text.Layout.getLineTop() returns wrong Y coordinates on the second line, probably because of the first line has wrong height. Something to do with wrong scale by 0.2?

Code to reproduce:

<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:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity" >
<TextView
android:id="@+id/textView1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:text="Line 0\nLine 1\nLine 2\nLine 3\nLine 4"
android:textSize="10sp" />
<Button
android:id="@+id/button1"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/textView1"
android:layout_alignParentBottom="true"
android:onClick="onBtnClick"
android:text="Button" />
</RelativeLayout>

public class MainActivity extends Activity {
Layout layout;
TextView tv;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
tv = (TextView) findViewById(R.id.textView1);
}
public void onBtnClick(View view) {
float density = getResources().getDisplayMetrics().density;
layout = tv.getLayout();
int line_top = 0;
int previous_line = 0;
for (int i = 0; i < layout.getLineCount(); i++) {
line_top = layout.getLineTop(i);
Log.d("bug", "Text Size: "
+ (int) (tv.getTextSize() / density + 0.5f)
+ " line_top: " + line_top + " curr - prev: "
+ (line_top - previous_line));
previous_line = line_top;
}
}
}

Set 'bug' as Log filter..

Nexus7 emulator,

TextView text size 10sp:

Text Size: 10 line_top: 0 curr - prev: 0
Text Size: 10 line_top: 17 curr - prev: 17
Text Size: 10 line_top: 32 curr - prev: 15
Text Size: 10 line_top: 47 curr - prev: 15
Text Size: 10 line_top: 62 curr - prev: 15

*** The first's line height is 17, the rest lines are 15
*** 17 - 15 = 2 => 0.2 of the text size.

TextView text size 20sp:

Text Size: 20 line_top: 0 curr - prev: 0
Text Size: 20 line_top: 36 curr - prev: 36
Text Size: 20 line_top: 68 curr - prev: 32
Text Size: 20 line_top: 100 curr - prev: 32
Text Size: 20 line_top: 132 curr - prev: 32

*** Same with text size 20.. 36 - 32 = 4 => 0.2 of the text size.

TextView text size 30sp:

Text Size: 30 line_top: 0 curr - prev: 0
Text Size: 30 line_top: 53 curr - prev: 53
Text Size: 30 line_top: 100 curr - prev: 47
Text Size: 30 line_top: 147 curr - prev: 47
Text Size: 30 line_top: 194 curr - prev: 47

*** Same with text size 30.. 53 - 47 = 6 => 0.2 of the text size.

Also done with Nexus S emulator and SG4 real device. Same 0.2 scale error.

Issue 36977332

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