好的,我正在看一本安卓书,他们正在使用扩展PreferenceActivity的类向数独游戏添加设置,该类被意图调用,并且它所做的只是addPreferencesFromResource(R.xml.settings),此方法已被弃用并且不再起作用,这是本书中的代码:

package org.example.sudoku;

import android.os.Bundle;
import android.preference.PreferenceActivity;

public class Prefs extends PreferenceActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // Load the preferences from an XML resource
        addPreferencesFromResource(R.xml.settings);
    }

}


现在,我研究了此问题,发现您必须实例化PreferenceManager才能执行此操作,但是在示例中,我发现它们从PreferenceFragment扩展了Prefs类(而不是本书中的PreferenceActivity),因此我设法在代码如下:

/*
 * this is for use from API version 11 and after...
 *
 */
package org.example.sudoku;

import android.os.Bundle;
import android.preference.PreferenceFragment;
import android.preference.PreferenceManager;

public class Prefs extends PreferenceFragment {

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

        // Make sure default values are applied.  In a real app, you would
        // want this in a shared function that is used to retrieve the
        // SharedPreferences wherever they are needed.
        PreferenceManager.setDefaultValues(getActivity(),
                R.xml.settings, false);

        // Load the preferences from an XML resource
        addPreferencesFromResource(R.xml.settings);
    }

}


但这并不能解决问题,我不知道是否是因为我是从意图中调用此类并且此类扩展了PreferenceFragment而不是PreferenceActivy,或者这不是这样做的方法,有人可以帮我吗明白这一点?

最佳答案

final String PREF_SETTINGS_FILE_NAME = "PrefSettingsFile";


读取您的首选项变量的值。

SharedPreferences preferences = getSharedPreferences(PREF_SETTINGS_FILE_NAME, MODE_PRIVATE);
            prefSettingsValue1=  preferences.getInt("value1", 1); // default value of prefSettingsValue1 will be 1 in case you are trying to read a non-existent value. You can specify it according to your wish. (like I have done for the next value)
            prefSettingsValue2=  preferences.getInt("value2", 0);
            prefSettingsValue3=  preferences.getInt("value3", 1);


将值写入您的首选项变量。

 SharedPreferences preferences = getSharedPreferences(PREF_SETTINGS_FILE_NAME, MODE_PRIVATE);
        SharedPreferences.Editor editor = preferences.edit();
        editor.putInt("vaule1", prefSettingsValue1);
        editor.putInt("value2",prefSettingsValue2);
        editor.putInt("value3",prefSettingsValue3);
        editor.commit();


注意:无需使用任何XML文件来存储首选项。只需将值保存在Preference变量中,然后在应用程序中读取它们。不仅是整数,还可以通过使用getput函数分别读取和写入getStringputString字符串。同样,您不需要扩展任何首选项活动/片段。

10-07 19:15
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