android studio 基图书馆订座 APP 代码实现

这是一个比较大型的项目，需要多个模块的协作完成。以下是基本的步骤和代码实现：

1. 创建一个新项目，并添加以下依赖项到 app 模块的 build.gradle 文件中：

implementation 'com.google.android.material:material:1.2.0'
implementation 'com.squareup.retrofit2:retrofit:2.9.0'
implementation 'com.squareup.retrofit2:converter-gson:2.9.0'
implementation 'com.github.bumptech.glide:glide:4.11.0'
annotationProcessor 'com.github.bumptech.glide:compiler:4.11.0'
implementation 'com.airbnb.android:lottie:3.4.0'

2. 在 res/layout 目录下创建布局文件 activity_main.xml，并添加以下代码：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical">

    <androidx.appcompat.widget.Toolbar
        android:id="@+id/toolbar"
        android:layout_width="match_parent"
        android:layout_height="?attr/actionBarSize"
        android:background="?attr/colorPrimary"
        android:elevation="4dp"
        android:theme="@style/ThemeOverlay.AppCompat.ActionBar" />

    <TextView
        android:id="@+id/text_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:gravity="center"
        android:text="Welcome to the Library Booking App!"
        android:textSize="24sp" />

</LinearLayout>

3. 在 MainActivity 中添加以下代码：

public class MainActivity extends AppCompatActivity {

    private TextView textView;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Toolbar toolbar = findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        textView = findViewById(R.id.text_view);
    }
}

4. 创建一个新的 Java 类 BookApi，并添加以下代码：

public interface BookApi {

    @GET("books")
    Call<List<Book>> getBooks();

    @GET("book/{id}")
    Call<Book> getBook(@Path("id") int id);

    @POST("book")
    Call<Book> createBook(@Body Book book);

    @PUT("book/{id}")
    Call<Book> updateBook(@Path("id") int id, @Body Book book);

    @DELETE("book/{id}")
    Call<Void> deleteBook(@Path("id") int id);

}

5. 创建一个新的 Java 类 Book，并添加以下代码：

public class Book {

    private int id;
    private String title;
    private String author;
    private String coverUrl;

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getAuthor() {
        return author;
    }

    public void setAuthor(String author) {
        this.author = author;
    }

    public String getCoverUrl() {
        return coverUrl;
    }

    public void setCoverUrl(String coverUrl) {
        this.coverUrl = coverUrl;
    }

}

6. 创建一个新的 Java 类 BookAdapter，并添加以下代码：

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

    private List<Book> books;
    private OnItemClickListener onItemClickListener;

    public void setBooks(List<Book> books) {
        this.books = books;
        notifyDataSetChanged();
    }

    public void setOnItemClickListener(OnItemClickListener onItemClickListener) {
        this.onItemClickListener = onItemClickListener;
    }

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

    @Override
    public void onBindViewHolder(@NonNull ViewHolder holder, int position) {
        Book book = books.get(position);
        holder.titleTextView.setText(book.getTitle());
        holder.authorTextView.setText(book.getAuthor());
        Glide.with(holder.coverImageView.getContext())
                .load(book.getCoverUrl())
                .into(holder.coverImageView);
    }

    @Override
    public int getItemCount() {
        return books != null ? books.size() : 0;
    }

    class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {

        ImageView coverImageView;
        TextView titleTextView;
        TextView authorTextView;

        ViewHolder(@NonNull View itemView) {
            super(itemView);
            coverImageView = itemView.findViewById(R.id.cover_image_view);
            titleTextView = itemView.findViewById(R.id.title_text_view);
            authorTextView = itemView.findViewById(R.id.author_text_view);
            itemView.setOnClickListener(this);
        }

        @Override
        public void onClick(View v) {
            if (onItemClickListener != null) {
                onItemClickListener.onItemClick(getAdapterPosition());
            }
        }
    }

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

7. 在 res/layout 目录下创建布局文件 item_book.xml，并添加以下代码：

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:padding="16dp"
    android:orientation="horizontal">

    <ImageView
        android:id="@+id/cover_image_view"
        android:layout_width="96dp"
        android:layout_height="128dp"
        android:scaleType="centerCrop"
        android:src="@drawable/ic_book" />

    <LinearLayout
        android:layout_width="0dp"
        android:layout_height="wrap_content"
        android:layout_marginStart="16dp"
        android:layout_weight="1"
        android:orientation="vertical">

        <TextView
            android:id="@+id/title_text_view"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="Book Title"
            android:textSize="18sp" />

        <TextView
            android:id="@+id/author_text_view"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:text="Author"
            android:textSize="16sp" />

    </LinearLayout>

</LinearLayout>

8. 修改 activity_main.xml 文件中的代码，将 TextView 替换为 RecyclerView，并添加以下代码：

<androidx.recyclerview.widget.RecyclerView
    android:id="@+id/recycler_view"
    android:layout_width="match_parent"
    android:layout_height="match_parent" />

9. 在 MainActivity 中添加以下代码：

public class MainActivity extends AppCompatActivity {

    private BookAdapter bookAdapter;
    private BookApi bookApi;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Toolbar toolbar = findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);

        RecyclerView recyclerView = findViewById(R.id.recycler_view);
        recyclerView.setLayoutManager(new LinearLayoutManager(this));
        bookAdapter = new BookAdapter();
        bookAdapter.setOnItemClickListener(new BookAdapter.OnItemClickListener() {
            @Override
            public void onItemClick(int position) {
                // TODO: Handle item click event
            }
        });
        recyclerView.setAdapter(bookAdapter);

        Retrofit retrofit = new Retrofit.Builder()
                .baseUrl("http://your.api.url/")
                .addConverterFactory(GsonConverterFactory.create())
                .build();
        bookApi = retrofit.create(BookApi.class);

        loadBooks();
    }

    private void loadBooks() {
        Call<List<Book>> call = bookApi.getBooks();
        call.enqueue(new Callback<List<Book>>() {
            @Override
            public void onResponse(Call<List<Book>> call, Response<List<Book>> response) {
                if (response.isSuccessful()) {
                    List<Book> books = response.body();
                    bookAdapter.setBooks(books);
                } else {
                    // TODO: Handle error response
                }
            }

            @Override
            public void onFailure(Call<List<Book>> call, Throwable t) {
                // TODO: Handle network error
            }
        });
    }
}

10. 运行应用程序，如果一切正常，您将看到图书列表。现在，您可以添加其他功能，例如图书详情页面、预订图书等。