将数据添加到我的ArrayAdapter中，Iam使用RecyclerView显示这些信息

Question

我的任务是在android演播室制作一个应用程序。这个应用程序将在当地一所大学的一个小部门中显示课程。因此，无论谁使用该应用程序，都可以浏览到20门课程的列表，选择一门课程并获取相关信息。

我已经整理了大部分应用程序，但我很难将这20门课程添加到我的RecyclerView中。我正在尝试使用ArrayAdapter，但我不知道如何将这20门课程添加到其中。我已经成功地添加了要显示的课程，但没有添加到数组中，再加上我这样做的方式是很糟糕的做法(循环20次)，最重要的是，我的搜索栏无法工作，因为数组没有被使用。

，这是我的CourseAdapter.java

package com.example.por16002139.lesson41;

import android.content.Context;
import android.content.Intent;
import android.support.annotation.NonNull;
import android.support.v7.widget.RecyclerView;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
import java.util.ArrayList;
import java.util.List;

public class CourseAdapter extends 
RecyclerView.Adapter<CourseAdapter.ViewHolder> {

private Context mContext;
private List<Course> mCourseDataset = new ArrayList<>();
private List<Course> mCourseDatasetCopy = new ArrayList<>();

//Search bar filter


// Provide a suitable constructor (depends on the kind of dataset passed in)

public CourseAdapter(Context context, List<Course> CourseDataset) {
    mContext = context;
    mCourseDataset = CourseDataset;

}

// Create new views (invoked by the LayoutManager)

@NonNull
public CourseAdapter.ViewHolder onCreateViewHolder(@NonNull ViewGroup 
parent, int viewType) {
    View itemView = 
LayoutInflater.from(parent.getContext()).inflate(R.layout.course_row, 
parent, false);
    return new CourseAdapter.ViewHolder(itemView);
}

// Replace the contents of the View (invoked by the LayoutManager)
@Override
public void onBindViewHolder(@NonNull CourseAdapter.ViewHolder holder, int 
position) {
    // Get element from your dataset at this position
    // Replace the contents of the View with that element
    holder.mCourseImageView.setImageResource(R.drawable.bath_logo);
 holder.mCourseNameTextView.setText
(mCourseDataset.get(position).getCourseName());
holder.mCourseTypeTextView.setText
(mCourseDataset.get(position).getCourseType());
}
// Return the size of your dataset (invoked by the LayoutManager)

@Override
public int getItemCount() {
    return mCourseDataset.size();
}

public void filter(String text) {
    // TODO Filter your EmploymentAdapter here: remember you now have a copy 
of all of the Job's that may be helpful that was assigned in the constructor 
above!
    mCourseDataset.clear();
    if(text.isEmpty()){
        mCourseDataset.addAll(mCourseDatasetCopy);
    } else{
        text = text.toLowerCase();
        for(Course item: mCourseDatasetCopy){
            if(item.getCourseName().toLowerCase().contains(text) || 
item.getCourseType().toLowerCase().contains(text)) {
                mCourseDataset.add(item);
            }
        }
    }
    notifyDataSetChanged();
}


// Provide a reference to the Views for each data item
// Complex data items may need more than one View per item, and
// you provide access to all the Views for a data item in a view holder

public class ViewHolder extends RecyclerView.ViewHolder implements 
View.OnClickListener {

    // each data item is just a string in this case
    public ImageView mCourseImageView;
    public TextView mCourseNameTextView;
    public TextView mCourseTypeTextView;

    public ViewHolder(View view) {
        super(view);
        mCourseImageView = view.findViewById(R.id.course_icon);
        mCourseNameTextView = view.findViewById(R.id.coursename);
        mCourseTypeTextView = view.findViewById(R.id.coursetype);
        view.setOnClickListener(this);


    }

    @Override
    public void onClick(View view) {
        Intent intent = new Intent(mContext, CourseDetailActivity.class);
        intent.putExtra("Course_Name", 
mCourseDataset.get(getAdapterPosition()).getCourseName());
        intent.putExtra("Course_Type", 
mCourseDataset.get(getAdapterPosition()).getCourseType());
        intent.putExtra("Course_description", 
mCourseDataset.get(getAdapterPosition()).getCourseDescription());
        mContext.startActivity(intent);
    }
}

}    }

，这是我的CourseActivity.java

import android.app.SearchManager;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.app.NavUtils;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.ActionBar;
import android.support.v7.app.AppCompatActivity;
import android.support.v7.widget.DividerItemDecoration;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.support.v7.widget.SearchView;
import android.support.v7.widget.Toolbar;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import java.util.ArrayList;
import java.util.List;

public class CourseActivity extends AppCompatActivity {
private RecyclerView mRecyclerView;
private DividerItemDecoration mDividerItemDecoration;
private CourseAdapter mCourseAdapter;
private List<Course> mCourses = new ArrayList<>();

