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XML parsing error: unbound prefix on custom LinearLayout

I found this example of a Custom LinearLayout on https://stackoverflow.com/a/3776321/2121 , but it throws errors when I try to run it, can someone find out what's wrong with it?

Custom LinearLayout:

package com.example.androidapp.widgets;

import android.content.Context;
import android.content.res.TypedArray;
import android.util.AttributeSet;
import android.view.View;
import android.view.animation.Animation;
import android.view.animation.Transformation;
import android.widget.LinearLayout;

public class ExpandablePanel extends LinearLayout {

    private final int mHandleId;
    private final int mContentId;

    private View mHandle;
    private View mContent;

    private boolean mExpanded = true;
    private int mCollapsedHeight = 0;
    private int mContentHeight = 0;

    public ExpandablePanel(Context context) {
        this(context, null);
    }

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

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

        // How high the content should be in "collapsed" state
        mCollapsedHeight = (int) a.getDimension(
            R.styleable.ExpandablePanel_collapsedHeight, 0.0f);

        int handleId = a.getResourceId(R.styleable.ExpandablePanel_handle, 0);
        if (handleId == 0) {
            throw new IllegalArgumentException(
                "The handle attribute is required and must refer "
                    + "to a valid child.");
        }

        int contentId = a.getResourceId(R.styleable.ExpandablePanel_content, 0);
        if (contentId == 0) {
            throw new IllegalArgumentException(
                "The content attribute is required and must refer "
                    + "to a valid child.");
        }

        mHandleId = handleId;
        mContentId = contentId;

        a.recycle();
    }

    @Override
    protected void onFinishInflate() {
        super.onFinishInflate();

        mHandle = findViewById(mHandleId);
        if (mHandle == null) {
            throw new IllegalArgumentException(
                "The handle attribute is must refer to an"
                    + " existing child.");
        }

        mContent = findViewById(mContentId);
        if (mContent == null) {
            throw new IllegalArgumentException(
                "The content attribute is must refer to an"
                    + " existing child.");
        }

        mHandle.setOnClickListener(new PanelToggler());
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        if (mContentHeight == 0) {
            // First, measure how high content wants to be
            mContent.measure(widthMeasureSpec, MeasureSpec.UNSPECIFIED);
            mContentHeight = mContent.getMeasuredHeight();
        }

        // Then let the usual thing happen
        super.onMeasure(widthMeasureSpec, heightMeasureSpec);
    }

    private class PanelToggler implements OnClickListener {
        @Override
        public void onClick(View v) {
            Animation a;
            if (mExpanded) {
                a = new ExpandAnimation(mContentHeight, mCollapsedHeight);
            } else {
                a = new ExpandAnimation(mCollapsedHeight, mContentHeight);
            }
            a.setDuration(500);
            mContent.startAnimation(a);
            mExpanded = !mExpanded;
        }
    }

    private class ExpandAnimation extends Animation {
        private final int mStartHeight;
        private final int mDeltaHeight;

        public ExpandAnimation(int startHeight, int endHeight) {
            mStartHeight = startHeight;
            mDeltaHeight = endHeight - startHeight;
        }

        @Override
        protected void applyTransformation(float interpolatedTime,
            Transformation t) {
            android.view.ViewGroup.LayoutParams lp = mContent.getLayoutParams();
            lp.height = (int) (mStartHeight + mDeltaHeight * interpolatedTime);
            mContent.setLayoutParams(lp);
        }

        @Override
        public boolean willChangeBounds() {
            // TODO Auto-generated method stub
            return true;
        }
    }
}

res> values> attrs.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
  <declare-styleable name="ExpandablePanel">
    <attr name="handle" format="reference" />
    <attr name="content" format="reference" />
    <attr name="collapsedHeight" format="dimension" />
  </declare-styleable>
</resources>

main.xml:

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

<com.example.androidapp.widgets.ExpandablePanel
    android:orientation="vertical"
    android:layout_height="wrap_content"
    android:layout_width="fill_parent"
    cl:handle="@+id/expand"
    cl:content="@+id/value"
    cl:collapsedHeight="50dip">
    <TextView
        android:id="@id/value"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:maxHeight="50dip"
        />
    <Button
        android:id="@id/expand"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="More" />
</com.example.androidapp.widgets.ExpandablePanel>


</LinearLayout>

Action class:

package com.example.androidapp.widgets;

import android.app.Activity;
import android.os.Bundle;

public class GoodPanelsActivity extends Activity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.main);
    }
}

LogCat Error:

FATAL EXCEPTION: main java.lang.RuntimeException: cannot start Events ComponentInfo {com.example.androidapp.widgets / com.example.androidapp.widgets.GoodPanelsActivity}: android.view.InflateException: binary line of XML file # 9: Error ballooning class com.example.androidapp.widgets.ExpandablePanel

EDIT: more from LogCat

java.lang.reflect.InvocationTargetException java.lang.reflect.Constructor.constructNative( ) java.lang.reflect.Constructor.newInstance(Constructor.java:415) android.view.LayoutInflater.createView(LayoutInflater.java:505) by: java.lang.IllegalArgumentException: handle . com.example.androidapp.widgets.ExpandablePanel. (ExpandablePanel.java:39)

+5
3

- :

main.xml:

xmlns:cl="http://schemas.android.com/apk/lib/com.example.androidapp.widgets"

:

xmlns:cl="http://schemas.android.com/apk/res/com.example.androidapp.widgets"

, ExpandablePanel res.

.

+6

, com.example.androidapp.widgets.ExpandablePanel buildpath. , , .

, LibraryProject, Project->Properties->Android Library .

Project, Properties->Java Build Path->Projects .

0

script, Android, .

, main.xml.

ExpendablePanel, , :

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

<com.martin.myapp.widgets.ExpandablePanel
    android:orientation="vertical"
    android:layout_height="wrap_content"
    android:layout_width="fill_parent"
    cl:handle="@+id/expand"
    cl:content="@+id/value"
    cl:collapsedHeight="50dip">
    <TextView
        android:id="@id/value"
        android:layout_width="fill_parent"
        android:layout_height="wrap_content"
        android:maxHeight="50dip"
        />
    <Button
        android:id="@id/expand"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:text="More" />
</com.martin.myapp.widgets.ExpandablePanel>

, .

I made ExpandablePanel.java and copied a script that extends LinearLayout there, does not give me any errors. My attrs.xml is also error free.

Eclipse does not give me errors on startup. It starts up and sends it to my phone. What is where the force closes. When I remove the ExpandablePanel layout in main.xml, it launches and is an empty application.

I really can't understand.

-1
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