[Schol-R-LEA]

Note: This was posted earlier at Android Central, under the mistaken impression that it was primarily a development forum. If there are any relevant replies at that site, I will re-post them here.

I am developing an app which (at its current stage of development) consists of a login Activity, which leads to a TabActivity containing four tabs, each of which is instantiated as a separate Activity. I need to be able to pass the user information (or at least the user ID) to some but not all of the tabbed Activities. I am able to pass the data from the login screen to the TabActivity (this has been confirmed by stepping through the relevant section of code), but my attempts to use a similar approach to pass a Bundle to the sub-Activities does not actually pass the Bundle to the child Activities. The relevant code for the TabActivity and an example child Activity is as follows:

ParentTabActivity.java:

package com.allpropestservices.bugpromobile;

import android.app.TabActivity;
import android.content.Intent;
import android.content.res.Resources;
import android.os.Bundle;
import android.util.Log;
import android.widget.TabHost;


public class ParentTabActivity extends TabActivity {
	public static final String TAG = "ParentTabActivity";
	public Long userId;
	
	@Override
	public void onCreate(Bundle savedInstanceState) {
	    super.onCreate(savedInstanceState);
	    setContentView(R.layout.parent);
	    
	    Bundle b = getIntent().getExtras();
	    
	    try {
	    	userId = b.getLong("UserId");
	    }
	    catch (RuntimeException e) {
	    	String err = e.toString() + " in " + TAG + ".onCreate()";
			Log.v(TAG, err);
	    }
	    
	    Resources res = getResources();  // Resource object to get Drawables
	    TabHost tabHost = getTabHost();  // The activity TabHost
	    TabHost.TabSpec spec;            // Reusable TabSpec for each tab
	    Intent intent;                   // Reusable Intent for each tab
	    Bundle userData;
	    
	    
	    // Create an Intent to launch an Activity for the tab (to be reused)
	    intent = new Intent().setClass(this, AnnouncementActivity.class);
	    // prepare a Bundle to pass to each of the sub-activities
	    userData = new Bundle();
    	userData.putLong("UserID", userId);
    	intent.putExtras(userData);
	    // Initialize a TabSpec for each tab and add it to the TabHost
	    spec = tabHost.newTabSpec("Announcements").setIndicator("Announcements",
	    		res.getDrawable(R.drawable.ic_menu_notifications))
	    		.setContent(intent);
	    tabHost.addTab(spec);

	    intent = new Intent().setClass(this, AlertActivity.class);
	    userData = new Bundle();
    	userData.putLong("UserID", userId);
	    intent.putExtras(userData);
	    spec = tabHost.newTabSpec("Alerts").setIndicator("Alerts",
	    		res.getDrawable(R.drawable.ic_menu_inbox)) 
	            .setContent(intent);
	    tabHost.addTab(spec);

	    intent = new Intent().setClass(this, TimeClockActivity.class);
	    userData = new Bundle();
    	userData.putLong("UserID", userId);
	    intent.putExtras(userData);
	    spec = tabHost.newTabSpec("TimeClock").setIndicator("Time Clock",
	    		res.getDrawable(R.drawable.ic_menu_duration)) 
	            .setContent(intent);
	    tabHost.addTab(spec);	    

	    intent = new Intent().setClass(this, ScheduleActivity.class);
	    userData = new Bundle();
    	userData.putLong("UserID", userId);
    	intent.putExtras(userData);
	    spec = tabHost.newTabSpec("Schedule").setIndicator("Schedule",
	    		res.getDrawable(R.drawable.ic_menu_agenda)) 
	            .setContent(intent);
	    tabHost.addTab(spec);		    
	    
	    tabHost.setCurrentTab(0);

	}
}

AlertActivity.java:

/**
 * 
 */
package com.allpropestservices.bugpromobile;

import java.util.ArrayList;
import java.util.Date;
import android.app.Activity;
import android.os.Bundle;
import android.widget.EditText;
import android.widget.TextView;

/**
 * @author J. Osako
 *
 */
public class AlertActivity extends Activity {
	// For logging and debugging
    private static final String TAG = "AlertActivity";

    private int position = 0;
	private ArrayList<Message> messages;
	private User user = null;

	/**
	 * 
	 */
	@Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.motd);
        
        Bundle b = getIntent().getExtras();
        Long userId = b.getLong("UserId");
        user = new User(this, userId);
        
        messages = Message.getAlertMessages(this, new Date(), 10, user);
        Message msg = messages.get(position);
       
        TextView banner = (TextView) findViewById(R.id.AlertBanner);
        EditText title = (EditText) findViewById(R.id.AlertTitle);
        EditText body = (EditText) findViewById(R.id.AlertText);
        
        banner.setText("Recent Alerts for " + user.getFullName());
        title.setText(msg.getTitle());
        body.setText(msg.getBody());
    }

}

I am not applying any intent filters in the layout file for ParentTabActivity; the layout is:

parent.xml

<?xml version="1.0" encoding="utf-8"?>
<TabHost xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@android:id/tabhost"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent">
    <LinearLayout
        android:orientation="vertical"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:padding="5dp">
        <TabWidget
            android:id="@android:id/tabs"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content" />
        <FrameLayout
            android:id="@android:id/tabcontent"
            android:layout_width="fill_parent"
            android:layout_height="fill_parent"
            android:padding="5dp" />
    </LinearLayout>
</TabHost>

I realize that it may be possible to avoid this issue by re-designing the TabActivity so that it uses Views instead of Activities, but I would prefer to keep the different tabs separated if at all possible.

Is there any way to make this design work, and if so, where am I making my error? Do I need to add an intent filter to either the parent layout or the child layouts? Would switching to a View-based design negatively impact the modularity of the app?

[Schol-R-LEA]

Problem solved; it turned out to be a typographical error ("UserID" rather than "UserId") in the ParentTabActivity. The fact that it was duplicated four times is particularly galling.