Android 更改recyclerview中所选项目的背景色
如何更改“我的循环视图”示例中仅选定视图的背景色？只需更改单击的itemview的背景色。 一次只能显示一个选定项目，背景颜色必须更改，其余项目需要与选择前相同。 这是我的密码： main活动Android 更改recyclerview中所选项目的背景色,android,background,android-recyclerview,Android,Background,Android Recyclerview,如何更改“我的循环视图”示例中仅选定视图的背景色？只需更改单击的itemview的背景色。 一次只能显示一个选定项目，背景颜色必须更改，其余项目需要与选择前相同。 这是我的密码： main活动 public class MainActivity extends AppCompatActivity { RecyclerView rv1; private final String android_versions[]={ "Donut",
public class MainActivity extends AppCompatActivity {
RecyclerView rv1;
private final String android_versions[]={
"Donut",
"Eclair",
"Froyo",
"Gingerbread",
"Honeycomb",
"Ice Cream Sandwich",
"Jelly Bean",
"KitKat",
"Lollipop",
"Marshmallow"
};
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initViews();
}
private void initViews(){
rv1=(RecyclerView)findViewById(R.id.recyclerView1);
rv1.setHasFixedSize(true);
RecyclerView.LayoutManager layoutManager=new LinearLayoutManager(getApplicationContext());
rv1.setLayoutManager(layoutManager);
RecyclerDataAdapter rda=new RecyclerDataAdapter(rv1,getApplicationContext(),android_versions);
rv1.setAdapter(rda);
}
}
public class RecyclerDataAdapter extends RecyclerView.Adapter<RecyclerDataAdapter.ViewHolder> {
private String android_versionnames[];
private Context context1;
private RecyclerView mRecyclerView;
public RecyclerDataAdapter(RecyclerView recylcerView,Context context,String android_versionnames[]){
this.android_versionnames=android_versionnames;
this.context1=context;
mRecyclerView=recylcerView;
setHasStableIds(true);
System.out.println("Inside dataadapter,Android names : \n ");
for(int i=0;i<android_versionnames.length;i++){
System.out.println("\n"+android_versionnames[i]);
}
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view= LayoutInflater.from(parent.getContext()).inflate(R.layout.row_layout,parent,false);
return new ViewHolder(view);
}
@Override
public void onBindViewHolder(final ViewHolder holder, int position) {
holder.tv1.setText(android_versionnames[position]);
}
@Override
public int getItemCount() {
return android_versionnames.length;
}
public class ViewHolder extends RecyclerView.ViewHolder {
private TextView tv1;
LinearLayout row_linearlayout;
RecyclerView rv2;
public ViewHolder(final View itemView) {
super(itemView);
tv1=(TextView)itemView.findViewById(R.id.txtView1);
row_linearlayout=(LinearLayout)itemView.findViewById(R.id.row_linrLayout);
rv2=(RecyclerView)itemView.findViewById(R.id.recyclerView1);
/*itemView.setBackgroundColor(0x00000000);//to transparent*/
}
}
}
对于（int i=0；i在您的RecyclerView适配器的.onBindViewHolder（）中为项目视图添加单击侦听器。获取当前选定位置并通过.setBackground（）更改颜色，用于先前选定的和当前项目在可绘制文件夹中创建选择器：
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_pressed="true">
<shape>
<solid android:color="@color/blue" />
</shape>
</item>
<item android:state_pressed="false">
<shape>
<solid android:color="@android:color/transparent" />
</shape>
</item>
</selector>
在可绘制文件夹中创建可绘制文件 在RecyclerView onBindViewHolder中
holder.button.setSelected(holder.button.isSelected()?true:false);
最后，我得到了答案
public void onBindViewHolder(final ViewHolder holder, final int position) {
holder.tv1.setText(android_versionnames[position]);
holder.row_linearlayout.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
row_index=position;
notifyDataSetChanged();
}
});
if(row_index==position){
holder.row_linearlayout.setBackgroundColor(Color.parseColor("#567845"));
holder.tv1.setTextColor(Color.parseColor("#ffffff"));
}
else
{
holder.row_linearlayout.setBackgroundColor(Color.parseColor("#ffffff"));
holder.tv1.setTextColor(Color.parseColor("#000000"));
}
}
public class ViewHolder extends RecyclerView.ViewHolder {
private TextView tv1;
LinearLayout row_linearlayout;
RecyclerView rv2;
public ViewHolder(final View itemView) {
super(itemView);
tv1=(TextView)itemView.findViewById(R.id.txtView1);
row_linearlayout=(LinearLayout)itemView.findViewById(R.id.row_linrLayout);
rv2=(RecyclerView)itemView.findViewById(R.id.recyclerView1);
}
}
