修复闪一下问题

android/src/main/java/com/idlefish/flutterboost/XFlutterView.java

@@ -98,6 +98,8 @@ public class XFlutterView extends FrameLayout {
   @Nullable
   private AccessibilityBridge accessibilityBridge;
 
+  private  boolean hasAddFirstFrameRenderedListener=false;
+
   // Directly implemented View behavior that communicates with Flutter.
   private final FlutterRenderer.ViewportMetrics viewportMetrics = new FlutterRenderer.ViewportMetrics();
 
@@ -566,6 +568,7 @@ public class XFlutterView extends FrameLayout {
    * See {@link #detachFromFlutterEngine()} for information on how to detach from a
    * {@link FlutterEngine}.
    */
+
   public void attachToFlutterEngine(
           @NonNull FlutterEngine flutterEngine
   ) {
@@ -588,8 +591,11 @@ public class XFlutterView extends FrameLayout {
     // Instruct our FlutterRenderer that we are now its designated RenderSurface.
     FlutterRenderer flutterRenderer = this.flutterEngine.getRenderer();
     didRenderFirstFrame = flutterRenderer.hasRenderedFirstFrame();
+    if(!hasAddFirstFrameRenderedListener){
+      flutterRenderer.addOnFirstFrameRenderedListener(onFirstFrameRenderedListener);
+      hasAddFirstFrameRenderedListener=true;
+    }
     flutterRenderer.attachToRenderSurface(renderSurface);
-    flutterRenderer.addOnFirstFrameRenderedListener(onFirstFrameRenderedListener);
 
     // Initialize various components that know how to process Android View I/O
     // in a way that Flutter understands.
@@ -643,9 +649,9 @@ public class XFlutterView extends FrameLayout {
     // If the first frame has already been rendered, notify all first frame listeners.
     // Do this after all other initialization so that listeners don't inadvertently interact
     // with a FlutterView that is only partially attached to a FlutterEngine.
-    if (didRenderFirstFrame) {
-      onFirstFrameRenderedListener.onFirstFrameRendered();
-    }
+//    if (didRenderFirstFrame) {
+//      onFirstFrameRenderedListener.onFirstFrameRendered();
+//    }
   }
 
   /**

android/src/main/java/com/idlefish/flutterboost/containers/FlutterSplashView.java

@@ -54,14 +54,13 @@ public class FlutterSplashView extends FrameLayout {
         public void onFlutterEngineDetachedFromFlutterView() {
         }
     };
-
+    int i=0;
     @NonNull
     private final OnFirstFrameRenderedListener onFirstFrameRenderedListener = new OnFirstFrameRenderedListener() {
         @Override
         public void onFirstFrameRendered() {
-            if (splashScreen != null&&!hasRendered) {
+            if (splashScreen != null) {
                 transitionToFlutter();
-                hasRendered=true;
             }
         }
     };
@@ -72,6 +71,7 @@ public class FlutterSplashView extends FrameLayout {
         public void run() {
             removeView(splashScreenView);
             previousCompletedSplashIsolate = transitioningIsolateId;
+            int i=0;
         }
     };