Define the generic render prop for NavigationTransitioner to render scenes.

Summary:
This defines the generic function prop `render(props: NavigationTransitionProps)`
to NavigationTransitioner, which enables developer to render scenes, header, overlay,
underlay...etc.

Differential Revision: D3431478

fbshipit-source-id: 93dbc7da23ad8c95565b01f7865d1e8dfd4401f7

Libraries/NavigationExperimental/NavigationTransitioner.js

@@ -19,15 +19,13 @@ const React = require('React');
 const StyleSheet = require('StyleSheet');
 const View = require('View');
 
-const invariant = require('fbjs/lib/invariant');
-
 import type {
   NavigationAnimatedValue,
   NavigationLayout,
-  NavigationState,
   NavigationScene,
-  NavigationSceneRenderer,
+  NavigationState,
   NavigationTransitionConfigurator,
+  NavigationTransitionProps,
 } from 'NavigationTypeDefinition';
 
 type Props = {
@@ -35,8 +33,7 @@ type Props = {
   navigationState: NavigationState,
   onTransitionEnd: () => void,
   onTransitionStart: () => void,
-  renderOverlay: ?NavigationSceneRenderer,
-  renderScene: NavigationSceneRenderer,
+  render: (props: NavigationTransitionProps) => any,
   style: any,
 };
 
@@ -71,8 +68,7 @@ class NavigationTransitioner extends React.Component<any, Props, State> {
     navigationState: NavigationPropTypes.navigationState.isRequired,
     onTransitionEnd: PropTypes.func,
     onTransitionStart: PropTypes.func,
-    renderOverlay: PropTypes.func,
-    renderScene: PropTypes.func.isRequired,
+    render: PropTypes.func.isRequired,
   };
 
   constructor(props: Props, context: any) {
@@ -162,81 +158,15 @@ class NavigationTransitioner extends React.Component<any, Props, State> {
   }
 
   render(): ReactElement<any> {
-    const overlay = this._renderOverlay();
-    const scenes = this._renderScenes();
     return (
       <View
         onLayout={this._onLayout}
-        style={this.props.style}>
-        <View style={styles.scenes} key="scenes">
-          {scenes}
-        </View>
-        {overlay}
+        style={[styles.main, this.props.style]}>
+        {this.props.render(this._buildTransitionProps())}
       </View>
     );
   }
 
-  _renderScenes(): Array<?ReactElement<any>> {
-    return this.state.scenes.map(this._renderScene, this);
-  }
-
-  _renderScene(scene: NavigationScene): ?ReactElement<any> {
-    const {
-      navigationState,
-      renderScene,
-    } = this.props;
-
-    const {
-      position,
-      progress,
-      scenes,
-    } = this.state;
-
-    return renderScene({
-      layout: this.state.layout,
-      navigationState,
-      position,
-      progress,
-      scene,
-      scenes,
-    });
-  }
-
-  _renderOverlay(): ?ReactElement<any> {
-    if (this.props.renderOverlay) {
-      const {
-        navigationState,
-        renderOverlay,
-      } = this.props;
-
-      const {
-        position,
-        progress,
-        scenes,
-      } = this.state;
-
-      const route = navigationState.routes[navigationState.index];
-
-      const activeScene = scenes.find(scene => {
-        return (!scene.isStale && scene.route === route) ?
-          scene :
-          undefined;
-      });
-
-      invariant(!!activeScene, 'no active scene found');
-
-      return renderOverlay({
-        layout: this.state.layout,
-        navigationState,
-        position,
-        progress,
-        scene: activeScene,
-        scenes,
-      });
-    }
-    return null;
-  }
-
   _onLayout(event: any): void {
     const {height, width} = event.nativeEvent.layout;
 
@@ -260,10 +190,31 @@ class NavigationTransitioner extends React.Component<any, Props, State> {
     }
     this.props.onTransitionEnd && this.props.onTransitionEnd();
   }
+
+  _buildTransitionProps(): NavigationTransitionProps {
+    const {
+      navigationState,
+    } = this.props;
+
+    const {
+      layout,
+      position,
+      progress,
+      scenes,
+    } = this.state;
+
+    return {
+      layout,
+      navigationState,
+      position,
+      progress,
+      scenes,
+    };
+  }
 }
 
 const styles = StyleSheet.create({
-  scenes: {
+  main: {
     flex: 1,
   },
 });

Libraries/NavigationExperimental/NavigationTypeDefinition.js

@@ -45,14 +45,14 @@ export type NavigationScene = {
   route: NavigationRoute,
 };
 
-export type NavigationSceneRendererProps = {
-  // The layout of the containing view of the scenes.
+export type NavigationTransitionProps = {
+  // The layout of the transitioner of the scenes.
   layout: NavigationLayout,
 
-  // The navigation state of the containing view.
+  // The navigation state of the transitioner.
   navigationState: NavigationState,
 
-  // The progressive index of the containing view's navigation state.
+  // The progressive index of the transitioner's navigation state.
   position: NavigationAnimatedValue,
 
   // The value that represents the progress of the transition when navigation
@@ -62,11 +62,19 @@ export type NavigationSceneRendererProps = {
   //  progress.__getAnimatedValue() == 1 : transtion completes.
   progress: NavigationAnimatedValue,
 
+  // All the scenes of the transitioner.
+  scenes: Array<NavigationScene>,
+};
+
+export type NavigationSceneRendererProps = {
+  layout: NavigationLayout,
+  navigationState: NavigationState,
+  position: NavigationAnimatedValue,
+  progress: NavigationAnimatedValue,
+  scenes: Array<NavigationScene>,
+
   // The scene to render.
   scene: NavigationScene,
-
-  // All the scenes of the containing view's.
-  scenes: Array<NavigationScene>,
 };
 
 export type NavigationPanPanHandlers = {