Passing id of adjacent view in xml to the custom view and retrieving it in constructor of custom view

Question

Below is my xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:padding="5dp" xmlns:app="http://schemas.android.com/apk/res/com.infibeam.allthingsd.apps.spinr">

   <com.asyncimagewidget.AsyncImageView
        android:id="@+id/discover_list_icon"
        android:layout_width="130dp"
        android:layout_height="130dp"
        android:layout_alignParentLeft="true"
        android:layout_centerHorizontal="true"
        app:progressId="@+id/asyncLoadingProgress"
         />
    <ProgressBar
        android:id="@+id/asyncLoadingProgress"
        android:layout_width="130dp"
        android:layout_height="130dp"
        android:layout_alignParentLeft="true"
        android:layout_centerHorizontal="true"
     />
</RelativeLayout>

You can see

app:progressId="@+id/asyncLoadingProgress"

Which is a custom attribute I had defined in the attrs.xml which is as follows.

<resources>
    <declare-styleable name="AsyncImageView">
        <attr name="defaultSrc" format="reference" />
        <attr name="parentId" format="reference" />
        <attr name="progressId" format="reference" />
        <attr name="url" format="string" />
        <attr name="inDensity">
            <enum name="ldpi" value="120" />
            <enum name="mdpi" value="160" />
            <enum name="hdpi" value="240" />
            <enum name="xhdpi" value="320" />
        </attr>
    </declare-styleable>
</resources>

Now My question is I want to obtain the resource identifier of Progressbar in constructor of AsyncImageView which is as follows.

public AsyncImageView(Context context, AttributeSet attrs, int defStyle) {
        super(context, attrs, defStyle);

        initializeDefaultValues();

        TypedArray a = context.obtainStyledAttributes(attrs,
                R.styleable.AsyncImageView, defStyle, 0);

        Drawable d = a.getDrawable(R.styleable.AsyncImageView_defaultSrc);
        if (d != null) {
            setDefaultImageDrawable(d);
        }

        final int inDensity = a
                .getInt(R.styleable.AsyncImageView_inDensity, -1);
        if (inDensity != -1) {
            setInDensity(inDensity);
        }

        setUrl(a.getString(R.styleable.AsyncImageView_url));

        a.recycle();

    }

Answer 1

Now My question is I want to obtain the resource identifier of Progressbar in constructor of AsyncImageView which is as follows.

If I'm not mistaken you can use the getResourceId() method in your constructor:

TypedArray a = context.obtainStyledAttributes(attrs, R.styleable.AsyncImageView, defStyle, 0);
int progressId = a.getResourceId(R.styleable.AsyncImageView_progressId, 0);

Also, if you declare the id of the ProgressBar in the AsyncImageView attribute then I think you need set the id like this for the ProgressBar:

android:id="@id/asyncLoadingProgress"