slint/api/cpp/include/slint_models.h
2025-05-30 15:47:13 +02:00

1152 lines
39 KiB
C++

// Copyright © SixtyFPS GmbH <info@slint.dev>
// SPDX-License-Identifier: GPL-3.0-only OR LicenseRef-Slint-Royalty-free-2.0 OR LicenseRef-Slint-Software-3.0
#pragma once
#include "slint_item_tree.h"
#include <algorithm>
#include <functional>
#include <memory>
#include <optional>
namespace slint {
namespace private_api {
struct ModelChangeListener
{
virtual ~ModelChangeListener() = default;
virtual void row_added(size_t index, size_t count) = 0;
virtual void row_removed(size_t index, size_t count) = 0;
virtual void row_changed(size_t index) = 0;
virtual void reset() = 0;
};
using ModelPeer = std::weak_ptr<ModelChangeListener>;
template<typename M>
auto access_array_index(const std::shared_ptr<M> &model, std::ptrdiff_t index)
{
if (!model || index < 0) {
return decltype(*model->row_data_tracked(index)) {};
} else if (const auto v = model->row_data_tracked(index)) {
return *v;
} else {
return decltype(*v) {};
}
}
template<typename M>
long int model_length(const std::shared_ptr<M> &model)
{
if (!model) {
return 0;
} else {
model->track_row_count_changes();
return model->row_count();
}
}
} // namespace private_api
/// \rst
/// A Model is providing Data for Slint |Models|_ or |ListView|_ elements of the
/// :code:`.slint` language
/// \endrst
///
/// This is typically used in a `std::shared_ptr<slint::Model>`.
/// Model is an abstract class and you can derive from it to provide your own data model,
/// or use one of the provided models such as `slint::VectorModel`
///
/// An implementation of the Model can provide data to slint by re-implementing the `row_count` and
/// `row_data` functions. It is the responsibility of the Model implementation to call the
/// `Model::notify_row_changed()`, `Model::notify_row_added()`, `Model::notify_row_removed()`, or
/// `Model::notify_reset()` functions when the underlying data changes.
///
/// Note that the Model is not thread-safe. All Model operations need to be done in the main thread.
/// If you need to update the model data from another thread, use the
/// `slint::invoke_from_event_loop()` function to send the data to the main thread and update the
/// model.
template<typename ModelData>
class Model
{
public:
virtual ~Model() = default;
Model() = default;
Model(const Model &) = delete;
Model &operator=(const Model &) = delete;
/// The amount of row in the model
virtual size_t row_count() const = 0;
/// Returns the data for a particular row. This function should be called with `row <
/// row_count()`.
virtual std::optional<ModelData> row_data(size_t i) const = 0;
/// Sets the data for a particular row.
///
/// This function should only be called with `row < row_count()`.
///
/// If the model cannot support data changes, then it is ok to do nothing.
/// The default implementation will print a warning to stderr.
///
/// If the model can update the data, it should also call `row_changed`
virtual void set_row_data(size_t, const ModelData &)
{
#ifndef SLINT_FEATURE_FREESTANDING
std::cerr << "Model::set_row_data was called on a read-only model" << std::endl;
#endif
};
/// \private
/// Internal function called by the view to register itself
void attach_peer(private_api::ModelPeer p) { peers.push_back(std::move(p)); }
/// \private
/// Internal function called from within bindings to register with the currently
/// evaluating dependency and get notified when this model's row count changes.
void track_row_count_changes() const { model_row_count_dirty_property.get(); }
/// \private
/// Internal function called from within bindings to register with the currently
/// evaluating dependency and get notified when this model's row data changes.
void track_row_data_changes(size_t row) const
{
auto it = std::lower_bound(tracked_rows.begin(), tracked_rows.end(), row);
if (it == tracked_rows.end() || row < *it) {
tracked_rows.insert(it, row);
}
model_row_data_dirty_property.get();
}
/// \private
/// Convenience function that calls `track_row_data_changes` before returning `row_data`
std::optional<ModelData> row_data_tracked(size_t row) const
{
track_row_data_changes(row);
return row_data(row);
}
protected:
/// Notify the views that a specific row was changed
///
/// Your model implementation should call this function after the data of a row changes.