@Override
protected void onCreate(Bundle savedInstanceState) {

    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_course);
    Toolbar toolbar = findViewById(R.id.toolbar);
    toolbar.setTitle(R.string.course_list);

toolbar.setTitleTextColor(ContextCompat.getColor(getApplicationContext(), 
android.R.color.white));
    setSupportActionBar(toolbar);
    ActionBar actionbar = getSupportActionBar();
    if (actionbar != null) {
        actionbar.setDisplayHomeAsUpEnabled(true);

    }

    mRecyclerView = findViewById(R.id.my_recycler_view);

    RecyclerView.LayoutManager mLayoutManager = new 
LinearLayoutManager(this);              // Construct a new layout manager 
for measuring and positioning the RecyclerView
    mRecyclerView.setLayoutManager(mLayoutManager);                                                 
// Set the RecyclerView.LayoutManager that this RecyclerView will use
    mRecyclerView.setHasFixedSize(true);                                                            
// RecyclerView to perform several optimisations in advance, as the 
RecyclerView's size is not affected by the adapter contents

    mRecyclerView.removeItemDecoration(mDividerItemDecoration);                                     
// Remove an RecyclerView.ItemDecoration from this RecyclerView
    mDividerItemDecoration = new DividerItemDecoration(this, 
DividerItemDecoration.VERTICAL);// Create new DividerItemDecoration
    mRecyclerView.addItemDecoration(mDividerItemDecoration);                                        
// Add the DividerItemDecoration to the RecyclerView


