Android how to make button text bold when pressed or focussed

I want to change the text inside a button to be bold when the button is highlighted or pressed. I currently use a xml file to define the button and use the XML to change how it looks when pressed but I would like to do this without using an image.

<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schema开发者_运维技巧s.android.com/apk/res/android">
    <item android:state_focused="true"
          android:state_pressed="false" 
          android:drawable="@drawable/reset_hover" />
    <item android:state_focused="true" 
          android:state_pressed="true"
          android:drawable="@drawable/reset_hover" />
    <item android:state_focused="false" 
          android:state_pressed="true"
      android:drawable="@drawable/reset_hover" />
    <item android:drawable="@drawable/reset" />
</selector>

I tried using something like the following, but it doesn't seem to ever get called.

    final Button btn_reset = (Button) findViewById(R.id.btn_reset);
    btn_reset.setOnClickListener(this); 
    btn_reset.setOn(new OnFocusChangeListener() {
    @Override
    public void onFocusChange(View v, boolean hasFocus) {
        if (hasFocus){btn_reset.setTypeface(null, Typeface.BOLD);}
        else{btn_reset.setTypeface(null, Typeface.NORMAL);}
    }
   });

You could try putting the bold code inside the click event for the button:

final Button button = (Button) findViewById(R.id.button_id);
         button.setOnClickListener(new View.OnClickListener() {
             public void onClick(View v) {
                 // Set bold on click
                 button.setTypeface(null, Typeface.BOLD);
             }
         });

Attention! See update below

You could create your own style.xml in which you define the text style. In your selector you can reference to the style. style.xml

<style name="myStyle">  
    <item name="android:textSize">9px</item>
    <item name="android:gravity">center_horizontal</item>
    <item name="android:textColor">#fff</item>
    <item name="android:textStyle">bold</item>
</style>

And in your selector

<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item android:state_focused="true"
      android:state_pressed="false" 
      style="@style/myStyle" /> </selector>

Update 2020: My answer is more than 10 years old. It doesn´t work anymore!

Styles are not allowed in selectors. Reference

And to make the text bold, use this code:

btn_reset.setOnTouchListener(new View.OnTouchListener() {
    @Override
    public boolean onTouch(View v, MotionEvent event) {

        switch (event.getAction()) {
            // When the user clicks the Button
            case MotionEvent.ACTION_DOWN:
                btn_reset.setTypeface(Typeface.DEFAULT_BOLD);
                break;

            // When the user releases the Button
            case MotionEvent.ACTION_UP:
                btn_reset.setTypeface(Typeface.DEFAULT);
                break;
        }
        return false;
    }
});