Android layout previewer throws error when adding custom LinearLayout

Question

I've defined a custom ViewGroup that extends the functionality of a LinearLayout:

public class TestLayout extends LinearLayout {

    public TestLayout(Context context, AttributeSet attrs) {
        super(context, attrs);

        LayoutInflater inflater = (LayoutInflater)context.getSystemService
                  (Context.LAYOUT_INFLATER_SERVICE);

        inflater.inflate(R.layout.testlayout, this, true);
    }

}

The layout it inflates (testlayout.xml) looks like this:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" android:gravity="center">

    <Button
        android:id="@+id/button1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="Button"/>

</LinearLayout>

And finally i'm using this custom component in my main.xml:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:orientation="vertical" >

    <my.test.namespace.TestLayout
        android:id="@+id/testLayout1"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content" >
    </my.test.namespace.TestLayout>

</LinearLayout>

When viewing my main.xml in the layout editor, eclipse throws an error: my.test.namespace.TestLayout failed to instantiate.

And the stacktrace:

android.content.res.Resources$NotFoundException: Could not resolve resource value: 0x7F030001.
    at com.android.layoutlib.bridge.android.BridgeResources.throwException(BridgeResources.java:648)
    at com.android.layoutlib.bridge.android.BridgeResources.getLayout(BridgeResources.java:270)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:318)
    at my.test.namespace.TestLayout.<init>(TestLayout.java:18)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at com.android.ide.eclipse.adt.internal.editors.layout.ProjectCallback.instantiateClass(ProjectCallback.java:397)
    at com.android.ide.eclipse.adt.internal.editors.layout.ProjectCallback.loadView(ProjectCallback.java:165)
    at com.android.layoutlib.bridge.android.BridgeInflater.loadCustomView(BridgeInflater.java:205)
    at com.android.layoutlib.bridge.android.BridgeInflater.createViewFromTag(BridgeInflater.java:133)
    at android.view.LayoutInflater.rInflate(LayoutInflater.java:618)
    at android.view.LayoutInflater.inflate(LayoutInflater.java:407)

0x7F030001 points to the layout xml file in R.java. I tried cleaning my project, but that did nothing. Am I using the LayoutInflater wrong, or what is going on here?

Answer 1

The following usually help:

• Clean your project (again, just in case).
• Restart eclipse.
• Refresh your folders in eclipse (right click -> refresh, or select your top folder and press f5).