跳转功能完善，可以返回上个页面

app/src/main/java/com/zjgsu/jianshu/Activity/BookInformationActivity.kt

@@ -29,12 +29,14 @@ class BookInformationActivity : AppCompatActivity() {
     private lateinit var authorName: String
     private lateinit var userId:String
     private lateinit var picurl:String
+    private var sourceActivityClass: Class<*>? = null
     override fun onCreate(savedInstanceState: Bundle?) {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_book_info)
         Bmob.initialize(this, "8f9f1d1ea520b0ce4f84a6fa83a5f754")
         bookName = intent.getStringExtra("Book_name") ?: ""
         userId = getSharedPreferences("userinf", Context.MODE_PRIVATE).getString("user_id", "").toString()
+        sourceActivityClass = intent.getSerializableExtra("Source_Activity") as? Class<*>
         loadPerceptions()
         setupRecyclerView()
         loadBookInfo()
@@ -102,7 +104,7 @@ class BookInformationActivity : AppCompatActivity() {
         queryBookshelf.findObjects(object : FindListener<BookShelf>() {
             override fun done(bookshelfItems: MutableList<BookShelf>?, e: BmobException?) {
                 if (e == null && bookshelfItems != null && bookshelfItems.isNotEmpty()) {
-                    bookinfo_addBook.setImageResource(R.drawable.bookshelf2)
+                    bookinfo_addBook.setImageResource(R.drawable.alreadyin)
                 }
             }
         })
@@ -117,8 +119,15 @@ class BookInformationActivity : AppCompatActivity() {
         }
         //TODO:不一定回到MainActivity::class，后面还要在跳转前保存上一个页面
         bookinfo_return.setOnClickListener {
+            if (sourceActivityClass != null) {
+                // 返回到上一个页面
+                val intent = Intent(this, sourceActivityClass!!)
+                startActivity(intent)
+            } else {
+                // 如果没有来源页面信息,则返回到 MainActivity
                 val intent = Intent(this, MainActivity::class.java)
                 startActivity(intent)
+            }
             finish()
         }
 
@@ -131,10 +140,14 @@ class BookInformationActivity : AppCompatActivity() {
             intent.putExtra("Book_name", bookName)
             startActivity(intent)
         }
+        toBookshelf.setOnClickListener {
+            val intent = Intent(this, BookShelfActivity::class.java)
+            startActivity(intent)
+        }
 
         setCommentClickListeners()
     }
-
+    //TODO:以后可以考虑再次点击这个“已加入的按钮”后，弹出一个对话框：是否将该书移除，然后将该书从书架中移除。而不是弹：该书已在您的书架中
     private fun addBookToBookshelf() {
         val queryBookshelf = BmobQuery<BookShelf>()
         queryBookshelf.addWhereEqualTo("userid", userId)
@@ -149,7 +162,7 @@ class BookInformationActivity : AppCompatActivity() {
                     bookshelfRecord.save(object : SaveListener<String>() {
                         override fun done(objectId: String?, saveException: BmobException?) {
                             if (saveException == null) {
-                                bookinfo_addBook.setImageResource(R.drawable.bookshelf2)
+                                bookinfo_addBook.setImageResource(R.drawable.alreadyin)
                                 Toast.makeText(
                                     this@BookInformationActivity,
                                     "添加成功",
@@ -164,7 +177,7 @@ class BookInformationActivity : AppCompatActivity() {
                         }
                     })
                 } else {
-                    Toast.makeText(this@BookInformationActivity, "书本已在您的书架中！", Toast.LENGTH_SHORT)
+                    Toast.makeText(this@BookInformationActivity, "该书已在您的书架中！", Toast.LENGTH_SHORT)
                         .show()
                 }
             }

