How does android loads an activity on screen?

Question

In my application i have created an activity which is showing simple hello world message. In "AndroidManifest.xml" file i set label attribute as="welcome":

<activity
    android:name="com.example.dmo.MainActivity"
    android:label="Welcome" >
    <intent-filter>
        <action android:name="android.intent.action.MAIN" />

        <category android:name="android.intent.category.LAUNCHER" />
    </intent-filter>
</activity>

in in MainActivity.java file in onCreate() method I set the title of an activity as "Hello world" using setTitle("Hello World ");

@Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        setTitle("Hello World .");
    }

Now my issue is that . . When I run my app First of all only title bar is shown with title set as "Welcome" ie set from androidManifest.xml file . . Then after the delay of some miliseconds remaining GUI is displayed and title changes to "Hello World" ie from setTitle() in onCreate() . According to my knowledge onCreate() is the first method that is executed.

1. Now what I want is , I don't want this delay to be happened and activity should directly show the title from method ie Hello World .

2. I also want to know that why this delay occures and only title bar is shown first and rest GUI later.

Note: My condition is that I cant remove label from my manifest.xml file and still I want to do as mentioned above.

Answer 1

just do this

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
setTitle("Hello World .");        
setContentView(R.layout.activity_main);


}

you need to decide to change title before loading layout

Answer 2

The simple to display Hello world in title is

• Rename welcome to Hello world and no need to settitle on oncreate method

And the delay is due to loading the MainActivity . First of xml data of the activity is loaded and then oncreate is called which calls its super class and then only settitle is called.