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[Jeasmine]

• Add Null safety support

This change is 

[jkasten2]

Reviewed 18 of 18 files at r1.
Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @emawby and @Jeasmine)

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example/lib/main.dart, line 292 at r1 (raw file):

    // Get the value for a trigger by its key
    Object? triggerValue = await OneSignal.shared.getTriggerValueForKey("trigger_3");
    print("'trigger_3' key trigger value: ${triggerValue?.toString() ?? null}");

?? null doesn't seems needed here. Doesn't triggerValue?.toString() result in null if triggerValue is null?

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lib/src/create_notification.dart, line 176 at r1 (raw file):

    if (this.buttons != null) {
      var btns = [];
      this.buttons!.forEach((btn) => btns.add(btn.mapRepresentation()));

Is the ! needed here? Does Dart not infer that it can't be null from the if block it is contained in?

[Jeasmine]

Reviewable status: all files reviewed, 2 unresolved discussions (waiting on @emawby and @jkasten2)

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example/lib/main.dart, line 292 at r1 (raw file):

Previously, jkasten2 (Josh Kasten) wrote…

?? null doesn't seems needed here. Doesn't triggerValue?.toString() result in null if triggerValue is null?

Done.

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lib/src/create_notification.dart, line 176 at r1 (raw file):

Previously, jkasten2 (Josh Kasten) wrote…

Is the ! needed here? Does Dart not infer that it can't be null from the if block it is contained in?

Actually, it doesn't

Error: Method 'forEach' cannot be called on 'List?' because it is potentially null.

• 'List' is from 'dart:core'.
• 'OSActionButton' is from 'package:onesignal_flutter/src/notification.dart' ('../lib/src/notification.dart').
  Try calling using ?. instead.
  this.buttons.forEach((btn) => btns.add(btn.mapRepresentation()));

[jkasten2]

Reviewed 1 of 1 files at r2.
Reviewable status: complete! all files reviewed, all discussions resolved (waiting on @emawby)