calculateSelectedX method
calculate the value of x after long pressing and convert to index
Implementation
int calculateSelectedX(double selectX) {
int mSelectedIndex = indexOfTranslateX(xToTranslateX(selectX));
if (mSelectedIndex < mStartIndex) {
mSelectedIndex = mStartIndex;
}
if (mSelectedIndex > mStopIndex) {
mSelectedIndex = mStopIndex;
}
return mSelectedIndex;
}