android酷炫翻页效果+图形分析

package sf.hmg.turntest;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.ColorMatrix;
import android.graphics.ColorMatrixColorFilter;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.Path;
import android.graphics.PointF;
import android.graphics.Region;
import android.graphics.drawable.GradientDrawable;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Scroller;

public class PageWidget extends View {

    private static final String TAG = "hmg";
    private int mWidth = 480;
    private int mHeight = 800;
    private int mCornerX = 0; // 拖拽点对应的页脚
    private int mCornerY = 0;
    private Path mPath0;
    private Path mPath1;
    Bitmap mCurPageBitmap = null; // 当前页
    Bitmap mNextPageBitmap = null;

    PointF mTouch = new PointF(); // 拖拽点
    PointF mBezierStart1 = new PointF(); // 贝塞尔曲线起始点
    PointF mBezierControl1 = new PointF(); // 贝塞尔曲线控制点
    PointF mBeziervertex1 = new PointF(); // 贝塞尔曲线顶点
    PointF mBezierEnd1 = new PointF(); // 贝塞尔曲线结束点

    PointF mBezierStart2 = new PointF(); // 另一条贝塞尔曲线
    PointF mBezierControl2 = new PointF();
    PointF mBeziervertex2 = new PointF();
    PointF mBezierEnd2 = new PointF();

    float mMiddleX;
    float mMiddleY;
    float mDegrees;
    float mTouchToCornerDis;
    ColorMatrixColorFilter mColorMatrixFilter;
    Matrix mMatrix;
    float[] mMatrixArray = { 0, 0, 0, 0, 0, 0, 0, 0, 1.0f };

    boolean mIsRTandLB; // 是否属于右上左下
    float mMaxLength = (float) Math.hypot(mWidth, mHeight);
    int[] mBackShadowColors;
    int[] mFrontShadowColors;
    GradientDrawable mBackShadowDrawableLR;
    GradientDrawable mBackShadowDrawableRL;
    GradientDrawable mFolderShadowDrawableLR;
    GradientDrawable mFolderShadowDrawableRL;

    GradientDrawable mFrontShadowDrawableHBT;
    GradientDrawable mFrontShadowDrawableHTB;
    GradientDrawable mFrontShadowDrawableVLR;
    GradientDrawable mFrontShadowDrawableVRL;

Paint mPaint;

Scroller mScroller;

    public PageWidget(Context context) {
        super(context);
        // TODO Auto-generated constructor stub
        mPath0 = new Path();
        mPath1 = new Path();
        createDrawable();

mPaint = new Paint();
mPaint.setStyle(Paint.Style.FILL);

        ColorMatrix cm = new ColorMatrix();
        float array[] = { 0.55f, 0, 0, 0, 80.0f, 0, 0.55f, 0, 0, 80.0f, 0, 0,
                0.55f, 0, 80.0f, 0, 0, 0, 0.2f, 0 };
        cm.set(array);
        mColorMatrixFilter = new ColorMatrixColorFilter(cm);
        mMatrix = new Matrix();
        mScroller = new Scroller(getContext());

        mTouch.x = 0.01f; // 不让x,y为0,否则在点计算时会有问题
        mTouch.y = 0.01f;
    }

    /**
     * Author : hmg25 Version: 1.0 Description : 计算拖拽点对应的拖拽脚
     */
    public void calcCornerXY(float x, float y) {
        if (x <= mWidth / 2)
            mCornerX = 0;
        else
            mCornerX = mWidth;
        if (y <= mHeight / 2)
            mCornerY = 0;
        else
            mCornerY = mHeight;
        if ((mCornerX == 0 && mCornerY == mHeight)
                || (mCornerX == mWidth && mCornerY == 0))
            mIsRTandLB = true;
        else
            mIsRTandLB = false;
    }

    public boolean doTouchEvent(MotionEvent event) {
        // TODO Auto-generated method stub
        if (event.getAction() == MotionEvent.ACTION_MOVE) {
            mTouch.x = event.getX();
            mTouch.y = event.getY();
            this.postInvalidate();
        }
        if (event.getAction() == MotionEvent.ACTION_DOWN) {
            mTouch.x = event.getX();
            mTouch.y = event.getY();
            // calcCornerXY(mTouch.x, mTouch.y);
            // this.postInvalidate();
        }
        if (event.getAction() == MotionEvent.ACTION_UP) {
            if (canDragOver()) {
                startAnimation(1200);
            } else {
                mTouch.x = mCornerX - 0.09f;
                mTouch.y = mCornerY - 0.09f;
            }

            this.postInvalidate();
        }

补充：移动开发 , Android ,