BRVAH配合databinding完成超级简单的列表适配器

我以前一直使用BRVAH的adapter,非常好用,搭配databinding后,要是能够在convert中可以直接拿到对应的ViewDataBinding的话,我们的adapter就可以像如下这样

@Override
    protected void convert(MVViewHolder helper, MyEntry item) {
        helper.getDataViewBinding().setItem(item);
    }

对具体的显示,在xml中完成,就这么一句话就可以完成整个adapter展示内容的绑定了,非常方便
,我们的绑定过程在我们自定义的viewholder中完成,它需要继承BRVAH的BaseViewHolder,贴代码

public class MVViewHolder extends BaseViewHolder {
    T binding = null;

    public MVViewHolder(T binding) {
        super(binding.getRoot());
        binding.getRoot().setLayoutParams(new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));
        this.binding = binding;
    }

    public BaseViewHolder setQAdapter(BaseQuickAdapter adapter) {
        super.setAdapter(adapter);
        return this;
    }

    public T getDataViewBinding() {
        return this.binding;
    }

}

构造函数通过传入对应的viewdatabinding来绑定,其中设置layoutparams是我在解决scrollview嵌套recycleview的过程中,出现展示一行解决的过程中,通过构建binding的时候不传入parent参数出现recycleview的item条目不能充满父控件而写的,大家可以根据自己的情况改动,setQAdapter后面会用,先不用管

接下来是最重要的自定义的adapter,先放代码

public abstract class BaseQAdapter extends BaseQuickAdapter {
    public BaseQAdapter(int layoutResId, @Nullable List data) {
        super(layoutResId, data);
    }

    public BaseQAdapter(@Nullable List data) {
        super(data);
    }

    public BaseQAdapter(int layoutResId) {
        super(layoutResId);
    }

    @Override
    public K onCreateViewHolder(ViewGroup parent, int viewType) {
        if (viewType != LOADING_VIEW && viewType != HEADER_VIEW && viewType != EMPTY_VIEW && viewType != FOOTER_VIEW) {
            D d = DataBindingUtil.inflate(LayoutInflater.from(parent.getContext()), this.mLayoutResId, null, false);
            d.executePendingBindings();
            MVViewHolder mvViewHolder = new MVViewHolder(d);
            bindViewClickListener(mvViewHolder);
            mvViewHolder.setQAdapter(this);
            return (K) mvViewHolder;
        } else {
            return super.onCreateViewHolder(parent, viewType);
        }
    }


    private void bindViewClickListener(final BaseViewHolder baseViewHolder) {
        if (baseViewHolder == null) {
            return;
        }
        final View view = baseViewHolder.itemView;
        if (view == null) {
            return;
        }
        if (getOnItemClickListener() != null) {
            view.setOnClickListener(v -> getOnItemClickListener().onItemClick(BaseQAdapter.this, v, baseViewHolder.getLayoutPosition() - getHeaderLayoutCount()));
        }
        if (getOnItemLongClickListener() != null) {
            view.setOnLongClickListener(v -> getOnItemLongClickListener().onItemLongClick(BaseQAdapter.this, v, baseViewHolder.getLayoutPosition() - getHeaderLayoutCount()));
        }
    }
}

构造函数和父类一样,没有改变,重要的是onCreateViewHolder中,为了看清楚为什么这样写,我们先看下父类中的onCreateViewHolder是怎么写的

@Override
    public K onCreateViewHolder(ViewGroup parent, int viewType) {
        K baseViewHolder = null;
        this.mContext = parent.getContext();
        this.mLayoutInflater = LayoutInflater.from(mContext);
        switch (viewType) {
            case LOADING_VIEW:
                baseViewHolder = getLoadingView(parent);
                break;
            case HEADER_VIEW:
                baseViewHolder = createBaseViewHolder(mHeaderLayout);
                break;
            case EMPTY_VIEW:
                baseViewHolder = createBaseViewHolder(mEmptyLayout);
                break;
            case FOOTER_VIEW:
                baseViewHolder = createBaseViewHolder(mFooterLayout);
                break;
            default:
                baseViewHolder = onCreateDefViewHolder(parent, viewType);
                bindViewClickListener(baseViewHolder);
        }
        baseViewHolder.setAdapter(this);
        return baseViewHolder;

    }

可以看出,在BRVAH中的view ,主要包含的几种类型,LOADING_VIEW,HEADER_VIEW,EMPTY_VIEW,FOOTER_VIEW, 分别在这里创建了viewholder,而我们关心的仅仅只是当中我们自己的view,因此在其他的地方,我返回的是super,接下来就是通过构造把我们的binding传进去,并把adapter以及一些点击事件绑定,记得一定要绑定,不绑定点击事件的话点击事件无效,不绑定adapter的话会导致父类其他地方通过adapter找view的时候,出现空指针,弄好后看下超级简单的具体用法

新建xml item_demo.xml

adapter

public class MyDemoAdapter extends BaseQAdapter> {
    public MyDemoAdapter(@Nullable List data) {
        super(R.layout.item_demo, data);
    }

    @Override
    protected void convert(MVViewHolder helper, String item) {
        helper.getDataViewBinding().setName(item);
        helper.addOnClickListener(R.id.name);
    }
}

再搭配databinding的属性设置,看下我们的recycleview

这样就基本完成了,当然,这只是对basequickadapter的一个写法,brvah的其他功能adapter也可以按着这个思路写就好了