我可以推荐我在应用程序中使用的此解决方案。我已将onTouchListener的此代码放置在我的ViewHolder类的构造函数中。itemView是构造函数的参数。请确保在此方法上使用return false，因为这需要使用OnClickListener
itemView.setOnTouchListener(new View.OnTouchListener() {
@Override
public boolean onTouch(View v, MotionEvent event) {
if(event.getAction() == MotionEvent.ACTION_DOWN)
{
v.setBackgroundColor(Color.parseColor("#f0f0f0"));
}
if (event.getAction() == MotionEvent.ACTION_UP || event.getAction() == MotionEvent.ACTION_CANCEL)
{
v.setBackgroundColor(Color.TRANSPARENT);
}
return false;
}
});
在我看来，最简单的方法是在adapterPage中添加一个变量作为上次单击的位置 在onBindViewHolder中，粘贴此代码，用于检查上次存储的位置是否与加载位置匹配 常量是我声明全局变量的类
if(Constants.LAST_SELECTED_POSITION_SINGLE_PRODUCT == position) {
//change the view background here
holder.colorVariantThumb.setBackgroundResource(R.drawable.selected_background);
}
//on view click you store the position value and notifyItemRangeChanged will
// call the onBindViewHolder and will check the condition
holder.itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view){
Constants.LAST_SELECTED_POSITION_SINGLE_PRODUCT=position;
notifyItemRangeChanged(0, mColorVariants.size());
}
});
实现这一点的一个非常简单的方法是：
//instance variable
List<View>itemViewList = new ArrayList<>();
//OnCreateViewHolderMethod
@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
final View itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.list_row, parent, false);
final MyViewHolder myViewHolder = new MyViewHolder(itemView);
itemViewList.add(itemView); //to add all the 'list row item' views
//Set on click listener for each item view
itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
for(View tempItemView : itemViewList) {
/** navigate through all the itemViews and change color
of selected view to colorSelected and rest of the views to colorDefault **/
if(itemViewList.get(myViewHolder.getAdapterPosition()) == tempItemView) {
tempItemView.setBackgroundResource(R.color.colorSelected);
}
else{
tempItemView.setBackgroundResource(R.color.colorDefault);
}
}
}
});
return myViewHolder;
}
//instance variable
List<CardView>cardViewList = new ArrayList<>();
public class MyViewHolder extends RecyclerView.ViewHolder {
CardView cardView; //THIS IS MY ROOT VIEW
...
public MyViewHolder(View view) {
super(view);
cardView = view.findViewById(R.id.row_item_card);
...
}
}
@Override
public void onBindViewHolder(final MyViewHolder holder, int position) {
final OurLocationObject locationObject = locationsList.get(position);
...
cardViewList.add(holder.cardView); //add all the cards to this list
holder.cardView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
//All card color is set to colorDefault
for(CardView cardView : cardViewList){
cardView.setCardBackgroundColor(context.getResources().getColor(R.color.colorDefault));
}
//The selected card is set to colorSelected
holder.cardView.setCardBackgroundColor(context.getResources().getColor(R.color.colorSelected));
}
});
}
if (!cardViewList.contains(holder.cardView)) {
cardViewList.add(holder.cardView);
}
我在设置Rv的活动中成功地做到了这一点，而不是通过适配器 如果有人需要做类似的事情，这里的代码 在这种情况下，logClick上的颜色会发生变化
@Override
public void onLongClick(View view, int position) {
Toast.makeText(UltimasConsultasActivity.this, "Item agregado a la lista de mails",
Toast.LENGTH_SHORT).show();
sendMultipleMails.setVisibility(View.VISIBLE);
valueEmail.setVisibility(View.VISIBLE);
itemsSeleccionados.setVisibility(View.VISIBLE);
listaEmails.add(superListItems.get(position));
listaItems ="";
NameOfyourRecyclerInActivity.findViewHolderForAdapterPosition(position).NameOfYourViewInTheViewholder.setBackgroundColor((Color.parseColor("#336F0D")));
for(int itemsSelect = 0; itemsSelect <= listaEmails.size() -1; itemsSelect++){
listaItems += "*"+listaEmails.get(itemsSelect).getDescripcion() + "\n";
}
itemsSeleccionados.setText("Items Seleccionados : "+ "\n" + listaItems);
}
}));
@覆盖
仅长按公共无效（视图，int位置）{
Toast.makeText（UltimasConsultasActivity.this，“邮件列表中的项目agregado a”，
吐司。长度（短）。show（）；
send.setVisibility（View.VISIBLE）；
valueEmail.setVisibility（View.VISIBLE）；