void notify_row_changed(size_t row)
{
private_api::assert_main_thread();
if (std::binary_search(tracked_rows.begin(), tracked_rows.end(), row)) {
model_row_data_dirty_property.mark_dirty();
}
for_each_peers([=](auto peer) { peer->row_changed(row); });
}
/// Notify the views that rows were added
///
/// Your model implementation should call this function after the row were added.
void notify_row_added(size_t index, size_t count)
{
private_api::assert_main_thread();
model_row_count_dirty_property.mark_dirty();
tracked_rows.clear();
model_row_data_dirty_property.mark_dirty();
for_each_peers([=](auto peer) { peer->row_added(index, count); });
}
/// Notify the views that rows were removed
///
/// Your model implementation should call this function after the row were removed.
void notify_row_removed(size_t index, size_t count)
{
private_api::assert_main_thread();
model_row_count_dirty_property.mark_dirty();
tracked_rows.clear();
model_row_data_dirty_property.mark_dirty();
for_each_peers([=](auto peer) { peer->row_removed(index, count); });
}
/// Notify the views that the model has been changed and that everything needs to be reloaded
///
/// Your model implementation should call this function after the model has been changed.
void notify_reset()
{
private_api::assert_main_thread();
model_row_count_dirty_property.mark_dirty();
tracked_rows.clear();
model_row_data_dirty_property.mark_dirty();
for_each_peers([=](auto peer) { peer->reset(); });
}
/// \deprecated
[[deprecated("Renamed to notify_row_changed")]] void row_changed(size_t row)
{
notify_row_changed(row);
}
/// \deprecated
[[deprecated("Renamed to notify_row_added")]] void row_added(size_t index, size_t count)
{
notify_row_added(index, count);
}
/// \deprecated
[[deprecated("Renamed to notify_row_removed")]] void row_removed(size_t index, size_t count)
{
notify_row_removed(index, count);
}
/// \deprecated
[[deprecated("Renamed to notify_reset")]] void reset() { notify_reset(); }
private:
template<typename F>
void for_each_peers(const F &f)
{
peers.erase(std::remove_if(peers.begin(), peers.end(),
[&](const auto &p) {
if (auto pp = p.lock()) {
f(pp);
return false;
}
return true;
}),
peers.end());
}
std::vector<private_api::ModelPeer> peers;
private_api::Property<bool> model_row_count_dirty_property;
private_api::Property<bool> model_row_data_dirty_property;
mutable std::vector<size_t> tracked_rows;
};
namespace private_api {
/// A Model backed by a std::array of constant size
/// \private
template<int Count, typename ModelData>
class ArrayModel : public Model<ModelData>
{
std::array<ModelData, Count> data;
public:
/// Constructs a new ArrayModel by forwarding \a to the std::array constructor.
template<typename... A>
ArrayModel(A &&...a) : data { std::forward<A>(a)... }
{
}
size_t row_count() const override { return Count; }
std::optional<ModelData> row_data(size_t i) const override
{
if (i >= row_count())
return {};
return data[i];
}
void set_row_data(size_t i, const ModelData &value) override
{
if (i < row_count()) {
data[i] = value;
this->notify_row_changed(i);
}
}
};
// Specialize for the empty array. We can't have a Model<void>, but `int` will work for our purpose
template<>
class ArrayModel<0, void> : public Model<int>
{
public:
size_t row_count() const override { return 0; }
std::optional<int> row_data(size_t) const override { return {}; }
};
/// Model to be used when we just want to repeat without data.
struct UIntModel : Model<int>
{
/// Constructs a new IntModel with \a d rows.
UIntModel(uint32_t d) : data(d) { }
/// \private
uint32_t data;
/// \copydoc Model::row_count
size_t row_count() const override { return data; }
std::optional<int> row_data(size_t value) const override
{
if (value >= row_count())
return {};
return static_cast<int>(value);
}
};
} // namespace private_api
/// A Model backed by a SharedVector
template<typename ModelData>
class VectorModel : public Model<ModelData>
{
std::vector<ModelData> data;
public:
/// Constructs a new empty VectorModel.
VectorModel() = default;
/// Constructs a new VectorModel from \a array.
