Activity内のFragmentに, 別Activityからの結果を渡す.
...
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
Fragment fragment = getFragmentManager().findFragmentById(R.id.your_fragment_id);
if (fragment != null) {
fragment.onActivityResult(requestCode, resultCode, data);
}
}
...
fragment いなかったら正しく fragment.setArguments(bundle); で.
こんな記事を見かけた.
Why don't you use enum ? // Speaker Deck
...
public class Status {
public static final int OK = 0;
public static final int ERROR = 1;
}
public void onSomethingAction(int status) {
switch (status) {
case Status.OK:
Log.d(TAG, “Status : OK”);
break;
case Status.ERROR:
Log.d(TAG, “Status : NG”);
break;
}
}
...
より,
...
public enum Status {
OK,
ERROR
}
public void onSomethingAction(Status status) {
Log.d(TAG, “Status : “ + status.name());
}
...
のほうがいいよね, と.
なんとなくここら「enum」についての議論を
よく見かけたような気がしたのですこし調べてみる.
even in the most recent documents android suggests that it's not such a good idea to use enums in an android application. The reason why is because they use up more memory than a static constants variable.
Working with Enums in android - Stack Overflow
Enums often require more than twice as much memory as static constants. You should strictly avoid using enums on Android.
java - Why Android uses Ints instead of Enums - Stack Overflow
Android Memories // Speaker Deck
公式ドキュメントには,
Be aware of memory overhead
…
Enums often require more than twice as much memory as static constants. You should strictly avoid using enums on Android.
…
Managing Your App's Memory | Android Developers
と書いてる.
他に,
Java enums are tremendously more expensive in code size than simple static final ints; classes and objects have not-insignificant overhead, so if you take a very class-heavy approach to your implementation you can end up with a significantly larger code size and RAM footprint for your app.
I really like this article on the importance of thinking about performance…
これに対して Jake Wharton さんも言及.
If you use integer constants instead of enums in your Android app you are a fool. @mttkay's reply here is spot-on: https://t.co/ByedAuLTi1
— Jake Wharton (@JakeWharton) 2015, 1月 4
他には,
Should I strictly avoid using enums on Android?
No. Strictly means they are so bad, they should not be used at all. Possibly a performance issues might arise in an extreme situation like many many many (thousands or millions of) operations with enums (consecutive on the ui thread). Far more common are the network I/O operations that should strictly happen in a background thread. The most common usage of enums is probably some kind of type check - whether an object is this or that which is so fast you won't be able to notice a difference between a single comparison of enums and a comparison of integers.
java - Should I strictly avoid using enums on Android? - Stack Overflow
the original version of that document was just a bunch of prejudices. it's been rewritten to only contain facts backed up by actual benchmarks, and it's updated as the VM is updated. you can find the various benchmarks
結局,
オーバーヘッドは上がるが, まず最初はいうほど気にしなくてもよくね? 最近は. 見通しも良いし. 便利だし.
てな雰囲気でいいのかな. しらんけど.
以下, ヘボ意訳になるけども.
今まで発見されたAndroidのバグの中でも最悪な「Stagefright bug」についてメジャーなAndroidベンダーは修正の対応を始めている.
昨日, Google と同じように Samsung や LG も定期月次OTAセキュリティアップデートの配布を始めた.
LG:(メール)
「LGはすぐにセキュリティアップデートをお客様に提供できる. セキュリティ最優先なことをLGユーザは確認できます.」Samsumg:(ブログ)
「セキュリティ的な脆弱性に対応できていない場合, 素早く更新手続きを実行する.月一の定期更新でそれを行う.」Google:(ブログ)
「Nexusシリーズに更新を8/5(木)に配布を始める.」ほとんどの断片化したAndroidのエコシステムはこれらとは違い, それぞれの携帯メーカーに依存しているが今回の対応は迅速で HTC や SONYのような大手もパッチの配布をすぐに始めている.
みんなの端末にStagefrightの脆弱性があるかどうか確認できるアプリがある.
Big Android Makers Will Now Push Monthly Security Updates | WIRED
こんなとき国内キャリアは関係ないのかなあ, 私のAndroidはどうなるのか...