使用片段中的共享首选项更改字体大小

Question

I am changing the size of a TextView with a Shared Preference. I am absolutely sure that I have written the codes in settings correctly, so I am just not sure about my fragment that whether or not it is correct. I was wondering if someone would mind recognizing the problem and correcting it please. Thanks

prefsize = this.getActivity().getSharedPreferences(prefnamesize, Context.MODE_PRIVATE);
tx.setTextSize(prefsize.getFloat(FONT_SIZE_KEY, 25));

Answer 1

This is not the right/best practice for this purpose

Store all the text size or anything related to 'dp' or 'sp' in dimen.xml in values folder

Example :

dimen.xml

<resources>
    <dimen name="textSizeMedium">16sp</dimen>
</resources>

Access this to your layout file:

<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    ...

    <TextView
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:textSize="@dimen/textSizeMedium" />  // <----- This is the way

    ...

</FrameLayout>

or in Java code dynamically (Activity)

tx.setTextSize(getResources().getDimension(R.dimen.textSizeMedium));

(Fragment)

tx.setTextSize(getActivity().getResources().getDimension(R.dimen.textSizeMedium));

Answer 2

It is maybe too late, but I found the way. In your dimens.xml has to go like this

<resources>
<dimen name="code_editor_size1">11sp</dimen>
</resources>

Then, in Java, when the user press the size Button, need to go this

settings.edit().putString("textSize", String.valueOf((long)((float)getResources().getDimension(R.dimen.code_editor_size1)))).commit(); 

And finally, to use in the text view

if (settings.getString("textSize", "").equals("")) {
    
}
else {
    textSize = Double.parseDouble(settings.getString("textSize", ""));
    code.setTextSize(TypedValue.COMPLEX_UNIT_PX, (float)textSize);
}

I want to mention that when I get the value, I got it with a Double variable, that was the only way I could have done this, and code is an id of an edit text