CenteredTextIconButton.java

/**
 * @author Jonathan
 * 
 *         Initial claas by Phillip Calvin
 */

package com.abewy.android.apps.klyph.view;

import android.content.Context;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.widget.Button;

public class CenteredTextIconButton extends Button
{
	protected int				drawableWidth;
	protected DrawablePositions	drawablePosition;
	protected int				iconPadding;

	// Cached to prevent allocation during onLayout
	Rect						bounds;

	private enum DrawablePositions
	{
		NONE,
		LEFT,
		RIGHT
	}

	public CenteredTextIconButton(Context context)
	{
		super(context);
		bounds = new Rect();
	}

	public CenteredTextIconButton(Context context, AttributeSet attrs)
	{
		super(context, attrs);
		bounds = new Rect();
	}

	public CenteredTextIconButton(Context context, AttributeSet attrs, int defStyle)
	{
		super(context, attrs, defStyle);
		bounds = new Rect();
	}

	public void setIconPadding(int padding)
	{
		iconPadding = padding;
		requestLayout();
	}

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

		Paint textPaint = getPaint();
		String text = getText().toString();
		textPaint.getTextBounds(text, 0, text.length(), bounds);

		int textWidth = bounds.width();
		int contentWidth = drawableWidth + iconPadding + textWidth;

		int contentLeft = (int) ((getWidth() / 2.0) - (contentWidth / 2.0));
		setCompoundDrawablePadding(-contentLeft + iconPadding);
		switch (drawablePosition)
		{
			case LEFT:
				setPadding(contentLeft, 0, 0, 0);
				break;
			case RIGHT:
				setPadding(0, 0, contentLeft, 0);
				break;
			default:
				setPadding(0, 0, 0, 0);
		}
	}

	@Override
	public void setCompoundDrawablesWithIntrinsicBounds(Drawable left, Drawable top, Drawable right, Drawable bottom)
	{
		super.setCompoundDrawablesWithIntrinsicBounds(left, top, right, bottom);
		if (null != left)
		{
			drawableWidth = left.getIntrinsicWidth();
			drawablePosition = DrawablePositions.LEFT;
		}
		else if (null != right)
		{
			drawableWidth = right.getIntrinsicWidth();
			drawablePosition = DrawablePositions.RIGHT;
		}
		else
		{
			drawablePosition = DrawablePositions.NONE;
		}
		requestLayout();
	}
}