【发布时间】:2017-12-13 00:13:56
【问题描述】:
我在CheckBox 上设置了一个onClickListener,用于包含CardViews 列表的RecyclerView。监听器设置在我的ItemHolder 中,扩展了ViewHolder。初次单击CardView 会检查CheckBox 并将CardView 的背景颜色从默认的白色切换为红色。这工作正常。
我还在CardView 本身上设置了一个OnClickListener。 OnClickListener 设置在onCreateViewHolder() 中。单击CardView 会为CardView 启动一个新的详细信息活动。这工作正常。
最后,我尝试在 CardView 本身上设置一个onLongClickListener。 OnLongClickListener 在 onCreateViewHolder() 中设置。长按 CardView 意味着将背景颜色切换为红色并启动 AlertDialog,以便用户可以确认 CardView 将从列表中删除。这可以正常工作,但是当将此代码添加到适配器时,CardView 的 CheckBox 的 OnClickListerner 将不再工作。就好像OnLongClickListner 与 CheckBox 侦听器发生冲突。请注意,我在 itemHolder 的 onLongClick() 代码中“返回 true”。我在这里错过了什么?
Adapter.java
public MyRecylerAdapter(Context context, ArrayList<ListItem> listItems, ArrayList<ListItem> selectedList) {
this.mContext = context;
this.mListItems = listItems;
this.selectedItemsList = selectedList;
}
private int selectedPos = -1;
...
private class ItemHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
private CardView cardView;
private CheckBox chkSelected;
private ItemHolder(final View itemView) {
super(itemView);
cardView = (CardView) itemView.findViewById(R.id.singlecard_view1);
chkSelected = (CheckBox) itemView.findViewById(R.id.chkSelected);
chkSelected.setOnClickListener(this);
}
public void onClick(View v) {
int adapterPos = getAdapterPosition();
if (adapterPos == android.support.v7.widget.RecyclerView.NO_POSITION) return;
if (recyclerItemClickListener !=null) {
recyclerItemClickListener.onCheckBoxClick(v, adapterPos);
}
Integer iPos = adapterPos;
if (((CheckBox)v).isChecked()) {
checkedListItems.add(iPos);
}
else {
checkedListItems.remove(iPos);
}
}
void bind(int position) {
if (checkedListItems.contains(position)) {
chkSelected.setChecked(true);
}
else {
chkSelected.setChecked(false);
}
}
}
@Override
public RecyclerView.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_contact_item, parent, false);
final ItemHolder itemHolder = new ItemHolder(view);
itemHolder.itemView.setOnClickListener(new View.OnClickListener() {
// Handles the row being clicked.
@Override
public void onClick(View view) {
ListItem adapterItem = MyRecylerAdapter.this.getItem(itemHolder.getAdapterPosition());
if (recyclerItemClickListener != null) {
recyclerItemClickListener.onItemClick(itemHolder.itemView, adapterItem);
}
}
});
itemHolder.itemView.setOnLongClickListener(new View.OnLongClickListener() {
@Override
public boolean onLongClick(View view) {
ListItem adapterItem2 = MyRecylerAdapter.this.getItem(itemHolder.getAdapterPosition());
if (recyclerItemClickListener != null) {
recyclerItemClickListener.onItemLongClick(itemHolder.itemView, adapterItem2);
}
int adapterPos2 = itemHolder.getAdapterPosition();
if (adapterPos2 != android.support.v7.widget.RecyclerView.NO_POSITION) {
int lastSelectedPosition = selectedPos;
selectedPos = adapterPos2;
notifyItemChanged(lastSelectedPosition);
notifyItemChanged(selectedPos);
}
return true;
}
});
return itemHolder;
}
public void onBindViewHolder(final RecyclerView.ViewHolder holder, int position) {
final ListItem listItem = mListItems.get(position);
final ItemHolder itemHolder = (ItemHolder) holder;
itemHolder.bind(position);
if (checkedListItems.contains(position)) {
itemHolder.cardView.setActivated(true);
}
else {
itemHolder.cardView.setActivated(false);
}
// **The addition of the below code causes the "itemHolder.cardView.
