android 电子书阅读器源码下载

【实例截图】

【核心代码】

package com.kaixinbook;

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;

/**
 * 控制页面画出贝塞尔曲线
 * 
 * @author yuanhang
 * 
 */
public class PageWidget extends View {

	private int mScreenWidth = 480; // 屏幕宽
	private int mScreenHeight = 800; // 屏幕高
	private int mCornerX = 1; // 拖拽点对应的页脚
	private int mCornerY = 1;
	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(mScreenWidth, mScreenHeight);
	int[] mBackShadowColors;// 背面颜色组
	int[] mFrontShadowColors;// 前面颜色组
	GradientDrawable mBackShadowDrawableLR; // 有阴影的GradientDrawable
	GradientDrawable mBackShadowDrawableRL;
	GradientDrawable mFolderShadowDrawableLR;
	GradientDrawable mFolderShadowDrawableRL;

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

	Paint mPaint;
	Scroller mScroller;

	public PageWidget(Context context, int width, int height) {
		super(context);
		mPath0 = new Path();
		mPath1 = new Path();
		mScreenWidth = width;
		mScreenHeight = height;

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

		createDrawable();

		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;
	}

	/**
	 * 计算拖拽点对应的拖拽脚
	 * 
	 * @param x
	 * @param y
	 */
	public void calcCornerXY(float x, float y) {
		if (x <= mScreenWidth / 2)
			mCornerX = 0;
		else
			mCornerX = mScreenWidth;
		if (y <= mScreenHeight / 2)
			mCornerY = 0;
		else
			mCornerY = mScreenHeight;
		if ((mCornerX == 0 && mCornerY == mScreenHeight)
				|| (mCornerX == mScreenWidth && mCornerY == 0))
			mIsRTandLB = true;
		else
			mIsRTandLB = false;
	}

	public boolean doTouchEvent(MotionEvent event) {

		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 - 10f;
			// mTouch.y = mCornerY - 10f;
			// }
			// 直接画出动画而不使用时上面的条件判断
			startAnimation(1200);
			this.postInvalidate();
		}
		// return super.onTouchEvent(event);
		return true;
	}

	/**
	 * 求解直线P1P2和直线P3P4的交点坐标
	 * 
	 * @param P1
	 * @param P2
	 * @param P3
	 * @param P4
	 * @return
	 */
	public PointF getCross(PointF P1, PointF P2, PointF P3, PointF P4) {
		PointF CrossP = new PointF();
		// 二元函数通式： y=ax b
		float a1 = (P2.y - P1.y) / (P2.x - P1.x);
		float b1 = ((P1.x * P2.y) - (P2.x * P1.y)) / (P1.x - P2.x);

		float a2 = (P4.y - P3.y) / (P4.x - P3.x);
		float b2 = ((P3.x * P4.y) - (P4.x * P3.y)) / (P3.x - P4.x);
		CrossP.x = (b2 - b1) / (a1 - a2);
		CrossP.y = a1 * CrossP.x   b1;
		return CrossP;
	}

	private void calcPoints() {
		mMiddleX = (mTouch.x   mCornerX) / 2;
		mMiddleY = (mTouch.y   mCornerY) / 2;
		mBezierControl1.x = mMiddleX - (mCornerY - mMiddleY)
				* (mCornerY - mMiddleY) / (mCornerX - mMiddleX);
		mBezierControl1.y = mCornerY;
		mBezierControl2.x = mCornerX;
		mBezierControl2.y = mMiddleY - (mCornerX - mMiddleX)
				* (mCornerX - mMiddleX) / (mCornerY - mMiddleY);

		// Log.i("hmg", "mTouchX  "   mTouch.x   "  mTouchY  "   mTouch.y);
		// Log.i("hmg", "mBezierControl1.x  "   mBezierControl1.x
		//   "  mBezierControl1.y  "   mBezierControl1.y);
		// Log.i("hmg", "mBezierControl2.x  "   mBezierControl2.x
		//   "  mBezierControl2.y  "   mBezierControl2.y);

		mBezierStart1.x = mBezierControl1.x - (mCornerX - mBezierControl1.x)
				/ 2;
		mBezierStart1.y = mCornerY;

