navBarView.js

(function(ionic) {
'use strict';

  ionic.views.NavBar = ionic.views.View.inherit({
    initialize: function(opts) {
      this.el = opts.el;

      this._titleEl = this.el.querySelector('.title');

      if(opts.hidden) {
        this.hide();
      }
    },
    hide: function() {
      this.el.classList.add('hidden');
    },
    show: function() {
      this.el.classList.remove('hidden');
    },
    shouldGoBack: function() {},

    setTitle: function(title) {
      if(!this._titleEl) {
        return;
      }
      this._titleEl.innerHTML = title;
    },

    showBackButton: function(shouldShow) {
      var _this = this;

      if(!this._currentBackButton) {
        var back = document.createElement('a');
        back.className = 'button back';
        back.innerHTML = 'Back';

        this._currentBackButton = back;
        this._currentBackButton.onclick = function(event) {
          _this.shouldGoBack && _this.shouldGoBack();
        };
      }

      if(shouldShow && !this._currentBackButton.parentNode) {
        // Prepend the back button
        this.el.insertBefore(this._currentBackButton, this.el.firstChild);
      } else if(!shouldShow && this._currentBackButton.parentNode) {
        // Remove the back button if it's there
        this._currentBackButton.parentNode.removeChild(this._currentBackButton);
      }
    }
  });

})(ionic);