    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Access (Database) – Level 1 CLAIT" + i, 
"Part Time Qualification" + i, "Databases are widely used tools in modern 
offices today and this course will enable you to learn substantial skills 
and provide efficient office support. This course is offered at two levels. 
Beginners: you will learn skills varying from table creation, use of 
queries, editing and inputting data into new and existing tables. Advanced: 
you will learn about formula creation within a query, how to produce reports 
and labels and format the design of them once produced." + i);
            mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("AAT (SAGE) Computerised Accounting Award 
Level 2" + i, "Part Time Qualification" + i, "If you already have manual 
bookkeeping knowledge, this course is designed to provide you with the basic 
skills necessary to input and interrogate information held on computerised 
accounting software." + i);
        mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Animation " + i, "Part Time Love2Learn" 
+ i, "This course offers an introductory guide to the animation process from 
storyboard to screen, taught by an industry professional. The focus will be 
on traditional 2D techniques which will also be applicable to 3D computer- 
generated animation. The course is suitable for beginners with an interest 
in illustration who want to apply their skills to animation, as well as 
those who want to know how animation is produced professionally." + i);
        mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Asp.Net " + i, "Part Time Love2Learn" + 
i, "During this course you will learn how to construct complex websites in a 
Microsoft environment using ASP.NET in the C# programming language making 
full use of the MVC (model-view-controller) structure." + i);
        mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Blended Learning, Teaching and 
Assessment Technology " + i, "Part Time Love2Learn" + i, "This course is 
about learning to make the most of  teaching and learning technologies so 
that strategic leaders, teachers and TLAs can enrich the traditional 
learning environment with 21st century teaching, learning and assessment 
tools.  Our experience is that busy staff rarely have the the time to keep 
pace with rapid changes in technology to independently develop necessary 
skills.  Schools could use this course to widen the existing learning 
environment, to develop staff technical knowledge that will complement 
existing pedagogic and curriculum knowledge, and to better prepare learners’ 
fundamental digital skills.  The potential for change includes innovative 
teaching and assessment practices, engaging a wider range of learners and 
increased learner involvement in tracking and assessment.  At the core of 
this course are lessons, skills and practices for Assessment For All and 
mapping Blooms Taxonomy to the digital learning environment." + i);
        mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Computers for Work " + i, "Adult 
Community Learning" + i, "A 13-hour course (unsuitable for beginners) for 
people looking to improve their computer skills for paid employment, 
voluntary/charity work, social enterprise or self-employment. You will be 
supported by a tutor in small friendly group to: nbrush up and develop your 
word processing skills develop the basics of spreadsheets and business 
budgeting design and create PowerPoint slides" + i);
        mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Create Your Own Android App on PC " + i, 
"Part Time Love2Learn" + i, "This Android course will teach you the basics 
on how to create your own Android app on a PC. Students will be supported 
through making their own app that will display pictures from a provided API 
before designing and creating an app of their own." + i);
        mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Digital Art and Design " + i, "Part Time Love2Learn" + i, "Digital technology has become an essential tool for many artists and designers. This course is aimed at supporting artists and designers who wish to incorporate aspects of digital design in their work. Learn about specific programs such as Illustrator and Photoshop (part of Adobe reative Cloud) in our state-of-the-art Mac suites." + i);
        mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Excel (Spreadsheets) – Level 1 CLAIT " + i, "Part Time Qualification" + i, "Excel spreadsheets are a widely used tool in offices and this course will enable you to learn substantial skills and provide efficient office support. You will cover the basics of inserting and formatting text and numbers within a spreadsheet format and the use of basic formula and chart creation. Attendance is flexible and can be arranged with your tutor on application. This course may also be available at our Somer Valley Campus. Please contact the Student Advice Centre or visit www.bathcollege.ac.uk to register your interest." + i);
        mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Get Started with iPads " + i, "Adult Community Learning" + i, "Come and have fun and explore touch screen technology with a course designed especially for beginners. Learn how to: navigate the iPad with the swipe screen technique introduction to Applications – “Apps” explore the camera and video functions use and navigate the web feature to surf the internet become familiar with some of the terminology and jargon related to using an iPad" + i);
        mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Introduction to 3D Games Development in Unity " + i, "Part Time Qualification" + i, "During this course you will learn how to develop a 3D game using the Unity game engine and the C# programming language. The techniques learnt on this course are transferable to all kinds of game development and other types of programming. Throughout this course you will create a simple 3D racing game. Games created using the Unity game engine are compatible with over 10 platforms including Android, iOS, PS4, Xbox One, PC, Mac, Linux and a wide selection of virtual reality headsets." + i);
        mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Introduction to Linux " + i, "Part Time 
Qualification" + i, "Linux powers 94% of the world’s supercomputers, most of 
the servers powering the Internet, the majority of financial trades 
worldwide and a billion Android devices. During this course you will learn 
how to install, maintain and use a Linux system. You will develop a working 
knowledge of Linux using both the graphical interface and command line." + 
i);
        mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Microsoft Excel" + i, "Part Time 
Qualification" + i, "This free 5-hour workshop will be run in a small, 
friendly, tutor-led group and is suitable for anyone looking to improve 
their speadsheet skills – not suitable for beginners. Microsoft Excel is 
widely used in all types of businesses and is excellent for organising and 
sorting data as well as business planning and performing calculations. 
During the workshop you will learn: entering and editing data formatting 
cells and worksheets using basic formulas and functions creating, editing 
and formatting charts sorting and filtering" + i);
        mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Microsoft PowerPoint " + i, "Part Time 
Qualification" + i, "This free 5-hour workshop will be run in a small, 
friendly, tutor led group and is suitable for anyone who would like to 
create a PowerPoint presentation – no prior experience of PowerPoint is 
required but being able to use the mouse and keyboard is essential. This 
workshop will show you how to create a dynamic, informative slideshow using 
text, graphics and animation. During the workshop you will learn how to: 
create a slide presentation format text and backgrounds insert images create 
animations and transitions show a PowerPoint presentation" + i);
        mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Microsoft Word " + i, "Part Time 
Qualification" + i, "Microsoft Word is a popular word processing program 
that allows you to create documents such as letters, brochures, CVs, reports 
etc. This FREE 5-hour workshop will be run in a small, friendly, tutor-led 
group and is suitable for anyone looking to improve their word processing 
skills 
– not suitable for complete beginners. During the workshop you will learn: 
Creating, editing and saving a document Creating folders Formatting text and 
paragraphs Cut/copy/paste How to check spelling Inserting images, tables 
etc." + i);
        mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Stay Safe Online " + i, "Part Time 
Qualification" + i, "Practical advice and support on how to operate safely 
when using internet sites including: looking at parental controls on Windows 
PCs and also android and Apple tablets and smart phones how to decide if an 
email is dangerous how to restrict use within game sites and on social media 
using the internet securely and confidently for the whole family" + i);
        mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Web Development – An introduction to 
HTML " + i, "Part Time Qualification" + i, "This web development course is 
an introduction to HTML focusing on the fundamentals of programming web 
pages. As well as a gentle introduction we will cover linking pages, file 
management, site structure, uploading and downloading web pages, domain 
names, browser compatibility and hosting. This course also introduces you to 
a range of free applications that enable you to edit pages, upload websites 
and create images. This short course is the first stage of a 4-part 
programme of study (HTML, CSS, JavaScript & PHP, and MySQL) that can lead 
you to developing effective interactive websites and/or mobile web 
applications." + i);
        mCourses.add(Course);
    }
    for (int i = 0; i < 1; i++) {
        Course Course = new Course("Web Development – Styling with CSS " + 
i, "Part Time Qualification" + i, "This web development course enables you 
to layout and style your pages using CSS. Learn to style your web content by 
thinking in simple building blocks and understanding the ‘box model’, where 
you can create mobile-responsive layouts using the flexibility of CSS." + 
i);
            mCourses.add(Course);
    }

