fix 聊天闪屏

Author: xhp

android/messagelist/src/main/java/cn/jiguang/imui/messages/ScrollMoreListener.java

@@ -7,6 +7,7 @@
 import android.support.v7.widget.LinearLayoutManager;
 import android.support.v7.widget.RecyclerView;
 import android.support.v7.widget.StaggeredGridLayoutManager;
+import android.util.Log;
 
 public class ScrollMoreListener extends RecyclerView.OnScrollListener {
 
@@ -41,7 +42,7 @@ private int getLastVisibleItem(int[] lastVisibleItemPositions) {
 
     @Override
     public void onScrolled(RecyclerView recyclerView, int dx, int dy) {
-        //setStackFromEnd();
+        setStackFromEnd();
         if (mListener != null) {
             int lastVisibleItemPosition = 0;
             int firstVisibleItemPosition = 0;
@@ -92,26 +93,36 @@ public void handleMessage(Message msg) {
                 } catch (Exception e) {
                     e.printStackTrace();
                 }
-            } else if(msg.what == 2){
+            } else if (msg.what == 2) {
                 try {
                     ll.setStackFromEnd(true);
                 } catch (Exception e) {
                     e.printStackTrace();
                 }
             }
+            lastTime = System.currentTimeMillis();
         }
     };
     LinearLayoutManager ll;
+    long lastTime = 0L;
+
     void setStackFromEnd() {
+        long current = System.currentTimeMillis();
+
+        Log.w("setStackFromEnd", "setStackFromEnd:" + (current - lastTime));
+        if (current - lastTime < 500L) {
+            return;
+        }
+
         if (mLayoutManager instanceof LinearLayoutManager) {
             ll = (LinearLayoutManager) mLayoutManager;
             if (ll.getStackFromEnd()) {
                 if (ll.getChildCount() < mLayoutManager.getItemCount()) {
-                    handler.sendEmptyMessageDelayed(1,150);
+                    handler.sendEmptyMessageDelayed(1, 150);
                 }
             } else {
                 if (ll.getChildCount() >= mLayoutManager.getItemCount()) {
-                    handler.sendEmptyMessageDelayed(2,150);
+                    handler.sendEmptyMessageDelayed(2, 150);
                 }
             }
         }