app/src/main/java/com/zjgsu/jianshu/Activity/GoodBookActivity.kt

@@ -1,5 +1,6 @@
 package com.zjgsu.jianshu
 
+import android.content.Context
 import android.content.Intent
 import android.os.Bundle
 import android.widget.Toast
@@ -24,7 +25,8 @@ class GoodBookActivity : AppCompatActivity() {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_bookrank)
         Bmob.initialize(this, "8f9f1d1ea520b0ce4f84a6fa83a5f754")//连接bmob
-        adapter= BookRankAdapter(goodbookList,false)
+        val userId = getSharedPreferences("userinf", Context.MODE_PRIVATE).getString("user_id", "").toString() //全局范围内userid，登录的时候存进来
+        adapter= BookRankAdapter(this,goodbookList,false,userId)
         bookrank_recyclerView.layoutManager=
             StaggeredGridLayoutManager(1, StaggeredGridLayoutManager.VERTICAL)
         bookrank_recyclerView.adapter=adapter

app/src/main/java/com/zjgsu/jianshu/Activity/HotBookActivity.kt

@@ -1,4 +1,5 @@
 package com.zjgsu.jianshu
+import android.content.Context
 import android.content.Intent
 import android.os.Bundle
 import android.text.TextUtils
@@ -27,7 +28,8 @@ class HotBookActivity: AppCompatActivity() {
         super.onCreate(savedInstanceState)
         setContentView(R.layout.activity_bookrank)
         Bmob.initialize(this, "8f9f1d1ea520b0ce4f84a6fa83a5f754")//连接bmob
-        adapter= BookRankAdapter(hotbookList,true)
+        val userId = getSharedPreferences("userinf", Context.MODE_PRIVATE).getString("user_id", "").toString()
+        adapter= BookRankAdapter(this,hotbookList,true,userId)
         bookrank_recyclerView.layoutManager=StaggeredGridLayoutManager(1, StaggeredGridLayoutManager.VERTICAL)
         bookrank_recyclerView.adapter=adapter
         bookrank_swipeRefresh.setOnRefreshListener {

app/src/main/java/com/zjgsu/jianshu/Activity/LiteratureActivity.kt

@@ -30,7 +30,7 @@ class LiteratureActivity : AppCompatActivity() {
         Bmob.initialize(this, "8f9f1d1ea520b0ce4f84a6fa83a5f754")
         val titleTextView = findViewById<TextView>(R.id.categoryPage_title)
         titleTextView.text = "文学"
-        adapter = BookAdapter2(bookList)
+        adapter = BookAdapter2(bookList,1)
         categoryPage_recyclerView.layoutManager = StaggeredGridLayoutManager(1, StaggeredGridLayoutManager.VERTICAL)
         categoryPage_recyclerView.adapter = adapter
         categoryPage_swipeRefresh.setOnRefreshListener {

app/src/main/java/com/zjgsu/jianshu/Activity/MainActivity.kt

@@ -1,5 +1,6 @@
 package com.zjgsu.jianshu
 
+import android.content.Context
 import android.content.Intent
 import android.os.Bundle
 import android.text.TextUtils

app/src/main/java/com/zjgsu/jianshu/Activity/ManagementActivity.kt

@@ -29,7 +29,7 @@ class ManagementActivity:AppCompatActivity() {
         Bmob.initialize(this, "8f9f1d1ea520b0ce4f84a6fa83a5f754")
         val titleTextView = findViewById<TextView>(R.id.categoryPage_title)
         titleTextView.text = "管理学"
-        adapter = BookAdapter2(bookList)
+        adapter = BookAdapter2(bookList,2)
         categoryPage_recyclerView.layoutManager = StaggeredGridLayoutManager(1, StaggeredGridLayoutManager.VERTICAL)
         categoryPage_recyclerView.adapter = adapter
         categoryPage_swipeRefresh.setOnRefreshListener {

