android - 双击 onBack 的 Rxjava 以完成 Activity

Question

我想实现一种 rxjava 的 onback 双击方式

所以，我指的是this answer因为它看起来合理但不起作用它显示 toast 并退出

我观察双背的代码实现是:

private static final long EXIT_TIMEOUT = 2000;
private CompositeDisposable compositeDisposable = new CompositeDisposable();
private PublishSubject<Boolean> backButtonClickSource = PublishSubject.create();

@NonNull
private Disposable observeBackButton() {
    return backButtonClickSource
            .debounce(100, TimeUnit.MILLISECONDS)
            .observeOn(AndroidSchedulers.mainThread())
            .doOnNext(__ -> ToastUtils.showShort(R.string.back_more_toast_message))
            .timeInterval(TimeUnit.MILLISECONDS)
            .skip(1)
            .filter(interval -> interval.time() < EXIT_TIMEOUT)
            .subscribe(__ -> model.finishActivity());

}

对于onBackPressed:

   public void onBackPressed() {
    backButtonClickSource.onNext(true);
}

Answer 1

OP 的问题是他的 onBackPressed() 方法是这样的:

@Override
public void onBackPressed() {
   super.onBackPressed();
   backButtonClickSource.onNext(true);
}

因此，诀窍是删除 super.onBackPressed() 以便您可以根据需要调整该操作。

我已经创建了一个示例，它对我有用，我刚刚删除了你的模型内容和你的 Toast 方法，这是它的样子:

public class MainActivity extends AppCompatActivity {

    private static final long EXIT_TIMEOUT = 2000;
    private PublishSubject<Boolean> backButtonClickSource = PublishSubject.create();


    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        observeBackButton();
    }

    @NonNull
    private Disposable observeBackButton() {
        return backButtonClickSource
                .debounce(100, TimeUnit.MILLISECONDS)
                .observeOn(AndroidSchedulers.mainThread())
                .doOnNext(__ -> Toast.makeText(this, "Press once again to exit", Toast.LENGTH_SHORT).show())
                .timeInterval(TimeUnit.MILLISECONDS)
                .skip(1)
                .filter(interval -> interval.time() < EXIT_TIMEOUT)
                .subscribe(__ -> MainActivity.this.finish());
    }

    @Override
    public void onBackPressed() {
        backButtonClickSource.onNext(true);
    }
}