Android - Keep UI organised regardless screen size

Question

I am making a game and while my UI is very well organised in my Preview Device it gets messed up in the Emulator device and thats because of the different screen size ! I tried to achieve to have an organised UI programmatically , meaning that i firstly measure the screen size and depending on how big or small it is i create buttons,images,textviews that are for this size...

 btn2.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View view) {
            btn_params=new RelativeLayout.LayoutParams(40,40);
            btn_params.rightMargin=0;
            btn_params.bottomMargin=0;
            btn1.setLayoutParams(btn_params);

            waterlily_params=new RelativeLayout.LayoutParams(layout.getHeight()/3,layout.getHeight()/3);
            waterlily_params.leftMargin=layout.getWidth()/2;
            waterlily_params.bottomMargin=0;
            iv2.setLayoutParams(waterlily_params);

            frog_params=new RelativeLayout.LayoutParams(iv2.getHeight()/2,iv2.getHeight()/2);
            frog_params.leftMargin=layout.getWidth()/2;
            frog_params.bottomMargin=0;
            iv1.setLayoutParams(frog_params);

            iv2.setVisibility(view.VISIBLE);
            iv1.setVisibility(view.VISIBLE);
            btn2.setVisibility(view.GONE);
            btn1.setVisibility(view.VISIBLE);

        }
    });

but seriously the above doesnt seem right and it doesnt work So my question is how to make a UI that will match every screen ?

here is the xml of the specific activity :

 im using xml files ! Here is the xml file of the specific activity :



<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
android:paddingBottom="@dimen/activity_vertical_margin"
tools:context="com.example.user.catchthefly.MainGame"
android:clickable="true"
android:id="@+id/MyLayout"
android:focusableInTouchMode="true">


<ImageView
    android:layout_width="300dp"
    android:layout_height="200dp"
    android:id="@+id/waterlily"
    android:background="@drawable/water_lily"
    android:layout_alignParentBottom="true"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:visibility="invisible" />

<ImageView
    android:layout_width="150dp"
    android:layout_height="150dp"
    android:id="@+id/frog"
    android:background="@drawable/f132"
    android:layout_gravity="bottom"
    android:layout_alignBottom="@+id/waterlily"
    android:layout_centerHorizontal="true"
    android:visibility="invisible" />

<Button
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:text="Tap Here To Start Your Game"
    android:id="@+id/StartingButton"
    android:enabled="true"
    android:textSize="30dp"
    android:layout_alignParentTop="true"
    android:layout_alignParentLeft="true"
    android:layout_alignParentStart="true"
    android:background="#00000000" />

<Button
    android:layout_width="40dp"
    android:layout_height="40dp"
    android:id="@+id/MovingObj"
    android:background="#ffff00e1"
    android:layout_above="@+id/StartingButton"
    android:layout_toLeftOf="@+id/frog"
    android:layout_toStartOf="@+id/frog"
    android:visibility="invisible" />
</RelativeLayout>

Answer 1

1. Did you read http://developer.android.com/guide/practices/screens_support.html?

2. Did you consider to use a game engine https://github.com/nicolasgramlich/AndEngine ? It take care about properly rendering on various devices and a lot of other stuff.

Answer 2

You need to use xml layout folder. Do you need to create your layout programmatically or can you use xml files? You should create xml resources and inflate them.