<FrameLayout    android:layout_width="match_parent"    android:layout_height="wrap_content">    <TextView      android:id="@+id/tv"      android:layout_width="match_parent"      android:layout_height="match_parent"      android:layout_marginRight="6dp"      android:background="@null"      android:gravity="right|center_vertical"      android:text="請輸入您想輸入的" />    <EditText      android:id="@+id/et"      android:layout_width="match_parent"      android:layout_height="match_parent"      android:gravity="right|center_vertical" />  </FrameLayout>

 et.addTextChangedListener(new TextWatcher() {      @Override      public void beforeTextChanged(CharSequence charSequence, int i, int i1, int i2) {      }      @Override      public void onTextChanged(CharSequence charSequence, int i, int i1, int i2) {        if (TextUtils.isEmpty(charSequence)) {          tv.setVisibility(View.VISIBLE);        } else {          tv.setVisibility(View.GONE);        }      }      @Override      public void afterTextChanged(Editable editable) {      }    });