为什么我的Recycler视图选择了错误的项目以及被点击的精确选择的项目？ Image To Show Recycler View Problem
我想将RecyclerView放置在点击事件启动的弹出活动中，RecycleView应该从视图中更改所选项目的背景。我使用以下Code代码使其弹出
弹出活动代码
DisplayMetrics metrics=new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
float width=metrics.widthPixels*8/10;
float height=metrics.heightPixels*6/10;
getWindow().setLayout((int)width, (int) height);
我的回收站视图适配器的代码如下
public class PopUp extends Activity {
public int counter=0;
private int mItemSelected=-1;
public List<student> students=new ArrayList<student>();
public RecyclerView recyclerView;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//to set content view for that activity
setContentView(R.layout.popup);
//end of the setting the layout for the activity
//this is mechanism to calculate the width and height of the screen
DisplayMetrics metrics=new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
float width=metrics.widthPixels*8/10;
float height=metrics.heightPixels*6/10;
getWindow().setLayout((int)width, (int) height);
//end of the mechanism
//the method to populate the list
populateList();
//end of the method
//now creating the recycler view
recyclerView=(RecyclerView) findViewById(R.id.my_recycler_view);
recyclerView.setHasFixedSize(true);
// use a linear layout manager
LinearLayoutManager mLayoutManager = new
LinearLayoutManager(this,LinearLayoutManager.VERTICAL,false);
recyclerView.setLayoutManager(mLayoutManager);
MyAdapter adapter=new MyAdapter(students);
recyclerView.setAdapter(adapter);
//end of the recycler view
}
//this is event for the ok button
public void Ok(View view){
}
//end of the ok button for the pop activity
//this is event for the button named as cancel
public void Cancel(View view){
}
//end of the cancel button event
//this is method for printing line
public void PrintLine(String line){
Toast.makeText(getApplicationContext(),line,Toast.LENGTH_SHORT).show();
}
//end of the method
//this method to populate the ArrayList
public void populateList(){
String name="Mashhood Qadeer Bhatti";
String address="Sammundri Faisalabad";
boolean status=false;
for(int i=0; i<10; i++){
students.add(new student(name+"\t"+i,address,status));
}
}
//end of the method
//this is section for recycler adapter
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
private List<student> values;
//this is constructor
public MyAdapter(List<student> myDataset) {
values = myDataset;
}
//end of the constructor
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(
parent.getContext());
View v = inflater.inflate(R.layout.row_layout, parent, false);
// set the view's size, margins, paddings and layout parameters
ViewHolder vh = new ViewHolder(v);
return vh;
}
@Override
public void onBindViewHolder(final ViewHolder holder, final int position) {
holder.name.setText(values.get(position).getName().toString());
holder.address.setText(values.get(position).getAddress().toString());
holder.status.setSelected(values.get(position).getSelction());
holder.name.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
if(mItemSelected==position){
v.setBackground(getResources().getDrawable(R.drawable.im));
PrintLine("The position matched"+position);
values.get(position).setSelction(!values.get(position).getSelction());
holder.status.setChecked(values.get(position).getSelction());
}
}
});
}
@Override
public int getItemCount() {
return values.size();
}
//there will be view holder
public class ViewHolder extends RecyclerView.ViewHolder {
// each data item is just a string in this case
public TextView name;
public TextView address;
public View layout;
public RadioButton status;
public ViewHolder(View v) {
super(v);
layout = v;
name = (TextView) v.findViewById(R.id.name);
address = (TextView) v.findViewById(R.id.address);
status=(RadioButton) v.findViewById(R.id.status);
layout.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
notifyDataSetChanged();
mItemSelected=getAdapterPosition();
}
});
/* v.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mItemSelected=getAdapterPosition();
PrintLine("This is position for the"+getAdapterPosition());
notifyDataSetChanged();
values.get(mItemSelected).setSelction(!values.get(mItemSelected).getSelction());
}
});*/
}
}
//end of the view holder
}
//end of that section
}
答案 0 :(得分：3)
回收者视图在OnBindViewHolder.So中回收视图，当点击项目时，它会反映在其他一些位置。解决此问题。
创建一个全局变量来存储点击的位置。
private mItemSelected=-1;
然后在视图内部添加clickListener并onClick存储所单击项目的位置。
public class ViewHolder extends RecyclerView.ViewHolder {
// each data item is just a string in this case
public TextView name;
public TextView address;
public View layout;
public RadioButton status;
public ViewHolder(View v) {
super(v);
layout = v;
name = (TextView) v.findViewById(R.id.name);
address = (TextView) v.findViewById(R.id.address);
status = (RadioButton) v.findViewById(R.id.status);
v.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
mItemSelected = getAdapterPosition();
notifyDataSetChanged();
}
});
}
}
并且在 在OnBindViewHolder中，
@Override
public void onBindViewHolder(final ViewHolder holder, final int position) {
holder.name.setText(values.get(position).getName().toString());
holder.address.setText(values.get(position).getAddress().toString());
holder.status.setSelected(values.get(position).getSelction());
if(mItemSelected==position){
holder.status.setChecked(true);
v.setBackground(getResources().getDrawable(R.drawable.im));
}else{
holder.status.setChecked(false);
v.setBackground(getResources().getDrawable(unselected Item));
}
}
答案 1 :(得分：1)
public class PopUp extends Activity {
public int counter=0;
private int mItemSelected=-1;
public List<student> students=new ArrayList<student>();
public RecyclerView recyclerView;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
//to set content view for that activity
setContentView(R.layout.popup);
//end of the setting the layout for the activity
//this is mechanism to calculate the width and height of the screen
DisplayMetrics metrics=new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(metrics);
float width=metrics.widthPixels*8/10;
float height=metrics.heightPixels*6/10;
getWindow().setLayout((int)width, (int) height);
//end of the mechanism
//the method to populate the list
populateList();
//end of the method
//now creating the recycler view
recyclerView=(RecyclerView) findViewById(R.id.my_recycler_view);
recyclerView.setHasFixedSize(true);
// use a linear layout manager
LinearLayoutManager mLayoutManager = new LinearLayoutManager(this,LinearLayoutManager.VERTICAL,false);
recyclerView.setLayoutManager(mLayoutManager);
MyAdapter adapter=new MyAdapter(students);
recyclerView.setAdapter(adapter);
//end of the recycler view
}
//this is event for the ok button
public void Ok(View view){
}
//end of the ok button for the pop activity
//this is event for the button named as cancel
public void Cancel(View view){
}
//end of the cancel button event
//this is method for printing line
public void PrintLine(String line){
Toast.makeText(getApplicationContext(),line,Toast.LENGTH_SHORT).show();
}
//end of the method
//this method to populate the ArrayList
public void populateList(){
String name="Mashhood Qadeer Bhatti";
String address="Sammundri Faisalabad";
boolean status=false;
for(int i=0; i<10; i++){
students.add(new student(name+"\t"+i,address,status));
}
}
//end of the method
//this is section for recycler adapter
public class MyAdapter extends RecyclerView.Adapter<MyAdapter.ViewHolder> {
private List<student> values;
//this is constructor
public MyAdapter(List<student> myDataset) {
values = myDataset;
}
//end of the constructor
@Override
public ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
LayoutInflater inflater = LayoutInflater.from(
parent.getContext());
View v = inflater.inflate(R.layout.row_layout, parent, false);
// set the view's size, margins, paddings and layout parameters
ViewHolder vh = new ViewHolder(v);
return vh;
}
@Override
public void onBindViewHolder(final ViewHolder holder, final int position) {
holder.name.setText(values.get(position).getName().toString());
holder.address.setText(values.get(position).getAddress().toString());
holder.status.setSelected(values.get(position).getSelction());
if(values.get(position).getSelction()) {
holder.layout.setBackground(getResources().getDrawable(R.drawable.im));
}
else{
holder.layout.setBackground(getResources().getDrawable(R.drawable.imagee));
}
}
@Override
public int getItemCount() {
return values.size();
}
//there will be view holder
public class ViewHolder extends RecyclerView.ViewHolder {
// each data item is just a string in this case
public TextView name;
public TextView address;
public View layout;
public RadioButton status;
public ViewHolder(View v) {
super(v);
layout = v;
name = (TextView) v.findViewById(R.id.name);
address = (TextView) v.findViewById(R.id.address);
status=(RadioButton) v.findViewById(R.id.status);
v.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// mItemSelected = getAdapterPosition();
try{
PrintLine("The adapter position "+getAdapterPosition());
Boolean current_value=values.get(getAdapterPosition()).getSelction();
values.get(getAdapterPosition()).setSelction(!current_value);
notifyDataSetChanged();
}
catch(Exception ex){
PrintLine("Exception of type"+ex.getMessage());
}
}
});
}
}
//end of the view holder
}
//end of that section
}