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pxt-microbit Accessibility PR (#529)

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* Accessibility changes
This commit is contained in:
Sam El-Husseini
2017-09-07 13:42:08 -07:00
committed by GitHub
parent 3f87576a50
commit e3975e65e5
357 changed files with 1641 additions and 3540 deletions
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10
docs/reference/event-handler.md
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@@ -4,7 +4,7 @@ Event handlers - how they work.
An event handler is code that is associated with a particular event, such as "button A pressed". You create (or register) the association between an event and an event handler by calling a function named "on <event>". After registering an event handler with an event, then whenever that event occurs, the event handler code executes.
### Registering an event handler
## Registering an event handler
Functions named "on <event>" create an association between an event and the event handler code. For example, the following code registers the event handler (the code between the `do` and `end` keywords) with the event of a press of button A:
@@ -16,7 +16,7 @@ input.onButtonPressed(Button.A, () => {
After this code executes, then whenever button A is pressed in the future, the string "hello" will be printed.
### Event handlers are active for the entire program execution
## Event handlers are active for the entire program execution
Once you have registered an event handler for an event, like above, that event handler is active for the rest of the program execution. If you want to stop the string "hello" from printing each time button A is pressed then you need to arrange for the following code to execute:
@@ -27,7 +27,7 @@ input.onButtonPressed(Button.A, () => {
The above code associated an event handler that does nothing with the event of a press of button A.
### There is only one event handler per event
## There is only one event handler per event
The above example also illustrates that there is only one event handler for each event. What is the result of the following code?
@@ -49,11 +49,11 @@ input.onButtonPressed(Button.A, () => {
})
```
### To learn more
## To learn more
To learn more about how the @boardname@ queues up and schedules event handlers, see [the @boardname@ - a reactive system](/device/reactive)
### see also
## see also
[on button pressed](/reference/input/on-button-pressed), [on pin up](/reference/input/on-pin-pressed), [on shake](/reference/input/on-gesture)