ios - Transparent view is black? -


i'm trying create view transparent in spots see image behind. however, reason in transparent part of view, i'm seeing black, instead of what's behind view. i've trimmed down little code , don't understand why transparent view shows black instead of red (the color of view behind). here's code:

class viewcontroller: uiviewcontroller {      override func viewwillappear(_ animated: bool) {         super.viewwillappear(animated)         let redview = uiview(frame: view.frame)         redview.backgroundcolor = uicolor.red         let transparentview = transparentview(frame: view.frame)          view.addsubview(redview)         view.addsubview(transparentview)     } } 

class transparentview: uiview {      override func draw(_ rect: cgrect) {         uicolor.clear.setfill()         uirectfill(rect) }

i expect screen full red, instead shows full black. before says it's lot easier make clear view, i'm trying more complex things in drawrect, dropped down basic thing try debug problem. missing here?

use self.isopaque = false; make view/layer transparent when drawrect overriden. 

class transparentview: uiview {      override init(frame: cgrect) {         super.init(frame: frame);          self.isopaque = false;  //use this..     }      required init?(coder adecoder: nscoder) {         fatalerror("init(coder:) has not been implemented")     }      override func draw(_ rect: cgrect) {         uicolor.clear.setfill()         uirectfill(rect)     } }

Comments

Post a Comment

Popular posts from this blog

python - Operations inside variables -

this question has answer here: evaluating mathematical expression in string 12 answers i want make python script finds maximum possible output using 2 operations. problem says there syntax error @ 2nd last line, in b in there. how can fix it? x = 0 = int(input("1st number:")) c = int(input("2nd number:" )) e = int(input("3rd number:" )) in range(4): if == 0: b = "+" elif == 1: b = "-" elif == 2: b = "/" else: b = "*" j in range(4): if j == 0: d = "+" elif j == 1: d = "-" elif j == 2: d = "/" else: d = "*" k = b c d e print(k) if you're after variables e on single line, couldn...
Read more

Generic Map Parameter java -

i having lot of methods of type: public static list<eduusers> getdetails(class c, map<string, integer> params) { list<eduusers> details = null; session session = hibernateutil.getsessionfactory().opensession(); transaction tx = null; try { tx = session.begintransaction(); criteria cr = session.createcriteria(c); (map.entry<string, integer> entry : params.entryset()) { cr.add(restrictions.eq(entry.getkey(), entry.getvalue())); } details = cr.list(); tx.commit(); } catch (exception asd) { log.debug(asd.getmessage()); if (tx != null) { tx.commit(); } } { session.close(); } return details; } i trying have generic method them , have written far: public static <t> list<t> getdetails(class<t> c, class<t> b) { l...
Read more

arrays - What causes a java.lang.ArrayIndexOutOfBoundsException and how do I prevent it? -

what arrayindexoutofboundsexception mean , how rid of it? here code sample triggers exception: string[] name = {"tom", "dick", "harry"}; for(int = 0; i<=name.length; i++) { system.out.print(name[i] +'\n'); } your first port of call should documentation explains reasonably clearly: thrown indicate array has been accessed illegal index. index either negative or greater or equal size of array. so example: int[] array = new int[5]; int boom = array[10]; // throws exception as how avoid it... um, don't that. careful array indexes. one problem people run thinking arrays 1-indexed, e.g. int[] array = new int[5]; // ... populate array here ... (int index = 1; index <= array.length; index++) { system.out.println(array[index]); } that miss out first element (index 0) , throw exception when index 5. valid indexes here 0-4 inclusive. correct, idiomatic for statement here be: for (int index = 0; index <...
Read more