动态计算书籍宽度

app/src/main/java/com/novel/read/Ext.kt

@@ -7,3 +7,16 @@ import android.widget.Toast
 fun Context.showToast(msg:String){
     Toast.makeText(this,msg,Toast.LENGTH_SHORT).show()
 }
+
+fun Context.getScreenContentWidth(): Int {
+    val displayMetrics = this.resources.displayMetrics
+    return displayMetrics.widthPixels
+}
+
+fun Context.dp2px(dps: Int): Int {
+    return Math.round(dps.toFloat() * getDensityDpiScale(this))
+}
+
+fun getDensityDpiScale(context: Context): Float {
+    return context.resources.displayMetrics.xdpi / 160.0f
+}

app/src/main/java/com/novel/read/adapter/HumanAdapter.kt

@@ -13,32 +13,35 @@ import androidx.recyclerview.widget.RecyclerView
 import com.novel.read.R
 import com.novel.read.activity.NovelBookDetailActivity
 import com.novel.read.constants.Constant
+import com.novel.read.dp2px
+import com.novel.read.getScreenContentWidth
 import com.novel.read.model.protocol.RecommendListResp
 import com.novel.read.utlis.GlideImageLoader
+import kotlinx.android.synthetic.main.rlv_human_item.view.*
 
 /**
  * create by zlj on 2019/6/19
  * describe:
  */
 class HumanAdapter(private val mList: List<RecommendListResp.ListBean>) : RecyclerView.Adapter<HumanAdapter.ViewHolder>() {
-    private var mContext: Context? = null
+    private lateinit var mContext: Context
 
     override fun onCreateViewHolder(viewGroup: ViewGroup, i: Int): ViewHolder {
-        if (mContext == null) {
         mContext = viewGroup.context
-        }
         val view = LayoutInflater.from(mContext).inflate(R.layout.rlv_human_item, viewGroup, false)
+        val ivSize = (mContext.getScreenContentWidth() - mContext.dp2px(10) * 4) / 3
+        view.cl_layout.layoutParams.width = ivSize
         return ViewHolder(view)
     }
 
     override fun onBindViewHolder(viewHolder: ViewHolder, i: Int) {
         viewHolder.mTvBookName.text = mList[i].book_title
         viewHolder.mTvAuthor.text = mList[i].author
-        GlideImageLoader.displayCornerImage(mContext!!, mList[i].book_cover!!, viewHolder.mIvBook)
+        GlideImageLoader.displayCornerImage(mContext, mList[i].book_cover!!, viewHolder.mIvBook)
-        viewHolder.itemView.setOnClickListener { view ->
+        viewHolder.itemView.setOnClickListener {
             val intent = Intent(mContext, NovelBookDetailActivity::class.java)
             intent.putExtra(Constant.Bundle.BookId, mList[i].book_id)
-            mContext!!.startActivity(intent)
+            mContext.startActivity(intent)
         }
     }
 

app/src/main/java/com/novel/read/adapter/RankAdapter.kt

@@ -13,32 +13,36 @@ import androidx.recyclerview.widget.RecyclerView
 import com.novel.read.R
 import com.novel.read.activity.NovelBookDetailActivity
 import com.novel.read.constants.Constant
+import com.novel.read.dp2px
+import com.novel.read.getScreenContentWidth
 import com.novel.read.model.protocol.RecommendListResp
 import com.novel.read.utlis.GlideImageLoader
+import kotlinx.android.synthetic.main.rlv_human_item.view.*
 
 /**
  * create by zlj on 2019/6/20
  * describe:
  */
-class RankAdapter(private val mList: List<RecommendListResp.ListBean>) : RecyclerView.Adapter<RankAdapter.ViewHolder>() {
+class RankAdapter(private val mList: List<RecommendListResp.ListBean>) :
-    private var mContext: Context? = null
+    RecyclerView.Adapter<RankAdapter.ViewHolder>() {
+    private lateinit var mContext: Context
 
     override fun onCreateViewHolder(viewGroup: ViewGroup, i: Int): ViewHolder {
-        if (mContext == null) {
         mContext = viewGroup.context
-        }
         val view = LayoutInflater.from(mContext).inflate(R.layout.rlv_human_item, viewGroup, false)
+        val ivSize = (mContext.getScreenContentWidth() - mContext.dp2px(10) * 4) / 3
+        view.cl_layout.layoutParams.width = ivSize
         return ViewHolder(view)
     }
 