// setActivated(true);" in onBindViewHolder method to no longer fire, as
// a click on the CheckBox no longer changes the CardView background
// color.**
if (itemHolder.getAdapterPosition() == selectedPos) {
itemHolder.cardView.setActivated(true);
} else {
itemHolder.cardView.setActivated(false);
}
list_contact_item.xml
<?xml version="1.0" encoding="utf-8"?>
<android.support.v7.widget.CardView
xmlns:card_view="http://schemas.android.com/apk/res-auto"
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/singlecard_view1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:foreground="?android:attr/selectableItemBackground"
>
<RelativeLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@drawable/statelist_cardview_background" >
<CheckBox
android:id="@+id/chkSelected"
android:layout_width="wrap_content"
android:layout_height="30dp"
android:layout_alignParentTop="true"
android:layout_alignParentStart="true"
android:layout_alignParentLeft="true"
android:layout_marginLeft="4dp"
android:layout_marginStart="4dp"
android:layout_marginTop="4dp"
android:gravity="center" />
<TextView
android:id="@+id/cardType1"
android:layout_width="wrap_content"
android:layout_height="30dp"
android:layout_toRightOf="@+id/chkSelected"
android:layout_toEndOf="@+id/chkSelected"
android:layout_alignParentTop="true"
android:paddingStart="3dp"
android:paddingLeft="3dp"
android:paddingEnd="6dp"
android:paddingRight="6dp"
android:layout_marginTop="4dp"
android:gravity="center"
android:textColor="#ffffff"
android:textStyle="bold|italic"
style="@style/Base.TextAppearance.AppCompat.Subhead" />
<TextView
android:id="@+id/cardBlankText1"
android:layout_width="wrap_content"
android:layout_height="30dp"
android:layout_alignParentTop="true"
android:layout_toRightOf="@+id/cardType1"
android:layout_toEndOf="@+id/cardType1"
android:layout_toLeftOf="@+id/cardBlankTextNumstotal"
android:layout_toStartOf="@+id/cardBlankTextNumstotal"
android:layout_marginTop="4dp"
android:gravity="center_vertical|end"
android:text="#"
android:textColor="@color/colorFlLabelFinal"
android:textStyle="bold"
android:maxLines="1"
style="@style/Base.TextAppearance.AppCompat.Subhead" />
<TextView
android:id="@+id/cardBlankTextNumstotal"
android:layout_width="wrap_content"
android:layout_height="30dp"
android:layout_alignParentTop="true"
android:layout_alignParentEnd="true"
android:layout_alignParentRight="true"
android:gravity="center"
android:text="actual card #"
android:layout_marginTop="4dp"
android:layout_marginRight="4dp"
android:layout_marginEnd="4dp"
android:freezesText="true"
android:textColor="@android:color/black"
android:maxLines="1"
style="@style/Base.TextAppearance.AppCompat.Subhead" />
<TextView
android:id="@+id/cardBlankText2"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignParentLeft="true"
android:layout_alignParentStart="true"
android:layout_below="@+id/chkSelected"
android:layout_marginTop="4dp"
android:layout_marginLeft="6dp"
android:layout_marginStart="6dp"
android:text="todo"
android:textColor="@android:color/black"
android:textStyle="bold"
android:background="@drawable/todo_underline"
android:maxLines="1"
style="@style/Base.TextAppearance.AppCompat.Headline" />
...
</RelativeLayout>
</android.support.v7.widget.CardView>
statelist_cardview_background.xml
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_activated="true"
android:drawable="@color/item_selected" />
<item android:state_activated="false"
android:drawable="@color/list_contact_item_default" />
</selector>
colors.xml
<?xml version="1.0" encoding="utf-8"?>
<resources>
<color name="list_contact_item_default">#FFFFFF</color>
<color name="item_selected">#FF0000</color>
</resources>
【问题讨论】:
-
使用
chkSelected.setOnCheckedChangeListener()代替chkSelected.setOnClickListener(this)并在onCreateViewHolder()中执行此操作 -
通过阅读许多以前的帖子,不少人提到将 onCheckedChangeListener() 方法与 RecyclerView 适配器一起使用存在问题。
-
你可以通过
holder.vChecked.setOnCheckedChangeListener(null);管理这个然后调用bind()然后分配holder.vChecked.setOnCheckedChangeListener(new OnCheckedChangeListener() ....);` -
好的,我们的想法是通过对 CheckBox 点击事件使用 onCheckedChangeListener 而不是使用第二个 onClickListener 来减少点击冲突的可能性?
-
是的,如果您仍想使用,请尝试在
onCreateViewHolder()或ItemHolder的单个位置进行管理
标签: android checkbox android-recyclerview