Found the solution....
Add this textwatcher to the multiautocompletetextview
private TextWatcher textWather = new TextWatcher() {
int noOfCharAdded=0;int noOfCharDeleted=0;
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {
startIdx=start;
}
@Override
public void beforeTextChanged(CharSequence s, int start, int count,int after) {
noOfCharAdded=after;
noOfCharDeleted=count;
}
@Override
public void afterTextChanged(Editable s) {
Editable buffer = s;
int start = multiContentText.getSelectionStart()<0?0:multiContentText.getSelectionStart();
int end = multiContentText.getSelectionEnd()<0?0:multiContentText.getSelectionEnd();
if(noOfCharAdded==0 && noOfCharDeleted==1){ //if space is deleted
if (start == end && delPrevText) {
ImageSpan link[] = buffer.getSpans(start, end,ImageSpan.class);
if (link.length > 0) {
buffer.replace(buffer.getSpanStart(link[0]),buffer.getSpanEnd(link[0]),"");
buffer.removeSpan(link[0]);
}
}
delPrevText=true;
multiContentText.setSelection(multiContentText.getText().length());
}
else if(noOfCharAdded==0 && noOfCharDeleted>1){//if the whole word is deleted
if(buffer.length()>0){
if(start<buffer.length()){
delPrevText=false;
if(buffer.charAt(start)==' '){
buffer.replace(start,start+1,"");
}
}
}
}
}
};