refactor(*): 优化EditableImageAdapter

Author: AndroidCoderPeng

app/src/main/java/com/pengxh/kt/lib/fragments/adapter/EditableImageAdapterFragment.kt

@@ -12,10 +12,14 @@ import com.pengxh.kt.lib.databinding.FragmentAdapterEditableImageBinding
 import com.pengxh.kt.lib.utils.GlideLoadEngine
 import com.pengxh.kt.lite.adapter.EditableImageAdapter
 import com.pengxh.kt.lite.base.KotlinBaseFragment
+import com.pengxh.kt.lite.divider.RecyclerViewItemOffsets
+import com.pengxh.kt.lite.extensions.dp2px
+import com.pengxh.kt.lite.extensions.getScreenWidth
 
 class EditableImageAdapterFragment : KotlinBaseFragment<FragmentAdapterEditableImageBinding>() {
 
     private lateinit var editableImageAdapter: EditableImageAdapter
+    private val marginOffset by lazy { 1.dp2px(requireContext()) }
     private val recyclerViewImages = ArrayList<String>()
 
     override fun initViewBinding(
@@ -30,15 +34,19 @@ class EditableImageAdapterFragment : KotlinBaseFragment<FragmentAdapterEditableI
     }
 
     override fun initOnCreate(savedInstanceState: Bundle?) {
-        editableImageAdapter = EditableImageAdapter(requireContext(), 9, 1)
+        editableImageAdapter =
+            EditableImageAdapter(requireContext(), requireContext().getScreenWidth(), 9, 3, 1)
+        binding.recyclerView.addItemDecoration(
+            RecyclerViewItemOffsets(marginOffset, marginOffset, marginOffset, marginOffset)
+        )
+        binding.recyclerView.adapter = editableImageAdapter
     }
 
     override fun observeRequestState() {
 
     }
 
     override fun initEvent() {
-        binding.recyclerView.adapter = editableImageAdapter
         editableImageAdapter.setOnItemClickListener(object :
             EditableImageAdapter.OnItemClickListener {
             override fun onAddImageClick() {

lite/src/main/java/com/pengxh/kt/lite/adapter/EditableImageAdapter.kt

@@ -9,21 +9,23 @@ import android.widget.LinearLayout
 import androidx.recyclerview.widget.RecyclerView
 import com.bumptech.glide.Glide
 import com.pengxh.kt.lite.R
-import com.pengxh.kt.lite.extensions.dp2px
-import com.pengxh.kt.lite.extensions.getScreenWidth
 
 
 /**
  * 数量可编辑图片适配器
  *
- * @param imageCountLimit 最多显示几张图片，每行3张图片
- * @param spacing 上下左右外边距，无需在 [androidx.recyclerview.widget.RecyclerView] 设置边距
+ * @param context 使用适配的上下文
+ * @param viewWidth RecyclerView实际宽度，一般情况下就是屏幕宽度，但是如果有其他控件和它在同一行，需要计算实际宽度，不然无法正确显示RecyclerView item的布局
+ * @param imageCountLimit 最多显示的图片数目
+ * @param spanCount 每行显示的图片数目
  * */
 class EditableImageAdapter(
-    private val context: Context, private val imageCountLimit: Int, private val spacing: Int
+    private val context: Context,
+    private val viewWidth: Int,
+    private val imageCountLimit: Int,
+    private val spanCount: Int
 ) : RecyclerView.Adapter<ViewHolder>() {
 
-    private val screenWidth by lazy { context.getScreenWidth() }
     private var images: MutableList<String> = ArrayList()
 
     fun setupImage(images: MutableList<String>) {
@@ -49,7 +51,10 @@ class EditableImageAdapter(
 
     override fun onBindViewHolder(holder: ViewHolder, position: Int) {
         val imageView = holder.getView<ImageView>(R.id.imageView)
-        configImageParams(imageView, holder.bindingAdapterPosition)
+        val imageSize = viewWidth / spanCount
+        val params = LinearLayout.LayoutParams(imageSize, imageSize)
+        imageView.layoutParams = params
+
         if (position == itemCount - 1 && images.size < imageCountLimit) {
             imageView.setImageResource(R.drawable.ic_add_pic)
             imageView.setOnClickListener { //添加图片
@@ -68,25 +73,6 @@ class EditableImageAdapter(
         }
     }
 
-    private fun configImageParams(imageView: ImageView, position: Int) {
-        val temp = spacing.dp2px(context)
-        val imageSize = (screenWidth - temp * 3) / 3
-
-        val params = LinearLayout.LayoutParams(imageSize, imageSize)
-        when (position) {
-            0 -> params.setMargins(temp, temp, temp shr 1, temp shr 1)
-            1 -> params.setMargins(temp shr 1, temp, temp shr 1, temp shr 1)
-            2 -> params.setMargins(temp shr 1, temp, temp, temp shr 1)
-            3 -> params.setMargins(temp, temp shr 1, temp shr 1, temp shr 1)
-            4 -> params.setMargins(temp shr 1, temp shr 1, temp shr 1, temp shr 1)
-            5 -> params.setMargins(temp shr 1, temp shr 1, temp, temp shr 1)
-            6 -> params.setMargins(temp, temp shr 1, temp shr 1, temp)
-            7 -> params.setMargins(temp shr 1, temp shr 1, temp shr 1, temp)
-            8 -> params.setMargins(temp shr 1, temp shr 1, temp, temp)
-        }
-        imageView.layoutParams = params
-    }
-
     override fun getItemCount(): Int = if (images.size >= imageCountLimit) {
         imageCountLimit
     } else {