Edittext 保持光标在最后

public class LastInputEditText extends EditText {  
  
    public LastInputEditText(Context context, AttributeSet attrs, int defStyle) {  
        super(context, attrs, defStyle);  
    }  
  
    public LastInputEditText(Context context, AttributeSet attrs) {  
        super(context, attrs);  
    }  
  
    public LastInputEditText(Context context) {  
        super(context);  
    }  
      
    @Override  
    protected void onSelectionChanged(int selStart, int selEnd) {  
        super.onSelectionChanged(selStart, selEnd);  
        //保证光标始终在最后面  
        if(selStart==selEnd){//防止不能多选  
            setSelection(getText().length());  
        }  
    }  
}