Android - Tabhost working in Activity class

Question

OK, I must be overlooking something silly because I am unable to get my tabhost to display in my Activity class. I am getting the dreaded force close when I try to run the app. It will work if i extend TabActivity, but I can't do that [see edit below] because once I move the code from my prototype project its going to be in a custom class that inherits from Activity.

Here is the XML layout:

<?xml version="1.0" encoding="utf-8"?>
<TabHost xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+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">        
        <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" />
    </LinearLayout>
</TabHost>

And here is the class that is trying to create and display the TabHost:

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.util.Log;
import android.widget.TabHost;

public class my_proto extends Activity
{   
   /** Called when the activity is first created. */
   @Override
   public void onCreate(Bundle savedInstanceState)
   {
      Log.i(this.toString(), "OnCreate");

      super.onCreate(savedInstanceState);
      setContentView(R.layout.main);

      Log.i(this.toString(), "get tab host");
      TabHost host = (TabHost)findViewById(R.id.tabhost); 
      host.setup();

      Log.i(this.toString(), "add tabs");
      host.addTab(host.newTabSpec("one")
                      .setIndicator("First Results")
                      .setContent(new Intent(this, FirstResultsListViewActivity.class)));

      host.addTab(host.newTabSpec("two")
                      .setIndicator("Second Results")
                      .setContent(new Intent(this, SecondResultsListViewActivity.class)));

      Log.i(this.toString(), "adjust tab size");
      host.getTabWidget().getChildAt(0).getLayoutParams().height = 35;
      host.getTabWidget().getChildAt(1).getLayoutParams().height = 35;

   }// end onCreate

}// end class my_proto

This is the error I get in the log.

11-17 16:49:51.271: INFO/com.my_proto.my_proto@43b80b50(1302): OnCreate
11-17 16:49:51.472: INFO/com.my_proto.my_proto@43b80b50(1302): get tab host
11-17 16:49:51.480: INFO/com.my_proto.my_proto@43b80b50(1302): add tabs
11-17 16:49:51.521: DEBUG/AndroidRuntime(1302): Shutting down VM
11-17 16:49:51.521: WARN/dalvikvm(1302): threadid=3: thread exiting with uncaught exception (group=0x4001b188)
11-17 16:49:51.530: ERROR/AndroidRuntime(1302): Uncaught handler: thread main exiting due to uncaught exception
11-17 16:49:51.552: ERROR/AndroidRuntime(1302): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.my_proto/com.my_proto.my_proto}: java.lang.IllegalStateException: Did you forget to call 'public void setup(LocalActivityManager activityGroup)'?
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2496)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2512)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at android.app.ActivityThread.access$2200(ActivityThread.java:119)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1863)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at android.os.Handler.dispatchMessage(Handler.java:99)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at android.os.Looper.loop(Looper.java:123)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at android.app.ActivityThread.main(ActivityThread.java:4363)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at java.lang.reflect.Method.invokeNative(Native Method)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at java.lang.reflect.Method.invoke(Method.java:521)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at dalvik.system.NativeStart.main(Native Method)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302): Caused by: java.lang.IllegalStateException: Did you forget to call 'public void setup(LocalActivityManager activityGroup)'?
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at android.widget.TabHost$IntentContentStrategy.getContentView(TabHost.java:646)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at android.widget.TabHost.setCurrentTab(TabHost.java:320)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at android.widget.TabHost.addTab(TabHost.java:213)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at com.mc_proto.mc_proto.onCreate(my_proto.java:29)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2459)
11-17 16:49:51.552: ERROR/AndroidRuntime(1302):     ... 11 more

Its complaining about not calling setup, but I am calling it. There is another version of setup that needs some kind of LocalActivityMananger. I have tried replacing the call to setup the call below but no luck.

LocalActivityManager mLocalActivityManager = new LocalActivityManager(this, false);
host.setup(mLocalActivityManager);

[edit] The call above didn't work so I took it back out. Although I was getting a new error logged.