VectorModel(std::vector<ModelData> array) : data(std::move(array)) { }
size_t row_count() const override { return data.size(); }
std::optional<ModelData> row_data(size_t i) const override
{
if (i >= row_count())
return {};
return std::optional<ModelData> { data[i] };
}
void set_row_data(size_t i, const ModelData &value) override
{
if (i < row_count()) {
data[i] = value;
this->notify_row_changed(i);
}
}
/// Append a new row with the given value
void push_back(const ModelData &value)
{
data.push_back(value);
this->notify_row_added(data.size() - 1, 1);
}
/// Remove the row at the given index from the model
void erase(size_t index)
{
data.erase(data.begin() + index);
this->notify_row_removed(index, 1);
}
/// Inserts the given value as a new row at the specified index
void insert(size_t index, const ModelData &value)
{
data.insert(data.begin() + index, value);
this->notify_row_added(index, 1);
}
/// Erases all rows from the VectorModel.
void clear()
{
if (!data.empty()) {
data.clear();
this->notify_reset();
}
}
/// Replaces the underlying VectorModel's vector with \a array.
void set_vector(std::vector<ModelData> array)
{
data = std::move(array);
this->notify_reset();
}
};
template<typename ModelData>
class FilterModel;
namespace private_api {
template<typename ModelData>
struct FilterModelInner : private_api::ModelChangeListener
{
FilterModelInner(std::shared_ptr<slint::Model<ModelData>> source_model,
std::function<bool(const ModelData &)> filter_fn,
slint::FilterModel<ModelData> &target_model)
: source_model(source_model), filter_fn(filter_fn), target_model(target_model)
{
}
void row_added(size_t index, size_t count) override
{
if (filtered_rows_dirty) {
reset();
return;
}
if (count == 0) {
return;
}
std::vector<size_t> added_accepted_rows;
for (auto i = index; i < index + count; ++i) {
if (auto data = source_model->row_data(i)) {
if (filter_fn(*data)) {
added_accepted_rows.push_back(i);
}
}
}
if (added_accepted_rows.empty()) {
return;
}
auto insertion_point = std::lower_bound(accepted_rows.begin(), accepted_rows.end(), index);
insertion_point = accepted_rows.insert(insertion_point, added_accepted_rows.begin(),
added_accepted_rows.end());
for (auto it = insertion_point + added_accepted_rows.size(); it != accepted_rows.end();
++it)
(*it) += count;
target_model.notify_row_added(insertion_point - accepted_rows.begin(),
added_accepted_rows.size());
}
void row_changed(size_t index) override
{
if (filtered_rows_dirty) {
reset();
return;
}
auto existing_row = std::lower_bound(accepted_rows.begin(), accepted_rows.end(), index);
auto existing_row_index = std::distance(accepted_rows.begin(), existing_row);
bool is_contained = existing_row != accepted_rows.end() && *existing_row == index;
auto accepted_updated_row = filter_fn(*source_model->row_data(index));
if (is_contained && accepted_updated_row) {
target_model.notify_row_changed(existing_row_index);
} else if (!is_contained && accepted_updated_row) {
accepted_rows.insert(existing_row, index);
target_model.notify_row_added(existing_row_index, 1);
} else if (is_contained && !accepted_updated_row) {
accepted_rows.erase(existing_row);
target_model.notify_row_removed(existing_row_index, 1);
}
}
void row_removed(size_t index, size_t count) override
{
if (filtered_rows_dirty) {
reset();
return;
}
auto mapped_row_start = std::lower_bound(accepted_rows.begin(), accepted_rows.end(), index);
auto mapped_row_end =
std::lower_bound(accepted_rows.begin(), accepted_rows.end(), index + count);
auto mapped_removed_len = std::distance(mapped_row_start, mapped_row_end);
auto mapped_removed_index =
(mapped_row_start != accepted_rows.end() && *mapped_row_start == index)
? std::optional<int>(mapped_row_start - accepted_rows.begin())
: std::nullopt;
auto it = accepted_rows.erase(mapped_row_start, mapped_row_end);
for (; it != accepted_rows.end(); ++it) {
*it -= count;
}
if (mapped_removed_index) {
target_model.notify_row_removed(*mapped_removed_index, mapped_removed_len);
}
}
void reset() override
{
filtered_rows_dirty = true;
update_mapping();
target_model.notify_reset();
}
void update_mapping()
{
if (!filtered_rows_dirty) {
return;
}
accepted_rows.clear();
for (size_t i = 0, count = source_model->row_count(); i < count; ++i) {
if (auto data = source_model->row_data(i)) {
if (filter_fn(*data)) {
accepted_rows.push_back(i);
}
}
}
filtered_rows_dirty = false;
}
bool filtered_rows_dirty = true;
std::shared_ptr<slint::Model<ModelData>> source_model;
std::function<bool(const ModelData &)> filter_fn;
std::vector<size_t> accepted_rows;
slint::FilterModel<ModelData> &target_model;
};
}
/// The FilterModel acts as an adapter model for a given source model by applying a filter
/// function. The filter function is called for each row on the source model and if the
/// filter accepts the row (i.e. returns true), the row is also visible in the FilterModel.
