Android实现3D光盘封面画廊效果

package org.pskink; import android.content.Context; import android.content.res.Resources; import android.graphics.Bitmap; import android.graphics.Bitmap.Config; import android.graphics.BitmapFactory; import android.graphics.Canvas; import android.graphics.Color; import android.graphics.LinearGradient; import android.graphics.Matrix; import android.graphics.Paint; import android.graphics.PorterDuff.Mode; import android.graphics.PorterDuffXfermode; import android.graphics.Rect; import android.graphics.RectF; import android.graphics.Shader.TileMode; import android.view.View; import android.view.ViewGroup; import android.widget.BaseAdapter; import android.widget.ImageView; public class Flow3DGalleryAdapter extends BaseAdapter { int mGalleryItemBackground; private Context mContext; private Integer[] mImageIds; private ImageView[] mImages; public Flow3DGalleryAdapter(Context c, Integer[] ImageIds) { mContext = c; mImageIds = ImageIds; mImages = new ImageView[mImageIds.length]; } /** * 创建倒影效果 * @return */ public boolean createReflectedImages() { //倒影图和原图之间的距离 final int reflectionGap = 4; int index = 0; for (int imageId : mImageIds) { //返回原图解码之后的bitmap对象 Bitmap originalImage2 = BitmapFactory.decodeResource(mContext.getResources(), imageId); int width = originalImage2.getWidth(); int height = originalImage2.getHeight(); //创建矩阵对象 Matrix matrix = new Matrix(); //创建圆角图片 Bitmap originalImage = getRoundedCornerBitmap(originalImage2,30); //指定一个角度以0,0为坐标进行旋转 // matrix.setRotate(30); //指定矩阵(x轴不变，y轴相反) matrix.preScale(1, -1); //将矩阵应用到该原图之中，返回一个宽度不变，高度为原图1/2的倒影位图 Bitmap reflectionImage = Bitmap.createBitmap(originalImage, 0, height/2, width, height/2, matrix, false); //创建一个宽度不变，高度为原图+倒影图高度的位图 Bitmap bitmapWithReflection = Bitmap.createBitmap(width, (height + height / 2), Config.ARGB_8888); //将上面创建的位图初始化到画布 Canvas canvas = new Canvas(bitmapWithReflection); canvas.drawBitmap(originalImage, 0, 0, null); canvas.drawBitmap(reflectionImage, 0, height + reflectionGap, null); Paint paint = new Paint(); paint.setAntiAlias(true); /** * 参数一:为渐变起初点坐标x位置， * 参数二:为y轴位置， * 参数三和四:分辨对应渐变终点， * 最后参数为平铺方式， * 这里设置为镜像Gradient是基于Shader类，所以我们通过Paint的setShader方法来设置这个渐变 */ LinearGradient shader = new LinearGradient(0,originalImage.getHeight(), 0, bitmapWithReflection.getHeight() + reflectionGap,0x70ffffff, 0x00ffffff, TileMode.MIRROR); //设置阴影 paint.setShader(shader); paint.setXfermode(new PorterDuffXfermode(android.graphics.PorterDuff.Mode.DST_IN)); //用已经定义好的画笔构建一个矩形阴影渐变效果 canvas.drawRect(0, height, width, bitmapWithReflection.getHeight()+ reflectionGap, paint); //创建一个ImageView用来显示已经画好的bitmapWithReflection ImageView imageView = new ImageView(mContext); imageView.setImageBitmap(bitmapWithReflection); //设置imageView大小 ，也就是最终显示的图片大小 imageView.setLayoutParams(new Flow3DGallery.LayoutParams(200, 200)); //imageView.setScaleType(ScaleType.MATRIX); mImages[index++] = imageView; } return true; } @SuppressWarnings("unused") private Resources getResources() { return null; } public int getCount() { return mImageIds.length; } public Object getItem(int position) { return position; } public long getItemId(int position) { return position; } public View getView(int position, View convertView, ViewGroup parent) { return mImages[position]; } public float getScale(boolean focused, int offset) { return Math.max(0, 1.0f / (float) Math.pow(2, Math.abs(offset))); } //获得圆角图片的方法 public static Bitmap getRoundedCornerBitmap(Bitmap bitmap,float roundPx){ Bitmap output = Bitmap.createBitmap(bitmap.getWidth(), bitmap.getHeight(), Config.ARGB_8888); Canvas canvas = new Canvas(output); final int color = 0xff424242; final Paint paint = new Paint(); final Rect rect = new Rect(0, 0, bitmap.getWidth(), bitmap.getHeight()); // final RectF rectF = new RectF(rect); paint.setAntiAlias(true); canvas.drawARGB(0, 0, 0, 0); paint.setColor(color); canvas.drawCircle(rect.exactCenterX(), rect.exactCenterY(), rect.width()/2, paint); //paint.setColor(Color.argb(255, 45, 0, 0)); //canvas.drawCircle(rect.exactCenterX(), rect.exactCenterY(), rect.width()/6, paint); //canvas.drawRoundRect(rectF, roundPx, roundPx, paint); paint.setXfermode(new PorterDuffXfermode(Mode.SRC_IN)); canvas.drawBitmap(bitmap, rect, rect, paint); paint.setColor(Color.argb(0, 0, 0, 0)); canvas.drawCircle(rect.exactCenterX(), rect.exactCenterY(), rect.width()/6, paint); return output; } }