albumview.java

Android平台上的media player, iPhone风格

/*
 * Copyright (C) 2006 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package com.android.imusic;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.BitmapShader;
import android.graphics.Camera;
import android.graphics.Canvas;
import android.graphics.ComposeShader;
import android.graphics.LinearGradient;
import android.graphics.Paint;
import android.graphics.PorterDuff;
import android.graphics.PorterDuffXfermode;
import android.graphics.Rect;
import android.graphics.Shader;
import android.graphics.Xfermode;
import android.util.AttributeSet;
import android.util.Log;
import android.widget.RelativeLayout;


public class AlbumView extends RelativeLayout
{
    public AlbumView(Context context)
    {
        super(context);
        setWillNotDraw(false);
    }

    public AlbumView(Context context, AttributeSet attrs)
    {
        super(context, attrs);
        setWillNotDraw(false);
    }

    public void setArtwork(Bitmap art)
    {
        mScale = 1.00f;
        cX = 0f;
        cY = 0f;
        cR = 0f; // 24f;

        if (art == null) {
            BitmapFactory.Options opts = new BitmapFactory.Options();
            opts.inPreferredConfig = Bitmap.Config.ARGB_8888;
            art = BitmapFactory.decodeResource(getResources(), R.drawable.albumart_mp_unknown, opts);
        }
        
        if (art != null) {
            mBit = art; // Bitmap.createBitmap(art, 2, 2, art.width()-4, art.height()-4);
            mCoverPaint = new Paint();
            //mCoverPaint.setAntiAlias(true);
            mCoverPaint.setFilterBitmap(true);
            mCoverPaint.setDither(true);

            BitmapShader sh1 = new BitmapShader(mBit, Shader.TileMode.REPEAT, Shader.TileMode.REPEAT);
            LinearGradient sh2 = new LinearGradient(0f, mBit.getHeight(),0f, mBit.getHeight()/3, 0x7f000000, 0x00000000, Shader.TileMode.CLAMP);
            Xfermode mode = new PorterDuffXfermode(PorterDuff.Mode.DST_IN);
            mReflectionShader = new ComposeShader(sh1, sh2, mode );

            mCamera = new Camera();
            mCamera.rotateY(cR);
            mCamera.translate(cX,cY,0);
        }
    }

    private void drawArtwork(Canvas canvas)
    {
        if (mBit == null)
            return;

        canvas.save();

        mCamera.applyToCanvas(canvas);

        int mywidth = getWidth();
        float artwidth = mBit.getWidth();
//        float scale = ((float)(mywidth - mPaddingLeft - mPaddingRight))/artwidth * mScale;
//
//        canvas.translate(mPaddingLeft, mPaddingTop);

//        canvas.scale(scale, scale);
        mCoverPaint.setAlpha(255);
        canvas.drawBitmap(mBit,0f,0f, mCoverPaint);
        
        if (false) {
            // draw the reflection
            canvas.scale(1, -1, 0, mBit.getHeight());
            mCoverPaint.setAlpha(64);
            mCoverPaint.setShader(mReflectionShader);
            canvas.drawRect(new Rect(0,0,mBit.getWidth(),mBit.getHeight()), mCoverPaint); 
            mCoverPaint.setShader(null);
        }

        canvas.restore();
    }

    @Override
    protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);

        drawArtwork(canvas);
    }

    void adjustParams(double scale, double ix, double iy, double cx, double cy, double cr)
    {
        mScale += scale;
//        mPaddingLeft += ix;
//        mPaddingTop += iy;
        cX += cx;
        cY += cy;
        cR += cr;

        mCamera.rotateY((float)cr); // little r
        mCamera.translate((float)cx,(float)cy,0); // little too

//        System.out.println("parameters: "
//              + mScale + " "
//              + mPaddingLeft + " "
//              + mPaddingTop + " "
//              + cX + " "
//              + cY + " "
//              + cR + " ");
        invalidate();
    }

    private Bitmap mBit;
    private Paint mCoverPaint;
    private Camera mCamera;
    private ComposeShader mReflectionShader;

    float mScale;
    float cX;
    float cY;
    float cR;
}