package yanzhikai.ruler.InnerRulers;
import android.content.Context;
import android.support.annotation.Px;
import android.util.Log;
import android.view.MotionEvent;
import android.view.VelocityTracker;
import android.view.ViewGroup;
import yanzhikai.ruler.BooheeRuler;
/**
* 垂直尺子抽象类
*/
public abstract class VerticalRuler extends InnerRuler {
private final String TAG = "ruler";
//记录落点
private float mLastY = 0;
//一半高度
protected int mHalfHeight = 0;
public VerticalRuler(Context context, BooheeRuler booheeRuler) {
super(context, booheeRuler);
}
//处理滑动，主要是触摸的时候通过计算现在的event坐标和上一个的位移量来决定scrollBy()的多少
//滑动完之后计算速度是否满足Fling，满足则使用OverScroller来计算Fling滑动
@Override
public boolean onTouchEvent(MotionEvent event) {
float currentY = event.getY();
//开始速度检测
if (mVelocityTracker == null) {
mVelocityTracker = VelocityTracker.obtain();
}
mVelocityTracker.addMovement(event);
ViewGroup parent = (ViewGroup) getParent();//为了解决刻度尺在scrollview这种布局里面滑动冲突问题
switch (event.getAction()) {
case MotionEvent.ACTION_DOWN:
if (!mOverScroller.isFinished()) {
mOverScroller.abortAnimation();
}
mLastY = currentY;
parent.requestDisallowInterceptTouchEvent(true);//按下时开始让父控件不要处理任何touch事件
break;
case MotionEvent.ACTION_MOVE:
float moveY = mLastY - currentY;
mLastY = currentY;
scrollBy(0, (int) (moveY));
break;
case MotionEvent.ACTION_UP:
//处理松手后的Fling
mVelocityTracker.computeCurrentVelocity(1000, mMaximumVelocity);
int velocityY = (int) mVelocityTracker.getYVelocity();
if (Math.abs(velocityY) > mMinimumVelocity) {
fling(-velocityY);
} else {
scrollBackToCurrentScale();
}
//VelocityTracker回收
if (mVelocityTracker != null) {
mVelocityTracker.recycle();
mVelocityTracker = null;
}
releaseEdgeEffects();
parent.requestDisallowInterceptTouchEvent(false);//按下时开始让父控件不要处理任何touch事件
break;
case MotionEvent.ACTION_CANCEL:
if (!mOverScroller.isFinished()) {
mOverScroller.abortAnimation();
}
scrollBackToCurrentScale();
//VelocityTracker回收
if (mVelocityTracker != null) {
mVelocityTracker.recycle();
mVelocityTracker = null;
}
releaseEdgeEffects();
parent.requestDisallowInterceptTouchEvent(false);//按下时开始让父控件不要处理任何touch事件
break;
}
return true;
}
private void fling(int vY) {
mOverScroller.fling(0, getScrollY(), 0, vY, 0, 0, mMinPosition - mEdgeLength, mMaxPosition + mEdgeLength);
invalidate();
}
//重写滑动方法，设置到边界的时候不滑。滑动完输出刻度
@Override
public void scrollTo(@Px int x, @Px int y) {
if (y < mMinPosition) {
goStartEdgeEffect(y);
y = mMinPosition;
}
if (y > mMaxPosition) {
goEndEdgeEffect(y);
y = mMaxPosition;
}
if (y != getScrollY()) {
super.scrollTo(x, y);
}
mCurrentScale = scrollYtoScale(y);
if (mRulerCallback != null) {
mRulerCallback.onScaleChanging(Math.round(mCurrentScale));
}
}
//头部边缘效果处理
private void goStartEdgeEffect(int y) {
if (mParent.canEdgeEffect()) {
if (!mOverScroller.isFinished()) {
mStartEdgeEffect.onAbsorb((int) mOverScroller.getCurrVelocity());
mOverScroller.abortAnimation();
} else {
mStartEdgeEffect.onPull((float) (mMinPosition - y) / (mEdgeLength) * 3 + 0.3f);
mStartEdgeEffect.setSize(mParent.getCursorWidth(), getHeight());
}
postInvalidateOnAnimation();
}
}
//尾部边缘效果处理
private void goEndEdgeEffect(int y) {
if (mParent.canEdgeEffect()) {
if (!mOverScroller.isFinished()) {
mEndEdgeEffect.onAbsorb((int) mOverScroller.getCurrVelocity());
mOverScroller.abortAnimation();
} else {
mEndEdgeEffect.onPull((float) (y - mMaxPosition) / (mEdgeLength) * 3 + 0.3f);
mEndEdgeEffect.setSize(mParent.getCursorWidth(), getHeight());
}
postInvalidateOnAnimation();
}
}
//取消边缘效果动画
private void releaseEdgeEffects() {
if (mParent.canEdgeEffect()) {
mStartEdgeEffect.onRelease();
mEndEdgeEffect.onRelease();
}
}
//直接跳转到当前刻度
public void goToScale(float scale) {
mCurrentScale = Math.round(scale);
scrollTo(0, scaleToScrollY(mCurrentScale));
// if (mRulerCallback != null) {
// mRulerCallback.onScaleChanging(mCurrentScale);
// }
}
//把滑动偏移量scrollY转化为刻度Scale
private float scrollYtoScale(int scrollY) {
return ((float) (scrollY - mMinPosition) / mLength) * mMaxLength + mParent.getMinScale();
}
//把Scale转化为ScrollY
private int scaleToScrollY(float scale) {
return Math.round((scale - mParent.getMinScale()) / mMaxLength * mLength + mMinPosition);
}
//把Scale转化为ScrollY,放大SCALE_TO_PX_FACTOR倍，以免精度丢失问题
private float scaleToScrollFloatY(float scale) {
return ((scale - mParent.getMinScale()) / mMaxLength * mLength * SCALE_TO_PX_FACTOR + mMinPosition * SCALE_TO_PX_FACTOR);
}
//把移动后光标对准距离最近的刻度，就是回弹到最近刻度
@Override
protected void scrollBackToCurrentScale() {
scrollBackToCurrentScale(Math.round(mCurrentScale));
}
@Override
protected void scrollBackToCurrentScale(int currentIntScale) {
int dy = Math.round((scaleToScrollFloatY(currentIntScale) - SCALE_TO_PX_FACTOR * getScrollY()) / SCALE_TO_PX_FACTOR);
if (dy > minScrollerPx) {
//渐变回弹
mOverScroller.startScroll(getScrollX(), getScrollY(), 0, dy, 500);
invalidate();
} else {
//立刻回弹
scrollBy(0, dy);
}
}
@Override
public void refreshSize() {
mLength = (mParent.getMaxScale() - mParent.getMinScale()) * mParent.getInterval();
mHalfHeight = getHeight() / 2;
mMinPosition = -mHalfHeight;
mMaxPosition = mLength - mHalfHeight;
}
//获取控件宽高，设置相应信息
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
refreshSize();
}
}
