package com.inks.jisaimedicalforch8.view;
import android.animation.Animator;
import android.animation.ValueAnimator;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
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.Rect;
import android.graphics.RectF;
import android.graphics.Shader;
import android.os.Handler;
import android.os.Message;
import android.support.annotation.Nullable;
import 
 
android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.view.View;
import android.view.ViewConfiguration;
import android.view.animation.AccelerateDecelerateInterpolator;
import android.view.animation.Interpolator;
import com.inks.inkslibrary.utils.L;
 
import com.inks.jisaimedicalforch8.UI.R;
/**
 * Created by inks on 2018/6/29 0029.
 */
public class SlideUnlockView extends View {
    public interface UnlockListener {
        void onUnlock();
}

    private UnlockListener mUnlockListener;
    public void setUnlockListener(UnlockListener unlockListener) {
        mUnlockListener = unlockListener;
}

    private static final int MSG_REDRAW = 1;
    private static final int DRAW_INTERVAL = 50;
    private static final int STEP_LENGTH = 10;//速度
private Paint mPaint;//文字的畫筆
private Paint mSliPaint;//滑塊畫筆
private Paint mBgPaint;//背景畫筆
private VelocityTracker mVelocityTracker;//滑動速度
private int mMaxVelocity;
    private LinearGradient mGradient;//漸變色
private LinearGradient bgGradient;//背景漸變色
private LinearGradient sliGradient;//滑塊漸變色
//    LinearGradient有兩個建構函式;
//
//    public LinearGradient(float x0, float y0, float x1, float y1, int[] colors, float[] positions,Shader.TileMode tile)
//
//    引數:
//
//    float x0: 漸變起始點x座標
//
//    float y0:漸變起始點y座標
//
//    float x1:漸變結束點x座標
//
//    float y1:漸變結束點y座標
//
//    int[] colors:顏色 的int 陣列
//
//    float[] positions: 相對位置的顏色陣列,可為null,  若為null,可為null,顏色沿漸變線均勻分佈
//
//    Shader.TileMode tile: 渲染器平鋪模式
//
//
//
//    public LinearGradient(float x0, float y0, float x1, float y1, int color0, int color1,Shader.TileMode tile)
//
//    float x0: 漸變起始點x座標
//
//    float y0:漸變起始點y座標
//
//    float x1:漸變結束點x座標
//
//    float y1:漸變結束點y座標
//
//    int color0: 起始漸變色
//    int color1: 結束漸變色
//
//    Shader.TileMode tile: 渲染器平鋪模式
private int[] mGradientColors;
    private int[] bgGradientColors;
    private int mGradientIndex;
    private Interpolator mInterpolator;
    private float mDensity;
    private Matrix mMatrix;
    private ValueAnimator mValueAnimator;
    private int width;
    private int height;
    private String mText;//文字
private int mTextSize;//文字大小
private int mTextLeft;//文字距離左邊
private int mR;//滑塊的半徑
private float margin;
    private Rect mSliderRect;
    private int mSlidableLength;    // SlidableLength = BackgroundWidth - LeftMagins - RightMagins - SliderWidth
private int mEffectiveLength;   // Suggested length is 20pixels shorter than SlidableLength
private float mEffectiveVelocity = 1000;//滑塊自動回滾的速度
private float mStartX;
    private float mStartY;
    private float mLastX;
    private float mMoveX;
    public SlideUnlockView(Context context) {
        this(context, null);
}

    public SlideUnlockView(Context context, AttributeSet attrs) {
        this(context, attrs, 0);
}

    public SlideUnlockView(Context context, AttributeSet attrs, int defStyleAttr) {
        this(context, attrs, defStyleAttr, 0);
}

    public SlideUnlockView(Context context, AttributeSet attrs, int defStyleAttr, int defStyleRes) {
        super(context, attrs, defStyleAttr, defStyleRes);
mDensity = getResources().getDisplayMetrics().density;
ViewConfiguration configuration = ViewConfiguration.get(context);
mMaxVelocity = configuration.getScaledMaximumFlingVelocity();
mInterpolator = new AccelerateDecelerateInterpolator();
setClickable(true);
setFocusable(true);
setFocusableInTouchMode(true);
mSlidableLength = 200;
mText = ">> 滑動進入主頁";
mTextSize = 36;//文字大小
mTextLeft = 50;//文字距離左邊
mMoveX = 0;
mGradientIndex = 0;
mSliPaint = new Paint();
mSliPaint.setAntiAlias(true);
mBgPaint = new Paint();
mBgPaint.setAntiAlias(true);
mPaint = new Paint();
mPaint.setTextSize(mTextSize);
//該方法即為設定基線上那個點究竟是left,center,還是right
mPaint.setTextAlign(Paint.Align.LEFT);
//  mHandler.sendEmptyMessageDelayed(MSG_REDRAW, DRAW_INTERVAL);
}