app/src/main/java/com/zjgsu/jianshu/Activity/PhilosophyActivity.kt

@@ -30,7 +30,7 @@ class PhilosophyActivity:AppCompatActivity() {
         Bmob.initialize(this, "8f9f1d1ea520b0ce4f84a6fa83a5f754")
         val titleTextView = findViewById<TextView>(R.id.categoryPage_title)
         titleTextView.text = "哲学"
-        adapter = BookAdapter2(bookList)
+        adapter = BookAdapter2(bookList,5)
         categoryPage_recyclerView.layoutManager = StaggeredGridLayoutManager(1, StaggeredGridLayoutManager.VERTICAL)
         categoryPage_recyclerView.adapter = adapter
         categoryPage_swipeRefresh.setOnRefreshListener {

app/src/main/java/com/zjgsu/jianshu/Activity/PsychologyActivity.kt

@@ -29,7 +29,7 @@ class PsychologyActivity:AppCompatActivity() {
         Bmob.initialize(this, "8f9f1d1ea520b0ce4f84a6fa83a5f754")
         val titleTextView = findViewById<TextView>(R.id.categoryPage_title)
         titleTextView.text = "心理学"
-        adapter = BookAdapter2(bookList)
+        adapter = BookAdapter2(bookList,3)
         categoryPage_recyclerView.layoutManager = StaggeredGridLayoutManager(1, StaggeredGridLayoutManager.VERTICAL)
         categoryPage_recyclerView.adapter = adapter
         categoryPage_swipeRefresh.setOnRefreshListener {

app/src/main/java/com/zjgsu/jianshu/Activity/ScienceActivity.kt

@@ -30,7 +30,7 @@ class ScienceActivity:AppCompatActivity() {
         Bmob.initialize(this, "8f9f1d1ea520b0ce4f84a6fa83a5f754")
         val titleTextView = findViewById<TextView>(R.id.categoryPage_title)
         titleTextView.text = "科学"
-        adapter = BookAdapter2(bookList)
+        adapter = BookAdapter2(bookList,4)
         categoryPage_recyclerView.layoutManager = StaggeredGridLayoutManager(1, StaggeredGridLayoutManager.VERTICAL)
         categoryPage_recyclerView.adapter = adapter
         categoryPage_swipeRefresh.setOnRefreshListener {

app/src/main/java/com/zjgsu/jianshu/Adapter/BookAdapter.kt

@@ -63,6 +63,7 @@ inner class ViewHolder(view: View) : RecyclerView.ViewHolder(view) {
         holder.outerLinearLayout.setOnClickListener{
             val intent = Intent(holder.itemView.context, BookInformationActivity::class.java)
             intent.putExtra("Book_name", book.name)
+            intent.putExtra("Source_Activity", MainActivity::class.java)
             ContextCompat.startActivity(holder.itemView.context, intent, null)
         }
     }

app/src/main/java/com/zjgsu/jianshu/Adapter/BookAdapter2.kt

@@ -25,7 +25,7 @@ import java.io.InputStream
 import java.net.HttpURLConnection
 import java.net.URL
 
-class BookAdapter2(val bookList: List<Book>) : RecyclerView.Adapter<BookAdapter2.ViewHolder>() {
+class BookAdapter2(val bookList: List<Book>,val categoryId:Int) : RecyclerView.Adapter<BookAdapter2.ViewHolder>() {
 
     inner class ViewHolder(view: View) : RecyclerView.ViewHolder(view) {
         val bookList_Image: ImageView = view.findViewById(R.id.book_Image)

app/src/main/java/com/zjgsu/jianshu/Adapter/BookRankAdapter.kt

@@ -1,19 +1,29 @@
 package com.zjgsu.jianshu.Adapter
 
+import android.content.Context
 import android.content.Intent
 import android.media.Image
+import android.util.Log
 import android.view.LayoutInflater
 import android.view.View
 import android.view.ViewGroup
 import android.widget.ImageView
 import android.widget.LinearLayout
 import android.widget.TextView
+import android.widget.Toast
 import androidx.core.content.ContextCompat
 import androidx.recyclerview.widget.RecyclerView
+import cn.bmob.v3.BmobQuery
+import cn.bmob.v3.exception.BmobException
+import cn.bmob.v3.listener.FindListener
+import cn.bmob.v3.listener.SaveListener
 import com.bumptech.glide.Glide
 import com.zjgsu.jianshu.*
+import com.zjgsu.jianshu.Bmob.BookShelf
+import kotlinx.android.synthetic.main.bookinfo_title.*
 
