Question

是否可以将控制属性绑定到具有动态属性名称的模型，例如，存储在另一个模型字段中？我认为我们可以为此目的使用SAPUI5 Expression Binding，但它不起作用：跟踪窗口中的绑定被破坏，表达似乎根本没有被评估。

XML视图

MariaDB []> SELECT * FROM mytab;
+------+------+-----------------+------------------+
| Ref  | Var  | 3SAa combined % | 3SAa combined of |
+------+------+-----------------+------------------+
| AL23 |      | 0.00            | 38.78            |
+------+------+-----------------+------------------+
1 row in set (0.00 sec)

MariaDB []>  SET @table_name = 'mytab';
Query OK, 0 rows affected (0.00 sec)

MariaDB [bernd]>  SET @col_id = 3;
Query OK, 0 rows affected (0.00 sec)

MariaDB []>  SELECT DATABASE() INTO @dbname;
Query OK, 1 row affected (0.00 sec)

MariaDB []>  SELECT SUBSTRING_INDEX(COLUMN_NAME,' ' , 1)  INTO @id_name
    ->  FROM information_schema.columns
    ->   WHERE table_schema = @dbname
    ->    AND TABLE_NAME = @table_name
    ->    AND ORDINAL_POSITION = @col_id;
Query OK, 1 row affected (0.01 sec)

MariaDB []>  SELECT CONCAT('SELECT \'', @id_name, '\' AS Id, ' , GROUP_CONCAT(
    ->      CONCAT( '`',COLUMN_NAME,'`')
    ->      , ' AS `', REPLACE(COLUMN_NAME,CONCAT(@id_name,' ') , '')
    ->      ,'`\n' ), ' FROM ', @table_name) INTO @sql
    ->   FROM information_schema.columns
    ->   WHERE table_schema = @dbname
    ->    AND TABLE_NAME = @table_name
    ->   ORDER BY ORDINAL_POSITION;
Query OK, 1 row affected (0.01 sec)

MariaDB []> PREPARE stmt FROM @sql;
Query OK, 0 rows affected (0.00 sec)
Statement prepared

MariaDB []> EXECUTE stmt;
+------+------+------+------------+-------------+
| Id   | Ref  | Var  | combined % | combined of |
+------+------+------+------------+-------------+
| 3SAa | AL23 |      | 0.00       | 38.78       |
+------+------+------+------------+-------------+
1 row in set (0.00 sec)

MariaDB []> DEALLOCATE PREPARE stmt;
Query OK, 0 rows affected (0.00 sec)

控制器

<TextArea value="{= ${StackOverflow>/bindTextAreaTo} }" />

Answer 1

不，这是目前无法实现的。

但是，您想要做的事情有一个简单的解决方法（见下文）。基本上，您创建一个视图模型并在模型上设置一些布尔值。然后在表达式绑定中使用此标志来“动态”定义应使用的模型的属性...

<强> xmlView中

<TextArea value="{= ${view>/ask} ? ${StackOverflow>/question} : ${StackOverflow>/comment} }" />

<强>控制器

var oModel = this.getView().getModel("StackOverflow");
oModel.setProperty("/question", "");
oModel.setProperty("/comment", "");
//...

var oViewModel = new sap.ui.model.json.JSONModel();
this.getView().setModel(oViewModel, "view);
//...

oViewModel.setProperty("/ask", bAsk);

SAPUI5表达式绑定

1 个答案: