Sencha Touch 2 read values from key AND value from nested JSON - json

Question

I am trying to load some JSON, in which I store a lot of variables about some 100 anaesthetic drugs for pediatric patients.
The actual values get calculated before from patient's weight, age etc.:
Example:
var propofolInductionTitle = propofolName + ' ' + propofol0PercentConcentration + '- Induktion';
var propofol0InductionDosageMG = (Math.round(kg * 2 * 10) / 10) + ' - ' + (Math.round(kg * 5 * 10) / 10);
I then create my drug as a block of json consisting of the variables I need which are later to be replaced by the calculated values. I specifically try to avoid Strings in the JSON to allow for easier localization to english and french when all variables are defined in the math block.
var hypnotikaJSON = {
"thiopentalTitle": [
{"thiopentalBrandName": ""},
{"vialContentTitle": "thiopentalVialContent"},
{"solutionTitle": "thiopentalSolution"},
{"concentrationTitle": "thiopentalConcentration"},
{"dosageString": "thiopentalDosageString"},
{"atWeight": "thiopentalDosageMG"},
{"thiopentalAtConcentration": "thiopentalDosageML"}
],
"propofolInductionTitle": [
{"propofolInductionBrandName": ""},
{"propofolVialContentTitle": "propofolInductionVialContent"},
{"propofolSolutionTitle": "propofolSolution"},
{"propofolConcentrationTitle": "propofolInductionConcentration"},
{"propofolInductionDosageStringTitle": "propofolInductionDosageString"},
{"atWeight": "propofolInductionDosageMG"},
{"propofolAtInductionConcentration": "propofolInductionDosageML"}
],
"propofolSedationTitle": [
{"propofolSedationBrandName":""},
{"propofolVialContentTitle":"propofolSedationVialContent"},
{"propofolSolutionTitle":"propofolSolution"},
{"propofolConcentrationTitle":"propofolSedationConcentration"},
{"propofolSedationDosageStringTitle":"propofolSedationDosageString"},
{"atWeight":"propofolSedationDosageMG"},
{"propofolAtSedationConcentration":"propofolSedationDosageML"}
],
"laryngealMaskTitle": [
{"laryngealMaskSizeTitle":"laryngealMaskSize"},
{"laryngealMaskCuffSizeTitle":"laryngealMaskCuffSize"},
{"laryngealMaskBiggestETTTitle":"laryngealMaskBiggestETT"},
{"laryngealMaskBronchoscopeSizeTitle":"laryngealMaskBronchoscopeSize"}
]
};
My specific need is that the JSON reader has to give me the key AND value of each object as I need both to populate a template. The reason ist that the fields for the drugs are different in parts. Some have additional routes of administration so I have another key:value pair a different drug doesnt have. Some are given both as bolus and per drip, some arent. So no convenient json structure ist possible.
I found an answer by rdougan here that partly allowed me to do just that:
Model:
Ext.define('my.model.Drug', {
extend: 'Ext.data.Model',
config: {
fields: ['name', 'value']
}
});
Custom Json Reader:
Ext.define('Ext.data.reader.Custom', {
extend: 'Ext.data.reader.Json',
alias: 'reader.custom',
getRoot: function (data) {
if (this.rootAccessor) {
data = this.rootAccessor.call(this, data);
}
var values = [],
name;
for (name in data) {
values.push({
name: name,
value: data[name]
});
}
return values;
}
});
Store:
var store = Ext.create('Ext.data.Store', {
fields: ['name', 'value'],
data: hypnotikaJSON,
autoLoad: true,
proxy: {
type: 'memory',
reader: {
type: 'custom'
}
}
});
Panel:
this.viewport = new Ext.Panel({
fullscreen: true,
layout: 'fit',
items: [{
xtype: 'list',
itemTpl: '<p class="description">{name}</p><p class ="values">{value}</p>',
store: store
}]
});
Unfortunately I'm a physician and no programmer, and after a lot of reading I cant find out to apply this to a nested JSON. The custom reader seems to only go for the first level.
I could do it without a reader, without a store with just a lot of plan html around each entry, that has proven to be very very slow though so I would like to avoid it while updating from Sencha Touch 1.1. and better do it right this time.
Could you please point me to a way to parse this ugly data structure?
Thank you

Answer 1

I don't know much about extending JSON readers, so just guessing, but maybe you are supposed override the 'read' method? Then you can go over the JSON as you wish
Also, if you have control over the JSON you should consider changing it.
Usually, the keys in JSON should be the same throughout all items in the array.
keys are not data, they are metadata.
So, if you do have different properties between different drugs, then something like this might be a solution:
[{
name: 'Propofol 1%',
properties: [
{title: 'induction', value: '22-56g'},
{title: 'Sedation', value: '22'},
etc.
]},
{name: 'nextDrug'}
etc..