-class BookRankAdapter(var bookList: List<Book_rank>,val isHotList:Boolean): RecyclerView.Adapter<BookRankAdapter.ViewHolder>() {
+class BookRankAdapter(private val context: Context,var bookList: List<Book_rank>, val isHotList: Boolean, val userId: String) :
+    RecyclerView.Adapter<BookRankAdapter.ViewHolder>() {
     inner class ViewHolder(view: View) : RecyclerView.ViewHolder(view) {
         val bookrank_pic: ImageView = view.findViewById(R.id.bookrank_pic)
         val bookrank_intro: TextView = view.findViewById(R.id.bookrank_intro)
@@ -23,10 +33,13 @@ class BookRankAdapter(var bookList: List<Book_rank>,val isHotList:Boolean): Recy
         val outerLinearLayout: LinearLayout = view.findViewById(R.id.bookrank_outerLinearLayout)
         val bookrank_author: TextView = view.findViewById(R.id.bookrank_author)
         val bookrank_icon: ImageView = view.findViewById(R.id.bookrank_icon)
+        val bookrank_addbook: ImageView = view.findViewById(R.id.bookrank_addbook)
+        val bookrank_add:TextView=view.findViewById(R.id.bookrank_add)
     }
 
     override fun onCreateViewHolder(parent: ViewGroup, viewType: Int): ViewHolder {
-        val view = LayoutInflater.from(parent.context).inflate(R.layout.book_rank2_item, parent, false)
+        val view =
+            LayoutInflater.from(parent.context).inflate(R.layout.book_rank2_item, parent, false)
         return ViewHolder(view)
     }
 
@@ -36,7 +49,8 @@ class BookRankAdapter(var bookList: List<Book_rank>,val isHotList:Boolean): Recy
         holder.bookrank_intro.text = book.intro
         val backgrounds = arrayOf(
             R.drawable.color_lightpurple, R.drawable.color_lightblue,
-            R.drawable.color_lightgreen, R.drawable.color_flesh)
+            R.drawable.color_lightgreen, R.drawable.color_flesh
+        )
         holder.innerLinearLayout.setBackgroundResource(backgrounds[position % backgrounds.size])
         if (isHotList)
             holder.bookrank_desc.text = "在读人数：" + book.courtOfReaders
@@ -69,8 +83,62 @@ class BookRankAdapter(var bookList: List<Book_rank>,val isHotList:Boolean): Recy
         holder.outerLinearLayout.setOnClickListener {
             val intent = Intent(holder.itemView.context, BookInformationActivity::class.java)
             intent.putExtra("Book_name", book.name)
+            if(isHotList)
+                intent.putExtra("Source_Activity", HotBookActivity::class.java)
+            else
+                intent.putExtra("Source_Activity", GoodBookActivity::class.java)
             ContextCompat.startActivity(holder.itemView.context, intent, null)
         }
+        holder.bookrank_addbook.setOnClickListener {
+            val queryBookshelf = BmobQuery<BookShelf>()
+            queryBookshelf.addWhereEqualTo("userid", userId)
+            queryBookshelf.addWhereEqualTo("b_name", book.name)
+            queryBookshelf.findObjects(object : FindListener<BookShelf>() {
+                override fun done(bookshelfItems: MutableList<BookShelf>?, e: BmobException?) {
+                    if (e == null && (bookshelfItems == null || bookshelfItems.isEmpty())) {
+                        val bookshelfRecord = BookShelf()
+                        bookshelfRecord.setb_name(book.name)
+                        bookshelfRecord.setuserid(userId)
+                        bookshelfRecord.setpicurl(book.picUrl)
+                        bookshelfRecord.save(object : SaveListener<String>() {
+                            override fun done(objectId: String?, saveException: BmobException?) {
+                                if (saveException == null) {
+                                    holder.bookrank_addbook.setImageResource(R.drawable.bookshelf2)
+                                    Toast.makeText(
+                                        context,
+                                        "添加成功",
+                                        Toast.LENGTH_SHORT
+                                    ).show()
+                                } else {
+                                    Log.e(
+                                        "BookInfo",
+                                        "Error adding book to bookshelf: ${saveException.message}"
+                                    )
                                 }
+                            }
+                        })
+                    } else {
+                        Toast.makeText(context, "该书已在您的书架中！", Toast.LENGTH_SHORT)
+                            .show()
+                    }
+                }
+            })
+        }
+        fun judgeInBookshelf() {
+            val queryBookshelf = BmobQuery<BookShelf>()
+            queryBookshelf.addWhereEqualTo("userid", userId)
+            queryBookshelf.addWhereEqualTo("b_name", book.name)
+            queryBookshelf.findObjects(object : FindListener<BookShelf>() {
+                override fun done(bookshelfItems: MutableList<BookShelf>?, e: BmobException?) {
+                    if (e == null && bookshelfItems != null && bookshelfItems.isNotEmpty()) {
+                        holder.bookrank_addbook.setImageResource(R.drawable.alreadyin)
+                        holder.bookrank_add.text="已加入"
+                    }
+                }
+            })
+        }
+        judgeInBookshelf()
+    }
+
     override fun getItemCount() = bookList.size
 }