itemseleccionados.setVisibility（View.VISIBLE）；
添加（superListItems.get（position））；
listaItems=“”；
您的回收活动的名称。为AdapterPosition（position）查找查看文件夹。您在ViewHolder.setBackgroundColor中的视图名称（（Color.parseColor（“#336F0D”））；
对于（int itemsSelect=0；itemsSelect我所做的就是使用一个静态变量在RecyclerView中存储项目的上次单击位置，然后通知适配器在上次单击位置更新布局，即notifyItemChanged（lastClickedPosition）无论何时单击一个新位置。在整个布局上调用notifyDataSetChanged（）都是非常昂贵且不可行的，因此仅对一个位置执行此操作要好得多
以下是此操作的代码：
public class RecyclerDataAdapter extends RecyclerView.Adapter<RecyclerDataAdapter.ViewHolder> {
private String android_versionnames[];
private Context mContext;
private static lastClickedPosition = -1; // Variable to store the last clicked item position
public RecyclerDataAdapter(Context context,String android_versionnames[]){
this.android_versionnames = android_versionnames;
this.mContext = context;
}
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(mContext).inflate(R.layout.row_layout,
parent, false);
return new ViewHolder(view);
}
@Override
public void onBindViewHolder(final ViewHolder holder, int position) {
holder.tv1.setText(android_versionnames[position]);
holder.itemView.setBackgroundColor(mContext.getResources().
getColor(R.color.cardview_light_background));
holder.itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
v.setBackgroundColor(mContext.getResources().
getColor(R.color.dark_background));
if (lastClickedPosition != -1)
notifyItemChanged(lastClickedPosition);
lastClickedPosition = position;
}
});
}
@Override
public int getItemCount() {
return android_versionnames.length;
}
public class ViewHolder extends RecyclerView.ViewHolder {
private TextView tv1;
public ViewHolder(final View itemView) {
super(itemView);
tv1=(TextView)itemView.findViewById(R.id.txtView1);
}
}
}
公共类RecyclerDataAdapter扩展了RecyclerView.Adapter{
私有字符串android_versionnames[]；
私有上下文；
私有静态lastClickedPosition=-1；//用于存储上次单击的项目位置的变量
public RecyclerDataAdapter（上下文上下文，字符串android_versionnames[]）{
this.android_versionnames=android_versionnames；
this.mContext=上下文；
}
}
@凌驾
public ViewHolder onCreateViewHolder（视图组父级，int-viewType）{
视图=布局从（mContext）变平。充气（R.layout.row\u布局，
父母，假）；
返回新的ViewHolder（视图）；
}
@凌驾
公共无效onBindViewHolder（最终ViewHolder，内部位置）{
holder.tv1.setText（android_versionnames[position]）；
holder.itemView.setBackgroundColor（mContext.getResources（）。
getColor（R.color.cardview_light_background））；
holder.itemView.setOnClickListener（新视图.OnClickListener（）{
@凌驾
公共void onClick（视图v）{
v、 setBackgroundColor（mContext.getResources（）。
getColor（R.color.dark_背景）；
如果（lastClickedPosition！=-1）
notifyItemChanged（上次单击的位置）；
lastClickedPosition=位置；
}
});
}
@凌驾
public int getItemCount（）{
返回android_versionnames.length；
}
公共类ViewHolder扩展了RecyclerView.ViewHolder{
私有文本视图tv1；
公共视图持有者（最终视图项视图）{
超级（项目视图）；
tv1=（TextView）itemView.findViewById（R.id.txtView1）；
}
}
}
public static class SimpleItemRecyclerViewAdapter
extends RecyclerView.Adapter<SimpleItemRecyclerViewAdapter.ViewHolder> {
private final MainActivity mParentActivity;
private final List<DummyContent.DummyItem> mValues;
private final boolean mTwoPane;
private static int lastClickedPosition=-1;
**private static View viewOld=null;**
private final View.OnClickListener mOnClickListener = new View.OnClickListener() {
@Override
public void onClick(View view) {
DummyContent.DummyItem item = (DummyContent.DummyItem) view.getTag();
if (mTwoPane) {
Bundle arguments = new Bundle();
arguments.putString(ItemDetailFragment.ARG_ITEM_ID, item.id);
ItemDetailFragment fragment = new ItemDetailFragment();
fragment.setArguments(arguments);
mParentActivity.getSupportFragmentManager().beginTransaction()
.replace(R.id.item_detail_container, fragment)
.commit();
} else {
Context context = view.getContext();
Intent intent = new Intent(context, ItemDetailActivity.class);
intent.putExtra(ItemDetailFragment.ARG_ITEM_ID, item.id);
context.startActivity(intent);
}
**view.setBackgroundColor(mParentActivity.getResources().getColor(R.color.SelectedColor));
if(viewOld!=null)