11-17 20:24:58.382: ERROR/AndroidRuntime(1432): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.my_proto/com.my_proto.my_proto}: java.lang.IllegalStateException: Activities can't be added until the containing group has been created.

[edit] Based on some of the comments below I realized I need to be clearer about why I can't inherit from TabActivity. Once I have the prototype working I need to port this into an existing app's screen that inherits from Activity. I will need to load the TabHost into a Layout within that Activity. It will basically be a LinearLayout with a row of status icons, followed my a LinearLayout with the Tabhost in it. I know that if I can get this working I can move onto the next phase. Thanks!

---------------------------
|      status icons       |
---------------------------
|    Tab, Tab, Tab        |
|                         |
|                         |
|                         | 
---------------------------
|      status icons       |
---------------------------

Cardiomegaly

Answer 1

Ok I figured it out. Apparently, TabActivity extends ActivityGroup, which extends Activity. But in your code your class extends Activity which is not an activity group.

So there are two options:

1) If you want the tab content to be activities, have your class extend ActivityGroup (instead of Activity). Then your call to setup should be host.setup(getLocalActivityManager());

This way you are emulating the TabActivity source code.

2) If you can have your tab content be views (vs activities), keep your class as extending from Activity, and keep your call to setup(). But for the setContent part do something like this:

host.addTab(host.newTabSpec("two")
                .setIndicator("Second Results")
                .setContent(new TabContentFactory() {

                    public View createTabContent(String tag) {
                        return new TextView(TestActivity.this);
                    }
                }));

And then define your list view inside createTabContent (that's usually what I do - I prefer using views instead of activities as the contents of the tabs).

Relict

thanks for all your time. I'm still not quite there, if you look at my picture above I'm going to need to wedge the tab host into a center pane of a screen whose base class is Activity. I'm surprised that using LocalActivityManager mLocalActivityManager = new LocalActivityManager(this, false); host.setup(mLocalActivityManager); doesn't work when using an Activity. I saw your tutorial on using ListViews in the tabs and I;m going to look that over. Currently each of my tabs is a ListView, although that won't always be the case. Thanks! – Cardiomegaly

Answer 2

If you have a scenario in which you need to use Activity class for your Tabhost you can try the following it works.

    tabHost = (TabHost) findViewById(R.id.tabhost); //here tabHost will be your Tabhost
    LocalActivityManager mLocalActivityManager = new LocalActivityManager(mActivity, false);
    mLocalActivityManager.dispatchCreate(state); // state will be bundle your activity state which you get in onCreate
    tabHost.setup(mLocalActivityManager);

Rhynchocephalian

This works and you still keep your activity as a regular activity. – Memphis

This worked for me. Although LocalActivityManager is deprecated, this may still be a plausible solution till you switch over to using the Fragments API. – Specialty

LocalActivityManager is deprecated – Trapezohedron

Answer 3

Had the same problem: this question helps Android: TabHost without TabActivity

Apparently, you only need to add one line:

LocalActivityManager mLocalActivityManager = new LocalActivityManager(this, false);
mLocalActivityManager.dispatchCreate(savedInstanceState);
host.setup(mLocalActivityManager);

Cycle

Answer 4

android:id="@+id/tabhost" doesnt work for me. I have to write android:id="@android:id/tabhost"

Valenza

Answer 5

I changed the class to

public class my_proto extends ActivityGroup

and change the following:

this.mHost = (TabHost) findViewById(R.id.tabhost);
this.mHost.setup(getLocalActivityManager());

It seems ok for me

Barometrograph

ActivityGroup is deprecated – Trapezohedron

Answer 6

Change the class declaration which has this:

public class my_proto extends Activity

to

public class my_proto extends TabActivity

Capitol

I can't do that. I stated in my desciption "its going to need to inherit from a custom class that inherits from Activity" – Cardiomegaly

@cbursk: that was not there when I answered here... that was edited after I posted the answer... – Capitol

It was there. I added the details after your post. No biggie. – Cardiomegaly

Answer 7

What tommie says is true. You should also look at the tutorial here http://developer.android.com/resources/tutorials/views/hello-tabwidget.html

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