How can I design this layout programmatically?

Question

I have a parent linear layout.

I need to put three buttons at the bottom of screen horizontally aligned not from XML but through Java code.
Button 1 should be at left of screen
Button 2 should be at bottom of screen
Button 3 should be at right of screen

This is the layout need to be designed:

What I understand is I have to add a relative layout to my parent layout. And some rules for the button.

This is what I tried

protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    l=(LinearLayout)findViewById(R.id.mainl);
    rl=new RelativeLayout(this);
    b1=new Button(this);
    b2=new Button(this);
    b3=new Button(this);
    b1.setText("Button 1");
    b2.setText("Button 2");
    b3.setText("Button 3");
    rl.setLayoutParams(new RelativeLayout.LayoutParams(LayoutParams.MATCH_PARENT,LayoutParams.WRAP_CONTENT));
    RelativeLayout.LayoutParams lay = new RelativeLayout.LayoutParams(
            RelativeLayout.LayoutParams.WRAP_CONTENT, 
            RelativeLayout.LayoutParams.WRAP_CONTENT);
    lay.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM);

    rl.addView(b1);
    rl.addView(b2);
    rl.addView(b3);

    l.addView(rl);

}

And also the buttons are not coming at bottom. They are coming at top of screen.

Activity_main.xml

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/mainl"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:orientation="vertical" >
</LinearLayout>

Answer 1

For adding button to RelativeLayout run time, you have to pass params values.

Try for placing button b1 on left:

RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
params.addRule(RelativeLayout.ALIGN_PARENT_LEFT, RelativeLayout.TRUE);
rl.addView(b1, params);

Answer 2

RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);

    params.addRule(RelativeLayout.ALIGN_PARENT_LEFT, RelativeLayout.TRUE);
    rl.addView(b1, params);


    RelativeLayout.LayoutParams params1 = new RelativeLayout.LayoutParams(LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
    params1.addRule(RelativeLayout.ALIGN_PARENT_RIGHT, RelativeLayout.TRUE);
    rl.addView(b3, params1);

    RelativeLayout.LayoutParams params2 = new RelativeLayout.LayoutParams
            ( (int) LayoutParams.WRAP_CONTENT, (int) LayoutParams.WRAP_CONTENT);

    params2.addRule(RelativeLayout.CENTER_HORIZONTAL);
    rl.addView(b2, params2);



LinearLayout.LayoutParams layoutParams =
                (RelativeLayout.LayoutParams) txt1.getLayoutParams();
    layoutParams.addRule(LinearLayout.BOTTOM, 1);

rl.setLayoutParams(layoutParams);

Answer 3

Try this

LinearLayout.LayoutParams layoutParams = new LinearLayout.LayoutParams(
            LayoutParams.MATCH_PARENT, LayoutParams.WRAP_CONTENT);
    layoutParams.gravity = Gravity.BOTTOM;
    rl.setLayoutParams(layoutParams);



    RelativeLayout.LayoutParams params1 = new RelativeLayout.LayoutParams(
            LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);

    params1.addRule(RelativeLayout.ALIGN_PARENT_LEFT, RelativeLayout.TRUE);

    RelativeLayout.LayoutParams params2 = new RelativeLayout.LayoutParams(
            LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT);
    params2.addRule(RelativeLayout.ALIGN_PARENT_RIGHT, RelativeLayout.TRUE);

    RelativeLayout.LayoutParams params3 = new RelativeLayout.LayoutParams(
            (int) LayoutParams.WRAP_CONTENT,
            (int) LayoutParams.WRAP_CONTENT);

    params3.addRule(RelativeLayout.CENTER_HORIZONTAL);

    rl.addView(b1, params1);
    rl.addView(b2, params3);
    rl.addView(b3, params2);

    l.addView(rl);

Answer 4

Try this one: XML file :

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/main"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:gravity="bottom"
    android:orientation="vertical"
    tools:context=".MainActivity" >

</LinearLayout>

And in JAVA file :

 LinearLayout main = (LinearLayout) findViewById(R.id.main);

        RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(
                android.widget.RelativeLayout.LayoutParams.MATCH_PARENT,
                android.widget.RelativeLayout.LayoutParams.WRAP_CONTENT);
        RelativeLayout ll = new RelativeLayout(getBaseContext());

        RelativeLayout.LayoutParams params1 = new RelativeLayout.LayoutParams(
                android.widget.RelativeLayout.LayoutParams.WRAP_CONTENT,
                android.widget.RelativeLayout.LayoutParams.WRAP_CONTENT);
        params1.addRule(RelativeLayout.ALIGN_PARENT_LEFT, RelativeLayout.TRUE);
        RelativeLayout.LayoutParams params2 = new RelativeLayout.LayoutParams(
                android.widget.RelativeLayout.LayoutParams.WRAP_CONTENT,
                android.widget.RelativeLayout.LayoutParams.WRAP_CONTENT);
        params2.addRule(RelativeLayout.ALIGN_PARENT_RIGHT, RelativeLayout.TRUE);

        RelativeLayout.LayoutParams params3 = new RelativeLayout.LayoutParams(
                android.widget.RelativeLayout.LayoutParams.WRAP_CONTENT,
                android.widget.RelativeLayout.LayoutParams.WRAP_CONTENT);
        params3.addRule(RelativeLayout.CENTER_HORIZONTAL, RelativeLayout.TRUE);

        Button btn1 = new Button(getBaseContext());
        Button btn2 = new Button(getBaseContext());
        Button btn3 = new Button(getBaseContext());

        btn1.setText("One");
        btn2.setText("Two");
        btn3.setText("Three");

        ll.addView(btn1, params1);
        ll.addView(btn2, params2);
        ll.addView(btn3, params3);

        main.addView(ll, params);

Hope this will help you.

Answer 5

I have created layout programmatically use this code:

public class MainActivity extends Activity {
    private LinearLayout layout; 
    private RelativeLayout lay;
    private Button btn1, btn2, btn3;

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

        layout = (LinearLayout)findViewById(R.id.ff);
        lay = new RelativeLayout(this);
        RelativeLayout.LayoutParams layout_params = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT,RelativeLayout.LayoutParams.WRAP_CONTENT);
        layout_params.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM);
        lay.setLayoutParams(layout_params);

        //lay.setLayoutParams(layout_params);
        btn1 = new Button(this);
        btn1.setText("ButtonA");
        btn2 = new Button(this);
        btn2.setText("ButtonB");
        btn3 = new Button(this);
        btn3.setText("ButtonC");

        RelativeLayout.LayoutParams button_params1 = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT,RelativeLayout.LayoutParams.WRAP_CONTENT);
        button_params1.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM);
        button_params1.addRule(RelativeLayout.ALIGN_PARENT_LEFT);
        btn1.setLayoutParams(button_params1);

        RelativeLayout.LayoutParams button_params2 = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT,RelativeLayout.LayoutParams.WRAP_CONTENT);
        button_params2.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM);
        button_params2.addRule(RelativeLayout.CENTER_HORIZONTAL);
        btn2.setLayoutParams(button_params2);

        RelativeLayout.LayoutParams button_params3 = new RelativeLayout.LayoutParams(RelativeLayout.LayoutParams.WRAP_CONTENT,RelativeLayout.LayoutParams.WRAP_CONTENT);
        button_params3.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM);
        button_params3.addRule(RelativeLayout.ALIGN_PARENT_RIGHT);
        btn3.setLayoutParams(button_params3);

        lay.addView(btn1);
        lay.addView(btn2);
        lay.addView(btn3);
        layout.addView(lay);



    }
}