代码优化

Author: junixapp

app/src/main/java/com/lxj/androidktxdemo/MainActivity.kt

@@ -31,13 +31,13 @@ data class RestResult(
 
 class MainActivity : BaseActivity() {
     val pages = arrayListOf(
+        PageInfo("RecyclerView相关", RecyclerViewExtDemo()),
             PageInfo("Span相关", SpanExtPage()),
             PageInfo("View相关", ViewExtPage()),
             PageInfo("ImageView相关", ImageViewExtPage()),
             PageInfo("Fragment相关", FragmentExtPage()),
             PageInfo("Http相关", HttpExtFragment()),
             PageInfo("LiveDataBus", LiveDataBusDemo()),
-            PageInfo("RecyclerView相关", RecyclerViewExtDemo()),
             PageInfo("ViewPager2", ViewPager2Demo()),
             PageInfo("播放器", PlayerFragment()),
             PageInfo("Uploader", UploaderFragment()),

app/src/main/java/com/lxj/androidktxdemo/fragment/RecyclerViewExtDemo.kt

@@ -89,8 +89,15 @@ class RecyclerViewExtDemo : BaseFragment() {
         moveBtn.click(50) {
 //            if (data.isEmpty()) return@click
             val random = userVM.listData.value!!.deepCopy<ArrayList<User>>()
+            random.add(User(name = "随机添加-${Random.nextInt(1000)}"))
             random.shuffle()
+
             userVM.replaceList(random)
+//            recyclerView.diffUpdate(UserDiffCallback(old, userVM.listData.value))
+        }
+        clearBtn.click(50) {
+//            if (data.isEmpty()) return@click
+            userVM.clear()
 //            recyclerView.diffUpdate(UserDiffCallback(old, userVM.listData.value))
         }
         val header = TextView(context).apply {

app/src/main/java/com/lxj/androidktxdemo/fragment/UserDiffCallback.kt

@@ -32,7 +32,6 @@ import com.lxj.androidktxdemo.entity.User
 //}
 class UserDiffCallback(oldData: List<User>?, newData: List<User>?) : DiffCallback<User>(oldData, newData) {
    override fun areItemsTheSame(oldItemPosition: Int, newItemPosition: Int): Boolean {
-        if(oldData.isNullOrEmpty() || newData.isNullOrEmpty()) return false
        LogUtils.d("areItemsTheSame ${oldData!![oldItemPosition].id == newData!![newItemPosition].id}")
         return oldData!![oldItemPosition].id == newData!![newItemPosition].id
     }

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

@@ -14,6 +14,7 @@
 
         <ImageView
             android:id="@+id/image"
+            android:background="#aaa"
             android:layout_width="36dp"
             android:layout_height="36dp" />
 
@@ -22,7 +23,7 @@
             android:textSize="16sp"
             android:textColor="#333"
             android:layout_marginLeft="12dp"
-            android:text=""
+            android:text="text"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content" />
     </LinearLayout>

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

@@ -3,43 +3,41 @@
     android:layout_width="match_parent"
     android:orientation="vertical"
     android:layout_height="match_parent">
-    <LinearLayout
-        android:orientation="horizontal"
-        android:layout_width="match_parent"
+    <com.google.android.flexbox.FlexboxLayout xmlns:app="http://schemas.android.com/apk/res-auto"
+        android:layout_width="wrap_content"
+        app:flexWrap="wrap"
         android:layout_height="wrap_content">
-
         <Button
             android:id="@+id/addBtn"
             android:text="增加"
-            android:layout_width="0dp"
-            android:layout_weight="1"
+            android:layout_width="wrap_content"
             android:layout_height="wrap_content" />
         <Button
             android:id="@+id/delBtn"
             android:text="减去"
-            android:layout_width="0dp"
-            android:layout_weight="1"
+            android:layout_width="wrap_content"
             android:layout_height="wrap_content" />
         <Button
             android:id="@+id/updateBtn"
-            android:text="更新字段"
-            android:layout_width="0dp"
-            android:layout_weight="1"
+            android:text="局部更新字段"
+            android:layout_width="wrap_content"
             android:layout_height="wrap_content" />
         <Button
             android:id="@+id/replaceBtn"
-            android:text="替换"
-            android:layout_width="0dp"
-            android:layout_weight="1"
+            android:text="整个替换Item"
+            android:layout_width="wrap_content"
             android:layout_height="wrap_content" />
         <Button
             android:id="@+id/moveBtn"
             android:text="移动"
-            android:layout_width="0dp"
-            android:layout_weight="1"
+            android:layout_width="wrap_content"
             android:layout_height="wrap_content" />
-
-    </LinearLayout>
+        <Button
+            android:id="@+id/clearBtn"
+            android:text="清空"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content" />
+    </com.google.android.flexbox.FlexboxLayout>
     <com.lxj.statelayout.StateLayout
         android:id="@+id/stateRv"
         android:layout_width="match_parent"

library/src/main/java/com/lxj/androidktx/base/ListVM.kt

@@ -112,13 +112,17 @@ abstract class ListVM<T>() : ViewModel(){
     }
 
     fun replaceList(newList: List<T>){
+        val list = listData.value ?: return
         updateOldData()
-        listData.value?.clear()
-        listData.value?.addAll(newList)
-        listData.postValueAndSuccess(listData.value?: CopyOnWriteArrayList())
+        list.clear()
+        if(newList.isNullOrEmpty()){
+            listData.postEmpty(list)
+        }else{
+            list.addAll(newList)
+            listData.postValueAndSuccess(list)
+        }
     }
 
-
     /**
      * 删除数据
      */