Android EditText 在光标处插入，删除内容（例如可用于表情文字输入控件）

1.获取光标位置 [java] int index = editText.getSelectionStart();  2.在光标处插入字符 [java] int index = editText.getSelectionStart();  Editable editable = editText.getText();  editable.insert(index, "aaaa");  3.删除光标前字符 [java] int index = editText.getSelectionStart();  Editable editable = editText.getText();  editable.delete(index-1, index);