How to have Image and Text Center within a Button

You can fake it by making a more complex layout, but I'm not sure whether it's worth it. Here's something I hacked together:

<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content">
<Button
    android:layout_height="wrap_content"
    android:layout_width="fill_parent"
    android:layout_alignTop="@+id/foreground"
    android:layout_alignBottom="@id/foreground"
    android:layout_alignRight="@id/foreground"
    android:layout_alignLeft="@id/foreground"
    android:onClick="clickedMe" />
   <RelativeLayout
        android:id="@id/foreground"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content">
    <TextView  
        android:id="@+id/button_text"
        android:layout_width="wrap_content" 
        android:layout_height="wrap_content"
        android:layout_centerInParent="true" 
        android:text="@string/hello" />
    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_centerVertical="true"
        android:layout_toLeftOf="@id/button_text"
        android:paddingTop="10dip"
        android:paddingBottom="10dip"
        android:src="@drawable/icon" />
</RelativeLayout>
</RelativeLayout>

There might be a more concise way to do it. I tend to struggle getting RelativeLayout to do what I want sometimes. Note that you need to pay attention to the z-order (Button needs to appear first in the top level RelativeLayout) and you might need to adjust padding to get it to look the way you want.

Similar to some other approaches, I think a good solution is to extend Button and add the missing functionality by overriding its onLayout method:

public class CenteredIconButton extends Button {
    private static final int LEFT = 0, TOP = 1, RIGHT = 2, BOTTOM = 3;

    // Pre-allocate objects for layout measuring
    private Rect textBounds = new Rect();
    private Rect drawableBounds = new Rect();

    public CenteredIconButton(Context context) {
        this(context, null);
    }

    public CenteredIconButton(Context context, AttributeSet attrs) {
        this(context, attrs, android.R.attr.buttonStyle);
    }

    public CenteredIconButton(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);
    }

    @Override
    protected void onLayout(boolean changed, int left, int top, int right, int bottom) {
        super.onLayout(changed, left, top, right, bottom);

        if (!changed) return;

        final CharSequence text = getText();
        if (!TextUtils.isEmpty(text)) {
            TextPaint textPaint = getPaint();
            textPaint.getTextBounds(text.toString(), 0, text.length(), textBounds);
        } else {
            textBounds.setEmpty();
        }

        final int width = getWidth() - (getPaddingLeft() + getPaddingRight());

        final Drawable[] drawables = getCompoundDrawables();

        if (drawables[LEFT] != null) {
            drawables[LEFT].copyBounds(drawableBounds);
            int leftOffset =
                    (width - (textBounds.width() + drawableBounds.width()) + getRightPaddingOffset()) / 2 - getCompoundDrawablePadding();
            drawableBounds.offset(leftOffset, 0);
            drawables[LEFT].setBounds(drawableBounds);
        }

        if (drawables[RIGHT] != null) {
            drawables[RIGHT].copyBounds(drawableBounds);
            int rightOffset =
                    ((textBounds.width() + drawableBounds.width()) - width + getLeftPaddingOffset()) / 2 + getCompoundDrawablePadding();
            drawableBounds.offset(rightOffset, 0);
            drawables[RIGHT].setBounds(drawableBounds);
        }
    }
}

The sample only works for left and right drawables, but could be extended to adjust top and bottom drawables too.