diff options
Diffstat (limited to 'doc/src/declarative/qdeclarativemodels.qdoc')
-rw-r--r-- | doc/src/declarative/qdeclarativemodels.qdoc | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/doc/src/declarative/qdeclarativemodels.qdoc b/doc/src/declarative/qdeclarativemodels.qdoc index b44e6f2..a2f4d3a 100644 --- a/doc/src/declarative/qdeclarativemodels.qdoc +++ b/doc/src/declarative/qdeclarativemodels.qdoc @@ -429,4 +429,77 @@ Rectangle { } \endcode +\section1 Accessing Views and Models from Delegates + +You can access the view for which a delegate is used, and its +properties, by using ListView.view in a delegate on a ListView, or +GridView.view in a delegate on a GridView, etc. In particular, you can +access the model and its properties by using ListView.view.model. + +This is useful when you want to use the same delegate for a number of +views, for example, but you want decorations or other features to be +different for each view, and you would like these different settings to +be properties of each of the views. Similarly, it might be of interest +to access or show some properties of the model. + +In the following example, the delegate shows the property \e{language} +of the model, and the color of one of the fields depends on the +property \e{fruit_color} of the view. + +\code +Rectangle { + width: 200; height: 200 + + ListModel { + id: fruitModel + property string language: "en" + ListElement { + name: "Apple" + cost: 2.45 + } + ListElement { + name: "Orange" + cost: 3.25 + } + ListElement { + name: "Banana" + cost: 1.95 + } + } + + Component { + id: fruitDelegate + Row { + Text { text: " Fruit: " + name; color: ListView.view.fruit_color } + Text { text: " Cost: $" + cost } + Text { text: " Language: " + ListView.view.model.language } + } + } + + ListView { + property color fruit_color: "green" + model: fruitModel + delegate: fruitDelegate + anchors.fill: parent + } +} +\endcode + +Another important case is when some action (e.g. mouse click) in the +delegate should update data in the model. In this case you can define +a function in the model, e.g.: + +\code + setData(int row, const QString & field_name, QVariant new_value), +\endcode + +...and call it from the delegate using: + +\code + ListView.view.model.setData(index, field, value) +\endcode + +...assuming that \e{field} holds the name of the field which should be +updated, and that \e{value} holds the new value. + */ |