How do I reduce the inner padding around the text within an Android button object?

It took me forever to find this but the "padding" around the text in a button isn't really padding at all. The default Widget.Button style includes a minHeight property. Changing minHeight on the button will allow you to adjust padding as expected.

<Button
        android:id="@+id/header"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:text="@string/test"
        android:textColor="@color/black"
        android:minHeight="40dip"/>


<style name="Widget.Holo.Button" parent="Widget.Button">
    <item name="android:background">@android:drawable/btn_default_holo_dark</item>
    <item name="android:textAppearance">?android:attr/textAppearanceMedium</item>
    <item name="android:textColor">@android:color/primary_text_holo_dark</item>
    <item name="android:minHeight">48dip</item>
    <item name="android:minWidth">64dip</item>
</style>

In the Material Components Library, the MaterialButton has a default style with insetBottom and insetTop with a value of 6dp.

You can change them in the layout:

  <com.google.android.material.button.MaterialButton
      android:insetTop="0dp"
      android:insetBottom="0dp"
      ../>

or in a style:

 <style name="Button_no_insets" parent="Widget.MaterialComponents.Button"..>
    <item name="android:insetTop">0dp</item>
    <item name="android:insetBottom">0dp</item>
 </style>

try this in your custom shape.xml file

<shape xmlns:android="http://schemas.android.com/apk/res/android"
android:shape="rectangle"
android:paddingLeft="10dp"
android:paddingRight="10dp"
android:paddingTop="1dp"
android:padding="1dp">

also you can make change in your button's xml

android:layout_width="wrap_content"
android:layout_height="wrap_content"