template<typename ModelData>
class FilterModel : public Model<ModelData>
{
friend struct private_api::FilterModelInner<ModelData>;
public:
/// Constructs a new FilterModel that provides a limited view on the \a source_model by applying
/// \a filter_fn on each row. If the provided function returns true, the row is exposed by the
/// FilterModel.
FilterModel(std::shared_ptr<Model<ModelData>> source_model,
std::function<bool(const ModelData &)> filter_fn)
: inner(std::make_shared<private_api::FilterModelInner<ModelData>>(
std::move(source_model), std::move(filter_fn), *this))
{
inner->source_model->attach_peer(inner);
}
size_t row_count() const override
{
inner->update_mapping();
return inner->accepted_rows.size();
}
std::optional<ModelData> row_data(size_t i) const override
{
inner->update_mapping();
if (i >= inner->accepted_rows.size())
return {};
return inner->source_model->row_data(inner->accepted_rows[i]);
}
void set_row_data(size_t i, const ModelData &value) override
{
inner->update_mapping();
inner->source_model->set_row_data(inner->accepted_rows[i], value);
}
/// Re-applies the model's filter function on each row of the source model. Use this if state
/// external to the filter function has changed.
void reset() { inner->reset(); }
/// Given the \a filtered_row index, this function returns the corresponding row index in the
/// source model.
int unfiltered_row(int filtered_row) const
{
inner->update_mapping();
return inner->accepted_rows[filtered_row];
}
/// Returns the source model of this filter model.
std::shared_ptr<Model<ModelData>> source_model() const { return inner->source_model; }
private:
std::shared_ptr<private_api::FilterModelInner<ModelData>> inner;
};
template<typename SourceModelData, typename MappedModelData>
class MapModel;
namespace private_api {
template<typename SourceModelData, typename MappedModelData>
struct MapModelInner : private_api::ModelChangeListener
{
MapModelInner(slint::MapModel<SourceModelData, MappedModelData> &target_model)
: target_model(target_model)
{
}
void row_added(size_t index, size_t count) override
{
target_model.notify_row_added(index, count);
}
void row_changed(size_t index) override { target_model.notify_row_changed(index); }
void row_removed(size_t index, size_t count) override
{
target_model.notify_row_removed(index, count);
}
void reset() override { target_model.notify_reset(); }
slint::MapModel<SourceModelData, MappedModelData> &target_model;
};
}
/// The MapModel acts as an adapter model for a given source model by applying a mapping
/// function. The mapping function is called for each row on the source model and allows
/// transforming the values on the fly. The MapModel has two template parameters: The
/// SourceModelData specifies the data type of the underlying source model, and the
/// MappedModelData the data type of this MapModel. This permits not only changing the
/// values of the underlying source model, but also changing the data type itself. For
/// example a MapModel can be used to adapt a model that provides numbers to be a model
/// that exposes all numbers converted to strings, by calling `std::to_string` on each
/// value given in the mapping lambda expression.
