Android Market的 Loading效果

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:gravity="center_vertical|center_horizontal"
    android:orientation="horizontal"
    android:id="@+id/fullscreen_loading_indicator"
    android:visibility="gone"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
    <ProgressBar
        android:layout_gravity="center_vertical"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        style="?android:attr/progressBarStyleSmall"
        >
    </ProgressBar>
    <TextView
        android:id="@+id/current_action"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_marginLeft="5.0dip"
        android:text="@string/loading"
        >
    </TextView>
</LinearLayout>

<?xml version="1.0" encoding="utf-8"?>
<FrameLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
    <LinearLayout
        android:orientation="vertical"
        android:id="@+id/main_info"
        android:visibility="gone"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        >
    </LinearLayout>
    <include
        android:visibility="visible"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        layout="@layout/fullscreen_loading_indicator"
        >
    </include>
</FrameLayout>

package org.lytsing.android.loading;

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

public class Loading extends Activity {

    private LinearLayout mLoadingLayout;

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

        // TODO: dismiss the loading, use this snippet code.
        //mLoadingLayout = (LinearLayout)findViewById(R.id.fullscreen_loading_indicator);
        //mLoadingLayout.setVisibility(View.GONE);
    }
}