Search Dialog (Android 2.2) wont appear
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I'm trying to implement a Search Dialog, but my "Search" button on the emulator is disabled and i can't test it.
Firstly i create searchable.xml in xml folder:

    <?xml version="1.0" encoding="utf-8"?>
        <searchable xmlns:android="http://schemas.android.com/apk/res/android"
             android:label="@string/app_name"
             android:hint="@string/cures">
        </searchable>

Secondly, in my Manifest file, in my activity where i have in list my items, i changed this code below:

    <activity
            android:name=".Third"
            android:label="@string/title_activity_third" >
            <intent-filter>
                <action android:name="android.intent.action.SEARCH" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
            <meta-data android:name="android.app.default_searchable"
                   android:value="@xml/searchable" />
        </activity>
So i want, when a user press the search button, some search bar to be presented and when he submits his query, in the same activity, my ListView to be modified due to the changes made in the search dialog. Also, my search button on the emulator is disabled and when u run my app on device, when pressing on the search button nothing happens.
In other posts i've saw that 2 activities should be created, but i fetch and present my data in the same activity, so still its mandatory to do 2 activities or not? Can you help me to understand this, because i've read so many articles and they are all the same.