The solutions I found to change the spinner dropdown icon where all:
1. create a custom drawable
dummy.xml(remember image size should be less)
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item>
<layer-list android:opacity="transparent">
<item android:width="60dp" android:gravity="left" android:start="20dp">
<bitmap android:src="@drawable/down_button_dummy_dummy" android:gravity="left"/>
</item>
</layer-list>
</item>
</selector>
layout file snippet be like
<android.support.v7.widget.CardView
android:layout_width="match_parent"
android:layout_height="wrap_content"
app:cardUseCompatPadding="true"
app:cardElevation="5dp"
>
<Spinner
android:layout_width="match_parent"
android:layout_height="100dp"
android:background="@drawable/dummy">
</Spinner>
</android.support.v7.widget.CardView>
click to see result layout image
Add theme to spinner
<Spinner style="@style/SpinnerTheme"
android:layout_width="match_parent"
android:layout_height="match_parent"/>
Add spinnerTheme to styles.xml
<style name="SpinnerTheme" parent="android:Widget.Spinner">
<item name="android:background">@drawable/spinner_background</item>
</style>
Add New -> "Vector Asset" to drawable with e.g. "ic_keyboard_arrow_down_24dp"
Add spinner_background.xml to drawable
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item>
<layer-list>
<item android:drawable="@drawable/ic_keyboard_arrow_down_24dp" android:gravity="center_vertical|right" android:right="5dp"/>
</layer-list>
</item>
</selector>
I have had a lot of difficulty with this as I have a custom spinner, if I setBackground then the Drawable would stretch. My solution to this was to add a drawable to the right of the Spinner TextView. Heres a code snippet from my Custom Spinner. The trick is to Override getView and customize the Textview as you wish.
public class NoTextSpinnerArrayAdapter extends ArrayAdapter<String> {
private String text = "0";
public NoTextSpinnerArrayAdapter(Context context, int textViewResourceId, List<String> objects) {
super(context, textViewResourceId, objects);
}
public void updateText(String text){
this.text = text;
notifyDataSetChanged();
}
public String getText(){
return text;
}
@NonNull
public View getView(int position, View convertView, @NonNull ViewGroup parent) {
View view = super.getView(position, convertView, parent);
TextView textView = view.findViewById(android.R.id.text1);
textView.setCompoundDrawablePadding(16);
textView.setCompoundDrawablesWithIntrinsicBounds(0, 0, R.drawable.ic_menu_white_24dp, 0);
textView.setGravity(Gravity.END);
textView.setText(text);
return view;
}
}
You also need to set the Spinner background to transparent:
<lifeunlocked.valueinvestingcheatsheet.views.SelectAgainSpinner
android:id="@+id/saved_tickers_spinner"
android:background="@android:color/transparent"
android:layout_width="60dp"
android:layout_height="match_parent"
tools:layout_editor_absoluteX="248dp"
tools:layout_editor_absoluteY="16dp" />
and my custom spinner if you want it....
public class SelectAgainSpinner extends android.support.v7.widget.AppCompatSpinner {
public SelectAgainSpinner(Context context) {
super(context);
}
public SelectAgainSpinner(Context context, AttributeSet attrs) {
super(context, attrs);
}
public SelectAgainSpinner(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
@Override
public void setPopupBackgroundDrawable(Drawable background) {
super.setPopupBackgroundDrawable(background);
}
@Override
public void setSelection(int position, boolean animate) {
boolean sameSelected = position == getSelectedItemPosition();
super.setSelection(position, animate);
if (sameSelected) {
// Spinner does not call the OnItemSelectedListener if the same item is selected, so do it manually now
if (getOnItemSelectedListener() != null) {
getOnItemSelectedListener().onItemSelected(this, getSelectedView(), position, getSelectedItemId());
}
}
}
@Override
public void setSelection(int position) {
boolean sameSelected = position == getSelectedItemPosition();
super.setSelection(position);
if (sameSelected) {
// Spinner does not call the OnItemSelectedListener if the same item is selected, so do it manually now
if (getOnItemSelectedListener() != null) {
getOnItemSelectedListener().onItemSelected(this, getSelectedView(), position, getSelectedItemId());
}
}
}
}
Try applying following style to your spinner using
style="@style/SpinnerTheme"
//Spinner Style:
<style name="SpinnerTheme" parent="android:Widget.Spinner">
<item name="android:background">@drawable/bg_spinner</item>
</style>
//bg_spinner.xml Replace the arrow_down_gray with your arrow
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item>
<layer-list>
<item>
<shape>
<gradient android:angle="90" android:endColor="#ffffff" android:startColor="#ffffff" android:type="linear" />
<stroke android:width="0.33dp" android:color="#0fb1fa" />
<corners android:radius="0dp" />
<padding android:bottom="3dp" android:left="3dp" android:right="3dp" android:top="3dp" />
</shape>
</item>
<item android:right="5dp">
<bitmap android:gravity="center_vertical|right" android:src="@drawable/arrow_down_gray" />
</item>
</layer-list>
</item>
</selector>
Without Using ANY Drop down Using your Drop Down ICON
<?xml version="1.0" encoding="utf-8"?>
<selector xmlns:android="http://schemas.android.com/apk/res/android">
<item>
<layer-list>
<item>
<shape>
<gradient android:angle="90" android:endColor="#ffffff" android:startColor="#ffffff" android:type="linear" /><!--For gradient background-->
<stroke android:width="1dp" android:color="#FFF" /><!--For Border background-->
<corners android:radius="0dp" /><!--For background corner-->
<padding android:bottom="3dp" android:left="3dp" android:right="6dp" android:top="3dp" /><!--For padding for all sides-->
</shape>
</item>
<item>
<bitmap android:gravity="center|right" android:src="@drawable/ic_down_arrow" /> // Replace with your Icon
</item>
</layer-list>
</item>
We can manage it by hiding the icon as i did:
<FrameLayout
android:layout_width="match_parent"
android:layout_height="wrap_content">
<Spinner android:id="@+id/fragment_filter_sp_users"
android:layout_width="match_parent"
android:background="@color/colorTransparent"
android:layout_height="wrap_content"/>
<ImageView
android:layout_gravity="end|bottom"
android:contentDescription="@null"
android:layout_marginBottom="@dimen/_5sdp"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:src="@drawable/ic_arrow_bottom"
/>
</FrameLayout>