///
/// \code
/// auto source_model = std::make_shared<slint::VectorModel<Person>>(...);
/// auto mapped_model = std::make_shared<slint::MapModel<Person, SharedString>>(
/// source_model, [](const Person &person) {
// return fmt::format("{} {}", person.first, person.last);
// });
/// \endcode
template<typename SourceModelData, typename MappedModelData = SourceModelData>
class MapModel : public Model<MappedModelData>
{
friend struct private_api::MapModelInner<SourceModelData, MappedModelData>;
public:
/// Constructs a new MapModel that provides an altered view on the \a source_model by applying
/// \a map_fn on the data in each row.
MapModel(std::shared_ptr<Model<SourceModelData>> source_model,
std::function<MappedModelData(const SourceModelData &)> map_fn)
: inner(std::make_shared<private_api::MapModelInner<SourceModelData, MappedModelData>>(
*this)),
model(source_model),
map_fn(map_fn)
{
model->attach_peer(inner);
}
size_t row_count() const override { return model->row_count(); }
std::optional<MappedModelData> row_data(size_t i) const override
{
if (auto source_data = model->row_data(i))
return map_fn(*source_data);
else
return {};
}
/// Returns the source model of this filter model.
std::shared_ptr<Model<SourceModelData>> source_model() const { return model; }
/// Re-applies the model's mapping function on each row of the source model. Use this if state
/// external to the mapping function has changed.
void reset() { inner->reset(); }
private:
std::shared_ptr<private_api::MapModelInner<SourceModelData, MappedModelData>> inner;
std::shared_ptr<slint::Model<SourceModelData>> model;
std::function<MappedModelData(const SourceModelData &)> map_fn;
};
template<typename ModelData>
class SortModel;
namespace private_api {
template<typename ModelData>
struct SortModelInner : private_api::ModelChangeListener
{
SortModelInner(std::shared_ptr<slint::Model<ModelData>> source_model,
std::function<bool(const ModelData &, const ModelData &)> comp,
slint::SortModel<ModelData> &target_model)
: source_model(source_model), comp(comp), target_model(target_model)
{
}
void row_added(size_t first_inserted_row, size_t count) override
{
if (sorted_rows_dirty) {
reset();
return;
}
// Adjust the existing sorted row indices to match the updated source model
for (auto &row : sorted_rows) {
if (row >= first_inserted_row)
row += count;
}
for (size_t row = first_inserted_row; row < first_inserted_row + count; ++row) {
auto inserted_value = source_model->row_data(row);
if (!inserted_value)
continue;
auto insertion_point =
std::lower_bound(sorted_rows.begin(), sorted_rows.end(), *inserted_value,
[this](size_t sorted_row, const ModelData &inserted_value) {
auto sorted_elem = source_model->row_data(sorted_row);
return sorted_elem && comp(*sorted_elem, inserted_value);
});
insertion_point = sorted_rows.insert(insertion_point, row);
target_model.notify_row_added(std::distance(sorted_rows.begin(), insertion_point), 1);
}
}
void row_changed(size_t changed_row) override
{
if (sorted_rows_dirty) {
reset();
return;
}
auto removed_row_it =
sorted_rows.erase(std::find(sorted_rows.begin(), sorted_rows.end(), changed_row));
auto removed_row = std::distance(sorted_rows.begin(), removed_row_it);
auto changed_value = source_model->row_data(changed_row);
if (!changed_value)
return;
auto insertion_point =
std::lower_bound(sorted_rows.begin(), sorted_rows.end(), *changed_value,
[this](size_t sorted_row, const ModelData &changed_value) {
auto sorted_elem = source_model->row_data(sorted_row);
return sorted_elem && comp(*sorted_elem, changed_value);
});
insertion_point = sorted_rows.insert(insertion_point, changed_row);
auto inserted_row = std::distance(sorted_rows.begin(), insertion_point);
if (inserted_row == removed_row) {
target_model.notify_row_changed(removed_row);
} else {
target_model.notify_row_removed(removed_row, 1);
target_model.notify_row_added(inserted_row, 1);
}
}
void row_removed(size_t first_removed_row, size_t count) override
{
if (sorted_rows_dirty) {
reset();
return;
}
std::vector<size_t> removed_rows;
removed_rows.reserve(count);
for (auto it = sorted_rows.begin(); it != sorted_rows.end();) {
if (*it >= first_removed_row) {
if (*it < first_removed_row + count) {