		// 当mBezierStart1.x < 0或者mBezierStart1.x > 480时
		// 如果继续翻页，会出现BUG故在此限制
		if (mTouch.x > 0 && mTouch.x < mScreenWidth) {
			if (mBezierStart1.x < 0 || mBezierStart1.x > mScreenWidth) {
				if (mBezierStart1.x < 0)
					mBezierStart1.x = mScreenWidth - mBezierStart1.x;

				float f1 = Math.abs(mCornerX - mTouch.x);
				float f2 = mScreenWidth * f1 / mBezierStart1.x;
				mTouch.x = Math.abs(mCornerX - f2);

				float f3 = Math.abs(mCornerX - mTouch.x)
						* Math.abs(mCornerY - mTouch.y) / f1;
				mTouch.y = Math.abs(mCornerY - f3);

				mMiddleX = (mTouch.x   mCornerX) / 2;
				mMiddleY = (mTouch.y   mCornerY) / 2;

				mBezierControl1.x = mMiddleX - (mCornerY - mMiddleY)
						* (mCornerY - mMiddleY) / (mCornerX - mMiddleX);
				mBezierControl1.y = mCornerY;

				mBezierControl2.x = mCornerX;
				mBezierControl2.y = mMiddleY - (mCornerX - mMiddleX)
						* (mCornerX - mMiddleX) / (mCornerY - mMiddleY);
				// Log.i("hmg", "mTouchX --> "   mTouch.x   "  mTouchY-->  "
				//   mTouch.y);
				// Log.i("hmg", "mBezierControl1.x--  "   mBezierControl1.x
				//   "  mBezierControl1.y -- "   mBezierControl1.y);
				// Log.i("hmg", "mBezierControl2.x -- "   mBezierControl2.x
				//   "  mBezierControl2.y -- "   mBezierControl2.y);
				mBezierStart1.x = mBezierControl1.x
						- (mCornerX - mBezierControl1.x) / 2;
			}
		}
		mBezierStart2.x = mCornerX;
		mBezierStart2.y = mBezierControl2.y - (mCornerY - mBezierControl2.y)
				/ 2;

		mTouchToCornerDis = (float) Math.hypot((mTouch.x - mCornerX),
				(mTouch.y - mCornerY));

		mBezierEnd1 = getCross(mTouch, mBezierControl1, mBezierStart1,
				mBezierStart2);
		mBezierEnd2 = getCross(mTouch, mBezierControl2, mBezierStart1,
				mBezierStart2);

		// Log.i("hmg", "mBezierEnd1.x  "   mBezierEnd1.x   "  mBezierEnd1.y  "
		//   mBezierEnd1.y);
		// Log.i("hmg", "mBezierEnd2.x  "   mBezierEnd2.x   "  mBezierEnd2.y  "
		//   mBezierEnd2.y);

		/*
		 * mBeziervertex1.x 推导
		 * ((mBezierStart1.x mBezierEnd1.x)/2 mBezierControl1.x)/2 化简等价于
		 * (mBezierStart1.x  2*mBezierControl1.x mBezierEnd1.x) / 4
		 */
		mBeziervertex1.x = (mBezierStart1.x   2 * mBezierControl1.x   mBezierEnd1.x) / 4;
		mBeziervertex1.y = (2 * mBezierControl1.y   mBezierStart1.y   mBezierEnd1.y) / 4;
		mBeziervertex2.x = (mBezierStart2.x   2 * mBezierControl2.x   mBezierEnd2.x) / 4;
		mBeziervertex2.y = (2 * mBezierControl2.y   mBezierStart2.y   mBezierEnd2.y) / 4;
	}

	private void drawCurrentPageArea(Canvas canvas, Bitmap bitmap, Path path) {
		mPath0.reset();
		mPath0.moveTo(mBezierStart1.x, mBezierStart1.y);
		mPath0.quadTo(mBezierControl1.x, mBezierControl1.y, mBezierEnd1.x,
				mBezierEnd1.y);
		mPath0.lineTo(mTouch.x, mTouch.y);
		mPath0.lineTo(mBezierEnd2.x, mBezierEnd2.y);
		mPath0.quadTo(mBezierControl2.x, mBezierControl2.y, mBezierStart2.x,
				mBezierStart2.y);
		mPath0.lineTo(mCornerX, mCornerY);
		mPath0.close();

		canvas.save();
		canvas.clipPath(path, Region.Op.XOR);
		canvas.drawBitmap(bitmap, 0, 0, null);
		canvas.restore();
	}

	private void drawNextPageAreaAndShadow(Canvas canvas, Bitmap bitmap) {
		mPath1.reset();
		mPath1.moveTo(mBezierStart1.x, mBezierStart1.y);
		mPath1.lineTo(mBeziervertex1.x, mBeziervertex1.y);
		mPath1.lineTo(mBeziervertex2.x, mBeziervertex2.y);
		mPath1.lineTo(mBezierStart2.x, mBezierStart2.y);
		mPath1.lineTo(mCornerX, mCornerY);
		mPath1.close();

