SoundView.java

/**
 *
 * Copyright  2014  Djia
 * All right reserved.
 * 
 * Author: Djia, Created on 2014-6-30
 */
package com.wind.gifassistant.views;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.media.AudioManager;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.View;

import com.wind.gifassistant.R;
import com.wind.gifassistant.utils.AppConfigs;

/**
 * @author Djia
 * 2014-6-30
 */

public class SoundView extends View {
	public final static String TAG = AppConfigs.APP_TAG + "SoundView";
	
	private Context mContext;
	private Bitmap bm , bm1;
	private int bitmapWidth , bitmapHeight;
	private int index;
	private OnVolumeChangedListener mOnVolumeChangedListener;
	
	private final static int HEIGHT = 11;
	public final static int MY_HEIGHT = 163;
	public final static int MY_WIDTH = 44;
	
	public interface OnVolumeChangedListener{
		public void setVolume(int index);
	}
	
	public void setOnVolumeChangeListener(OnVolumeChangedListener l){
		mOnVolumeChangedListener = l;
	}

	/**
	 * @param context
	 */
	public SoundView(Context context) {
		super(context);
		// TODO Auto-generated constructor stub
		mContext = context;
		init();
	}

	/**
	 * @param context
	 * @param attrs
	 */
	public SoundView(Context context, AttributeSet attrs) {
		super(context, attrs);
		// TODO Auto-generated constructor stub
		mContext = context;
		init();
	}

	/**
	 * @param context
	 * @param attrs
	 * @param defStyle
	 */
	public SoundView(Context context, AttributeSet attrs, int defStyle) {
		super(context, attrs, defStyle);
		// TODO Auto-generated constructor stub
		mContext = context;
		init();
	}

	private void init(){
		bm = BitmapFactory.decodeResource(mContext.getResources(), R.mipmap.sound_line);
		bm1 = BitmapFactory.decodeResource(mContext.getResources(), R.mipmap.sound_line1);
		bitmapWidth = bm.getWidth();
		bitmapHeight = bm.getHeight();
		//setIndex(5);
		AudioManager am = (AudioManager) mContext.getSystemService(Context.AUDIO_SERVICE);
		setIndex(am.getStreamVolume(AudioManager.STREAM_MUSIC));
	}
	
	@Override
	public boolean onTouchEvent(MotionEvent event) { 
		// TODO Auto-generated method stub
		
		int y = (int) event.getY();
		int n = y * 15 / MY_HEIGHT;
		setIndex(15-n);
		Log.d(TAG, "setIndex: "+(15-n));
		
		
		return true;
	}

	@Override
	protected void onDraw(Canvas canvas) {
		// TODO Auto-generated method stub

		int reverseIndex = 15 - index;
		for(int i = 0;i!=reverseIndex;++i){
			canvas.drawBitmap(bm1, new Rect(0,0,bitmapWidth,bitmapHeight), 
					new Rect(0,i*HEIGHT,bitmapWidth,i*HEIGHT+bitmapHeight), null);
		}
		for(int i = reverseIndex;i!=15;++i){
			canvas.drawBitmap(bm, new Rect(0,0,bitmapWidth,bitmapHeight), 
					new Rect(0,i*HEIGHT,bitmapWidth,i*HEIGHT+bitmapHeight), null);
		}
		
		super.onDraw(canvas);  
	}

	private void setIndex(int n){
		if(n>15){
			n = 15;
		}
		else if(n<0){
			n = 0;
		}
		if(index!=n){
			index = n;
			if(mOnVolumeChangedListener!=null){
				mOnVolumeChangedListener.setVolume(n);
			}
		}
		invalidate();
	}
	
}