viewOld.setBackgroundColor(mParentActivity.getResources().getColor(R.color.DefaultColor));
viewOld=view;**
}
};
公共静态类SimpleItemRecycleServiceAdapter
扩展RecyclerView.Adapter{
私人最终主要活动；
私人最终清单价值；
私有最终布尔值窗格；
私有静态int lastClickedPosition=-1；
**私有静态视图viewOld=null**
private final View.OnClickListener mOnClickListener=new View.OnClickListener（）{
@凌驾
公共void onClick（视图）{
DummyContent.DummyItem项=（DummyContent.DummyItem）视图.getTag（）；
如果（mTwoPane）{
Bundle arguments=new
if (!cardViewList.contains(holder.cardView)) {
cardViewList.add(holder.cardView);
}
@Override
public void onLongClick(View view, int position) {
Toast.makeText(UltimasConsultasActivity.this, "Item agregado a la lista de mails",
Toast.LENGTH_SHORT).show();
sendMultipleMails.setVisibility(View.VISIBLE);
valueEmail.setVisibility(View.VISIBLE);
itemsSeleccionados.setVisibility(View.VISIBLE);
listaEmails.add(superListItems.get(position));
listaItems ="";
NameOfyourRecyclerInActivity.findViewHolderForAdapterPosition(position).NameOfYourViewInTheViewholder.setBackgroundColor((Color.parseColor("#336F0D")));
for(int itemsSelect = 0; itemsSelect <= listaEmails.size() -1; itemsSelect++){
listaItems += "*"+listaEmails.get(itemsSelect).getDescripcion() + "\n";
}
itemsSeleccionados.setText("Items Seleccionados : "+ "\n" + listaItems);
}
}));
public class RecyclerDataAdapter extends RecyclerView.Adapter<RecyclerDataAdapter.ViewHolder> {
private String android_versionnames[];
private Context mContext;
private static lastClickedPosition = -1; // Variable to store the last clicked item position
public RecyclerDataAdapter(Context context,String android_versionnames[]){
this.android_versionnames = android_versionnames;
this.mContext = context;
}
}
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view = LayoutInflater.from(mContext).inflate(R.layout.row_layout,
parent, false);
return new ViewHolder(view);
}
@Override
public void onBindViewHolder(final ViewHolder holder, int position) {
holder.tv1.setText(android_versionnames[position]);
holder.itemView.setBackgroundColor(mContext.getResources().
getColor(R.color.cardview_light_background));
holder.itemView.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
v.setBackgroundColor(mContext.getResources().
getColor(R.color.dark_background));
if (lastClickedPosition != -1)
notifyItemChanged(lastClickedPosition);
lastClickedPosition = position;
}
});
}
@Override
public int getItemCount() {
return android_versionnames.length;
}
public class ViewHolder extends RecyclerView.ViewHolder {
private TextView tv1;
public ViewHolder(final View itemView) {
super(itemView);
tv1=(TextView)itemView.findViewById(R.id.txtView1);
}
}
}
public static class SimpleItemRecyclerViewAdapter
extends RecyclerView.Adapter<SimpleItemRecyclerViewAdapter.ViewHolder> {
private final MainActivity mParentActivity;
private final List<DummyContent.DummyItem> mValues;
private final boolean mTwoPane;
private static int lastClickedPosition=-1;
**private static View viewOld=null;**
private final View.OnClickListener mOnClickListener = new View.OnClickListener() {
@Override
public void onClick(View view) {
DummyContent.DummyItem item = (DummyContent.DummyItem) view.getTag();
if (mTwoPane) {
Bundle arguments = new Bundle();
arguments.putString(ItemDetailFragment.ARG_ITEM_ID, item.id);
ItemDetailFragment fragment = new ItemDetailFragment();
fragment.setArguments(arguments);
mParentActivity.getSupportFragmentManager().beginTransaction()
.replace(R.id.item_detail_container, fragment)
.commit();
} else {
Context context = view.getContext();
Intent intent = new Intent(context, ItemDetailActivity.class);
intent.putExtra(ItemDetailFragment.ARG_ITEM_ID, item.id);
context.startActivity(intent);
}
**view.setBackgroundColor(mParentActivity.getResources().getColor(R.color.SelectedColor));
if(viewOld!=null)
viewOld.setBackgroundColor(mParentActivity.getResources().getColor(R.color.DefaultColor));
viewOld=view;**
}
};
userV.invalidateRecycler()
holder.card_User.setCardBackgroundColor(Color.parseColor("#3eb1ae").withAlpha(60))