		mDegrees = (float) Math.toDegrees(Math.atan2(mBezierControl1.x
				- mCornerX, mBezierControl2.y - mCornerY));
		int leftx;
		int rightx;
		GradientDrawable mBackShadowDrawable;
		if (mIsRTandLB) {
			leftx = (int) (mBezierStart1.x);
			rightx = (int) (mBezierStart1.x   mTouchToCornerDis / 4);
			mBackShadowDrawable = mBackShadowDrawableLR;
		} else {
			leftx = (int) (mBezierStart1.x - mTouchToCornerDis / 4);
			rightx = (int) mBezierStart1.x;
			mBackShadowDrawable = mBackShadowDrawableRL;
		}
		canvas.save();
		canvas.clipPath(mPath0);
		canvas.clipPath(mPath1, Region.Op.INTERSECT);
		canvas.drawBitmap(bitmap, 0, 0, null);
		canvas.rotate(mDegrees, mBezierStart1.x, mBezierStart1.y);
		mBackShadowDrawable.setBounds(leftx, (int) mBezierStart1.y, rightx,
				(int) (mMaxLength   mBezierStart1.y));
		mBackShadowDrawable.draw(canvas);
		canvas.restore();
	}

	public void setBitmaps(Bitmap bm1, Bitmap bm2) {
		mCurPageBitmap = bm1;
		mNextPageBitmap = bm2;
	}

	public void setScreen(int w, int h) {
		mScreenWidth = w;
		mScreenHeight = h;
	}

	@Override
	protected void onDraw(Canvas canvas) {
		canvas.drawColor(0xFFAAAAAA);
		calcPoints();
		drawCurrentPageArea(canvas, mCurPageBitmap, mPath0);
		drawNextPageAreaAndShadow(canvas, mNextPageBitmap);
		drawCurrentPageShadow(canvas);
		drawCurrentBackArea(canvas, mCurPageBitmap);
	}

	/**
	 * 创建阴影的GradientDrawable
	 */
	private void createDrawable() {
		int[] color = { 0x333333, 0xb0333333 };
		mFolderShadowDrawableRL = new GradientDrawable(
				GradientDrawable.Orientation.RIGHT_LEFT, color);
		mFolderShadowDrawableRL
				.setGradientType(GradientDrawable.LINEAR_GRADIENT);

		mFolderShadowDrawableLR = new GradientDrawable(
				GradientDrawable.Orientation.LEFT_RIGHT, color);
		mFolderShadowDrawableLR
				.setGradientType(GradientDrawable.LINEAR_GRADIENT);

		mBackShadowColors = new int[] { 0xff111111, 0x111111 };
		mBackShadowDrawableRL = new GradientDrawable(
				GradientDrawable.Orientation.RIGHT_LEFT, mBackShadowColors);
		mBackShadowDrawableRL.setGradientType(GradientDrawable.LINEAR_GRADIENT);

		mBackShadowDrawableLR = new GradientDrawable(
				GradientDrawable.Orientation.LEFT_RIGHT, mBackShadowColors);
		mBackShadowDrawableLR.setGradientType(GradientDrawable.LINEAR_GRADIENT);

		mFrontShadowColors = new int[] { 0x80111111, 0x111111 };
		mFrontShadowDrawableVLR = new GradientDrawable(
				GradientDrawable.Orientation.LEFT_RIGHT, mFrontShadowColors);
		mFrontShadowDrawableVLR
				.setGradientType(GradientDrawable.LINEAR_GRADIENT);
		mFrontShadowDrawableVRL = new GradientDrawable(
				GradientDrawable.Orientation.RIGHT_LEFT, mFrontShadowColors);
		mFrontShadowDrawableVRL
				.setGradientType(GradientDrawable.LINEAR_GRADIENT);

		mFrontShadowDrawableHTB = new GradientDrawable(
				GradientDrawable.Orientation.TOP_BOTTOM, mFrontShadowColors);
		mFrontShadowDrawableHTB
				.setGradientType(GradientDrawable.LINEAR_GRADIENT);

		mFrontShadowDrawableHBT = new GradientDrawable(
				GradientDrawable.Orientation.BOTTOM_TOP, mFrontShadowColors);
		mFrontShadowDrawableHBT
				.setGradientType(GradientDrawable.LINEAR_GRADIENT);
	}

	/**
	 * 绘制翻起页的阴影
	 * 
	 * @param canvas
	 */
	public void drawCurrentPageShadow(Canvas canvas) {
		double degree;
		if (mIsRTandLB) {
			degree = Math.PI
					/ 4
					- Math.atan2(mBezierControl1.y - mTouch.y, mTouch.x
							- mBezierControl1.x);
		} else {
			degree = Math.PI
					/ 4
					- Math.atan2(mTouch.y - mBezierControl1.y, mTouch.x
							- mBezierControl1.x);
		}
		// 翻起页阴影顶点与touch点的距离
		double d1 = (float) 25 * 1.414 * Math.cos(degree);
		double d2 = (float) 25 * 1.414 * Math.sin(degree);
		float x = (float) (mTouch.x   d1);
		float y;
		if (mIsRTandLB) {
			y = (float) (mTouch.y   d2);
		} else {
			y = (float) (mTouch.y - d2);
		}
		mPath1.reset();
		mPath1.moveTo(x, y);
		mPath1.lineTo(mTouch.x, mTouch.y);
		mPath1.lineTo(mBezierControl1.x, mBezierControl1.y);
		mPath1.lineTo(mBezierStart1.x, mBezierStart1.y);
		mPath1.close();
		float rotateDegrees;
		canvas.save();

		canvas.clipPath(mPath0, Region.Op.XOR);
		canvas.clipPath(mPath1, Region.Op.INTERSECT);
		int leftx;
		int rightx;
		GradientDrawable mCurrentPageShadow;
		if (mIsRTandLB) {
			leftx = (int) (mBezierControl1.x);
			rightx = (int) mBezierControl1.x   25;
			mCurrentPageShadow = mFrontShadowDrawableVLR;
		} else {
			leftx = (int) (mBezierControl1.x - 25);
			rightx = (int) mBezierControl1.x   1;
			mCurrentPageShadow = mFrontShadowDrawableVRL;
		}

		rotateDegrees = (float) Math.toDegrees(Math.atan2(mTouch.x
				- mBezierControl1.x, mBezierControl1.y - mTouch.y));
		canvas.rotate(rotateDegrees, mBezierControl1.x, mBezierControl1.y);
		mCurrentPageShadow.setBounds(leftx,
				(int) (mBezierControl1.y - mMaxLength), rightx,
				(int) (mBezierControl1.y));
		mCurrentPageShadow.draw(canvas);
		canvas.restore();

		mPath1.reset();
		mPath1.moveTo(x, y);
		mPath1.lineTo(mTouch.x, mTouch.y);
		mPath1.lineTo(mBezierControl2.x, mBezierControl2.y);
		mPath1.lineTo(mBezierStart2.x, mBezierStart2.y);
		mPath1.close();
		canvas.save();
		canvas.clipPath(mPath0, Region.Op.XOR);
		canvas.clipPath(mPath1, Region.Op.INTERSECT);
		if (mIsRTandLB) {
			leftx = (int) (mBezierControl2.y);
			rightx = (int) (mBezierControl2.y   25);
			mCurrentPageShadow = mFrontShadowDrawableHTB;
		} else {
			leftx = (int) (mBezierControl2.y - 25);
			rightx = (int) (mBezierControl2.y   1);
			mCurrentPageShadow = mFrontShadowDrawableHBT;
		}
		rotateDegrees = (float) Math.toDegrees(Math.atan2(mBezierControl2.y
				- mTouch.y, mBezierControl2.x - mTouch.x));
		canvas.rotate(rotateDegrees, mBezierControl2.x, mBezierControl2.y);
		float temp;
		if (mBezierControl2.y < 0)
			temp = mBezierControl2.y - mScreenHeight;
		else
			temp = mBezierControl2.y;

		int hmg = (int) Math.hypot(mBezierControl2.x, temp);
		if (hmg > mMaxLength)
			mCurrentPageShadow
					.setBounds((int) (mBezierControl2.x - 25) - hmg, leftx,
							(int) (mBezierControl2.x   mMaxLength) - hmg,
							rightx);
		else
			mCurrentPageShadow.setBounds(
					(int) (mBezierControl2.x - mMaxLength), leftx,
					(int) (mBezierControl2.x), rightx);

		// Log.i("hmg", "mBezierControl2.x   "   mBezierControl2.x
		//   "  mBezierControl2.y  "   mBezierControl2.y);
		mCurrentPageShadow.draw(canvas);
		canvas.restore();
	}

