callbacks like shouldComponentUpdate, componentDidUpdate, etc. were getting the full, unsanitized context, instead of the one that's been filtered down to only the fields allowed to be visible by contextTypes.
Context is adding another argument that shifts all of them by one. Since we can already use this.getDOMNode(), it doesn't really make sense to pass it as an argument to that function.
...without preventing clicks on other things.
Just use an `<a name="...">` tag that doesn't take up any space to make sure that we're not covering up something else.
For whatever reason, doing `position: relative; top: -$navHeight;` doesn't work and causes the anchor target not to be moved up. This solution works in both Chrome and Firefox.
When events are captured, the nearest React-rendered ancestor is found and events are propagated to its tree. This causes issues when components are nested as only the innermost component receives the events.
This change modifies this behaviour so events propagate all the way up the DOM hierarchy. To reduce the performance cost, this DOM traversal is only done if the component is actually nested (determined by the `containerIsNested` map which is lazily initialised).
Summary:
adds `this.context` which you can think of as implicit props, which are passed automatically down the //ownership// hierarchy.
Contexts should be used sparingly, since they essentially allow components to communicate with descendants (in the ownership sense, not parenthood sense), which is not usually a good idea. You probably would only use contexts in places where you'd normally use a global, but contexts allow you to override them for certain view subtrees which you can't do with globals.
The context starts out `null`:
var RootComponent = React.createClass({
render: function() {
// this.context === null
}
});
You should **never** mutate the context directly, just like props and state.
You can change the context of your children (the ones you own, not `this.props.children` or via other props) using the new `withContext` method on `React`:
var RootComponent = React.createClass({
render: function() {
// this.context === null
var children = React.withContext({foo: 'a', bar: 'b'}, () => (
// In ChildComponent#render, this.context === {foo: 'a', bar: 'b'}
<ChildComponent />
));
// this.context === null
}
});
Contexts are merged, so a component can override its owner's context **for its children**:
var ChildComponent = React.createClass({
render: function() {
// this.context === {foo: 'a', bar: 'b'} (for the caller above)
var children = React.withContext({foo: 'c'},() => (
// In GrandchildComponent#render,
// this.context === {foo: 'c', bar: 'b'}
<GrandchildComponent />
));
// this.context === {foo: 'a', bar: 'b'}
}
});
Reported on Twitter by AirBnb (who are integrating React into their open-source JS framework). They made a mistake and passed a string in as the
component. We should have a better error message for that.
This renames receiveProps and changes it to take the next component to copy props from instead of just the props. That is,
component.receiveComponent(nextComponent, transaction)
instead of
component.receiveProps(nextComponent.props, transaction)
This is a precursor to adding contexts, which will also need to get propagated just like props. This change allows ReactCompositeComponent to override `receiveProps` and do something like
this._pendingContext = nextComponent.context;