Question

我已经制作了4个单选按钮，并希望在单击任何一个时保存状态，然后想要在应用程序中使用该已保存的状态。我该怎么办？

                    myOption1.setChecked(true);
        myOption2.setChecked(true);
        myOption3.setChecked(true);
        myOption4.setChecked(true);

Answer 1

如果你只有4个单选按钮，你可以将它们的“值”存储在SharedPreferences（持久存储）中。

示例：

SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);
SharedPreferences.Editor shEditor = sharedPreferences.edit();

shEditor.putBoolean("checkbox_1", myOptionOne.isChecked());
shEditor.putBoolean("checkbox_2", myOptionTwo.isChecked());
shEditor.putBoolean("checkbox_3", myOptionThree.isChecked());
shEditor.putBoolean("checkbox_4", myOptionFour.isChecked());

shEditor.commit();

通过执行以下操作来使用它：

SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(this);

 myOptionOne.setChecked(sharedPreferences.getBoolean("checkbox_1", false));
 myOptionTwo.setChecked(sharedPreferences.getBoolean("checkbox_2", false));
 myOptionThree.setChecked(sharedPreferences.getBoolean("checkbox_3", false));
 myOptionFour.setChecked(sharedPreferences.getBoolean("checkbox_4", false));

Answer 2

在您的活动中覆盖onSaveInstanceState()和onRestoreInstanceState()。

@Override
public void onSaveInstanceState(Bundle savedInstanceState) {
  super.onSaveInstanceState(savedInstanceState);
  savedInstanceState.putBoolean("myOption1", myOption1.isChecked());
  savedInstanceState.putBoolean("myOption2", myOption2.isChecked());
  savedInstanceState.putBoolean("myOption3", myOption3.isChecked());
  savedInstanceState.putBoolean("myOption4", myOption4.isChecked());
}

@Override
public void onRestoreInstanceState(Bundle savedInstanceState) {
  super.onRestoreInstanceState(savedInstanceState);
  myOption1.setChecked(savedInstanceState.getBoolean("myOption1"));
  myOption2.setChecked(savedInstanceState.getBoolean("myOption2"));
  myOption3.setChecked(savedInstanceState.getBoolean("myOption3"));
  myOption4.setChecked(savedInstanceState.getBoolean("myOption4"));
}

Answer 3

将该值保存在sharedPreferences概念中。此处放置了示例示例，该示例使用名为addPreferencesFromResource（）的预定义方法，该方法将自动获取复选框值的状态并保存在首选项中。

    public class EditPreference extends PreferenceActivity {

        @Override
        protected void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            //setContentView(R.layout.checkboxpref);
            addPreferencesFromResource(R.layout.checkboxpref);
        }
    }

布局代码应为：

<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android.com/apk/res/android"

    android:key="@string/checkbox_pref"

    android:title="@string/eidt_preferences">

<CheckBoxPreference

    android:key="@string/pref_12_time_format"

    android:title="@string/time_formats"

    android:summary="@string/twelve_hour" 

    android:defaultValue="true"/>

<CheckBoxPreference

    android:key="@string/pref_show_current_location"

    android:title="@string/show_current_location"

    android:summary="@string/using_gps_network" 

    android:defaultValue="true"/>

<CheckBoxPreference

    android:key="@string/pref_display_date"

    android:title="@string/display_date"

    android:defaultValue="true"/>

</PreferenceScreen>

现在你已经检索了这个存储的复选框值如下：

SharedPreferences sharedPreference = PreferenceManager
                .getDefaultSharedPreferences(getApplicationContext());
        mTimeFormat = sharedPreference.getBoolean("pref_12_time_format", false);
        mServiceType = sharedPreference.getBoolean(
                "pref_show_current_location", false);
        mDisplayDate = sharedPreference.getBoolean("pref_display_date", false);

如何保存单选按钮的状态

3 个答案: