您好，我正在建立一项偏好活动，在该活动中SwitchPreference我启用了一些EditTexts。当开关被选中AlertDialog时，用户可以选择主密码。如果用户没有选择密码，我希望再次禁用该开关。
代码：
@TargetApi(Build.VERSION_CODES.HONEYCOMB)
public static class GeneralPreferenceFragment extends PreferenceFragment implements View.OnClickListener {
private AlertDialog pinDialog;
private SwitchPreference master;
private boolean updated;
private SharedPreferences mUpdated;
private SharedPreferences.Editor mEditor;
private Button one, two, three, four, five, six, seven, eight, nine, zero, buttonClicked, openButton, settings;
private ImageView image1, image2, image3, image4;
private TextView tv;
private AlertDialog.Builder builder;
private StringBuffer pinCode, checkPinCode;
private int count = 0;
private String encryptedString;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
addPreferencesFromResource(R.xml.pref_general);
setHasOptionsMenu(true);
master = (SwitchPreference) findPreference("master_switch");
mUpdated = PreferenceManager.getDefaultSharedPreferences(getActivity().getApplicationContext());
updated = mUpdated.getBoolean("master_switch", false);
pinDialog = enablePinDialog();
pinCode = new StringBuffer();
checkPinCode = new StringBuffer();
setListeners();
bindPreferenceSummaryToValue(findPreference("coffees_file"));
bindPreferenceSummaryToValue(findPreference("snacks_file"));
bindPreferenceSummaryToValue(findPreference("sweets_file"));
bindPreferenceSummaryToValue(findPreference("spirits_file"));
bindPreferenceSummaryToValue(findPreference("beverages_file"));
bindPreferenceSummaryToValue(findPreference("beers_file"));
master.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() {
@Override
public boolean onPreferenceChange(Preference preference, Object newValue) {
boolean switched = ((SwitchPreference) preference).isChecked();
updated = !switched;
mEditor = mUpdated.edit();
mEditor.putBoolean("master_switch", updated);
mEditor.apply();
master.setSummary(!updated ? "Disabled" : "Enabled");
if (updated) {
if (pinDialog != null) {
pinDialog.show();
}
} else {
removePrefs();
}
return true;
}
});
}
private void setListeners() {
one.setOnClickListener(this);
two.setOnClickListener(this);
three.setOnClickListener(this);
four.setOnClickListener(this);
five.setOnClickListener(this);
six.setOnClickListener(this);
seven.setOnClickListener(this);
eight.setOnClickListener(this);
nine.setOnClickListener(this);
zero.setOnClickListener(this);
}
public AlertDialog enablePinDialog() {
builder = new AlertDialog.Builder(getActivity());
View view = LayoutInflater.from(builder.getContext()).inflate(R.layout.dialog_layout, null, false);
one = (Button) view.findViewById(R.id.button);
two = (Button) view.findViewById(R.id.button2);
three = (Button) view.findViewById(R.id.button3);
four = (Button) view.findViewById(R.id.button4);
five = (Button) view.findViewById(R.id.button5);
six = (Button) view.findViewById(R.id.button6);
seven = (Button) view.findViewById(R.id.button7);
eight = (Button) view.findViewById(R.id.button8);
nine = (Button) view.findViewById(R.id.button9);
zero = (Button) view.findViewById(R.id.buttonzero);
image1 = (ImageView) view.findViewById(R.id.imageView);
image2 = (ImageView) view.findViewById(R.id.imageView2);
image3 = (ImageView) view.findViewById(R.id.imageView3);
image4 = (ImageView) view.findViewById(R.id.imageView4);
tv = (TextView) view.findViewById(R.id.changeText);
builder.setView(view);
builder.setTitle("Master Password");
return builder.create();
}
private void savePassword() {
SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(getActivity());
SharedPreferences.Editor editor = preferences.edit();
MessageDigest messageDigest;