    @Override
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
        int specWidthSize = MeasureSpec.getSize(widthMeasureSpec);//寬
int specHeightSize = MeasureSpec.getSize(heightMeasureSpec);//高
mMatrix = new Matrix();
width = specWidthSize;
height = specHeightSize;
mTextLeft = (int) (height * 1.5);
margin = height / 20;
mR = (int) (((height-margin*2) / 2)-margin);
mSlidableLength = (int) (specWidthSize -mR*2-margin*4);
mEffectiveLength = mSlidableLength-20;
mSliderRect = new Rect((int) margin,(int) margin, (int) (mR*2+ margin*2),
(int) (mR*2+ margin*2));
mGradientColors = new int[]{Color.argb(255, 120, 120, 120),
Color.argb(255, 120, 120, 120), Color.argb(255, 255, 255, 255)};
mGradient = new LinearGradient(0, 0, width/2, 0, mGradientColors,
                new float[]{0, 0.7f, 1}, Shader.TileMode.MIRROR);
bgGradient = new LinearGradient(
                0, 0, 0, (float) ((height)/2.0),
Color.argb(80, 0X77, 0X77, 0X77), Color.argb(200, 0X11, 0X11, 0X11),
Shader.TileMode.CLAMP
);
sliGradient = new LinearGradient(
                0, 0, 0, (float) ((height)/2.0),
Color.argb(80, 0Xbb, 0Xbb, 0Xbb), Color.argb(200, 0X77, 0X77, 0X77),
Shader.TileMode.CLAMP
);
//        bgGradientColors = new int[]{Color.argb(80, 0X77, 0X77, 0X77),
//                Color.argb(200, 0X11, 0X11, 0X11), Color.argb(80, 0X77, 0X77, 0X77)};
//        bgGradient = new LinearGradient(margin, 0, margin, height-margin, bgGradientColors,
//                new float[]{0, 0.5f, 1}, Shader.TileMode.MIRROR);
mBgPaint.setShader(bgGradient);
mSliPaint.setShader(sliGradient);
mHandler.removeMessages(MSG_REDRAW);
mHandler.sendEmptyMessageDelayed(MSG_REDRAW, DRAW_INTERVAL);
}


    @Override
protected void onDraw(Canvas canvas) {
        super.onDraw(canvas);
RectF oval = new RectF(margin, margin, width - margin, height - margin);// 設定個新的長方形
canvas.drawRoundRect(oval, (float) ((height - margin*2)/2.0),  (float) ((height - margin*2)/2.0), mBgPaint);//第二個引數是x半徑，第三個引數是y半徑
mPaint.setShader(mGradient);
Paint.FontMetrics fontMetrics = mPaint.getFontMetrics();
        float top = fontMetrics.top;//為基線到字型上邊框的距離
float bottom = fontMetrics.bottom;//為基線到字型下邊框的距離
int baseLineY = (int) (height / 2 - top / 2 - bottom / 2);//基線中間點的y軸計算公式
canvas.drawText(mText, mTextLeft, baseLineY, mPaint);
canvas.drawCircle(mR + mMoveX+margin*2, height/2, mR, mSliPaint);
}

    public void reset() {
        if (mValueAnimator != null) {
            mValueAnimator.cancel();
}
        mMoveX = 0;
mPaint.setAlpha(255);
mHandler.removeMessages(MSG_REDRAW);
mHandler.sendEmptyMessageDelayed(MSG_REDRAW,200);
}




    @Override
public boolean onTouchEvent(MotionEvent event) {

        L.e(event.getAction()+"");
// 點選是否在滑塊上
if (event.getAction() != MotionEvent.ACTION_DOWN
&& !mSliderRect.contains((int) mStartX, (int) mStartY)) {
            if (event.getAction() == MotionEvent.ACTION_UP
|| event.getAction() == MotionEvent.ACTION_CANCEL) {
                mHandler.sendEmptyMessageDelayed(MSG_REDRAW, DRAW_INTERVAL);
}
            return super.onTouchEvent(event);
}
        acquireVelocityTrackerAndAddMovement(event);
        switch (event.getAction()) {
            case MotionEvent.ACTION_DOWN:
                mStartX = event.getX();
mStartY = event.getY();
mLastX = mStartX;
mHandler.removeMessages(MSG_REDRAW);
L.e("按下");
                break;
            case MotionEvent.ACTION_MOVE:
                L.e("移動");
mLastX = event.getX();
                if (mLastX > mStartX) {
                    int alpha = (int) (255 - (mLastX - mStartX) * 3 / mDensity);
                    if (alpha > 1) {
                        mPaint.setAlpha(alpha);
} else {
                        mPaint.setAlpha(0);
}