removed_rows.push_back(std::distance(sorted_rows.begin(), it));
it = sorted_rows.erase(it);
continue;
} else {
*it -= count;
}
}
++it;
}
for (auto removed_row : removed_rows) {
target_model.notify_row_removed(removed_row, 1);
}
}
void reset() override
{
sorted_rows_dirty = true;
target_model.notify_reset();
}
void ensure_sorted()
{
if (!sorted_rows_dirty) {
return;
}
sorted_rows.resize(source_model->row_count());
for (size_t i = 0; i < sorted_rows.size(); ++i)
sorted_rows[i] = i;
std::sort(sorted_rows.begin(), sorted_rows.end(), [this](auto lhs_index, auto rhs_index) {
auto lhs_elem = source_model->row_data(lhs_index);
auto rhs_elem = source_model->row_data(rhs_index);
return rhs_elem && lhs_elem && comp(*lhs_elem, *rhs_elem);
});
sorted_rows_dirty = false;
}
std::shared_ptr<slint::Model<ModelData>> source_model;
std::function<bool(const ModelData &, const ModelData &)> comp;
slint::SortModel<ModelData> &target_model;
std::vector<size_t> sorted_rows;
bool sorted_rows_dirty = true;
};
}
/// The SortModel acts as an adapter model for a given source model by sorting all rows
/// with by order provided by the given sorting function. The sorting function is called for
/// pairs of elements of the source model.
///
/// \code
/// auto source_model = std::make_shared<slint::VectorModel<SharedString>>(
// std::vector<SharedString> { "lorem", "ipsum", "dolor" });
/// auto sorted_model = std::make_shared<slint::SortModel<SharedString>>(
/// source_model, [](auto lhs, auto rhs) { return lhs < rhs; }));
/// \endcode
template<typename ModelData>
class SortModel : public Model<ModelData>
{
friend struct private_api::SortModelInner<ModelData>;
public:
/// Constructs a new SortModel that provides a sorted view on the \a source_model by applying
/// the order given by the specified \a comp.
SortModel(std::shared_ptr<Model<ModelData>> source_model,
std::function<bool(const ModelData &, const ModelData &)> comp)
: inner(std::make_shared<private_api::SortModelInner<ModelData>>(std::move(source_model),
std::move(comp), *this))
{
inner->source_model->attach_peer(inner);
}
size_t row_count() const override { return inner->source_model->row_count(); }
std::optional<ModelData> row_data(size_t i) const override
{
inner->ensure_sorted();
return inner->source_model->row_data(inner->sorted_rows[i]);
}
void set_row_data(size_t i, const ModelData &value) override
{
inner->source_model->set_row_data(inner->sorted_rows[i], value);
}
/// Re-applies the model's sort function on each row of the source model. Use this if state
/// external to the sort function has changed.
void reset() { inner->reset(); }
/// Given the \a sorted_row_index, this function returns the corresponding row index in the
/// source model.
int unsorted_row(int sorted_row_index) const
{
inner->ensure_sorted();
return inner->sorted_rows[sorted_row_index];
}
/// Returns the source model of this filter model.
std::shared_ptr<Model<ModelData>> source_model() const { return inner->source_model; }
private:
std::shared_ptr<private_api::SortModelInner<ModelData>> inner;
};
template<typename ModelData>
class ReverseModel;
namespace private_api {
template<typename ModelData>
struct ReverseModelInner : private_api::ModelChangeListener
{
ReverseModelInner(std::shared_ptr<slint::Model<ModelData>> source_model,
slint::ReverseModel<ModelData> &target_model)
: source_model(source_model), target_model(target_model)
{
}
void row_added(size_t first_inserted_row, size_t count) override
{
auto row_count = source_model->row_count();
auto old_row_count = row_count - count;
auto row = old_row_count - first_inserted_row;
target_model.notify_row_added(row, count);
}
void row_changed(size_t changed_row) override
{
target_model.notify_row_changed(source_model->row_count() - 1 - changed_row);
}
void row_removed(size_t first_removed_row, size_t count) override
{
target_model.notify_row_removed(source_model->row_count() - first_removed_row, count);
}
void reset() override { target_model.notify_reset(); }
std::shared_ptr<slint::Model<ModelData>> source_model;
slint::ReverseModel<ModelData> &target_model;
};
}
/// The ReverseModel acts as an adapter model for a given source model by reserving all rows.
