Why buttons has the same size on multiple screens (Android 1.6+)?

Question

Please help me with one problem. When I change min sdk version from 3 (Android 1.5) to 4 (1.6) or higher, all buttons and textviews have the same size on multiple screens although I use dp and sp units. Why might this be?

Simple example (main.xml):

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="fill_parent"
              android:layout_height="fill_parent"
>
    <Button 
        android:id="@+id/button"
        android:layout_width="300dp"
        android:layout_height="300dp"
        android:text="OK"
        android:layout_centerInParent="true"
    />
</LinearLayout>

Screenshot from Google Nexus 7: http://s019.radikal.ru/i601/1312/fd/e769f6e3a690.png

Screenshot from Sony Ericsson Xperia Play: http://s019.radikal.ru/i600/1312/9d/6b3f580e7503.png

Answer 1

Create dimen.xml for following folder as per your requirement:

1. values
2. values-hdpi
3. values-ldpi
4. values-mdpi
5. values-sw600dp
6. values-sw720dp-land etc...

and code for that dimen.xml and give xxxdp as you want:

<resources>

    <!-- Default screen margins, per the Android Design guidelines. -->
    <dimen name="button_width">300dp</dimen>
    <dimen name="button_height">300dp</dimen>

</resources>

then after you xml file like:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
              android:orientation="vertical"
              android:layout_width="fill_parent"
              android:layout_height="fill_parent">
    <Button 
        android:id="@+id/button"
        android:layout_width="@dimen/button_width"
        android:layout_height="@dimen/button_height"
        android:text="OK"
        android:layout_centerInParent="true" />
</LinearLayout>

---

FOR PROGRAMMATICALLY:

This also works:

getResources().getDisplayMetrics().density;

This will give you:

• 0.75 - ldpi
• 1.0 - mdpi
• 1.5 - hdpi
• 2.0 - xhdpi
• 3.0 - xxhdpi
• 4.0 - xxxhdpi

May it'll be Helpful...

Thanks...