How to detect model parameter change event in mith

2019-02-26 18:20发布

问题:

I recently started learning mithril.js and I'm wondering how can I make very basic Model -> View one way data binding app.

TestModel = function(data){
  this.name = m.prop(data.name)
}
testModel = new TestModel({name: "John"})

code above declare a model and it works perfectly as getter/setter. but how can I set an event listener for the model event like Backbone's listenTo('model',"change",callbackFunc)?

all sample codes I saw are setting events for actual user actions like click,keyup or onchange.but never listen to actual model value's state directly.

am I missing something or am I understanding how to use mithril.js wrongly?

thanks in advance.

回答1:

One of the key ideas with Mithril is that changes usually happens after an event:

  • A user action like onclick or keyup defined in a m() view template
  • An ajax request made with m.request

Mithril automatically redraws after those, alleviating the need for most listeners.

If you are updating your models through some other method and you need to redraw manually, use m.redraw or m.startComputation / m.endComputation. Thanks to Mithril's DOM diff algorithm, redraws are very cheap so don't be afraid to use them (with some common sense, of course!) Check out the m.redraw documentation for more info.