/// This means that the first row in the source model is the last row of this model, the second
/// row is the second last, and so on.
///
/// \code
/// auto source_model = std::make_shared<slint::VectorModel<int>>(
// std::vector<int> { 1, 2, 3, 4, 5 });
/// auto reversed_model = std::make_shared<slint::ReverseModel<int>>(source_model);
/// \endcode
template<typename ModelData>
class ReverseModel : public Model<ModelData>
{
friend struct private_api::ReverseModelInner<ModelData>;
public:
/// Constructs a new ReverseModel that provides a reversed view on the \a source_model.
ReverseModel(std::shared_ptr<Model<ModelData>> source_model)
: inner(std::make_shared<private_api::ReverseModelInner<ModelData>>(std::move(source_model),
*this))
{
inner->source_model->attach_peer(inner);
}
size_t row_count() const override { return inner->source_model->row_count(); }
std::optional<ModelData> row_data(size_t i) const override
{
auto count = inner->source_model->row_count();
return inner->source_model->row_data(count - i - 1);
}
void set_row_data(size_t i, const ModelData &value) override
{
auto count = inner->source_model->row_count();
inner->source_model->set_row_data(count - i - 1, value);
}
/// Returns the source model of this reserve model.
std::shared_ptr<Model<ModelData>> source_model() const { return inner->source_model; }
private:
std::shared_ptr<private_api::ReverseModelInner<ModelData>> inner;
};
namespace private_api {
template<typename C, typename ModelData>
class Repeater
{
struct RepeaterInner : ModelChangeListener
{
enum class State { Clean, Dirty };
struct RepeatedInstanceWithState
{
State state = State::Dirty;
std::optional<ComponentHandle<C>> ptr;
};
std::vector<RepeatedInstanceWithState> data;
private_api::Property<bool> is_dirty { true };
std::shared_ptr<Model<ModelData>> model;
void row_added(size_t index, size_t count) override
{
if (index > data.size()) {
// Can happen before ensure_updated was called
return;
}
is_dirty.set(true);
data.resize(data.size() + count);
std::rotate(data.begin() + index, data.end() - count, data.end());
for (std::size_t i = index; i < data.size(); ++i) {
// all the indexes are dirty
data[i].state = State::Dirty;
}
}
void row_changed(size_t index) override
{
if (index >= data.size()) {
return;
}
auto &c = data[index];
if (model && c.ptr) {
if (auto data = model->row_data(index)) {
(*c.ptr)->update_data(index, *data);
}
c.state = State::Clean;
} else {
c.state = State::Dirty;
}
}
void row_removed(size_t index, size_t count) override
{
if (index + count > data.size()) {
// Can happen before ensure_updated was called
return;
}
is_dirty.set(true);
data.erase(data.begin() + index, data.begin() + index + count);
for (std::size_t i = index; i < data.size(); ++i) {
// all the indexes are dirty
data[i].state = State::Dirty;
}
}
void reset() override
{
is_dirty.set(true);
data.clear();
}
};
private_api::Property<std::shared_ptr<Model<ModelData>>> model;
mutable std::shared_ptr<RepeaterInner> inner;
vtable::VRef<private_api::ItemTreeVTable> item_at(int i) const
{
const auto &x = inner->data.at(i);
return { &C::static_vtable, const_cast<C *>(&(**x.ptr)) };
}
public:
template<typename F>
void set_model_binding(F &&binding) const
{
model.set_binding(std::forward<F>(binding));
}
template<typename Parent>
void ensure_updated(const Parent *parent) const
{
if (model.is_dirty()) {
auto old_model = model.get_internal();
auto m = model.get();
if (!inner || old_model != m) {
inner = std::make_shared<RepeaterInner>();
if (m) {
inner->model = m;
m->attach_peer(inner);
}
}
}
if (inner && inner->is_dirty.get()) {
inner->is_dirty.set(false);
if (auto m = model.get()) {
auto count = m->row_count();
inner->data.resize(count);
for (size_t i = 0; i < count; ++i) {
auto &c = inner->data[i];
bool created = false;
if (!c.ptr) {
c.ptr = C::create(parent);
created = true;
}
if (c.state == RepeaterInner::State::Dirty) {
if (auto data = m->row_data(i)) {
(*c.ptr)->update_data(i, *data);
}
}
if (created) {
(*c.ptr)->init();
}
}
} else {
inner->data.clear();
}
} else {
// just do a get() on the model to register dependencies so that, for example, the
// layout property tracker becomes dirty.
