RelativeLayout with ImageView - calculate position of elements - android-layout

Question

I have a problem with my android code. I have the following code
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:id="#+id/main_layout_container"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="#000000"
android:orientation="vertical">
<ImageView
android:id="#+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:adjustViewBounds="true"
android:layout_centerVertical="true"
android:src="#drawable/pdf" />
<TextView
android:id="#+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignTop="#+id/imageView1"
android:layout_alignLeft="#+id/imageView1"
android:text="Test-Label"
android:textColor="#color/red" />
</RelativeLayout>
I want to position the textview now in my imageview and use the following code
ImageView iv = (ImageView) findViewById(R.id.imageView1);
int width = iv.getWidth();
int height = iv.getHeight();
float percentMarginTop = 58f;
float percentMarginLeft = 65f;
float percentTextSize = 3f;
float marginTop = height / 100f * percentMarginTop;
float marginLeft = width / 100f * percentMarginLeft;
TextView tv = (TextView) findViewById(R.id.textView1);
tv.setTextSize(TypedValue.COMPLEX_UNIT_DIP, Math.round(height / 100f * percentTextSize));
RelativeLayout.LayoutParams lpTv = (RelativeLayout.LayoutParams) tv.getLayoutParams();
lpTv.topMargin = Math.round(marginTop);
lpTv.leftMargin = Math.round(marginLeft);
So I want to position the elements with the percentage values calculated of the actual width and height of the imageview. So in my opinion the elements should position correct on each device not carrying about the density (ldpi, mdpi, xhdpi, ...) and screen size (small, normal, large, xlarge, ...) but the position on a handy (4") is correct but not correct on another device like a tablet (10"). How could that be when I'm working with percentages on the given ImageView?

Answer 1

Looks like it was a dumb beginner mistake I didn't want to see or wanted to ignore it ;)
width / 100 returns not the float value, but the int value. And then the whole calculation fails due to a false value which gets multiplicated.
I changed my code which is now a working snippet