feat:调整公聊大厅弹幕数据加载策略（为空才请求）

app/src/main/java/com/chwl/app/home/HomeMessageViewModel.kt

@@ -17,4 +17,10 @@ class HomeMessageViewModel : BaseViewModel() {
             topPublicChatMessageLiveData.postValue(BeanResult.success(value ?: emptyList()))
         }
     }
+
+    fun getTopPublicChatMessageIfNull() {
+        if (topPublicChatMessageLiveData.value?.data.isNullOrEmpty()) {
+            getTopPublicChatMessage()
+        }
+    }
 }

app/src/main/java/com/chwl/app/home/fragment/ContactsListFragment.kt

@@ -188,7 +188,7 @@ class ContactsListFragment : BaseViewBindingFragment<FragmentContactListBinding>
     private fun onVisibleChanged(isVisible: Boolean) {
         switchPublicChatMessageScrollState(isVisible)
         if (isVisible) {
-            viewModel.getTopPublicChatMessage()
+            viewModel.getTopPublicChatMessageIfNull()
         }
     }
 }