model.get();
}
}
template<typename Parent>
void ensure_updated_listview(const Parent *parent,
const private_api::Property<float> *viewport_width,
const private_api::Property<float> *viewport_height,
const private_api::Property<float> *viewport_y,
float listview_width, [[maybe_unused]] float listview_height) const
{
// TODO: the rust code in model.rs try to only allocate as many items as visible items
ensure_updated(parent);
float h = compute_layout_listview(viewport_width, listview_width, viewport_y->get());
viewport_height->set(h);
}
uint64_t visit(TraversalOrder order, private_api::ItemVisitorRefMut visitor) const
{
for (std::size_t i = 0; i < inner->data.size(); ++i) {
auto index = order == TraversalOrder::BackToFront ? i : inner->data.size() - 1 - i;
auto ref = item_at(index);
if (ref.vtable->visit_children_item(ref, -1, order, visitor)
!= std::numeric_limits<uint64_t>::max()) {
return index;
}
}
return std::numeric_limits<uint64_t>::max();
}
vtable::VWeak<private_api::ItemTreeVTable> instance_at(std::size_t i) const
{
if (i >= inner->data.size()) {
return {};
}
const auto &x = inner->data.at(i);
return vtable::VWeak<private_api::ItemTreeVTable> { x.ptr->into_dyn() };
}
private_api::IndexRange index_range() const
{
return private_api::IndexRange { 0, inner->data.size() };
}
std::size_t len() const { return inner ? inner->data.size() : 0; }
float compute_layout_listview(const private_api::Property<float> *viewport_width,
float listview_width, float viewport_y) const
{
float offset = viewport_y;
auto vp_width = listview_width;
if (!inner)
return offset;
for (auto &x : inner->data) {
vp_width = std::max(vp_width, (*x.ptr)->listview_layout(&offset));
}
viewport_width->set(vp_width);
return offset - viewport_y;
}
void model_set_row_data(size_t row, const ModelData &data) const
{
if (model.is_dirty()) {
std::abort();
}
if (auto m = model.get()) {
if (row < m->row_count()) {
m->set_row_data(row, data);
}
}
}
void for_each(auto &&f) const
{
if (inner) {
for (auto &&x : inner->data) {
f(*x.ptr);
}
}
}
};
template<typename C>
class Conditional
{
private_api::Property<bool> model;
mutable std::optional<ComponentHandle<C>> instance;
public:
template<typename F>
void set_model_binding(F &&binding) const
{
model.set_binding(std::forward<F>(binding));
}
template<typename Parent>
void ensure_updated(const Parent *parent) const
{
if (!model.get()) {
instance = std::nullopt;
} else if (!instance) {
instance = C::create(parent);
(*instance)->init();
}
}
uint64_t visit(TraversalOrder order, private_api::ItemVisitorRefMut visitor) const
{
if (instance) {
vtable::VRef<private_api::ItemTreeVTable> ref { &C::static_vtable,
const_cast<C *>(&(**instance)) };
if (ref.vtable->visit_children_item(ref, -1, order, visitor)
!= std::numeric_limits<uint64_t>::max()) {
return 0;
}
}
return std::numeric_limits<uint64_t>::max();
}
vtable::VWeak<private_api::ItemTreeVTable> instance_at(std::size_t i) const
{
if (i != 0 || !instance) {
return {};
}
return vtable::VWeak<private_api::ItemTreeVTable> { instance->into_dyn() };
}
private_api::IndexRange index_range() const { return private_api::IndexRange { 0, len() }; }
std::size_t len() const { return instance ? 1 : 0; }
void for_each(auto &&f) const
{
if (instance) {
f(*instance);
}
}
};
} // namespace private_api
} // namespace slint