I find some code about getting position from UITextView, but the guy didn't
give the full code, I fill up the missing code(the "while loop"), now I can get the position
in text view, but this is my first version of this method, might have some bugs.
-(CGPoint)getPositionInTextView:(UITextView*) textView{
CGPoint origin = textView.frame.origin;
NSString* head = [textView.text substringToIndex:textView.selectedRange.location];
CGSize initialSize = [head sizeWithFont:textView.font constrainedToSize:textView.contentSize lineBreakMode:UILineBreakModeWordWrap];
NSUInteger startOfLine = [head length];
while (startOfLine > 0) {
startOfLine--;
NSString* reduction=[head substringToIndex:startOfLine];
CGSize reductionSize = [reduction sizeWithFont:textView.font constrainedToSize:textView.contentSize lineBreakMode:UILineBreakModeWordWrap];
if(reductionSize.height<initialSize.height)
break;
}
NSString* tail = [head substringFromIndex:startOfLine];
CGSize lineSize = [tail sizeWithFont:textView.font forWidth:textView.contentSize.width lineBreakMode:UILineBreakModeWordWrap];
CGPoint cursor = origin;
cursor.x += lineSize.width;
cursor.y += initialSize.height - lineSize.height;
return cursor;
}
