---
title: "FilterModel[T]"
---
import XRef from "../../../../components/XRef.astro";
import Signature from "../../../../components/Signature.astro";

```python
from slint import FilterModel
```

FilterModel is a <XRef to="Model" /> that provides the rows of a source model for
which a filter function returns true.

The FilterModel follows the changes of the source model.
Setting a row sets the corresponding row of the source model.

```python
numbers = slint.ListModel([1, 2, 3, 4])
even_numbers = slint.FilterModel(numbers, lambda n: n % 2 == 0)
assert list(even_numbers) == [2, 4]
```

Alternatively, subclass FilterModel and implement `filter_row`.
Call `reset` when the result of the filter changes for reasons other than
a change of the source model:

```python
class Search(slint.FilterModel[str]):
    def __init__(self, source: slint.Model[str]) -> None:
        self.text = ""
        super().__init__(source)

    def filter_row(self, row_data: str) -> bool:
        return self.text in row_data

search = Search(slint.ListModel(["Hans", "Max", "Roman"]))
search.text = "Max"
search.reset()
```

**Bases:** _WritableAdapterModel&#91;T&#93;

## Properties

### source_model

<Signature symbol="slint.models.FilterModel.source_model">source_model</Signature>

## Methods

### filter_row

<Signature symbol="slint.models.FilterModel.filter_row">filter_row(row_data: T) -&gt; <XRef to="bool" plain /></Signature>

Returns true if `row_data`, a row of the source model, is a row of this model.
Re-implement this method in a sub-class that doesn't pass a filter function
to the constructor.

### reset

<Signature symbol="slint.models.FilterModel.reset">reset() -&gt; <XRef to="None" plain /></Signature>

Applies the filter to all rows of the source model again.
Call this when the result of the filter changes for reasons other than
a change of the source model.

### unfiltered_row

<Signature symbol="slint.models.FilterModel.unfiltered_row">unfiltered_row(row: <XRef to="int" plain />) -&gt; <XRef to="int" plain /></Signature>

Returns the index of the row of the source model that is `row` in this model.
Raises IndexError if `row` is out of range.

### notify_row_changed

<Signature symbol="slint.models.Model.notify_row_changed">notify_row_changed(row: <XRef to="int" plain />) -&gt; <XRef to="None" plain /></Signature>

Call this method from a sub-class to notify the views that a row has changed.

### notify_row_removed

<Signature symbol="slint.models.Model.notify_row_removed">notify_row_removed(row: <XRef to="int" plain />, count: <XRef to="int" plain />) -&gt; <XRef to="None" plain /></Signature>

Call this method from a sub-class to notify the views that
`count` rows have been removed starting at `row`.

### notify_row_added

<Signature symbol="slint.models.Model.notify_row_added">notify_row_added(row: <XRef to="int" plain />, count: <XRef to="int" plain />) -&gt; <XRef to="None" plain /></Signature>

Call this method from a sub-class to notify the views that
`count` rows have been added starting at `row`.

### set_row_data

<Signature symbol="slint.models._WritableAdapterModel.set_row_data">set_row_data(row: <XRef to="int" plain />, value: T) -&gt; <XRef to="None" plain /></Signature>

Sets the row of the source model that corresponds to `row`.
Raises IndexError if `row` is out of range.

### row_count

<Signature symbol="slint.models._AdapterModel.row_count">row_count() -&gt; <XRef to="int" plain /></Signature>

### row_data

<Signature symbol="slint.models._AdapterModel.row_data">row_data(row: <XRef to="int" plain />) -&gt; T | None</Signature>

### push_row

<Signature symbol="slint.models.Model.push_row">push_row(value: T) -&gt; <XRef to="None" plain /></Signature>

Add a new row to the model with the provided value.
The default implementation calls `insert_row` with the row count.

### remove_row

<Signature symbol="slint.models.Model.remove_row">remove_row(row: <XRef to="int" plain />) -&gt; <XRef to="None" plain /></Signature>

Remove the row at the given index.
Raises an exception when the model rejects the modification.
The default implementation raises NotImplementedError. A model that
supports removing rows should also call `notify_row_removed`.

### insert_row

<Signature symbol="slint.models.Model.insert_row">insert_row(row: <XRef to="int" plain />, value: T) -&gt; <XRef to="None" plain /></Signature>

Insert a new row at the given index.
Raises an exception when the model rejects the modification.
The default implementation raises NotImplementedError. A model that
supports inserting rows should also call `notify_row_added`.