@Override
public void draw(@NonNull Canvas canvas) {
super.draw(canvas);
if (leftGlow != null) {
final int scrollX = getScrollX();
if (!leftGlow.isFinished()) {
final int restoreCount = canvas.save();
final int height = getHeight() - getPaddingTop() - getPaddingBottom();
canvas.rotate(270);
canvas.translate(-height + getPaddingTop(), Math.min(0, scrollX));
leftGlow.setSize(height, getWidth());
if (leftGlow.draw(canvas)) {
postInvalidate();
}
canvas.restoreToCount(restoreCount);
}
if (!rightGlow.isFinished()) {
final int restoreCount = canvas.save();
final int width = getWidth();
final int height = getHeight() - getPaddingTop() - getPaddingBottom();
canvas.rotate(90);
canvas.translate(-getPaddingTop(), -(Math.max(getScrollRange(), scrollX) + width));
rightGlow.setSize(height, width);
if (rightGlow.draw(canvas)) {
postInvalidate();
}
canvas.restoreToCount(restoreCount);
}
}
}
@Override
public boolean dispatchTouchEvent(@NonNull MotionEvent ev) {
switch (ev.getAction()) {
case MotionEvent.ACTION_MOVE:
float deltaX = prevX - ev.getX();
if (!drag && Math.abs(deltaX) > mTouchSlop) {
final ViewParent parent = getParent();
if (parent != null) {
parent.requestDisallowInterceptTouchEvent(true);
}
drag = true;
if (deltaX > 0) {
deltaX -= mTouchSlop;
} else {
deltaX += mTouchSlop;
}
}
if (drag) {
final int oldX = getScrollX();
final int range = getScrollRange();
boolean canOverscroll =
overscrollMode == OVER_SCROLL_ALWAYS
|| (overscrollMode == OVER_SCROLL_IF_CONTENT_SCROLLS && range > 0);
if (canOverscroll) {
float pulledToY = oldX + deltaX;
if (pulledToY < 0) {
leftGlow.onPull(deltaX / getWidth(), 1.f - ev.getY() / getHeight());
if (!rightGlow.isFinished()) rightGlow.onRelease();
} else if (pulledToY > range) {
rightGlow.onPull(deltaX / getWidth(), ev.getY() / getHeight());
if (!leftGlow.isFinished()) leftGlow.onRelease();
}
if (leftGlow != null && (!leftGlow.isFinished() || !rightGlow.isFinished()))
postInvalidate();
}
}
break;
case MotionEvent.ACTION_UP:
case MotionEvent.ACTION_CANCEL:
if (drag) {
drag = false;
if (leftGlow != null) {
leftGlow.onRelease();
rightGlow.onRelease();
}
}
break;
}
prevX = ev.getX();
return super.dispatchTouchEvent(ev);
}