android - kotlin sharedPreferences - Stack Overflow

admin管理员组

文章数量:1345476

In my old java app I had a dropdown from the action bar which presented a choice of adjusting the font size and the font type. This used the PreferenceFragment which has long been deprecated. I am looking for a replacement in kotlin. All I can find in the docs are preferences which is a subset of the Room database. I want to provide an xml of variables and use a preference manager to remember the choice. The journey is: user clicks on actionBar to get a dropdown with two items, font size and font name

<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android=";>
    <ListPreference
        android:entries="@array/font_size"
        android:entryValues="@array/fvalues"
        android:key="fong"
        android:summary="Click here to choose a font size"
        android:title="Select Font Size" />
    <ListPreference
        android:entries="@array/font_name"
        android:entryValues="@array/font_ttf"
        android:key="fonz"
        android:summary="Click here to change font"
        android:title="Select Font" />
</PreferenceScreen>

Depending on your selection you get a choice of resources

<resources>
    <string-array name="font_size">
        <item>Huge</item>
        <item>Large</item>
        <item>Normal</item>
        <item>Small</item>
        <item>Tiny</item>
    </string-array>

    <string-array name="fvalues">
        <item>28</item>
        <item>24</item>
        <item>20</item>
        <item>16</item>
        <item>12</item>
    </string-array>


    <string-array name="font_name">
        <item>Note</item>
        <item>Flower</item>
    </string-array>

    <string-array name="font_ttf">
        <item>Note_this.ttf</item>
        <item>IndieFlower.ttf</item>
    </string-array>

</resources

When the user has selected a font name and font size these are then used across the app.

This is the actionBar code

   public boolean onOptionsItemSelected(MenuItem item) {        
        int itemId = item.getItemId();

        if (itemId == R.id.action_settings) {
            Intent p = new Intent("app.sticky_notes.PREFS");
            startActivity(p);
        }
        return false;
    }

Which calls this class, which presented the user with a second menu. It then saves the choosen preferences.

public class Prefs extends PreferenceActivity
{
    @Override public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        getFragmentManager().beginTransaction().replace(android.R.id.content, new Pref_frag())mit();
    }

    public static class Pref_frag extends PreferenceFragment
    {
        @Override public void onCreate(Bundle savedInstanceState)
        {
            super.onCreate(savedInstanceState);

            addPreferencesFromResource(R.xml.prefs);
        }
    }
}

I then call the Preference manager to get the stored choices

    public int get_font_size() {
        SharedPreferences get_prefs = PreferenceManager.getDefaultSharedPreferences(this);
        String font_string = get_prefs.getString("fong", "24");

        font_size = Integer.parseInt(font_string);

        return font_size;
    }

    public String get_font_name() {
        SharedPreferences get_prefs = PreferenceManager.getDefaultSharedPreferences(this);
        font_name = get_prefs.getString("fonz", "Note_this.ttf");

        return font_name;
    }

In kotlin, as far as I can tell, none of this is possible. All sharedPreferences point back to preferences which is a version of Room database which is used to store user input. I want the dropdown->settings menu->settings value menu so the user can click a radio button.

I don't want user input other than a choice of font size and type.

I must be missing something, can anybody point me in the right direction of a working example?

In my old java app I had a dropdown from the action bar which presented a choice of adjusting the font size and the font type. This used the PreferenceFragment which has long been deprecated. I am looking for a replacement in kotlin. All I can find in the docs are preferences which is a subset of the Room database. I want to provide an xml of variables and use a preference manager to remember the choice. The journey is: user clicks on actionBar to get a dropdown with two items, font size and font name

<?xml version="1.0" encoding="utf-8"?>
<PreferenceScreen xmlns:android="http://schemas.android/apk/res/android">
    <ListPreference
        android:entries="@array/font_size"
        android:entryValues="@array/fvalues"
        android:key="fong"
        android:summary="Click here to choose a font size"
        android:title="Select Font Size" />
    <ListPreference
        android:entries="@array/font_name"
        android:entryValues="@array/font_ttf"
        android:key="fonz"
        android:summary="Click here to change font"
        android:title="Select Font" />
</PreferenceScreen>

Depending on your selection you get a choice of resources

<resources>
    <string-array name="font_size">
        <item>Huge</item>
        <item>Large</item>
        <item>Normal</item>
        <item>Small</item>
        <item>Tiny</item>
    </string-array>

    <string-array name="fvalues">
        <item>28</item>
        <item>24</item>
        <item>20</item>
        <item>16</item>
        <item>12</item>
    </string-array>


    <string-array name="font_name">
        <item>Note</item>
        <item>Flower</item>
    </string-array>

    <string-array name="font_ttf">
        <item>Note_this.ttf</item>
        <item>IndieFlower.ttf</item>
    </string-array>

</resources

When the user has selected a font name and font size these are then used across the app.

This is the actionBar code

   public boolean onOptionsItemSelected(MenuItem item) {        
        int itemId = item.getItemId();

        if (itemId == R.id.action_settings) {
            Intent p = new Intent("app.sticky_notes.PREFS");
            startActivity(p);
        }
        return false;
    }

Which calls this class, which presented the user with a second menu. It then saves the choosen preferences.

public class Prefs extends PreferenceActivity
{
    @Override public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        getFragmentManager().beginTransaction().replace(android.R.id.content, new Pref_frag())mit();
    }

    public static class Pref_frag extends PreferenceFragment
    {
        @Override public void onCreate(Bundle savedInstanceState)
        {
            super.onCreate(savedInstanceState);

            addPreferencesFromResource(R.xml.prefs);
        }
    }
}

I then call the Preference manager to get the stored choices

    public int get_font_size() {
        SharedPreferences get_prefs = PreferenceManager.getDefaultSharedPreferences(this);
        String font_string = get_prefs.getString("fong", "24");

        font_size = Integer.parseInt(font_string);

        return font_size;
    }

    public String get_font_name() {
        SharedPreferences get_prefs = PreferenceManager.getDefaultSharedPreferences(this);
        font_name = get_prefs.getString("fonz", "Note_this.ttf");

        return font_name;
    }

In kotlin, as far as I can tell, none of this is possible. All sharedPreferences point back to preferences which is a version of Room database which is used to store user input. I want the dropdown->settings menu->settings value menu so the user can click a radio button.

I don't want user input other than a choice of font size and type.

I must be missing something, can anybody point me in the right direction of a working example?

• android
• kotlin
• sharedpreferences

Share Improve this question Follow asked 17 hours ago MunterManMunterMan 7522 silver badges1010 bronze badges

Add a comment  | 

1 Answer 1

Sorted by: Reset to default 1

The package android.preference is deprecated in favor of androidx.preference which you can get by including this package in your gradle file

implementation "androidx.preference:preference-ktx:1.2.0"

Where you can then use all the same stuff you used before, you just might have to update some classes.

You can find an example here

本文标签： androidkotlin sharedPreferencesStack Overflow