点击图片中不规则图形提示选中不同区域

package com.bitcare.view;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;

public class NavMapView extends View {

	private Bitmap[] mBitmaps;
	private OnClickBitmapListener clickBitmapListener;

	public NavMapView(Context context) {
		super(context);
	}

	public NavMapView(Context context, AttributeSet attrs) {
		super(context, attrs);
	}

	/**
	 * 设置图片
	 * @author yubin
	 * @date 2013-10-12
	 */
	public final void setBitmaps(Bitmap[] bitmap) {
		this.mBitmaps = bitmap;
		invalidate();
	}

	@Override
	protected void onDraw(Canvas canvas) {
		super.onDraw(canvas);
		if (mBitmaps != null) {
			for (int i = 0; i < mBitmaps.length; i++) {
				canvas.drawBitmap(mBitmaps[i], 0, 0, null);
			}
		}
	}

	@Override
	public boolean onTouchEvent(MotionEvent event) {
		if (event.getAction() == MotionEvent.ACTION_DOWN) {
			which(event.getX(), event.getY());
		}
		return true;
	}

	public void which(float x, float y) {
		if (mBitmaps != null) {
			for (int i = 0; i < mBitmaps.length; i++) {
				// 判断坐标点不超过图片得宽高
				if ((int) x > mBitmaps[0].getWidth() || (int) y > mBitmaps[0].getHeight()) {
					clickBitmapListener.ClickBitmap(-1);
					break;
				}
				Bitmap mBitmap = mBitmaps[i];
				// 判断坐标点是否是在图片得透明区域
				if (mBitmap.getPixel((int) x, (int) y) != 0) {
					clickBitmapListener.ClickBitmap(i);
					break;
				}
			}
		}
	}

	public final void setOnClickBitmapListener(OnClickBitmapListener listener) {
		this.clickBitmapListener = listener;
	};

	public static interface OnClickBitmapListener {
		/**
		 * @param index -1表示超出范围
		 * @author yubin
		 * @date 2013-10-12
		 */
		void ClickBitmap(int index);
	}
}