想让RecycleView的代码更简洁吗？ 那就使用DataBinding吧~~
DataBinding可以直接将数据和View绑定 具体可以看一下layout文件
recycleView的layout
<layout xmlns:android="http://schemas.android.com/apk/res/android">
<data>
</data>
<android.support.v7.widget.RecyclerView
android:id="@+id/stu_recycle_view"
android:layout_width="match_parent"
android:layout_height="match_parent" />
</layout>
item的layout
<layout xmlns:android="http://schemas.android.com/apk/res/android">
<data>
<variable
name="stu"
type="com.example.guoss.databindingdemo.entity.StuBean" />
</data>
<LinearLayout
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_marginLeft="20dp"
android:layout_marginRight="20dp"
android:orientation="vertical">
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@{stu.name}"
android:padding="12dp"
android:textColor="@{@color/text_color_3}"
android:textSize="16sp" />
<TextView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@{stu.addr}"
android:padding="12dp"
android:textColor="@{@color/text_color_6}"
android:textSize="14sp" />
</LinearLayout>
</layout>
那DataBinding怎么和RecycleView.Adapter 中使用呢？ 看一下adapter和ViewHolder中的代码
重点是在 onCreateViewHolder函数中 初始化ViewDataBinding相当于初始化view，将初始化后的ViewDataBinding放置在ViewHolder中方便在 onBindViewHolder 函数中使用 setStu 或 setVariable 绑定数据
@Override
public StuViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
StuItemLayoutBinding itemLayoutBinding = DataBindingUtil.inflate(LayoutInflater.from(parent.getContext()),R.layout.stu_item_layout,parent,false);
StuViewHolder viewHolder = new StuViewHolder(itemLayoutBinding.getRoot());
viewHolder.setBinding(itemLayoutBinding);
return viewHolder;
}
@Override
public void onBindViewHolder(StuViewHolder holder, int position) {
StuBean stuBean = mStuList.get(position);
holder.getBinding().setStu(stuBean);
//holder.getBinding().setVariable(BR.stu,stuBean);
holder.getBinding().executePendingBindings();
}
@Override
public int getItemCount() {
return mStuList == null ?0:mStuList.size();
}
使用了DataBinding后ViewHolder 就不用使用findViewById ，但是需要提供ViewDataBinding对象方便后面绑定数据
class StuViewHolder extends RecyclerView.ViewHolder{
private StuItemLayoutBinding binding;
public StuViewHolder(View itemView) {
super(itemView);
}
public void setBinding(StuItemLayoutBinding stuItemLayoutBinding){
this.binding = stuItemLayoutBinding;
}
public StuItemLayoutBinding getBinding() {
return binding;
}
}
接着可以给RecycleView setAdapter了
dataBinding.stuRecycleView.setLayoutManager(new LinearLayoutManager(this));
dataBinding.stuRecycleView.setAdapter(new StuAdapter(stuList));
再想一下，在这个基础上是不是可以将变量抽取出来 用泛型打造一个通用的Adapter
public class BaseRecycleAdapter<E,T extends ViewDataBinding> extends RecyclerView.Adapter<BaseRecycleAdapter.BaseViewHolder>{
private List<E> mList;
private int itemLayoutId;
private int variableId;
public BaseRecycleAdapter(List<E> mList, int itemLayoutId, int variableId) {
this.mList = mList;
this.itemLayoutId = itemLayoutId;
this.variableId = variableId;
}
@Override
public BaseViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
T itemDataBinding = DataBindingUtil.inflate(LayoutInflater.from(parent.getContext()),itemLayoutId,parent,false);
BaseViewHolder viewHolder = new BaseViewHolder(itemDataBinding.getRoot());
viewHolder.setDataBinding(itemDataBinding);
return viewHolder;
}
@Override
public void onBindViewHolder(BaseViewHolder holder, int position) {
E data = mList.get(position);
holder.getDataBinding().setVariable(variableId,data);
holder.getDataBinding().executePendingBindings();
}
@Override
public int getItemCount() {
return mList == null ? 0 : mList.size();
}
public class BaseViewHolder <T extends ViewDataBinding> extends RecyclerView.ViewHolder{
private T dataBinding;
public BaseViewHolder(View itemView) {
super(itemView);
}
public void setDataBinding(T dataBindding){
this.dataBinding = dataBindding;
}
public T getDataBinding(){
return dataBinding;
}
}
}
这样在使用时就更方便了
dataBinding.stuRecycleView.setLayoutManager(new LinearLayoutManager(this));
dataBinding.stuRecycleView.setAdapter(new BaseRecycleAdapter(stuList,R.layout.stu_item_layout,BR.stu));
