How to start PopupWindow or Dialog from input method service?

Question

I get the same exception when trying to popup a PopupWindow (or Dialog) from an InputMethodService:

FATAL EXCEPTION: main android.view.WindowManager$BadTokenException: Unable to add window -- token null is not valid; is your activity running? at android.view.ViewRoot.setView(ViewRoot.java:505) at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:177) at android.view.WindowManagerImpl.addView(WindowManagerImpl.java:91) at android.widget.PopupWindow.invokePopup(PopupWindow.java:828) at android.widget.PopupWindow.showAtLocation(PopupWindow.java:688) at mypackage.MyInputMethodService.onClick(MyInputMethodService.java:123) ... 

If I try to use the dialog instead, I get the same exception on the same ViewRoot.java line. Here is my code (abbreviated):

 public class MyInputMethodService extends InputMethodService implements View.OnClickListener { public void onClick(View v) { // This is the handler for View.OnClickListener LayoutInflater inflater = (LayoutInflater) this.getSystemService(Context.LAYOUT_INFLATER_SERVICE); PopupWindow pw = new PopupWindow(inflater.inflate(R.layout.popup_example, null, false), 100, 100, true); pw.showAtLocation(mInputView, Gravity.CENTER, 0, 0); // mInputView was previously created and returned by onCreateInputView() } } // end of MyInputMethodService 

and

 <?xml version="1.0" encoding="utf-8"?> <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:orientation="vertical" android:padding="10dip" android:layout_width="fill_parent" android:layout_height="wrap_content" > <TextView android:layout_width="fill_parent" android:layout_height="wrap_content" android:layout_marginTop="10dip" android:text="Test Pop-Up" /> </LinearLayout> 

I tried many variations of the above code, but always get the same exception for PopupWindows and Dialogs. For some reason, Toast warnings are triggered. Is there a special way to launch PopupWindow or Dialog from a Service (in particular, InputMethodService), and not Activity?

Thanks in advance,

Barry

Answer 1

In fact, I managed to do this:

  AlertDialog.Builder builder = new AlertDialog.Builder(this); builder.setTitle("Make your selection"); builder.setItems(items, new DialogInterface.OnClickListener() { public void onClick(DialogInterface dialog, int item) { // Do something with the selection } }); AlertDialog alert = builder.create(); Window window = alert.getWindow(); WindowManager.LayoutParams lp = window.getAttributes(); lp.token = mInputView.getWindowToken(); lp.type = WindowManager.LayoutParams.TYPE_APPLICATION_ATTACHED_DIALOG; window.setAttributes(lp); window.addFlags(WindowManager.LayoutParams.FLAG_ALT_FOCUSABLE_IM); alert.show();