單擊 android 上的電話硬件后退按鈕時從未調用過 onResume？

Question

我正面臨這個問題，我有 MainActivity 和 SettingsPreference，所以當我從設置返回到 MainActivity 時我想在 MainActivity 上重新加載適配器我使用了 onResume() 當我點擊 ActionBar 后退按鈕時它工作得很好，但是當我在硬件上嘗試它時后退按鈕它從未被調用過，我發現系統調用 onPostResume() 而不是 onResume() 所以嘗試使用它，但從未應用更改

這是我正在使用的 SettingsActivity

當按下 ActionBar 后退按鈕時，此代碼有效

      @Override
          protected void onResume() {
              super.onResume();
              dataFromSharedPrefrence = getSettingsSharedPreferences();
              adapterExample.notifyDataSetChanged();

          }

當硬件后退按鈕被按下但更改從未應用時，系統調用 onPostResume()

@Override
        protected void onPostResume() {
              super.onPostResume();
              dataFromSharedPrefrence = getSettingsSharedPreferences();
              adapterExample.notifyDataSetChanged();
}

這是設置活動

public class SettingsActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.settings_activity);
        getSupportFragmentManager()
                .beginTransaction()
                .replace(R.id.settings, new SettingsFragment())
                .commit();
        ActionBar actionBar = getSupportActionBar();
        if (actionBar != null) {
            actionBar.setDisplayHomeAsUpEnabled(true);
        }
    }


    public static class SettingsFragment extends PreferenceFragmentCompat {
        @Override
        public void onCreatePreferences(Bundle savedInstanceState, String rootKey) {
            setPreferencesFromResource(R.xml.root_preferences, rootKey);
        }
    }

當我覆蓋生命周期方法時，我發現了這種差異

1. 當按下 ActionBar 按鈕時，這是 output

2020-05-05 06:00:44.899 23467-23467/com.example.test E/MainActivity: onDestroy
2020-05-05 06:00:44.907 23467-23467/com.example.test E/MainActivity: onDetachedFromWindow
2020-05-05 06:00:44.964 23467-23467/com.example.test E/MainActivity: onCreateView
2020-05-05 06:00:44.990 23467-23467/com.example.test E/MainActivity: onCreateView
2020-05-05 06:00:45.009 23467-23467/com.example.test E/MainActivity: onCreateView
2020-05-05 06:00:45.015 23467-23467/com.example.test E/MainActivity: onCreateView
2020-05-05 06:00:45.037 23467-23467/com.example.test E/MainActivity: onContentChanged
2020-05-05 06:00:45.048 23467-23467/com.example.test E/MainActivity: onStart
2020-05-05 06:00:45.051 23467-23467/com.example.test E/MainActivity: onPostCreate
2020-05-05 06:00:45.053 23467-23467/com.example.test E/MainActivity: onResume
2020-05-05 06:00:45.056 23467-23467/com.example.test E/MainActivity: onPostResume
2020-05-05 06:00:45.078 23467-23467/com.example.test E/MainActivity: onAttachedToWindow
2020-05-05 06:00:45.141 23467-23467/com.example.test E/MainActivity: onCreateView
2020-05-05 06:00:45.188 23467-23467/com.example.test E/MainActivity: onCreateView
2020-05-05 06:00:45.223 23467-23467/com.example.test E/MainActivity: onCreateView

2. 當按下硬件后退按鈕時，這是 output

2020-05-05 06:01:21.732 23467-23467/com.example.test E/MainActivity: onRestart
2020-05-05 06:01:21.734 23467-23467/com.example.test E/MainActivity: onStart
2020-05-05 06:01:21.738 23467-23467/com.example.test E/MainActivity: onResume
2020-05-05 06:01:21.739 23467-23467/com.example.test E/MainActivity: onPostResume

Answer 1

試試這個：

不要使用onResume()嘗試onStart() ：

  @Override
      protected void onStart() {
          super.onStart();
          dataFromSharedPrefrence = getSettingsSharedPreferences();
          adapterExample.notifyDataSetChanged();

      }