Android RecycerView：notifyDataSetChanged（）IllegalStateException

Question

@Override
public void onBindViewHolder(ViewHolder viewHolder, int position) {

     //checkbox view listener
    viewHolder.getCheckbox().setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {

            //update list items
            notifyDataSetChanged();
        }
    });
}

java.lang.IllegalStateException: Cannot call this method while RecyclerView is computing a layout or scrolling
    at android.support.v7.widget.RecyclerView.assertNotInLayoutOrScroll(RecyclerView.java:1462)
    at android.support.v7.widget.RecyclerView$RecyclerViewDataObserver.onChanged(RecyclerView.java:2982)
    at android.support.v7.widget.RecyclerView$AdapterDataObservable.notifyChanged(RecyclerView.java:7493)
    at android.support.v7.widget.RecyclerView$Adapter.notifyDataSetChanged(RecyclerView.java:4338)
    at com.app.myapp.screens.RecycleAdapter.onRowSelect(RecycleAdapter.java:111)

我还使用了notifyItemChanged()，同样的异常。有什么秘密的更新方式来通知适配器有什么变化？

Answer 1

您应该将方法'set OnCheckedChangeListener()'移动到ViewHolder，它是适配器上的内部类。

onbindviewholder()不是初始化viewholder的方法。此方法是刷新每个回收器项的步骤。当调用NotifyDataSetChanged()时，将调用onbindviewholder()作为每个项的次数。

因此，如果将NotifyDataSetChanged()放入oncheckChanged()并在onbindviewholder()中初始化复选框，则由于循环方法调用，将获得IllegalStateException。

单击复选框->onCheckedChanged()->notifyDataSetChanged()->onBindViewHolder()->设置复选框->OnChecked······

简单地说，您可以通过将一个标志放入适配器来解决这个问题。

试试这个，

private boolean onBind;

public ViewHolder(View itemView) {
    super(itemView);
    mCheckBox = (CheckBox) itemView.findViewById(R.id.checkboxId);
    mCheckBox.setOnCheckChangeListener(this);
}

@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
    if(!onBind) {
        // your process when checkBox changed
        // ...

        notifyDataSetChanged();
    }
}

...

@Override
public void onBindViewHolder(YourAdapter.ViewHolder viewHolder, int position) {
    // process other views 
    // ...

    onBind = true;
    viewHolder.mCheckBox.setChecked(trueOrFalse);
    onBind = false;
}