If you do not have a value to return, return an invalid qvariant instead of returning 0. For someone coming from the cocoa world, understanding how qtreeview and qabstractitemmodel work can be quite hard. Displayrole this method is abstract and should be reimplemented in any subclass. Documentation contributions included herein are the s of their respective owners. History in a web browser has a number of challenges that make it a good demonstration of qts modelview. It is difficult to define an api that will stand the.
To obtain a model index that refers to an existing item in a model, call. The qabstractlistmodel class provides an abstract model that can be subclassed to create onedimensional list models qabstractlistmodel provides a standard interface for models that represent their data as a simple nonhierarchical sequence of items. Ive got a question about implementation of a standart tree model for treeview. Youre right, i was missing the fact the index points to the column i double click on.
The history is used in the url completer, the history dialog, the history menu and lastly by webkit itself for determining if you have been somewhere before. Qfilesystemmodelqabstractitemmodel qabstractitemmodel. Qabstractitemmodel class defines the standard interface that item models must use to be able to interoperate with other components in the modelview architecture. Qabstractitemmodels in qml views the missing pieces. Using qabstractitemmodel with cascades on bb10 kdab. If you do not make use of the hierarchy, then the model is a simple table of rows and columns. Qabstractitemmodel vs qstandarditemmodel invalidmagics blog. Changes an item in the string list, but only if the following conditions are met. The qabstractitemmodel interface provides two things. It allows you to easily separate the logical part of your application from the ui. Each item has a unique index specified by a qmodelindex.
The usage of a custom listitemcomponent in this example brings us to a specific in abstractitemmodel. Qabstractitemview class is the base class for every standard view that uses a qabstractitemmodel. I will probably implement these generic lists in the next. How to retrieve a qmodelindex for a custom data object. A question regarding qabstractitemmodel used in a qtreeview and its access from a button slot. The structure of the model is defined by how you implement the rowcount, columncount, index and parent methods. Instead, you should subclass it to create new models. The qabstractitemmodel class provides the abstract interface for item model classes. I guess this is the change i have been long waiting for. I do not get what to you mean how to load some number of items from table because data may be shown from very different tables. Ive took a look at example, that comes with pyqt4, but in that example they retrieve data from a text file, where tree structure is marked by tabs. Ive implemented index like ive been told in the above answer, and got a tree with infinite recursion. So, one of columns in table keeps name of the table with children. Navigating a qabstractitemmodel tree in a qml view.
The database contains a table with a list of people, which has four columns. Qabstractitemmodel with qtreeview and accessing through. Example of showing different context menu for items in a. The qabstractitemmodel class defines the standard interface that item models must use to be able to interoperate with other components in the modelview architecture. In the index method you should return createindexrow, column if row and column are valid, and qmodelindex otherwise.
Example of showing different context menu for items in a qtreewidget with qitemdelegate gist. Qabstractlistmodel provides a standard interface for models that represent their data as a simple nonhierarchical sequence of items. Qabstractitemmodelindex with the required row and column values, and. When reimplementing insertrows in a subclass, you must call this function before inserting data into the models underlying data store the parent index corresponds to the parent into which the new rows are inserted. Qabstractlistmodel class provides an abstract model that can be subclassed to create onedimensional list models pyside. It is not possible to directly display a treeview on a hierarchical model. See the model subclassing reference for more information the complete source code for this example is available in. Solved qabstractitemmodeldatachanged question qt forum.
For grid or tree models, the qmodelindex might hold more interest to us, but for a simple list like ours we are only interested in the row index, and the requested role. Qml views are automatically updated when the model changes. Returns the data stored under the given role for the item referred to by the index. The model function returns the model that the index references as a. Remember the model must follow the standard rules for model changes and notify the view when the model has changed by using qabstractitemmodeldatachanged, qabstractitemmodelbegininsertrows, and so on. Since the model provides a more specialized interface than pyside. You can attach additional data to an index using the 3rd argument of createindex this is totally wrong. The qabstractitemmodel data is accessed via datafunction. The qabstractproxymodel class provides a base class for proxy item models that can do sorting, filtering or other data processing tasks. Qabstractitemmodel with qtreeview and accessing through indexing qabstractitemmodel with qtreeview and accessing through indexing. The documentation provided herein is licensed under the terms of the gnu free documentation license version 1. A small example to work with the database in qml qt. While the concept of an item model for a tree view also exists in cocoa, the way qabstractitemmodel works is quite different from nsoutlinedatasources the biggest difference between the two models is in the. Qabstractitemview is an abstract class and cannot itself be instantiated.
I got the row header working and changed the font for the hole qtableview i marked the changes with new. For example, as shown in the diagram, we insert three columns before column 4, so first is 4 and last is 6 begininsertcolumnsparent, 4, 6 this inserts the three new columns as columns 4, 5, and 6. Qabstractitemmodel vs qstandarditemmodel september 20, 2010 by invalidmagic lately i started working on a torrent implementation for the evopedia project 1. I was already aware of the second problem you highlighted the fact one doubleclick can change rows other than the one ive doubleclicked on, this is still work in progress. While bbcascadesdatamodeldataindexpath returns all data of the item at this indexpath in one go, qabstractitemmodeldataindex, role returns only the data at this index for the specific role. In addition your models can interact with a sql database and be processed through some resources heavy filters while still. For the most basic needs, for example integrating a qml view into a c++ project, the. Specify the first and last column numbers for the span of columns you want to insert into an item in a model. The qabstractitemview class provides the basic functionality for item view classes. Since the model provides a more specialized interface than. Qabstractitemmodel class provides the abstract interface for item model classes the pyside.
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