Android spinner vertical offset changed

Question

I'm using a Spinner below a title (TextView). It is initially set to View.GONE and when the title is clicked, Spinner is set to View.VISIBLE and the popup window is shown using performClick() below the title, which is what I want.

But I asynchronously update the BaseAdapter to add more items to the Spinner when it is still VISIBLE. After the update the Spinner is moved upwards and is overlaying on the title. How can I fix this?

I have used android:dropDownVerticalOffset, but shows the same behaviour after update.

My layout :

 <LinearLayout 
   android:layout_width="match_parent"
   android:layout_height="match_parent"
   android:orientation="vertical">

<TextView
    android:id="@+id/title"
    android:layout_width="match_parent"
    android:layout_height="wrap_content" />

<FrameLayout
    android:layout_width="match_parent"
    android:layout_height="wrap_content">

    <LinearLayout
        android:id="@+id/some_other_layout"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">
    </LinearLayout>

    <android.support.v7.widget.AppCompatSpinner
        android:id="@+id/spinner"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:animateLayoutChanges="true"
        android:background="@null"
        android:overlapAnchor="true"
        android:spinnerMode="dropdown"
        android:visibility="gone"></android.support.v7.widget.AppCompatSpinner>
</FrameLayout>
</LinearLayout>

Answer 1

Ok. I Tried running you problem with some slight adjustments on my mobile, and I find no issues. To simulate your asynchronous addition of items, I added a button.It's OnClick will add items to the adapter. Next, Instead of extending BaseAdapter, I just used an ArrayAdapter. And, I just added weights to the LinearLayout to help me with the layout look.

Here Is The Layout :

<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
>


        <TextView
            android:id="@+id/title"
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            android:text="Title"
            android:textSize="20dp"
            android:gravity="center"
            android:textColor="@android:color/black"
        />

        <FrameLayout
            android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:layout_weight="1"
            >

            <LinearLayout
                android:id="@+id/some_other_layout"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:orientation="vertical">
            </LinearLayout>

            <android.support.v7.widget.AppCompatSpinner
                android:id="@+id/spinner"
                android:layout_width="match_parent"
                android:layout_height="wrap_content"
                android:animateLayoutChanges="true"
                android:background="@null"
                android:overlapAnchor="true"
                android:spinnerMode="dropdown"></android.support.v7.widget.AppCompatSpinner>
        </FrameLayout>
    <Button
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1"
        android:text="Load Adapter"
        android:id="@+id/button"
    />

</LinearLayout>

And Here Is the Code for the Activity :

public class MainActivity extends AppCompatActivity {

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


    Spinner spinner;
    Button button;

    @Override
    protected void onResume() {
        super.onResume();
        spinner = (Spinner) findViewById(R.id.spinner);
        button = (Button) findViewById(R.id.button);

        List<String> list = new ArrayList<>();
        list.add(getRandomStringInRange('A','Z',5));
        ArrayAdapter<String> adapter= new ArrayAdapter(MainActivity.this,android.R.layout.simple_spinner_item,list);
        adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
        spinner.setAdapter(adapter);

        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                ArrayAdapter<String> adapter = (ArrayAdapter<String>) spinner.getAdapter();
                adapter.add(getRandomStringInRange('A','Z',5));
            }
        });

    }
    public int getRandomNumberInRange(int lower,int higher){
        int range = higher-lower;
        range=(int)(range*Math.random());
        return lower + range;
    }

    public String getRandomStringInRange(char lower,char higher,int length){

        String str ="";
        for(int i=0;i<length;i++)
            str+=(char)(getRandomNumberInRange(lower,higher));
        return str;
    }

}

I did not find the spinner overlapping the title or it moving at all.

It's working fine.

If you want,I'll send you screenshots. Please tell me if you are facing any other issues

Answer 2

I couldn't really find a solution for this. But solved by setting fixed height for the spinner as mentioned in this solution.

Spinner spinner = (Spinner) findViewById(R.id.spinner);
try {
    Field popup = Spinner.class.getDeclaredField("mPopup");
    popup.setAccessible(true);

    // Get private mPopup member variable and try cast to ListPopupWindow
    android.widget.ListPopupWindow popupWindow = (android.widget.ListPopupWindow) popup.get(spinner);

    // Set popupWindow height to 500px
    popupWindow.setHeight(500);
}
catch (NoClassDefFoundError | ClassCastException | NoSuchFieldException | IllegalAccessException e) {
    // silently fail...
}