MultipleItemRvAdapter 自定义BaseViewHolder出现强转异常的问题

[K-Hector]

异常信息：
java.lang.ClassCastException: com.chad.library.adapter.base.BaseViewHolder cannot be cast to adapter.itemprovider.SmallContentViewHolder
at adapter.itemprovider.IPCommercialDetailSmallContent.convert(IPCommercialDetailSmallContent.java:21)
at com.chad.library.adapter.base.MultipleItemRvAdapter.convert(MultipleItemRvAdapter.java:70)
at com.chad.library.adapter.base.BaseQuickAdapter.onBindViewHolder(BaseQuickAdapter.java:951)
at com.chad.library.adapter.base.BaseQuickAdapter.onBindViewHolder(BaseQuickAdapter.java:68)
at android.support.v7.widget.RecyclerView$Adapter.onBindViewHolder(RecyclerView.java:6476)

这是其中一种类型的

这是另一种类型的：

适配器代码类型指定为了BaseViewHolder：

断点后异常出现的位置是在MultipleItemRvAdapter中的convert()方法中：

感觉这样强转一定会出错的吧？

[K-Hector]

问题解决了，重写onCreateDefViewHolder(ViewGroup parent, int viewType)方法,，反射用的字节码对象应该拿BaseItemProvider上的

@Override
protected V onCreateDefViewHolder(ViewGroup parent, int viewType) {
    int layoutId = mLayoutResId;
    if (getMultiTypeDelegate() != null) {
        layoutId = getMultiTypeDelegate().getLayoutId(viewType);
    }
    View view = getItemView(layoutId, parent);

    Class temp = mItemProviders.get(viewType).getClass();
    Class z = null;
    while (z == null && null != temp) {
        z = getInstancedGenericKClass(temp);
        temp = temp.getSuperclass();
    }
    V k;
    // 泛型擦除会导致z为null
    if (z == null) {
        k = (V) new BaseViewHolder(view);
    } else {
        k = createGenericKInstance(z, view);
    }
    return k != null ? k : (V) new BaseViewHolder(view);
}

protected Class getInstancedGenericKClass(Class z) {
    Type type = z.getGenericSuperclass();
    if (type instanceof ParameterizedType) {
        Type[] types = ((ParameterizedType) type).getActualTypeArguments();
        for (Type temp : types) {
            if (temp instanceof Class) {
                Class tempClass = (Class) temp;
                if (BaseViewHolder.class.isAssignableFrom(tempClass)) {
                    return tempClass;
                }
            } else if (temp instanceof ParameterizedType) {
                Type rawType = ((ParameterizedType) temp).getRawType();
                if (rawType instanceof Class && BaseViewHolder.class.isAssignableFrom((Class<?>) rawType)) {
                    return (Class<?>) rawType;
                }
            }
        }
    }
    return null;
}

protected V createGenericKInstance(Class z, View view) {
    try {
        Constructor constructor;
        // inner and unstatic class
        if (z.isMemberClass() && !Modifier.isStatic(z.getModifiers())) {
            constructor = z.getDeclaredConstructor(getClass(), View.class);
            constructor.setAccessible(true);
            return (V) constructor.newInstance(this, view);
        } else {
            constructor = z.getDeclaredConstructor(View.class);
            constructor.setAccessible(true);
            return (V) constructor.newInstance(view);
        }
    } catch (NoSuchMethodException e) {
        e.printStackTrace();
    } catch (IllegalAccessException e) {
        e.printStackTrace();
    } catch (InstantiationException e) {
        e.printStackTrace();
    } catch (InvocationTargetException e) {
        e.printStackTrace();
    }
    return null;
}