java - Proper way to handle action bar up button?

Question

I use ActionBarSherlock (although I don't think it matters).

I have a Main activity and an About activity. I want the About activity to show the back-arrow by its logo, and do the proper animation and such. I don't know how to do this properly.

Currently, I have under onOptionsMenuItemSelected to launch the Main activity when the Up/Home button is pressed, but it's hacky and doesn't really work right. It plays the wrong animation, and handles multitasking poorly.

How do I set this up right?

Here's the part in my Main activity that launches the About:

Intent aboutIntent = new Intent(MainActivity.this, About.class);
MainActivity.this.startActivity(aboutIntent);

Here's my About activity:

package com.stevenschoen.test;

import android.content.Intent;
import android.os.Bundle;

import com.actionbarsherlock.app.SherlockActivity;
import com.actionbarsherlock.view.MenuItem;

public class About extends SherlockActivity {
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.about);

        getSupportActionBar().setDisplayHomeAsUpEnabled(true);
        getSupportActionBar().setDisplayShowTitleEnabled(false);
    }

    public boolean onOptionsItemSelected(MenuItem item) {
        switch (item.getItemId()) {

            case android.R.id.home:
                // app icon in action bar clicked; go home
                Intent intentHome = new Intent(this, MainActivity.class);
                intentHome.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
                startActivity(intentHome);
                return true;

            default:
                return super.onOptionsItemSelected(item);
        }
    }
}

Answer 1

Have you also tried this (taken from Android website here) :

in the manifest, for each activity X that needs to go to the main activity, add this to the code:

@Override
public boolean onOptionsItemSelected(MenuItem item) {
    switch (item.getItemId()) {
    // Respond to the action bar's Up/Home button
    case android.R.id.home:
        NavUtils.navigateUpFromSameTask(this);
        return true;
    }
    return super.onOptionsItemSelected(item);
}

and this to its manifest xml tag:

<meta-data
android:name="android.support.PARENT_ACTIVITY"
android:value="com.activities.MainActivity" />

if you need to still have the same state on the main activity, use this code instead :

Intent intent = NavUtils.getParentActivityIntent(this); 
intent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP|Intent.FLAG_ACTIVITY_SINGLE_TOP); 
NavUtils.navigateUpTo(this, intent);

if the API is 16 or above, you can add an attribute of parentActivityName with the path to the main activity instead of the metadata .