Soft keyboard's POPUP layout

I'm developing a soft keyboard and doing well, but I don't know how to customize the popup layout for a long keypress.

My KeyboardView:

<?xml version="1.0" encoding="UTF-8"?>
<android.inputmethodservice.KeyboardView
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/keyboard"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_alignParentBottom="true"
android:keyPreviewLayout="@layout/preview"
android:keyBackground="@drawable/key_selector"
android:shadowRadius="0.0"
android:keyTextColor="#000000"
/>

My keyboard layout:

<?xml version="1.0" encoding="utf-8"?>
<Keyboard xmlns:android="http://schemas.android.com/apk/res/android"
android:keyWidth="10%p"
android:keyHeight="10%p">

<Row android:verticalGap="1%p"  android:horizontalGap="0.5%p" android:keyHeight="8%p" android:keyWidth="9.6%p">
    <Key android:codes="113"    android:keyLabel="q" />
    <Key android:codes="119"    android:keyLabel="w" />
    <Key android:codes="101"    android:keyLabel="e"  
        />
    <Key android:codes="114"    android:keyLabel="r" />
    <Key android:codes="116"    android:keyLabel="t" />
    <Key android:codes="121"    android:keyLabel="y"
         android:popupKeyboard="@xml/keyboard_popup" android:popupCharacters="yýÿ"/>
    <Key android:codes="117"    android:keyLabel="u"
         android:popupKeyboard="@xml/keyboard_popup" android:popupCharacters="uúùũûü"/>
    <Key android:codes="105"    android:keyLabel="i" 
         android:popupKeyboard="@xml/keyboard_popup" android:popupCharacters="iíìĩîï"/>
    <Key android:codes="111"    android:keyLabel="o" 
         android:popupKeyboard="@xml/keyboard_popup" android:popupCharacters="oóò&#245;ôö" />
    <Key android:codes="112"    android:keyLabel="p" />
</Row>
<Row android:verticalGap="1%p" android:horizontalGap="0.5%p" android:keyHeight="8%p" android:keyWidth="9.6%p">
    <Key android:codes="97"    android:keyLabel="a" android:keyEdgeFlags="left" android:horizontalGap="5%p"
         android:popupKeyboard="@xml/keyboard_popup" android:popupCharacters="aáà&#227;âä"/>
    <Key android:codes="115"    android:keyLabel="s" />
    <Key android:codes="100"    android:keyLabel="d" />
    <Key android:codes="102"    android:keyLabel="f" />
    <Key android:codes="103"    android:keyLabel="g" />
    <Key android:codes="104"    android:keyLabel="h" />
    <Key android:codes="106"    android:keyLabel="j" />
    <Key android:codes="107"    android:keyLabel="k" />
    <Key android:codes="108"    android:keyLabel="l" />
</Row>
<Row android:verticalGap="1%p"  android:horizontalGap="0.5%p" android:keyHeight="8%p" android:keyWidth="9.6%p">
    <Key android:codes="3"      android:keyIcon="@drawable/keyboard_shift_off" 
         android:keyHeight="7.6%p" android:keyWidth="13.7%p"/>
    <Key android:codes="122"    android:keyLabel="z" android:horizontalGap="1%p"/>
    <Key android:codes="120"    android:keyLabel="x" />
    <Key android:codes="99"     android:keyLabel="c"
         android:popupKeyboard="@xml/keyboard_popup" android:popupCharacters="cç"/>
    <Key android:codes="118"    android:keyLabel="v" />
    <Key android:codes="98"     android:keyLabel="b" />
    <Key android:codes="110"    android:keyLabel="n"
         android:popupKeyboard="@xml/keyboard_popup" android:popupCharacters="nñ"/>
    <Key android:codes="109"    android:keyLabel="m" />
    <Key android:codes="-5"     android:keyIcon="@drawable/sym_keyboard_delete_dim"
        android:keyHeight="7.6%p" android:keyWidth="13.7%p" 
        android:horizontalGap="1%p"/>
</Row>
<Row android:verticalGap="1%p"  android:horizontalGap="0.5%p" android:keyHeight="8%p" android:keyWidth="9.6%p">
    <Key android:codes="-16"    android:keyIcon="@drawable/keyboard_symbol"
         android:keyHeight="7.6%p" android:keyWidth="18.7%p"/>
    <Key android:codes="44"     android:keyLabel="," android:horizontalGap="1%p"/>
    <Key android:codes="32"     android:keyIcon="@drawable/sym_keyboard_feedback_space" android:keyWidth="40%p"/>
    <Key android:codes="46"     android:keyLabel="."/>
    <Key android:codes="-3"     android:keyIcon="@drawable/keyboard_go" 
        android:keyHeight="7.6%p" android:keyWidth="18.5%p" android:horizontalGap="1%p"/>
</Row>

The keyboard popup XML:

<?xml version="1.0" encoding="utf-8"?>
<Keyboard xmlns:android="http://schemas.android.com/apk/res/android"
android:keyWidth="10%p"
android:keyHeight="10%p">
</Keyboard>

I tried putting keyBackground and background properties everywhere, but not successfully. I tried to put:

android:popupLayout="@layout/keyboard"

...On the keyboardView but get nullpointer, maybe I'm putting a wrong XML in that parameter?

In the keyboard popup XML that I put here:

android:popupKeyboard="@xml/keyboard_popup"

I can change the layout's size, key size, key gap, and other things, but can't change the colors or backgrounds.

The key preview also is doing well, I put this on the keyboardView:

android:keyPreviewLayout="@layout/preview"

...And it works. I think the popup should be the same way, but it's not.

How can I customize the popup window that appears for a long keypress?

Well, it is not exactly what I was looking for, but this resolves the problem.

I made my own keyboard view and made a popup window to show when a key is long pressed.

public class MyKeyboardView extends KeyboardView{
   @Override
   protected boolean onLongPress(final Key popupKey) {
        final View custom = LayoutInflater.from(context)
        .inflate(R.layout.popup_layout, new FrameLayout(context));
        popup = new PopupWindow(context);
        popup.setWidth(WindowManager.LayoutParams.WRAP_CONTENT);
        popup.setHeight(WindowManager.LayoutParams.WRAP_CONTENT);
        popup.showAtLocation(this, Gravity.NO_GRAVITY, popupKey.x, popupKey.y-50);
   }
}

This way you can customize the popup any way you want in the xml.

But this is not the correct answer, if you know a better way to do this please answer this question.