How to do Arithmetic operations (increment) on an int, which was a string initially-CodePudding

I have a flutter's ElevatedButton to show a rewardedAd. It shows a string:'show ad' initially. But after watching an ad, i want to display an int:' 10' inside it. Also, I want to increment 10 every time I click on it (watch an ad).

my code:

    RewardedAd? _rewardedAd;
      int _rewardedScore = 0;
    
      @override
      void initState() {
        // TODO: implement initState
        super.initState();
    
        _createRewardedAd();
      }
    
      void _createRewardedAd() {
        RewardedAd.load(
          adUnitId: 'ca-app-pub-3940256099942544/5224354917',
          request: AdRequest(),
          rewardedAdLoadCallback: RewardedAdLoadCallback(
            onAdLoaded: (RewardedAd ad) {
              print('$ad loaded.');
              // Keep a reference to the ad so you can show it later.
              setState(() => this._rewardedAd = ad);
            },
            onAdFailedToLoad: (LoadAdError error) {
              print('RewardedAd failed to load: $error');
              setState(() {
                _rewardedAd = null;
              });
            },
          ),
        );
      }
    
      void _showRewardedAd() {
        _rewardedAd?.fullScreenContentCallback = FullScreenContentCallback(
          onAdShowedFullScreenContent: (RewardedAd ad) =>
              print('$ad onAdShowedFullScreenContent.'),
          onAdDismissedFullScreenContent: (RewardedAd ad) {
            print('$ad onAdDismissedFullScreenContent.');
            ad.dispose(); // dispose ad and
            _createRewardedAd(); // then, create a new one
          },
          onAdFailedToShowFullScreenContent: (RewardedAd ad, AdError error) {
            print('$ad onAdFailedToShowFullScreenContent: $error');
            ad.dispose(); // dispose ad and
            _createRewardedAd(); // then, create a new one
          },
          onAdImpression: (RewardedAd ad) => print('$ad impression occurred.'),
        );
    
        _rewardedAd?.show(
            onUserEarnedReward: (AdWithoutView ad, RewardItem reward) {
          setState(() {
            _rewardedScore = _rewardedScore   10;
    
          });
        });
    
        _rewardedAd = null;
      }


    Scaffold(
      appBar: AppBar(
        title: Text('Rewarded:  $_rewardedScore'),
        centerTitle: true,
      ),
      body: Center(
        child: ElevatedButton(
          child: Text(
            "show ad",
            style: TextStyle(fontSize: 30),
          ),
          onPressed: () {
            print('clicked rewarded');
            _showRewardedAd();
          },
        ),
      ),
    );

CodePudding user response：

You can either Text(reward.toString()) with int reward

Or (int.parse(reward) 10).toString() with string reward

CodePudding user response：

"I figured it out! Time travel! I figured it out". we go back to time, and bring back the Text() stones, and snap both string and int back back to reality.

make a bool variable.

bool clickedButton = false;

Then, use Ternary Operator to store one of these values:

either the int variable: 10 (if true)
or the string: "Show ad" (if false, as by default)

edit the Text() widget as:

    Text(
                clickedButton? '$_rewardedScore' : 'Show Ad',
                style: TextStyle(fontSize: 30),
              )

CodePudding user response：

Make a nullable String type variable like

String? showAd;

and use it like

Text(showAd ?? "show ad");

For incrementing the value write a function like this

showAd = watchAd(showAd)

String watchAd(String? ad){
    int _newValue = int.parse(ad ?? '0');
    _newValue =10;
    return _newValue.toString();
}