override fun invalidateRecycler() {
if (v1.recyclerCompanies.childCount > 0) {
v1.recyclerCompanies.childrenRecursiveSequence().iterator().forEach { card ->
if (card is CardView) {
card.setCardBackgroundColor(Color.WHITE)
}
}
}
}
public void onClick(View v){
v.findViewById(R.id.textView).setBackgroundColor(R.drawable.selector_row);
}
private int previousPosition = -1;
private SingleViewItemBinding previousView;
@Override
public void onBindViewHolder(@NonNull final ItemViewHolder holder, final int position) {
holder.viewBinding.setItem(itemList.get(position));
holder.viewBinding.rlContainerMain.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
clickRecyclerView.clickRecyclerItem(position, 0);
previousPosition = position;
notifyItemChanged(position);
if(previousView != null){
previousView.rlContainerMain.setBackgroundColor(
ContextCompat.getColor(context, R.color.colorGrayLight));
}
}
});
if(position == previousPosition){
previousView = holder.viewBinding;
holder.viewBinding.rlContainerMain.setBackgroundColor(
ContextCompat.getColor(context, R.color.colorPrimary));
}
else {
holder.viewBinding.rlContainerMain.setBackgroundColor(
ContextCompat.getColor(context, R.color.colorGrayLight));
}
}
holder.itemView.setBackgroundColor(Color.parseColor("#8DFFFFFF"));
@Override
public void onBindViewHolder(@NonNull final MyViewHolder holder, final int position) {
holder.item_1.setText(list_items.get(position).item_1);
holder.item_2.setText(list_items.get(position).item_2);
holder.select_cb.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
if (isChecked){
holder.itemView.setBackgroundColor(Color.parseColor("#8DFFFFFF"));
}else {
holder.itemView.setBackgroundColor(Color.parseColor("#FFFFFF"));
}
}
});
}
companion object {
var last_position = 0
}
holder.item.setOnClickListener{
holder.item.setBackgroundResource(R.drawable.selected_item)
notifyItemChanged(last_position)
last_position=position
}
@Override
public void onBindViewHolder(@NonNull final ViewHolder holder, final int position) {
holder.texttitle.setText(listTitle.get(position));
holder.itemView.setTag(listTitle.get(position));
holder.texttitle.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
index = position;
notifyDataSetChanged();
}
});
if (index == position)
holder.texttitle.setTextColor(mContext.getResources().getColor(R.color.selectedColor));
else
holder.texttitle.setTextColor(mContext.getResources().getColor(R.color.unSelectedColor));
}
var selectedItems = mutableListOf<Int>(-1)
override fun onBindViewHolder(holder: ContactViewHolder, position: Int) {
// holder.setData(ContactViewModel, position) // I'm passing this to the ViewHolder
holder.itemView.setBackgroundColor(Color.WHITE)
holder.itemView.ivIsSelected.visibility = INVISIBLE
selectedItems.forEach {
if (it == position) {
holder.itemView.setBackgroundColor(Color.argb(45, 0, 255, 43))
holder.itemView.ivIsSelected.visibility = VISIBLE
}
}
holder.itemView.setOnClickListener { it ->
it.setBackgroundColor(Color.BLUE)
selectedItems.add(position)
selectedItems.forEach { selectedItem -> // this forEach is required to refresh all the list
notifyItemChanged(selectedItem)
}
}
}
interface ItemClickListener {
fun onItemClickListener(item: Item, position: Int)
}
container.setOnClickListener {
onClickListener.onItemClickListener(item, position)
}
class MainActivity : AppCompatActivity(), ItemAdapter.ItemClickListener {
override fun onItemClickListener(item: Item, position: Int) {
val itemBackground: ColorDrawable =
binding.recycler[position].background as ColorDrawable
if (itemBackground.color == ContextCompat.getColor(this, R.color.white)) {
binding.recycler.children.iterator().forEach { item ->
item.setBackgroundColor(
ContextCompat.getColor(
this,
R.color.white
)
)
}
binding.recycler[position].setBackgroundColor(
ContextCompat.getColor(this, R.color.teal_200)
)
} else {
binding.recycler.children.iterator().forEach { item ->
item.setBackgroundColor(
ContextCompat.getColor(
this,
R.color.white
)
)
}
}
}