Android 如何比较firebase中的数据？

我想读回Firebase中的数据，该数据是用户输入的医疗=糖尿病。如果该用户有糖尿病病史，将显示一些不允许用户购买的内容。谁能教我如何在android studio中编写此条件

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试试这个方法，这对我很有用

 Query chatRoomsQuery = mFirebaseDatabase.orderByChild("medical").equalTo("your value");


                        chatRoomsQuery.addListenerForSingleValueEvent(new ValueEventListener() {
                            @Override
                            public void onDataChange(DataSnapshot dataSnapshot) {
                                if (dataSnapshot.exists()) {
                                    // dataSnapshot is the "issue" node with all children with id 0

                                    search_list=new ArrayList<SearchModel>();
                                    for (DataSnapshot issue : dataSnapshot.getChildren()) {
                                        // do something with the individual "issues"
                                        UserRegisterModel mModel = issue.getValue(UserRegisterModel.class);
                                        if(mModel.getArea().equals(sel_area))

                                    hidepDialog();

                                }
                            }

                            @Override
                            public void onCancelled(DatabaseError databaseError) {

                            }
                        });

                    }

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对该查询使用query query=reference.childUsers.orderByChildid；使用这个？查看我的答案并根据您的要求进行更改。您能帮我检查代码吗？因为当我单击我的提交按钮时，它不起作用。query=myRef.orderByChildmedical.equalToDiabetes；把这个放在submit方法中

 Query chatRoomsQuery = mFirebaseDatabase.orderByChild("medical").equalTo("your value");


                        chatRoomsQuery.addListenerForSingleValueEvent(new ValueEventListener() {
                            @Override
                            public void onDataChange(DataSnapshot dataSnapshot) {
                                if (dataSnapshot.exists()) {
                                    // dataSnapshot is the "issue" node with all children with id 0

                                    search_list=new ArrayList<SearchModel>();
                                    for (DataSnapshot issue : dataSnapshot.getChildren()) {
                                        // do something with the individual "issues"
                                        UserRegisterModel mModel = issue.getValue(UserRegisterModel.class);
                                        if(mModel.getArea().equals(sel_area))

                                    hidepDialog();

                                }
                            }

                            @Override
                            public void onCancelled(DatabaseError databaseError) {

                            }
                        });

                    }