app/src/main/java/com/zjgsu/jianshu/Adapter/BookshelfAdapter.kt

@@ -61,6 +61,7 @@ class BookshelfAdapter(val context: Context, val bookshelf: ArrayList<Book_Shelf
                 } else {
                     val intent = Intent(holder.itemView.context, BookInformationActivity::class.java)
                     intent.putExtra("Book_name", book.bkname)
+                    intent.putExtra("Source_Activity", BookShelfActivity::class.java)
                     ContextCompat.startActivity(holder.itemView.context, intent, null)
                 }
             }

app/src/main/res/layout/book_rank2_item.xml

@@ -8,7 +8,6 @@
     app:cardElevation="4dp">
 
     <LinearLayout
-        android:id="@+id/bookrank_outerLinearLayout"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:orientation="vertical"
@@ -16,6 +15,7 @@
 
         <!-- 第一行：图书封面和简介 -->
         <LinearLayout
+            android:id="@+id/bookrank_outerLinearLayout"
             android:layout_width="match_parent"
             android:layout_height="200dp"
             android:orientation="horizontal">
@@ -117,7 +117,7 @@
                     android:src="@drawable/addbook" />
 
                 <TextView
-                    android:id="@+id/tvLikeText"
+                    android:id="@+id/bookrank_add"
                     android:layout_width="wrap_content"
                     android:layout_height="wrap_content"
                     android:text="加入书架"

app/src/main/res/layout/bookinfo_title.xml

@@ -25,15 +25,15 @@
         android:layout_width="34dp"
         android:layout_height="30dp"
         android:layout_gravity="center"
-        app:srcCompat="@drawable/bookshelf1" />
+        app:srcCompat="@drawable/addbook" />
 
     <ImageView
-        android:id="@+id/imageView2"
+        android:id="@+id/toBookshelf"
-        android:layout_width="37dp"
+        android:layout_width="34dp"
-        android:layout_height="41dp"
+        android:layout_height="30dp"
         android:layout_gravity="center"
         android:layout_margin="5dp"
-        app:srcCompat="@drawable/shopcart" />
+        app:srcCompat="@drawable/bookshelf1" />
 
     <ImageView
         android:id="@+id/imageView7"