android - Appwidget size calculation

Question

It might be me, but when I calculate minimum app widget sizes according to the formula given on the android page I don't get the right widget widths; The formula is as follows:

width(n) = (70 x n) - 30

When I want to have a 5x1 widget, the correct width would be (5 * 70) - 30 = 320dp. However when testing this on a motorola Xoom it resolves to being a 4x1 widget. I've tested different values and 400dp seems good for 5x1 on the motorola xoom with Honeycomb, but then I'd test it on a regular Galaxy Tab with Gingerbread and then it resolves to a 6x1 (like one would expect).

So two questions here;

• What difference between Gingerbread and Honeycomb am I overlooking?
• Since I know ICS widget size no longer has padding between widgets, is there some rule of thumb here as well?

Answer 1

In my 4x1 widget, I used these dimensions for res/values/dimens.xml:

<!-- size = (74 x n) - 2 -->
<dimen name="appwidget_margin">0dp</dimen>
<dimen name="appwidget_min_width">294dp</dimen>
<dimen name="appwidget_min_height">72dp</dimen>

and for res/values-v14/dimens.xml:

<!-- size = (70 x n) - 30 -->
<dimen name="appwidget_margin">0dp</dimen>
<dimen name="appwidget_min_width">250dp</dimen>
<dimen name="appwidget_min_height">40dp</dimen>

I used widget templates pack for background images .

In official guide there is written that default margin in res/values/dimens.xml should be 8dp, but if I use 8dp, my widget is smaller than standard widgets on the desktop (google search, weather etc.). Thats's because margin for v1-v13 is built in the background image:

I tested it on HTC Desire, Nexus S, emulator Android 2.2 and emulator Android 2.3.3. With the templates pack backgrounds and configuration above, my widget's size is the same as other standard widgets and looks good on all devices I tested.

There is also problem with various launchers. I recommend this article to read: http://radleymarx.com/blog/app-widget-padding-margins-in-ics-android/