TextView is on different heights on different resolutions. DIP doesn't work

Question

The bottom property of below textView scales wrong, the TextView is on a different height on every Android device: See attached pictures.

public class MainActivity extends Activity {

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

    RelativeLayout relativeLayout = (RelativeLayout)findViewById(R.id.bar_holder);

    BarView view = new BarView(getApplicationContext());
    int width = (int) getApplicationContext().getResources().getDimension(R.dimen.bar_width_compare);
    int height = 200;
    RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(width, height);
    params.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM, RelativeLayout.TRUE);
    int left = (int) getApplicationContext().getResources().getDimension(R.dimen.bar_margin_left_right);
    int right = 0;
    int bottom = (int) getApplicationContext().getResources().getDimension(R.dimen.graph_margin_bar_compare_bottom);
    params.setMargins(left, 0, right, bottom);
    view.setBackgroundColor(getApplicationContext().getResources().getColor(R.color.bar_dark_blue));
    view.setLayoutParams(params);
    relativeLayout.addView(view);

    TextView textView = new TextView(getApplicationContext());
    textView.setText("   20  ");
    textView.setTextSize(20);
    textView.setTextColor(getApplicationContext().getResources().getColor(R.color.black_text));
    width = (int) getApplicationContext().getResources().getDimension(R.dimen.bar_width);
    height = 100;

    bottom = (int) getApplicationContext().getResources().getDimension(R.dimen.graph_margin_bar_bottom);
    int offset = getApplicationContext().getResources().getDimensionPixelOffset(R.dimen.graph_margin_bar_bottom);
    int pxSize =  getApplicationContext().getResources().getDimensionPixelSize(R.dimen.graph_margin_bar_bottom);



    RelativeLayout.LayoutParams params2 = new RelativeLayout.LayoutParams(width, height);
    params2.setMargins(0, 0, 0, bottom);
    params2.addRule(Gravity.CENTER_HORIZONTAL);
    params2.addRule(RelativeLayout.ALIGN_PARENT_BOTTOM);
    params2.addRule(RelativeLayout.ALIGN_LEFT, view.getId());
    textView.setLayoutParams(params2);
    relativeLayout.addView(textView);
    }
}

bars_layout.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="wrap_content"
android:layout_height="match_parent"
android:orientation="horizontal"
android:layout_marginTop="40dp" >


<RelativeLayout
    android:id="@+id/bar_holder"
    android:layout_width="wrap_content"
    android:layout_height="match_parent"
    android:layout_marginTop="20dp"
    android:layout_marginBottom="10dp" >


</RelativeLayout>
</LinearLayout>

dimens.xml

<resources>
    <dimen name="graph_margin_bar_bottom">40dp</dimen>
    <dimen name="bar_width_compare">25dp</dimen>
    <dimen name="bar_margin_left_right">10dp</dimen>
    <dimen name="graph_margin_bar_compare_bottom">50dp</dimen>
    <dimen name="bar_width">50dp</dimen>
</resources>

Here are 2 examples of phones, but it looks different on every phone...

Samsung Galaxy Tab 3 Lite (density1.0)

Samsung Galaxy S4 (density3.0)

Answer 1

setMargins(int,int,int,int) is using pixels, not DIP, so on every device same size in pixels looks different, you need to convert DIP into pixels and then setMargins() with that value