Hello Linear Layout

A LinearLayout is a GroupView that will lay child View elements vertically or horizontally.

1. Start a new project/Activity called HelloLinearLayout.

2. Open the layout file. Make it like so:

android

layout width="wrap content"

android

layout height="fill parent"

android

layout weight="1"/>

<TextView

android

text="blue"

android

gravity="center horizontal"

android

background="#0 0 0 0aa"

android

layout width="wrap content"

android

layout height="fill parent"

android

layout weight="1"/>

<TextView

android

text="yellow"

android

gravity="center horizontal"

android

background="#aaaa0 0"

android

layout width="wrap content"

android

layout height="fill parent"

android

layout weight="1"/>

</LinearLayout>

<LinearLayout

android:orientation="vertical"

android:layout width="fill parent"

android:layout height="fill parent"

android:layout weight="1">

<TextView

android

text="row one"

android

textSize="15pt"

android

layout width="fill parent"

android

layout height="wrap content"

android

layout weight="1"/>

<TextView

android

text="row two"

android

textSize="15pt"

android

layout width="fill parent"

android

layout height="wrap content"

android

layout weight="1"/>

<TextView

android

text="row three"

android

textSize="15pt"

android

layout width="fill parent"

android

layout height="wrap content"

android

layout weight="1"/>

<TextView

android

text="row four"

android

textSize="15pt"

android

layout width="fill parent"

android

layout height="wrap content"

android

layout weight="1"/>

</LinearLayout>

</LinearLayout>

Carefully inspect the XML. You'll notice how this layout works a lot like an HTML layout. There is one parent LinearLayout that is defined to lay its child elements vertically. The first child is another LinearLayout that uses a horizontal layout and the second uses a vertical layout. Each LinearLayout contains several TextView elements.

3. Now open the HelloLinearLayout Activity and be sure it loads this layout in the onCreate() method:

public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main);

R.layout.main refers to the main.xml layout file.

4. Run it.

Helle UntjrLayttit

NUf

Notice how the various XML attributes define the View's behavior. Pay attention to the effect of

the layout weight. Try experimenting with different values to see how the screen real estate is

distributed based on the weight of each element.

References

row one

• LinearLavout

row two

• TextView

row three

row four

0 0

Post a comment