Retrieve margins from attributes

Question

I'm trying to get the margins from the .xml file. Currently I'm doing it like so:

mUserDefinedLeftMargin = attrs.getAttributeIntValue("http://schemas.android.com/apk/res/android", "layout_marginLeft", 0);

where attrs is of type AttributeSet (it's received in the constructor or my class which extends RelativeLayout)

The .xml looks like this:

    <ch......MyCustomView
        android:id="@+id/update_progress"
        android:layout_width="400dp"
        android:layout_height="200dp"
        android:layout_marginLeft="10dp"
        android:layout_alignParentRight="true"
        android:visibility="invisible" />

mUserDefinedLeftMargin is still 0 at the end of the above call. Why ?

It is because dp is not int value. Take a look http://stackoverflow.com/questions/8302229/accessing-attrs-in-attributeset-for-custom-components. It is string and you should convert it it to points yourself — Eugen Martynov, Jul 11 '14 at 10:11
excellent ! Please write it as an response, so I can accept it — AndreiBogdan, Jul 11 '14 at 10:14
don't do that, use Context.obtainStyledAttributes(AttributeSet set, int[] attrs) instead, no need for converting a String like "14.0sp" to float value — pskink, Jul 11 '14 at 10:18
@EugenMartynov just use TypedArray.getDimension*() to get the float value — pskink, Jul 11 '14 at 10:37

score 1 · Accepted Answer · answered Jul 11 '14 at 10:21

1

It is because dp is not int value. You should first get it as text:

String dpSizeText = attrs.getAttributeValue("http://schemas.android.com/apk/res/android", "layout_marginLeft");

And convert it to pixels after:

int dpSizeInt = Integer.parseInt(dpSizeText.substring(0, dpSizeText.indexOf("dp")));
Resources r = getResources();
float px = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP, dpSizeInt, r.getDisplayMetrics());

answered Jul 11 '14 at 10:21

Eugen Martynov

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@AndreiBogdan please don't do that, use Context.obtainStyledAttributes(AttributeSet set, int[] attrs) instead – pskink Jul 11 '14 at 10:42

Retrieve margins from attributes

1 Answers1