chore(example): cleanup event listeners

The OSDemo component was registering 10 event listeners but never removing them during clean up. This change updates the example to provide an instance of best practices for anyone using it as a reference.

Author: sherwinski

examples/RNOneSignalTS/OSDemo.tsx

@@ -26,6 +26,72 @@ export interface State {
 }
 
 class OSDemo extends React.Component<Props, State> {
+  // Event listener references for cleanup
+  private onForegroundWillDisplay = (event: any) => {
+    this.OSLog('OneSignal: notification will show in foreground:', event);
+    let notif = event.getNotification();
+
+    const cancelButton = {
+      text: 'Cancel',
+      onPress: () => {
+        event.preventDefault();
+      },
+      style: 'cancel',
+    };
+
+    const completeButton = {
+      text: 'Display',
+      onPress: () => {
+        event.getNotification().display();
+      },
+    };
+
+    Alert.alert(
+      'Display notification?',
+      notif.title,
+      [cancelButton, completeButton],
+      {
+        cancelable: true,
+      },
+    );
+  };
+
+  private onNotificationClick = (event: any) => {
+    this.OSLog('OneSignal: notification clicked:', event);
+  };
+
+  private onIAMClick = (event: any) => {
+    this.OSLog('OneSignal IAM clicked:', event);
+  };
+
+  private onIAMWillDisplay = (event: any) => {
+    this.OSLog('OneSignal: will display IAM: ', event);
+  };
+
+  private onIAMDidDisplay = (event: any) => {
+    this.OSLog('OneSignal: did display IAM: ', event);
+  };
+
+  private onIAMWillDismiss = (event: any) => {
+    this.OSLog('OneSignal: will dismiss IAM: ', event);
+  };
+
+  private onIAMDidDismiss = (event: any) => {
+    this.OSLog('OneSignal: did dismiss IAM: ', event);
+  };
+
+  private onSubscriptionChange = (subscription: any) => {
+    this.OSLog('OneSignal: subscription changed:', subscription);
+  };
+
+  private onPermissionChange = (granted: any) => {
+    this.OSLog('OneSignal: permission changed:', granted);
+  };
+
+  private onUserChange = (event: any) => {
+    this.OSLog('OneSignal: user changed: ', event);
+  };
+
   constructor(props: Props) {
     super(props);
 
@@ -46,70 +112,30 @@ class OSDemo extends React.Component<Props, State> {
     //   enablePushToUpdate: true,
     // });
 
-    OneSignal.Notifications.addEventListener('foregroundWillDisplay', event => {
-      this.OSLog('OneSignal: notification will show in foreground:', event);
-      let notif = event.getNotification();
-
-      const cancelButton = {
-        text: 'Cancel',
-        onPress: () => {
-          event.preventDefault();
-        },
-        style: 'cancel',
-      };
-
-      const completeButton = {
-        text: 'Display',
-        onPress: () => {
-          event.getNotification().display();
-        },
-      };
-
-      Alert.alert(
-        'Display notification?',
-        notif.title,
-        [cancelButton, completeButton],
-        {
-          cancelable: true,
-        },
-      );
-    });
-
-    OneSignal.Notifications.addEventListener('click', event => {
-      this.OSLog('OneSignal: notification clicked:', event);
-    });
-
-    OneSignal.InAppMessages.addEventListener('click', event => {
-      this.OSLog('OneSignal IAM clicked:', event);
-    });
-
-    OneSignal.InAppMessages.addEventListener('willDisplay', event => {
-      this.OSLog('OneSignal: will display IAM: ', event);
-    });
-
-    OneSignal.InAppMessages.addEventListener('didDisplay', event => {
-      this.OSLog('OneSignal: did display IAM: ', event);
-    });
-
-    OneSignal.InAppMessages.addEventListener('willDismiss', event => {
-      this.OSLog('OneSignal: will dismiss IAM: ', event);
-    });
-
-    OneSignal.InAppMessages.addEventListener('didDismiss', event => {
-      this.OSLog('OneSignal: did dismiss IAM: ', event);
-    });
-
-    OneSignal.User.pushSubscription.addEventListener('change', subscription => {
-      this.OSLog('OneSignal: subscription changed:', subscription);
-    });
-
-    OneSignal.Notifications.addEventListener('permissionChange', granted => {
-      this.OSLog('OneSignal: permission changed:', granted);
-    });
-
-    OneSignal.User.addEventListener('change', event => {
-      this.OSLog('OneSignal: user changed: ', event);
-    });
+    OneSignal.Notifications.addEventListener('foregroundWillDisplay', this.onForegroundWillDisplay);
+    OneSignal.Notifications.addEventListener('click', this.onNotificationClick);
+    OneSignal.InAppMessages.addEventListener('click', this.onIAMClick);
+    OneSignal.InAppMessages.addEventListener('willDisplay', this.onIAMWillDisplay);
+    OneSignal.InAppMessages.addEventListener('didDisplay', this.onIAMDidDisplay);
+    OneSignal.InAppMessages.addEventListener('willDismiss', this.onIAMWillDismiss);
+    OneSignal.InAppMessages.addEventListener('didDismiss', this.onIAMDidDismiss);
+    OneSignal.User.pushSubscription.addEventListener('change', this.onSubscriptionChange);
+    OneSignal.Notifications.addEventListener('permissionChange', this.onPermissionChange);
+    OneSignal.User.addEventListener('change', this.onUserChange);
+  }
+
+  componentWillUnmount() {
+    // Clean up all event listeners
+    OneSignal.Notifications.removeEventListener('foregroundWillDisplay', this.onForegroundWillDisplay);
+    OneSignal.Notifications.removeEventListener('click', this.onNotificationClick);
+    OneSignal.InAppMessages.removeEventListener('click', this.onIAMClick);
+    OneSignal.InAppMessages.removeEventListener('willDisplay', this.onIAMWillDisplay);
+    OneSignal.InAppMessages.removeEventListener('didDisplay', this.onIAMDidDisplay);
+    OneSignal.InAppMessages.removeEventListener('willDismiss', this.onIAMWillDismiss);
+    OneSignal.InAppMessages.removeEventListener('didDismiss', this.onIAMDidDismiss);
+    OneSignal.User.pushSubscription.removeEventListener('change', this.onSubscriptionChange);
+    OneSignal.Notifications.removeEventListener('permissionChange', this.onPermissionChange);
+    OneSignal.User.removeEventListener('change', this.onUserChange);
   }
 
   OSLog = (message: string, optionalArg: any = null) => {