When you define a custom element, you supply a prototype object for the element. When any of the element callback functions are called, 'this' always points to the element. If you then call this.methodName from there, 'this' is still the element.
You haven't shown how the functions you wrote are part of a custom element prototype. This is critical info. In particular 'this' in your 'initialize_listeners' may not be the same as 'this' in your 'update_entire_line' method. At the very least you'd need to do update_entire_line.call(this); For some basic info about constructing raw custom elements, see the 'Adding JS properties and methods' section here: http://www.html5rocks.com/en/tutorials/webcomponents/customelements/. Here's some background on the 'this' keyword for reference: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/this . On Tue, Feb 25, 2014 at 5:57 PM, Just.A.Guy <[email protected]> wrote: > I just wrote a "ready" routine for a custom element. > When the "ready" routine is called, "this.shadowRoot" points to the > shadowRoot > and the routine can access the global (polymer-element attributes) values. > > At the end of the "ready" routine a call is made to a routine that appears > above ready-routine. > In that routine it tries to access the global values. In the debugger > they are all undefined. > From what I can tell, the "this" points to new window that does not have > any of the variables > that the ready routine used and created. > > I get an error saying you can not call <xxxx> on undefined. > But if I copy the contents from the routine, to just below the call, and > comment out the call > everything works correctly. > > The sub-function is part of the elements "script" contents but is not a > part of the global options. > I don't want to clutter all of the dependent functions of the element as > global functions. This should not be necessary. > > > here are some snippets of the code: > > --------------------------------------------------------------- > > var update_entire_line = function () > { > my_debug('update_entire_line'); > var lrecl = this.lrecl; > this.lcol.innerHTML = this.lc_text; > this.caret.innerHTML = this.cc_text; > this.rcol.innerHTML = this.rc_text; > }; > > .................... > > var initialize_listeners = function () > { > my_debug('initialize_listners'); > > > var my_doc = this.shadowRoot; > this._root = this.shadowRoot; > var init_text = this.value; > > if ( init_text == null ) > { > init_text = ''; > } > > this.lcol = my_doc.getElementById('left_col'); > this.caret = my_doc.getElementById('caret'); > this.rcol = my_doc.getElementById('right_col'); > > this.caps_lock = false; > this.shift_key = false; > > this.lc_text = this.lcol.innerHTML; > this.cc_text = this.caret.innerHTML; > this.rc_text = init_text; > > this.lc_len = this.lc_text.length > this.cc_len = this.cc_text.length > this.rc_len = this.rc_text.length > console.log('calling initialize_listeners'); > var lrecl = this.lrecl; > > var it_len = init_text.length > if ( it_len < lrecl ) > { > var fill_cnt = lrecl - it_len + 1; > console.log('fill: '+fill_cnt); > this.rc_text = init_text + Array(fill_cnt).join(" "); > this.rc_len = lrecl; > } > > // update_entire_line(); > this.lcol.innerHTML = this.lc_text; > this.caret.innerHTML = this.cc_text; > this.rcol.innerHTML = this.rc_text; > > var ln = my_doc.getElementById('entire_line'); > ln.addEventListener('keydown', key_down, false); > ln.addEventListener('click', mouse_click, false); > > }; > > ------------------------------------------------------------------------------------------ > > > Follow Polymer on Google+: plus.google.com/107187849809354688692 > --- > You received this message because you are subscribed to the Google Groups > "Polymer" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To view this discussion on the web visit > https://groups.google.com/d/msgid/polymer-dev/a977b028-bcd5-492b-9827-e112027725a2%40googlegroups.com > . > For more options, visit https://groups.google.com/groups/opt_out. > Follow Polymer on Google+: plus.google.com/107187849809354688692 --- You received this message because you are subscribed to the Google Groups "Polymer" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To view this discussion on the web visit https://groups.google.com/d/msgid/polymer-dev/CA%2BrMWZjwcV7RQ9O4sBT9R5s2kxxNbKuvXV64mhPN-CVzv1m0GQ%40mail.gmail.com. For more options, visit https://groups.google.com/groups/opt_out.