    // Specify an adapter
    mCourseAdapter = new CourseAdapter(this, mCourses);
    mRecyclerView.setAdapter(mCourseAdapter);

}

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
        // Respond to the action bar's Up/Home button
        case android.R.id.home:
            NavUtils.navigateUpFromSameTask(this);
            return true;
    }
    return super.onOptionsItemSelected(item);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the options menu from XML
      MenuInflater inflater = getMenuInflater();
      inflater.inflate(R.menu.menu, menu);

    // SearchView API Reference: 
https://developer.android.com/reference/android/widget/SearchView
    // Search Overview: https://developer.android.com/guide/topics/search/
    // Search Widget: 
https://developer.android.com/guide/topics/search/search- 
dialog#UsingSearchWidget

    // Get the SearchView and set the searchable configuration
    SearchManager searchManager = (SearchManager) 
getSystemService(Context.SEARCH_SERVICE);
    SearchView searchView = (SearchView) 
menu.findItem(R.id.search_view).getActionView();
    // Assumes current activity is the searchable activity


searchView.setSearchableInfo
(searchManager.getSearchableInfo(getComponentName()));
    searchView.setIconifiedByDefault(true); // Do not iconify the widget; 
expand it by default
    searchView.setQueryHint(getString(R.string.search_hint)); // Set query 
hint
    searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {

        /**
         * Called when the user submits the query
         * @param query The query text that is to be submitted
         * @return False, to let the SearchView perform the default action
         */
        @Override
        public boolean onQueryTextSubmit(String query) {
            // Not really needed in our scenario as we're only concerned 
with the filtering of data
            return false;
        }

        /**
         * Called when the query text is changed by the user
         * @param newText The new content of the query text field
         * @return False, indicating the SearchView should perform the 
default action of showing any suggestions if available
         */
        @Override
        public boolean onQueryTextChange(String newText) {
            mCourseAdapter.filter(newText); // Filter the items based on the 
user search query, searching the title of each traffic event for any partial 
matches
            mRecyclerView.setAdapter(mCourseAdapter); // Set a new adapter 
to provide child views on demand
            mCourseAdapter.notifyDataSetChanged(); // Notify any registered 
observers that the data set has changed
            return false;
        }

    }); // On query text listener to listen to changes in the user search 
query that has been entered
    return true;
}
}

，这是我的Course.java

package com.example.por16002139.lesson41;

public class Course {

private String mCourseName;
private String mCourseType;
private String mCourseDescription;

public Course(String CourseName, String CourseType, String 
CourseDescription){
    this.mCourseName = CourseName;
    this.mCourseType = CourseType;
    this.mCourseDescription = CourseDescription;
}
public String getCourseName() {
    return mCourseName;
}

public String getCourseType() { return mCourseType; }

public String getCourseDescription() {
    return mCourseDescription;
}
}

有什么想法吗？我已经搜索了一天的大部分时间，以至于我在这里向你们寻求帮助，我真的尽力不去做，但是我有点绝望了，谢谢。

Answer 1

在Spinner.上，它表示：可以使用此适配器为AdapterView提供视图，为您提供的数据对象集合中的每个对象返回一个视图，并且可以与基于列表的用户界面小部件(如 ListView 或)一起使用。

它还说:注意:如果考虑在ListView中使用数组适配器，请考虑使用RecyclerView。RecyclerView提供了类似的特性，比ListView提供的性能更好、更灵活。请参阅“回收器视图指南”。

您使用的是RecyclerView.Adapter，它的目标是用于RecyclerView。因此，我们不应该将ArrayAdapter与RecyclerView结合使用。

我认为您可以在ListView中使用ListView而不是RecyclerView，也可以在RecyclerView中继续使用RecyclerView.Adapter。

而且，for循环(int i = 0; i < 1; i++)是多余的，因为这只循环一次(i =o，仅此而已)。所以你只需创建你的20个课程对象，然后mCourses.addAll(Arrays.asList(course1, course2, course3));