我是通过Android Studio进行设置活动的,而不是手动进行的。我想进行一个在应用程序中应用暗模式的开关。问题是,当我单击开关时,没有动画可移动,而应用程序只眨了眨眼。当我回到主要活动时,我看到应用了主题(我之前只在主要活动中尝试过),但是当我尝试返回设置时,一切都冻结了!什么都没有点击,根本没有反应。这是我的Java代码:
import androidx.appcompat.app.ActionBar;
import androidx.appcompat.app.AppCompatActivity;
import androidx.appcompat.app.AppCompatDelegate;
import androidx.preference.Preference;
import androidx.preference.PreferenceFragmentCompat;
import androidx.preference.SwitchPreference;
public class SettingsActivity extends AppCompatActivity {
private SwitchPreference darkModeSwitch;
@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);
SwitchPreference darkModeSwitch = (SwitchPreference) findPreference("darkmode");
assert darkModeSwitch != null;
darkModeSwitch.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
@Override
public boolean onPreferenceChange(Preference preference, Object newValue) {
if (AppCompatDelegate.getDefaultNightMode() == AppCompatDelegate.MODE_NIGHT_YES) {
AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_NO);
} else {
AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_YES);
}
return false;
}
});
}
}
}
这是root_preferences.xml:
<PreferenceScreen
xmlns:app="http://schemas.android.com/apk/res-auto">
<PreferenceCategory
app:title="General">
<SwitchPreference
app:key="darkmode"
app:title="Dark mode"/>
</PreferenceCategory>
这是应用主题后的Logcat:
avc: denied { getattr } for path="/proc/1" dev="proc" ino=3924 scontext=u:r:untrusted_app:s0:c512,c768 tcontext=u:r:init:s0 tclass=dir permissive=0
我认为这可能是因为我在应用主题之后没有再次开始该活动,因为当我在main_activity中尝试暗模式时,有两行内容无法放置在我的设置活动中,因为该类是静态的...请帮助!
public void onClick(View v) {
if (AppCompatDelegate.getDefaultNightMode() == AppCompatDelegate.MODE_NIGHT_YES) {
AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_NO);
} else {
AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_YES);
}
//These two
finish();
startActivity(new Intent(MainActivity.this, MainActivity.this.getClass()));
}
});
将其放入您的preferences.xml
:
<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:app="http://schemas.android.com/apk/res-auto">
<SwitchPreferenceCompat
app:defaultValue="false"
app:key="@string/key_night_mode"
app:summaryOff="@string/summary_night_mode_off"
app:summaryOn="@string/summary_night_mode_on"
app:title="@string/title_night_mode" />
</PreferenceScreen>
然后在SettingsFragment.java
中用PreferenceFragmentCompat
方法扩展了onCreatePreference()
:
SwitchPreferenceCompat switchPreferenceCompat = findPreference(getString(R.string.key_night_mode));
switchPreferenceCompat.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
@Override
public boolean onPreferenceChange(Preference preference, Object newValue) {
boolean isChecked = false;
if (newValue instanceof Boolean)
isChecked = (Boolean) newValue;
if (isChecked) {
//these lines so that the preference persists
getPreferenceManager().getSharedPreferences().edit().putBoolean(getString(R.string.key_night_mode), true).apply();
//you do not need to finish and recreate activity
//it takes care of any such things that needs to be done
//automatically
AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_YES);
} else {
getPreferenceManager().getSharedPreferences().edit().putBoolean(getString(R.string.key_night_mode), false).apply();
AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_NO);
}
return true;
}
});
这些代码行对我有用。
注意:
AppTheme
应从Theme.AppCompat.DayNight
或Theme.MaterialComponents.DayNight
扩展,如果您希望依赖平台作为夜间主题。否则,您可以创建分别从Day
和Night
扩展的单独的Theme.MaterialComponents.Light
和Theme.MaterialComponents
主题(AppCompat
也具有相似的主题集)。每次启动应用程序时,它都需要尊重用户的偏好,并相应地以用户设置的主题开始。为此,您可以检查首选项并在MyApplication
类中设置主题,如下所示:
SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
boolean nightMode = sharedPreferences.getBoolean(getString(R.string.key_night_mode), false);
if (nightMode)
AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_YES);
else {
if (Build.VERSION.SDK_INT <= Build.VERSION_CODES.P)
AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_AUTO_BATTERY);
else
AppCompatDelegate.setDefaultNightMode(AppCompatDelegate.MODE_NIGHT_FOLLOW_SYSTEM);
}