper是这样实现的，它将Pointer原生类型转换为其他一些Java类型：

class NSErrorTypeMapper extends DefaultTypeMapper {
    public NSErrorTypeMapper() {
        TypeConverter tc = new TypeConverter() {
            public Object toNative(Object value, ToNativeContext ctxt) {
                Pointer p = // convert your NSError "value" into a Pointer
                return p;
            }
            public Object fromNative(Object value, FromNativeContext ctxt) {
                Pointer p = (Pointer)value;
                Object object = // convert the pointer into an NSError object
                return object;    
            }
            public class nativeType() {
                return Pointer.class;
            }
        };
        addToNativeConverter(NSError.class, tc);
        addFromNativeConverter(NSError.class, tc);
    }
}