diff --git a/lib/QRScanner.js b/lib/QRScanner.js
index 5ac2d86..b075c4f 100644
--- a/lib/QRScanner.js
+++ b/lib/QRScanner.js
@@ -281,31 +281,40 @@ export default class QRScannerView extends Component {
     scanInterval: 2000,
     userFront: false,
   };
-  
+
   constructor(props){
     super(props);
     // 避免频繁触发扫描回调
     this.onScanResult = throttle(this.onScanResult, this.props.scanInterval, { maxWait: 0, trailing: false });
+    // 避免rncamera ready之前调用造成闪退
+    this.cameraReady = false;
   }
   
   componentDidMount(){
-    AppState.addEventListener('change', this.handleAppStateChange);
+    this.appStateChangeListener = AppState.addEventListener('change', this.handleAppStateChange);
   }
   
   componentWillUnmount(){
-    AppState.removeEventListener('change', this.handleAppStateChange);
-    this.rnCamera && this.rnCamera.pausePreview();
+    if (this.appStateChangeListener) {
+      this.appStateChangeListener.remove();
+    }
+    this.rnCamera && this.cameraReady && this.rnCamera.pausePreview();
   }
   
   handleAppStateChange = (currentAppState) => {
     if ( currentAppState !== 'active' ) {
-      this.rnCamera && this.rnCamera.pausePreview();
+      this.rnCamera && this.cameraReady && this.rnCamera.pausePreview();
     } else {
-      this.rnCamera && this.rnCamera.resumePreview();
+      this.rnCamera && this.cameraReady && this.rnCamera.resumePreview();
     }
   };
   
   onScanResult = (e) => this.props.onScanResult(e);
+
+  onCameraReady = () => {
+    this.cameraReady = true;
+    this.handleAppStateChange(AppState.currentState);
+  }
   
   render(){
     const { renderHeaderView, renderFooterView, torchOn, userFront } = this.props;
@@ -313,6 +322,7 @@ export default class QRScannerView extends Component {
     return (
       <RNCamera
         ref={ ref => this.rnCamera = ref }
+        onCameraReady={ this.onCameraReady }
         captureAudio={ false }
         onBarCodeRead={ this.onScanResult }
         type={ userFront ? RNCamera.Constants.Type.front : RNCamera.Constants.Type.back }