try {
messageDigest = MessageDigest.getInstance("SHA-256");
messageDigest.update(checkPinCode.toString().getBytes());
encryptedString = new String(messageDigest.digest());
} catch (NoSuchAlgorithmException e) {
e.printStackTrace();
}
editor.putString("master_pin", encryptedString);
editor.apply();
}
private void removePrefs() {
SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(getActivity());
SharedPreferences.Editor editor = preferences.edit();
editor.remove("master_pin");
editor.apply();
}
private void typePassword() {
count++;
pinCode.append(String.valueOf(buttonClicked.getText()));
if (count == 1) {
image1.setImageResource(R.drawable.ic_lens_black_24dp);
} else if (count == 2) {
image2.setImageResource(R.drawable.ic_lens_black_24dp);
} else if (count == 3) {
image3.setImageResource(R.drawable.ic_lens_black_24dp);
} else if (count == 4) {
image4.setImageResource(R.drawable.ic_lens_black_24dp);
image1.setImageResource(R.drawable.ic_radio_button_unchecked_black_24dp);
image2.setImageResource(R.drawable.ic_radio_button_unchecked_black_24dp);
image3.setImageResource(R.drawable.ic_radio_button_unchecked_black_24dp);
image4.setImageResource(R.drawable.ic_radio_button_unchecked_black_24dp);
tv.setText(R.string.second_text);
}
}
private void retypePassword() {
checkPinCode.append(String.valueOf(buttonClicked.getText()));
if (count == 5) {
image1.setImageResource(R.drawable.ic_lens_black_24dp);
} else if (count == 6) {
image2.setImageResource(R.drawable.ic_lens_black_24dp);
} else if (count == 7) {
image3.setImageResource(R.drawable.ic_lens_black_24dp);
} else if (count == 8) {
image4.setImageResource(R.drawable.ic_lens_black_24dp);
checkPinCode = checkPinCode.delete(0, 4);
pinCode = pinCode.delete(4, 8);
Log.e("1st Try", pinCode.toString());
Log.e("2nd Try", checkPinCode.toString());
if (checkPinCode.toString().equals(pinCode.toString())) {
tv.setText(R.string.second_text);
Toast.makeText(getActivity(), "Master Password created", Toast.LENGTH_SHORT).show();
savePassword();
pinDialog.dismiss();
} else {
tv.setText(R.string.first_text);
Toast.makeText(getActivity(), "Pins don't match", Toast.LENGTH_SHORT).show();
count = 0;
image1.setImageResource(R.drawable.ic_radio_button_unchecked_black_24dp);
image2.setImageResource(R.drawable.ic_radio_button_unchecked_black_24dp);
image3.setImageResource(R.drawable.ic_radio_button_unchecked_black_24dp);
image4.setImageResource(R.drawable.ic_radio_button_unchecked_black_24dp);
pinCode.delete(0, pinCode.length());
checkPinCode.delete(0, checkPinCode.length());
pinDialog.dismiss();
}
}
}
编辑：使用 Ajit Pratap Singh 回答
master.setOnPreferenceChangeListener(new Preference.OnPreferenceChangeListener() { @Override public boolean onPreferenceChange(Preference preference, Object newValue) {
final boolean switched = ((SwitchPreference) preference).isChecked();
updated = !switched;
mEditor = mUpdated.edit();
mEditor.putBoolean("master_switch", updated);
Log.e("Switch is", String.valueOf(updated));
mEditor.apply();
master.setSummary(!updated ? "Disabled" : "Enabled");
if (updated) {
if (pinDialog != null) {
pinDialog.show();
}
} else {
removePrefs();
}
pinDialog.setOnDismissListener(new DialogInterface.OnDismissListener() {
@Override
public void onDismiss(DialogInterface dialog) {
updated = switched;
mEditor = mUpdated.edit();
mEditor.putBoolean("master_switch", updated);
Log.e("Switch after dismiss", String.valueOf(updated));
mEditor.apply();
master.setSummary(!updated ? "Disabled" : "Enabled");
}
});
return true;
}
});
结果是开关被禁用但指示灯亮：
当我通过返回对话框将其关闭时，它被禁用，但是当我创建主密码时，它仍然保持禁用状态。这是由于master.setChecked(false);这条线。如果我删除它，当我关闭它时它仍然保持启用状态。