MICROSOFT_PRESS_EBOOK_PROGRAMMING_WINDOWS_8_APPS_WITH_HTML_CSS_AND_JAVASCRIPT_PDF

Updating a Remote File: UI
In Scenario 6 (updating a remote file) of the file picker sample, we can see the interactions that take
place when the consuming app writes changes to its local copy, thereby triggering an update to the
remote copy. Start by tapping the Get Save File button in the UI shown next:
In the picker, select the provider sample as the picker source, which invokes the UI of Figure 12-20
through the file save picker contract, implemented through html/fileSavePickerScenario3.html and
js/fileSavePickerScenaro3.js. If you look in the JavaScript file, you’ll again see a call to
setUpdateInformation that’s called when you enter a file name and tap Save. Doing so also returns you
to the picker sample above where Write To File should now be enabled. Tapping Write To File then
reinvokes the provider sample through the cached file updater contract with the UI shown in Figure
12-21. This UI is intended to demonstrate how such a provider app would accommodate overwriting or
renaming the remote file.
FIGURE 12-20 The provider sample’s UI for saving a file; the setUpdateInfomation method is again called on the
provided file to set up the cached file updater relationship.
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