Question

我已经创建了一个firebase搜索查询，它运行得很完美。但是现在我似乎无法弄清楚如何进行onlick并获取项目位置。以下是我的火力搜索活动：

mUserDatabase=FirebaseDatabase.getInstance().getReference("Users").child("UserProfile";
        mSearchField = findViewById(R.id.search_field);
        mSearchBtn = findViewById(R.id.search_btn);
        mResultList = findViewById(R.id.result_list);
        mResultList.setHasFixedSize(true);
        mResultList.setLayoutManager(new LinearLayoutManager(this));
        mSearchBtn.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                String searchText = mSearchField.getText().toString();
                firebaseUserSearch(searchText);
            }
        });
    }
    private void firebaseUserSearch(String searchText) {
        Toast.makeText(SearchActivity.this, "Searching......", Toast.LENGTH_LONG).show();

        Query firebaseSearchQuery = mUserDatabase.orderByChild("profession").startAt(searchText).endAt(searchText + "\uf8ff");

        FirebaseRecyclerAdapter<Users, UsersViewHolder> firebaseRecyclerAdapter = new FirebaseRecyclerAdapter<Users, UsersViewHolder>(
                Users.class,
                R.layout.search_list_layout,
                UsersViewHolder.class,
                firebaseSearchQuery
        ) {
            @Override
            protected void populateViewHolder(UsersViewHolder viewHolder, Users model, int position) {

                viewHolder.setDetails(getApplicationContext(), model.getUsername(), model.getSummary(), model.getImageurl());
            }
        };
        mResultList.setAdapter(firebaseRecyclerAdapter);
    }
    public static class UsersViewHolder extends RecyclerView.ViewHolder {
        View mView;
        private TextView user_name;
        private TextView user_summary;
        private ImageView user_image;
        public UsersViewHolder(View itemView) {
            super(itemView);
            mView = itemView;
        }

        public void setDetails(Context ctx, String userName,String userSummary,String userImage){
            user_name = mView.findViewById(R.id.name_text);
             user_summary = mView.findViewById(R.id.summary_text);
            user_image = mView.findViewById(R.id.profile_image);
            user_name.setText(userName);
            user_summary.setText(userSummary);
            Glide.with(ctx).load(userImage).into(user_image);

            itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    int pos = getAdapterPosition();
                    Snackbar.make(v, "Hello,How may i help you", Snackbar.LENGTH_LONG).setAction("Action", null).show();
                }
            });
        }

如果点击搜索结果中的单个项目，我如何在详细信息活动中显示内容。

基于 Parag Pawar的建议，我尝试了以下操作，但它无效＆gt;

       @Override
        protected void populateViewHolder(UsersViewHolder viewHolder, Users model, int position) {

            viewHolder.setDetails(getApplicationContext(), model.getUsername(), model.getSummary(), model.getImageurl());
            final String each_key = getRef(position).getKey();


        }

    };

然后在我的UserViewHolder中初始化了onclick：

  mView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {

                Intent pDetail = new Intent(SearchActivity.this, ProfileDetail.class);
                Users each_key = each_key.get(getAdapterPosition());
                pDetail.putExtra(ProfileDetail.EXTRA_POSITION, each_key.getUserId());
                startActivity(pDetail);


            }
        });

但我收到错误 变量each_key可能尚未初始化

根据 Parag Pawar 的最高建议解决了我的错误，并在populateView`holder中实现了他的onclick，如下所示：

 viewHolder.itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View v) {
                    /*Here use intent.putExtra() to send each_key on other activity and fetch data there*/
                    Toast.makeText(SearchActivity.this, "u clicked......" +position, Toast.LENGTH_LONG).show();
                    Intent each_key = new Intent(SearchActivity.this, ProfileDetail.class);
                    Users user = mResultList.get(position);
                    each_key.putExtra(ProfileDetail.EXTRA_POSITION, user.getUserId());
                    startActivity(each_key);



                } });

但我在这里收到错误：

 Users user = mResultList.get(position);

无法解析方法'get（int）'

mReultList是我的Recyclerview的名称，我按如下方式对其进行了初始化：

private RecyclerView mResultList;

但我不知道我是否正确地这样做了。我知道我应该将结果附加到适配器，但我不知道该怎么做。所以我试过了：

  listItems = new ArrayList<>();
    firebaseRecyclerAdapter = new FirebaseRecyclerAdapter<UsersList>(listItems,this);

但这似乎不起作用

更新代码

我创建了一个数组：

 private List<UsersList> listItems;//UsersList is my modal class

然后将其添加到我的onCreate：

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_search);
    listItems = new ArrayList<>();