     override fun onBindViewHolder(viewHolder: ViewHolder, i: Int) {
         viewHolder.mTvBookName.text = mList[i].book_title
         viewHolder.mTvAuthor.text = mList[i].author
-        GlideImageLoader.displayCornerImage(mContext!!, mList[i].book_cover!!, viewHolder.mIvBook)
+        GlideImageLoader.displayCornerImage(mContext, mList[i].book_cover!!, viewHolder.mIvBook)
         viewHolder.itemView.setOnClickListener {
             val intent = Intent(mContext, NovelBookDetailActivity::class.java)
             intent.putExtra(Constant.Bundle.BookId, mList[i].book_id)
-            mContext!!.startActivity(intent)
+            mContext.startActivity(intent)
         }
     }
 

app/src/main/java/com/novel/read/fragment/ManFragment.kt

@@ -10,8 +10,10 @@ import com.novel.read.adapter.HumanAdapter
 import com.novel.read.adapter.RankAdapter
 import com.novel.read.base.NovelBaseFragment
 import com.novel.read.constants.Constant
+import com.novel.read.dp2px
 import com.novel.read.http.AccountManager
 import com.novel.read.model.protocol.RecommendListResp
+import com.novel.read.utlis.EvenItemDecoration
 import kotlinx.android.synthetic.main.fragment_man.*
 import retrofit2.Call
 import retrofit2.Callback
@@ -35,9 +37,12 @@ class ManFragment : NovelBaseFragment() {
     override fun initView() {
         EventManager.instance.registerSubscriber(this)
 
-        rlv_pop.layoutManager = GridLayoutManager(activity, 3)
         mHumanAdapter = HumanAdapter(mHumanList)
-        rlv_pop.adapter = mHumanAdapter
+        rlv_pop.apply {
+            layoutManager = GridLayoutManager(activity, 3)
+            adapter = mHumanAdapter
+            addItemDecoration(EvenItemDecoration(activity!!.dp2px(10), 3))
+        }
 
         val linearLayoutManager = LinearLayoutManager(activity)
         linearLayoutManager.orientation = LinearLayoutManager.HORIZONTAL
@@ -45,9 +50,12 @@ class ManFragment : NovelBaseFragment() {
         mEditAdapter = EditRecommendAdapter(mEditList)
         rlv_recommend.adapter = mEditAdapter
 
-        rlv_update.layoutManager = GridLayoutManager(activity, 3)
         mRankAdapter = RankAdapter(mRankList)
-        rlv_update.adapter = mRankAdapter
+        rlv_update.apply {
+            layoutManager = GridLayoutManager(activity, 3)
+            adapter = mRankAdapter
+            addItemDecoration(EvenItemDecoration(activity!!.dp2px(10), 3))
+        }
     }
 
     override fun initData() {

app/src/main/java/com/novel/read/utlis/EvenItemDecoration.kt

@@ -0,0 +1,22 @@
+package com.novel.read.utlis
+
+import android.graphics.Rect
+import android.view.View
+import androidx.recyclerview.widget.RecyclerView
+
+/**
+ * 设置adapter padding
+ */
+class EvenItemDecoration(private val space: Int, private val column: Int) : RecyclerView.ItemDecoration() {
+    override fun getItemOffsets(outRect: Rect, view: View, parent: RecyclerView, state: RecyclerView.State) {
+        val position = parent.getChildAdapterPosition(view)
+        // 每个span分配的间隔大小
+        val spanSpace = space * (column +1) / column
+        // 列索引
+        val colIndex = position % column
+        // 列左、右间隙
+        outRect.left = space * (colIndex + 1) - spanSpace * colIndex
+        outRect.right = spanSpace * (colIndex + 1) - space * (colIndex + 1)
+        // 行间距
+    }
+}

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

@@ -6,16 +6,18 @@
     android:layout_height="wrap_content"
     android:layout_gravity="center"
     android:layout_marginBottom="10dp"
-    android:layout_marginStart="10dp">
+    android:id="@+id/cl_layout">
 
 
     <androidx.appcompat.widget.AppCompatImageView
         android:id="@+id/iv_book"
-        android:layout_width="100dp"
+        android:layout_width="0dp"
-        android:layout_height="140dp"
+        android:layout_height="0dp"
+        app:layout_constraintDimensionRatio="h,9:13"
         android:scaleType="fitXY"
         android:src="@drawable/cover_default"
         app:layout_constraintLeft_toLeftOf="parent"
+        app:layout_constraintRight_toRightOf="parent"
         app:layout_constraintTop_toTopOf="parent" />
 
     <androidx.appcompat.widget.AppCompatTextView