如何通过按钮更改 TextView 的字体大小？

Question

I'm making a calculator app and I am trying to make it so that the CA (clear all) button resets the size of the text shown in the input and output spaces. Because I set the text in the input and output spaces to autosize depending on the length of the equation and answer, the font size stays decreased on my next input and output as well. Is there a way to make the button revert the text back to it's original size?

TextView for input

<TextView
            android:layout_weight="1"
            android:id="@+id/input"
            android:layout_width="match_parent"
            android:layout_height="80dp"
            android:autoSizeTextType="uniform"
            android:autoSizePresetSizes="@array/text_sizes"
            android:maxLength="10"
            android:background="@color/black"
            android:fontFamily="@font/lgc"
            android:gravity="end"
            android:ellipsize="end"
            android:padding="20dp"
            android:text=""
            android:textColor="@color/white"
            android:textSize="30sp" />

Answer 1

You can use setTextSize(unit, size) under button click event:

yourTextViewID.setTextSize(TypedValue.COMPLEX_UNIT_SP, 18f);

ReferDoc