然后使用此数组按如下方式实现了putExtra，如下所示：

Intent each_key = new Intent(TestSearch.this, ProfileDetail.class);
                    UsersList user = listItems.get(position);
                  //Here use intent.putExtra() to send each_key on other activity and fetch data there
                    Toast.makeText(TestSearch.this, "u clicked......" +position, Toast.LENGTH_LONG).show();
                    each_key.putExtra(ProfileDetail.EXTRA_POSITION, user.getUserId());
                    startActivity(each_key);

但是当我点击某个项目时出现此错误：

java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
                  at java.util.ArrayList.get(ArrayList.java:411)
                  at com.ecard.ecard.search.TestSearch$2$1.onClick(TestSearch.java:94)
                  at android.view.View.performClick(View.java:5637)
                  at android.view.View$PerformClick.run(View.java:22429)
                  at android.os.Handler.handleCallback(Handler.java:751)
                  at android.os.Handler.dispatchMessage(Handler.java:95)
                  at android.os.Looper.loop(Looper.java:154)
                  at android.app.ActivityThread.main(ActivityThread.java:6119)
                  at java.lang.reflect.Method.invoke(Native Method)
                  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:886)
                  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:776)

Answer 1

要从每个项目中获取密钥，请在populateViewholder中执行示例： -

final String each_key = getRef(position).getKey();

要在每个项目上设置Click Listeners，请在populateViewholder中

viewHolder.itemView.setOnClickListener(new View.OnClickListener() { 
@Override 
public void onClick(View v) { 
            /*Here use intent.putExtra() to send each_key on other activity and fetch data there*/

   } }); }

Answer 2

我说两件事都在populateViewHolder（）中您没有初始化错误，因为您在Viewholder类中使用了each_key。

复制此

    final String each_key = getRef(position).getKey();
viewHolder.itemView.setOnClickListener(new View.OnClickListener() { 
@Override 
public void onClick(View v) { 
/*Here use intent.putExtra() to send each_key on other activity and fetch data there*/ 
} }); }

并将其粘贴到populateViewHolder方法

中

Answer 3

在包含当前活动的活动中要单击的项目：在populateVieHolder中创建一个要引用的String：

 final String single_view = getRef(position).getKey();

然后将onclick附加到ViewHolder：

 viewHolder.itemView.setOnClickListener(new View.OnClickListener() {
                @Override
                public void onClick(View view) {

在您的 OnClick 中，您的意图和 putExtras ：

@Override
public void onClick(View view) {
//give your intent a name to reference from("moreDetail" in this case)
Intent moreDetail = new Intent(SearchActivity.this,MoreDetail.class);
//attach the intent reference to access each item and key 
moreDetail.putExtra(MoreDetail.EXTRA_POSITION,single_view);                       
startActivity(moreDetail);//Start the new activity

然后在您的更多细节活动中：添加ExtraPosition字符串

 String single_view = getIntent().getExtras().getString(MoreDetail.EXTRA_POSITION);//get extra position reference previous view

从此处开始，您需要显示来自firebase的数据

从Firebase访问单个值

    firebaseRef.child(single_view).addListenerForSingleValueEvent(new ValueEventListener() {
               @Override
               public void onDataChange(DataSnapshot dataSnapshot) {
    //For single items
// for example:String user_name = (String) dataSnapshot.child("username").getValue();

或

使用Listview访问附加到适配器的值

firebaseRef.child(single_view).addValueEventListener(new ValueEventListener() { @Override public void onDataChange(DataSnapshot dataSnapshot) { ListItem data = dataSnapshot.getValue(ListItem.class); listItems.add(data); adapter.notifyDataSetChanged(); //if you are accessing your data from a ListView

有很多方法可以做到这一点。另一种方法是在你的Recycler适配器中创建一个interface.declare onclick listener和contex：

OnItemClickListener callback; private Context mContext;

然后为您的视图持有者实现Onclick侦听器

public static class UsersViewHolder extends RecyclerView.ViewHolder implements OnItemClickListener {

使用回调功能添加onclick以访问您的View Holder：

@Override public void onClick(View v) { callback.onItemClick(getAdapterPosition()); }

然后创建一个界面：

public interface OnItemClickListener { void onItemClick(int pos); }

根据您的具体情况：在您的主要活动中：

@Override public void onItemClick(int pos) { Intent pDetail = new Intent(this.getContext(), ProfileDetail.class);//get the context ListItem listItem = listItems.get(pos);//get the position //Then your puEtxra here followed by start activity startActivity(pDetail); }

最后在详细信息视图中调用EXTRA_POSITION，然后调用数据快照。您可以在github上的firebase文档和firebase快速入门示例中找到更多详细信息： GitHub FirebaseDocs

如何使用firebase搜索查询结果项实现OnClick项

3 个答案: