Fields are used to define what a Model is. They aren't instantiated directly - instead, when we create a class - * that extends {@link Ext.data.Model}, it will automatically create a Field instance for each field configured in a - * {@link Ext.data.Model Model}. For example, we might set up a model like this:
- * -
-Ext.define('User', {
- extend: 'Ext.data.Model',
- fields: [
- 'name', 'email',
- {name: 'age', type: 'int'},
- {name: 'gender', type: 'string', defaultValue: 'Unknown'}
- ]
-});
-Four fields will have been created for the User Model - name, email, age and gender. Note that we specified a - * couple of different formats here; if we only pass in the string name of the field (as with name and email), the - * field is set up with the 'auto' type. It's as if we'd done this instead:
- * -
-Ext.define('User', {
- extend: 'Ext.data.Model',
- fields: [
- {name: 'name', type: 'auto'},
- {name: 'email', type: 'auto'},
- {name: 'age', type: 'int'},
- {name: 'gender', type: 'string', defaultValue: 'Unknown'}
- ]
-});
-Types and conversion
- * - *The {@link #type} is important - it's used to automatically convert data passed to the field into the correct - * format. In our example above, the name and email fields used the 'auto' type and will just accept anything that is - * passed into them. The 'age' field had an 'int' type however, so if we passed 25.4 this would be rounded to 25.
- * - *Sometimes a simple type isn't enough, or we want to perform some processing when we load a Field's data. We can - * do this using a {@link #convert} function. Here, we're going to create a new field based on another:
- * -
-Ext.define('User', {
- extend: 'Ext.data.Model',
- fields: [
- 'name', 'email',
- {name: 'age', type: 'int'},
- {name: 'gender', type: 'string', defaultValue: 'Unknown'},
-
- {
- name: 'firstName',
- convert: function(value, record) {
- var fullName = record.get('name'),
- splits = fullName.split(" "),
- firstName = splits[0];
-
- return firstName;
- }
- }
- ]
-});
-Now when we create a new User, the firstName is populated automatically based on the name:
- * -
-var ed = Ext.ModelManager.create({name: 'Ed Spencer'}, 'User');
-
-console.log(ed.get('firstName')); //logs 'Ed', based on our convert function
-In fact, if we log out all of the data inside ed, we'll see this:
- * -
-console.log(ed.data);
-
-//outputs this:
-{
- age: 0,
- email: "",
- firstName: "Ed",
- gender: "Unknown",
- name: "Ed Spencer"
-}
-The age field has been given a default of zero because we made it an int type. As an auto field, email has - * defaulted to an empty string. When we registered the User model we set gender's {@link #defaultValue} to 'Unknown' - * so we see that now. Let's correct that and satisfy ourselves that the types work as we expect:
- * -
-ed.set('gender', 'Male');
-ed.get('gender'); //returns 'Male'
-
-ed.set('age', 25.4);
-ed.get('age'); //returns 25 - we wanted an int, not a float, so no decimal places allowed
-dataIndex property in column definition objects passed to {@link Ext.grid.property.HeaderContainer}.
- * Note: In the simplest case, if no properties other than name are required, a field
- * definition may consist of just a String for the field name.
{@link Ext.data.Field#convert convert}
- * has not been specified. This may be specified as a string value. Possible values are
- * This may also be specified by referencing a member of the {@link Ext.data.Types} class.
- *Developers may create their own application-specific data types by defining new members of the - * {@link Ext.data.Types} class.
+ * @cfg {String/Object} type + * + * The data type for automatic conversion from received data to the *stored* value if + * `{@link Ext.data.Field#convert convert}` has not been specified. This may be specified as a string value. + * Possible values are + * + * - auto (Default, implies no conversion) + * - string + * - int + * - float + * - boolean + * - date + * + * This may also be specified by referencing a member of the {@link Ext.data.Types} class. + * + * Developers may create their own application-specific data types by defining new members of the {@link + * Ext.data.Types} class. */ /** * @cfg {Function} convert - * (Optional) A function which converts the value provided by the Reader into an object that will be stored - * in the Model. It is passed the following parameters:{@link Ext.data.Field#defaultValue defaultValue}.
-// example of convert function
-function fullName(v, record){
- return record.name.last + ', ' + record.name.first;
-}
-
-function location(v, record){
- return !record.city ? '' : (record.city + ', ' + record.state);
-}
-
-Ext.define('Dude', {
- extend: 'Ext.data.Model',
- fields: [
- {name: 'fullname', convert: fullName},
- {name: 'firstname', mapping: 'name.first'},
- {name: 'lastname', mapping: 'name.last'},
- {name: 'city', defaultValue: 'homeless'},
- 'state',
- {name: 'location', convert: location}
- ]
-});
-
-// create the data store
-var store = new Ext.data.Store({
- reader: {
- type: 'json',
- model: 'Dude',
- idProperty: 'key',
- root: 'daRoot',
- totalProperty: 'total'
- }
-});
-
-var myData = [
- { key: 1,
- name: { first: 'Fat', last: 'Albert' }
- // notice no city, state provided in data object
- },
- { key: 2,
- name: { first: 'Barney', last: 'Rubble' },
- city: 'Bedrock', state: 'Stoneridge'
- },
- { key: 3,
- name: { first: 'Cliff', last: 'Claven' },
- city: 'Boston', state: 'MA'
- }
-];
- * (Optional) Used when converting received data into a Date when the {@link #type} is specified as "date".
A format string for the {@link Ext.Date#parse Ext.Date.parse} function, or "timestamp" if the - * value provided by the Reader is a UNIX timestamp, or "time" if the value provided by the Reader is a - * javascript millisecond timestamp. See {@link Ext.Date}
+ * + * Used when converting received data into a Date when the {@link #type} is specified as `"date"`. + * + * A format string for the {@link Ext.Date#parse Ext.Date.parse} function, or "timestamp" if the value provided by + * the Reader is a UNIX timestamp, or "time" if the value provided by the Reader is a javascript millisecond + * timestamp. See {@link Ext.Date}. */ dateFormat: null, /** * @cfg {Boolean} useNull - *(Optional) Use when converting received data into a Number type (either int or float). If the value cannot be parsed,
- * null will be used if useNull is true, otherwise the value will be 0. Defaults to false
+ *
+ * Use when converting received data into a Number type (either int or float). If the value cannot be
+ * parsed, null will be used if useNull is true, otherwise the value will be 0. Defaults to false.
*/
useNull: false,
/**
- * @cfg {Mixed} defaultValue
- * (Optional) The default value used when a Model is being created by a {@link Ext.data.reader.Reader Reader}
- * when the item referenced by the {@link Ext.data.Field#mapping mapping} does not exist in the data
- * object (i.e. undefined). (defaults to "")
+ * @cfg {Object} defaultValue
+ *
+ * The default value used **when a Model is being created by a {@link Ext.data.reader.Reader Reader}**
+ * when the item referenced by the `{@link Ext.data.Field#mapping mapping}` does not exist in the data object
+ * (i.e. undefined). Defaults to "".
*/
defaultValue: "",
+
/**
* @cfg {String/Number} mapping
- *
(Optional) A path expression for use by the {@link Ext.data.reader.Reader} implementation - * that is creating the {@link Ext.data.Model Model} to extract the Field value from the data object. - * If the path expression is the same as the field name, the mapping may be omitted.
- *The form of the mapping expression depends on the Reader being used.
- *If a more complex value extraction strategy is required, then configure the Field with a {@link #convert} + * + * (Optional) A path expression for use by the {@link Ext.data.reader.Reader} implementation that is creating the + * {@link Ext.data.Model Model} to extract the Field value from the data object. If the path expression is the same + * as the field name, the mapping may be omitted. + * + * The form of the mapping expression depends on the Reader being used. + * + * - {@link Ext.data.reader.Json} + * + * The mapping is a string containing the javascript expression to reference the data from an element of the data + * item's {@link Ext.data.reader.Json#root root} Array. Defaults to the field name. + * + * - {@link Ext.data.reader.Xml} + * + * The mapping is an {@link Ext.DomQuery} path to the data item relative to the DOM element that represents the + * {@link Ext.data.reader.Xml#record record}. Defaults to the field name. + * + * - {@link Ext.data.reader.Array} + * + * The mapping is a number indicating the Array index of the field's value. Defaults to the field specification's + * Array position. + * + * If a more complex value extraction strategy is required, then configure the Field with a {@link #convert} * function. This is passed the whole row object, and may interrogate it in whatever way is necessary in order to - * return the desired data.
+ * return the desired data. */ mapping: null, + /** * @cfg {Function} sortType - * (Optional) A function which converts a Field's value to a comparable value in order to ensure - * correct sort ordering. Predefined functions are provided in {@link Ext.data.SortTypes}. A custom - * sort example:
-// current sort after sort we want
-// +-+------+ +-+------+
-// |1|First | |1|First |
-// |2|Last | |3|Second|
-// |3|Second| |2|Last |
-// +-+------+ +-+------+
-
-sortType: function(value) {
- switch (value.toLowerCase()) // native toLowerCase():
- {
- case 'first': return 1;
- case 'second': return 2;
- default: return 3;
- }
-}
- * "ASC" or "DESC"). Defaults to
- * "ASC".
+ *
+ * Initial direction to sort (`"ASC"` or `"DESC"`). Defaults to `"ASC"`.
*/
sortDir : "ASC",
+
/**
* @cfg {Boolean} allowBlank
* @private
- * (Optional) Used for validating a {@link Ext.data.Model model}, defaults to true.
- * An empty value here will cause {@link Ext.data.Model}.{@link Ext.data.Model#isValid isValid}
- * to evaluate to false.
+ *
+ * Used for validating a {@link Ext.data.Model model}. Defaults to true. An empty value here will cause
+ * {@link Ext.data.Model}.{@link Ext.data.Model#isValid isValid} to evaluate to false.
*/
allowBlank : true,
-
+
/**
* @cfg {Boolean} persist
- * False to exclude this field from the {@link Ext.data.Model#modified} fields in a model. This
- * will also exclude the field from being written using a {@link Ext.data.writer.Writer}. This option
- * is useful when model fields are used to keep state on the client but do not need to be persisted
- * to the server. Defaults to true.
+ *
+ * False to exclude this field from the {@link Ext.data.Model#modified} fields in a model. This will also exclude
+ * the field from being written using a {@link Ext.data.writer.Writer}. This option is useful when model fields are
+ * used to keep state on the client but do not need to be persisted to the server. Defaults to true.
*/
persist: true
});