	/**
	 * 绘制翻起页背面
	 * 
	 * @param canvas
	 * @param bitmap
	 */
	private void drawCurrentBackArea(Canvas canvas, Bitmap bitmap) {
		int i = (int) (mBezierStart1.x   mBezierControl1.x) / 2;
		float f1 = Math.abs(i - mBezierControl1.x);
		int i1 = (int) (mBezierStart2.y   mBezierControl2.y) / 2;
		float f2 = Math.abs(i1 - mBezierControl2.y);
		float f3 = Math.min(f1, f2);
		mPath1.reset();
		mPath1.moveTo(mBeziervertex2.x, mBeziervertex2.y);
		mPath1.lineTo(mBeziervertex1.x, mBeziervertex1.y);
		mPath1.lineTo(mBezierEnd1.x, mBezierEnd1.y);
		mPath1.lineTo(mTouch.x, mTouch.y);
		mPath1.lineTo(mBezierEnd2.x, mBezierEnd2.y);
		mPath1.close();
		GradientDrawable mFolderShadowDrawable;
		int left;
		int right;
		if (mIsRTandLB) {
			left = (int) (mBezierStart1.x - 1);
			right = (int) (mBezierStart1.x   f3   1);
			mFolderShadowDrawable = mFolderShadowDrawableLR;
		} else {
			left = (int) (mBezierStart1.x - f3 - 1);
			right = (int) (mBezierStart1.x   1);
			mFolderShadowDrawable = mFolderShadowDrawableRL;
		}
		canvas.save();
		canvas.clipPath(mPath0);
		canvas.clipPath(mPath1, Region.Op.INTERSECT);

		mPaint.setColorFilter(mColorMatrixFilter);

		float dis = (float) Math.hypot(mCornerX - mBezierControl1.x,
				mBezierControl2.y - mCornerY);
		float f8 = (mCornerX - mBezierControl1.x) / dis;
		float f9 = (mBezierControl2.y - mCornerY) / dis;
		mMatrixArray[0] = 1 - 2 * f9 * f9;
		mMatrixArray[1] = 2 * f8 * f9;
		mMatrixArray[3] = mMatrixArray[1];
		mMatrixArray[4] = 1 - 2 * f8 * f8;
		mMatrix.reset();
		mMatrix.setValues(mMatrixArray);
		mMatrix.preTranslate(-mBezierControl1.x, -mBezierControl1.y);
		mMatrix.postTranslate(mBezierControl1.x, mBezierControl1.y);
		canvas.drawBitmap(bitmap, mMatrix, mPaint);
		// canvas.drawBitmap(bitmap, mMatrix, null);
		mPaint.setColorFilter(null);
		canvas.rotate(mDegrees, mBezierStart1.x, mBezierStart1.y);
		mFolderShadowDrawable.setBounds(left, (int) mBezierStart1.y, right,
				(int) (mBezierStart1.y   mMaxLength));
		mFolderShadowDrawable.draw(canvas);
		canvas.restore();
	}

	public void computeScroll() {
		super.computeScroll();
		if (mScroller.computeScrollOffset()) {
			float x = mScroller.getCurrX();
			float y = mScroller.getCurrY();
			mTouch.x = x;
			mTouch.y = y;
			postInvalidate();
		}
	}

	private void startAnimation(int delayMillis) {
		int dx, dy;
		// dx 水平方向滑动的距离，负值会使滚动向左滚动
		// dy 垂直方向滑动的距离，负值会使滚动向上滚动
		if (mCornerX > 0) {
			dx = -(int) (mScreenWidth   mTouch.x);
		} else {
			dx = (int) (mScreenWidth - mTouch.x   mScreenWidth);
		}
		if (mCornerY > 0) {
			dy = (int) (mScreenHeight - mTouch.y);
		} else {
			dy = (int) (1 - mTouch.y); // 防止mTouch.y最终变为0
		}
		mScroller.startScroll((int) mTouch.x, (int) mTouch.y, dx, dy,
				delayMillis);
	}

	public void abortAnimation() {
		if (!mScroller.isFinished()) {
			mScroller.abortAnimation();
		}
	}

	/**
	 * 是否能够拖动过去
	 * 
	 * @return
	 */
	public boolean canDragOver() {
		if (mTouchToCornerDis > mScreenWidth / 10)
			return true;
		return false;
	}

	/**
	 * 是否从左边翻向右边
	 * 
	 * @return
	 */
	public boolean DragToRight() {
		if (mCornerX > 0)
			return false;
		return true;
	}

}