Custom Android control with children

I'm trying to create a custom Android control that contains a LinearLayout. You can think of it as an extended LinearLayout with fancy borders, a background, an image on the left...

I could do it all in XML (works great) but since I have dozens of occurences in my app it's getting hard to maintain. I thought it would be nicer to have something like this:

/* Main.xml */
<MyFancyLayout>
    <TextView />   /* what goes inside my control's linear layout */
</MyfancyLayout>

How would you approach this? I'd like to avoid re-writing the whole linear layout onMeasure / onLayout methods. This is what I have for the moment:

/* MyFancyLayout.xml */
<TableLayout>
    <ImageView />
    <LinearLayout id="container" />   /* where I want the real content to go */
</TableLayout>

and

/* MyFancyLayout.java */
public class MyFancyLayout extends LinearLayout
{
    public MyFancyLayout(Context context) {
        super(context);
        View.inflate(context, R.layout.my_fancy_layout, this);
    }
}

How would you go about inserting the user-specified content (the TextView in main.xml) in the right place (id=container)?

Cheers!

Romain

----- edit -------

Still no luck on this, so I changed my design to use a simpler layout and decided to live with a bit of repeated XML. Still very interested in anyone knows how to do this though!

android border android-linearlayout

Edit Report

This approach saves me a lot of code! :)

As esteewhy explains, just swap the xml-defined contents into where you want them internally in your own layout, in onFinishInflate(). Example:

I take the contents that I specify in the xml:

<se.jog.custom.ui.Badge ... >
    <ImageView ... />
    <TextView ... />
</se.jog.custom.ui.Badge>

... and move them to my internal LinearLayout called contents where I want them to be:

public class Badge extends LinearLayout {
    //...
    private LinearLayout badge;
    private LinearLayout contents;

    // This way children can be added from xml.
    @Override
    protected void onFinishInflate() {      
        View[] children = detachChildren(); // gets and removes children from parent
        //...
        badge = (LinearLayout) layoutInflater.inflate(R.layout.badge, this);
        contents = (LinearLayout) badge.findViewById(R.id.badge_contents);
        for (int i = 0; i < children.length; i++)
            addView(children[i]); //overridden, se below.
        //...
        super.onFinishInflate();
    }

    // This way children can be added from other code as well.
    @Override
    public void addView(View child) {
        contents.addView(child);
}

Combined with custom XML attributes things gets very maintainable.

answered 2011-05-18T09:45:46.800

Custom Android control with children

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