                    if (mLastX - mStartX > mSlidableLength) {
                        mLastX = mStartX + mSlidableLength;
mMoveX = mSlidableLength;
} else {
                        mMoveX = (int) (mLastX - mStartX);
}
                } else {
                    mLastX = mStartX;
mMoveX = 0;
}
                invalidate();
                break;
            case MotionEvent.ACTION_UP:
            case MotionEvent.ACTION_CANCEL:
                L.e("擡起或超出");
mVelocityTracker.computeCurrentVelocity(1000, mMaxVelocity);
                float velocityX = mVelocityTracker.getXVelocity();
L.e("速度"+velocityX);
                if (mLastX - mStartX > mEffectiveLength || velocityX/2 > mEffectiveVelocity) {
                    startAnimator(mLastX - mStartX,  mSlidableLength, velocityX, true);
} else {
                    startAnimator(mLastX - mStartX,  0, velocityX, false);
mHandler.sendEmptyMessageDelayed(MSG_REDRAW, DRAW_INTERVAL);
}
                releaseVelocityTracker();
                break;
}
        return super.onTouchEvent(event);
}

    private void startAnimator(float start, float end, float velocity, boolean isRightMoving) {
        if (velocity < mEffectiveVelocity) {
            velocity = mEffectiveVelocity;
}
        int duration = (int) (Math.abs(end - start) * 1000 / velocity);
mValueAnimator = ValueAnimator.ofFloat(start, end);
mValueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
            @Override
public void onAnimationUpdate(ValueAnimator animation) {
                mMoveX = (Float) animation.getAnimatedValue();
                int alpha = (int) (255 - (mMoveX) * 3 / mDensity);
                if (alpha > 1) {
                    mPaint.setAlpha(alpha);
} else {
                    mPaint.setAlpha(0);
}
                invalidate();
}
        });
mValueAnimator.setDuration(duration);
mValueAnimator.setInterpolator(mInterpolator);
        if (isRightMoving) {
            mValueAnimator.addListener(new Animator.AnimatorListener() {
                @Override
public void onAnimationStart(Animator animation) {
                }

                @Override
public void onAnimationEnd(Animator animation) {
                    L.e("解鎖");
// reset();
if (mUnlockListener != null) {
                        mUnlockListener.onUnlock();
}
                }

                @Override
public void onAnimationCancel(Animator animation) {
                }

                @Override
public void onAnimationRepeat(Animator animation) {
                }
            });
}
        mValueAnimator.start();
}

    private void acquireVelocityTrackerAndAddMovement(MotionEvent ev) {
        if (mVelocityTracker == null) {
            mVelocityTracker = VelocityTracker.obtain();
}
        mVelocityTracker.addMovement(ev);
}

    private void releaseVelocityTracker() {
        if (mVelocityTracker != null) {
            mVelocityTracker.recycle();
mVelocityTracker = null;
}
    }





    private Handler mHandler = new Handler() {

        public void handleMessage(Message msg) {
            super.handleMessage(msg);
            switch (msg.what) {
                case MSG_REDRAW:
                    if(mMatrix==null){
                        mMatrix = new Matrix();
}
                    mMatrix.setTranslate(mGradientIndex, 0);
                    if(mGradient==null){
                        L.e("mGradient空");
mGradientColors = new int[]{Color.argb(255, 120, 120, 120),
Color.argb(255, 120, 120, 120), Color.argb(255, 255, 255, 255)};
mGradient = new LinearGradient(0, 0, width/2, 0, mGradientColors,
                                new float[]{0, 0.7f, 1}, Shader.TileMode.MIRROR);
}

                    mGradient.setLocalMatrix(mMatrix);
invalidate();
mGradientIndex += STEP_LENGTH ;
                    if(mGradientIndex>=Integer.MAX_VALUE){
                        mGradientIndex = 0;
}
                    mHandler.sendEmptyMessageDelayed(MSG_REDRAW, DRAW_INTERVAL);
                    break;
}
        }
    };
}

<com.inks.jisaimedicalforch8.view.SlideUnlockView
android:id="@+id/SlideUnlockView"
android:layout_width="550dp"
android:layout_height="100dp"
android:layout_centerHorizontal="true"
android:layout_marginTop="750dp"
/>