2-way-object-databinding

问题 What is the simplest way to create data bindings to attributes, in Polymer, when working with innerHTML? This is an example of what i mean - http://jsfiddle.net/ry6og1q9/2/ <paper-input inputValue="{{foo}}" label="static foo"></paper-input> "staticFoo" paper-input is data bound to with {{foo}} - a two way data binding. var c = this.$.dynamicFooPlaceHolder; c.innerHTML = ''; var e = document.createElement('div'); e.innerHTML = '<paper-input id="dynamicFoo" inputValue="{{foo}}" label="dynamic

问题 I have used Data binding in my existing code and now I am migrating to Room for persistence. I have followed the steps mentioned in Florina's Blog for room My Code builds fine without java code error or BR related error when I remove room dependency annotationProcessor 'android.arch.persistence.room:compiler:1.0.0' and its runs too, but gives Runtime exception saying database_Impl does not exists. As it couldn't generate that's file. But after I put Annotation processor back, it give me Error

问题 I know Angular2 doesn't have two-way data binding but is there a way to mimick the two-way data binding behavior from Angular1.x? 回答1: Note - scroll down the answer for ng-model binding You could actually do that, just that you need to invoke internal changelistener tick (similar to digest) to update binding in the zone, You can just add a (keyup) event for that. Similarly you could use directive bindings as well with properties dictionary of component settings. Example:- <input #label (keyup

问题 In AngularJs if you had 2 lists and the second list depended on the values of the first list, it would automatically update. This could be done simply like this: function toDoCtrl($scope) { $scope.questions = [ { active: true, text: "Question 1", answers: [ { text: "Answer 1" }, { text: "Answer 1" }, { text: "Answer 3" } ] }, { active: true, text: "Question 2", answers: [ { text: "Answer 4" }, { text: "Answer 5" }, { text: "Answer 6" } ] } ]; $scope.setActive = function(question) { question

问题 I would like to bind a property (flag_baz in this case) from a JSONModel to a checkbox. Thing is that the json model looks like this. { foo: "Foo", bar:"Bar", flag_baz : "X" } in this case X means "true" and an empty string means "false" What i would like to do is evaluate a function for binding from model to the checkbox (that would translate "X"/"" to true/false) and evaluate some other function when binding from the checkbox to the model (that would translate from true/false back to "X"/""

问题 Given DoubleProperty A; DoubleProperty minusA; is there a way to bind their negations bidirectionally to each other, so that A.get() == -minusA.get() at all times, and both can be set() ? 回答1: I tried but did´t find a way by using a bidirectional binding but maybe you could use an InvalidationListner on both? Something like A.addListener((Observable observable) -> { System.out.println("A is invalid"); minusA.set(A.get() *-1); }); minusA.addListener((Observable observable) -> { System.out

问题 I create these methods for custom data binding @BindingAdapter("android:text") public static void setShortText(TextView view, short value) { view.setText(String.valueOf(value)); } @InverseBindingAdapter(attribute = "android:text") public static Short getShortText(TextView view) { try { return Short.parseShort(view.getText().toString()); } catch (NumberFormatException e) { return null; } } @BindingAdapter("android:text") public static void setIntText(TextView view, int value) { view.setText

问题 The one-way databind Eval function belongs to DataBinder class and can be accessed in a page through TemplateControl.Eval method that calls the DataBinder.Eval method using the GetDataItem method to resolve the object reference that the expression is evaluated against, phew! OK... so, how the two-way databind Bind function works? It belongs to which class? 回答1: As far as I could tell the "Bind" is not a method but rather a language construct. Source and further reading: http://weblogs.asp.net

问题 Hi hope someone can advise what I am missing. In my plunker demo I have an edit button that on clicking gives a static id of 2 right now. (this simulates an id parameter coming into this component in my real project) What I am trying to do is take the passed in id and find the user and select them in the dropdownlist so it then populates my other fields, like it currently does if you just select a user from the select list. In my code I can see I have the id and can find the full name that

问题 project/build.gradle buildscript { repositories { maven { url 'https://maven.fabric.io/public' } google() jcenter() } dependencies { classpath 'com.android.tools.build:gradle:3.5.0' classpath 'com.google.gms:google-services:4.0.1' // NOTE: Do not place your application dependencies here; they belong // in the individual module build.gradle files } } allprojects { repositories { mavenCentral() maven { url 'https://maven.google.com' } maven { url 'https://jitpack.io' } google() jcenter() } }