MICROSOFT_PRESS_EBOOK_PROGRAMMING_WINDOWS_8_APPS_WITH_HTML_CSS_AND_JAVASCRIPT_PDF

Again, refer to the documentation on Windows.UI.Input.GestureRecognizer for all the details and
refer to the sample for some bits of code. As one extra example, here’s a snippet to capture a small
horizontal motion using the manipuationTranslateX setting:
var recognizer = new Windows.UI.Input.GestureRecognizer();
recognizer.gestureSettings = Windows.UI.Input.GestureSettings.manipulationTranslateX;
var DELTA = 10;
myElement.addEventListener('MSPointerDown', function (e) {
recognizer.processDownEvent(e.getCurrentPoint(e.pointerId));
});
myElement.addEventListener('MSPointerUp', function (e) {
recognizer.processUpEvent(e.getCurrentPoint(e.pointerId));
});
myElement.addEventListener('MSPointerMove', function (e) {
recognizer.processMoveEvents(e.getIntermediatePoints(e.pointerId));
});
// Remember removeEventListener as needed for this event
recognizer.addEventListener('manipulationcompleted', function (args) {
var pt = args.cumulative.translation;
if (pt.x < -DELTA) {
// move right
}
else if (pt.x > DELTA) {
// move left
}
});
Beyond the recognizer, do note that you can always go the low-level route and do your own
processing of MSPointer* events however you want, completely bypassing the gesture recognizer. This
would be necessary if the configurations allowed by the recognizer object don’t accommodate your
specific need. At the same time, now is a good opportunity to re-read “Sidebar: Creating Completely
New Gesture?” at the end of the earlier section on the touch language. It addresses a few of the
questions about when and if custom gestures are really needed.
Keyboard Input and the Soft Keyboard
After everything to do with touch and other forms of input, it seems almost anticlimactic to consider the
humble keyboard. Yet of course the keyboard remains utterly important for textual input, whether it’s a
physical key-board or the on-screen “soft” keyboard. It is especially important for accessibility as well, as
some users are physically unable to use a mouse or other devices. In fact, the Windows 8 app
certification requirements (section 3.5) make keyboard input mandatory.
Fortunately, there is nothing special about handling keyboard input in a Windows Store app, but a
little goes a long way. Drawing from Implementing keyboard accessibility, here’s a summary:
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