[lvgl] Implement lvgl.page.is_showing: condition (#8055)

esphome/components/lvgl/automation.py

@@ -4,7 +4,7 @@ from esphome import automation
 import esphome.codegen as cg
 import esphome.config_validation as cv
 from esphome.const import CONF_ACTION, CONF_GROUP, CONF_ID, CONF_TIMEOUT
-from esphome.cpp_generator import get_variable
+from esphome.cpp_generator import TemplateArguments, get_variable
 from esphome.cpp_types import nullptr
 
 from .defines import (
@@ -23,6 +23,7 @@ from .lvcode import (
     UPDATE_EVENT,
     LambdaContext,
     LocalVariable,
+    LvglComponent,
     ReturnStatement,
     add_line_marks,
     lv,
@@ -93,7 +94,11 @@ async def lvgl_is_paused(config, condition_id, template_arg, args):
     lvgl = config[CONF_LVGL_ID]
     async with LambdaContext(LVGL_COMP_ARG, return_type=cg.bool_) as context:
         lv_add(ReturnStatement(lvgl_comp.is_paused()))
-    var = cg.new_Pvariable(condition_id, template_arg, await context.get_lambda())
+    var = cg.new_Pvariable(
+        condition_id,
+        TemplateArguments(LvglComponent, *template_arg),
+        await context.get_lambda(),
+    )
     await cg.register_parented(var, lvgl)
     return var
 
@@ -114,7 +119,11 @@ async def lvgl_is_idle(config, condition_id, template_arg, args):
     timeout = await cg.templatable(config[CONF_TIMEOUT], [], cg.uint32)
     async with LambdaContext(LVGL_COMP_ARG, return_type=cg.bool_) as context:
         lv_add(ReturnStatement(lvgl_comp.is_idle(timeout)))
-    var = cg.new_Pvariable(condition_id, template_arg, await context.get_lambda())
+    var = cg.new_Pvariable(
+        condition_id,
+        TemplateArguments(LvglComponent, *template_arg),
+        await context.get_lambda(),
+    )
     await cg.register_parented(var, lvgl)
     return var
 

esphome/components/lvgl/lvgl_esphome.cpp

@@ -119,6 +119,7 @@ void LvglComponent::add_event_cb(lv_obj_t *obj, event_callback_t callback, lv_ev
 }
 void LvglComponent::add_page(LvPageType *page) {
   this->pages_.push_back(page);
+  page->set_parent(this);
   page->setup(this->pages_.size() - 1);
 }
 void LvglComponent::show_page(size_t index, lv_scr_load_anim_t anim, uint32_t time) {
@@ -143,6 +144,8 @@ void LvglComponent::show_prev_page(lv_scr_load_anim_t anim, uint32_t time) {
   } while (this->pages_[this->current_page_]->skip);  // skip empty pages()
   this->show_page(this->current_page_, anim, time);
 }
+size_t LvglComponent::get_current_page() const { return this->current_page_; }
+bool LvPageType::is_showing() const { return this->parent_->get_current_page() == this->index; }
 void LvglComponent::draw_buffer_(const lv_area_t *area, lv_color_t *ptr) {
   auto width = lv_area_get_width(area);
   auto height = lv_area_get_height(area);

esphome/components/lvgl/lvgl_esphome.h

@@ -94,7 +94,9 @@ class LvCompound {
   lv_obj_t *obj{};
 };
 
-class LvPageType {
+class LvglComponent;
+
+class LvPageType : public Parented<LvglComponent> {
  public:
   LvPageType(bool skip) : skip(skip) {}
 
@@ -102,6 +104,9 @@ class LvPageType {
     this->index = index;
     this->obj = lv_obj_create(nullptr);
   }
+
+  bool is_showing() const;
+
   lv_obj_t *obj{};
   size_t index{};
   bool skip;
@@ -188,6 +193,7 @@ class LvglComponent : public PollingComponent {
   void show_next_page(lv_scr_load_anim_t anim, uint32_t time);
   void show_prev_page(lv_scr_load_anim_t anim, uint32_t time);
   void set_page_wrap(bool wrap) { this->page_wrap_ = wrap; }
+  size_t get_current_page() const;
   void set_focus_mark(lv_group_t *group) { this->focus_marks_[group] = lv_group_get_focused(group); }
   void restore_focus_mark(lv_group_t *group) {
     auto *mark = this->focus_marks_[group];
@@ -251,14 +257,13 @@ template<typename... Ts> class LvglAction : public Action<Ts...>, public Parente
   std::function<void(LvglComponent *)> action_{};
 };
 
-template<typename... Ts> class LvglCondition : public Condition<Ts...>, public Parented<LvglComponent> {
+template<typename Tc, typename... Ts> class LvglCondition : public Condition<Ts...>, public Parented<Tc> {
  public:
-  LvglCondition(std::function<bool(LvglComponent *)> &&condition_lambda)
-      : condition_lambda_(std::move(condition_lambda)) {}
+  LvglCondition(std::function<bool(Tc *)> &&condition_lambda) : condition_lambda_(std::move(condition_lambda)) {}
   bool check(Ts... x) override { return this->condition_lambda_(this->parent_); }
 
  protected:
-  std::function<bool(LvglComponent *)> condition_lambda_{};
+  std::function<bool(Tc *)> condition_lambda_{};
 };
 
 #ifdef USE_LVGL_TOUCHSCREEN

esphome/components/lvgl/widgets/page.py

@@ -2,6 +2,7 @@ from esphome import automation, codegen as cg
 from esphome.automation import Trigger
 import esphome.config_validation as cv
 from esphome.const import CONF_ID, CONF_PAGES, CONF_TIME, CONF_TRIGGER_ID
+from esphome.cpp_generator import MockObj, TemplateArguments
 
 from ..defines import (
     CONF_ANIMATION,
@@ -17,18 +18,28 @@ from ..lvcode import (
     EVENT_ARG,
     LVGL_COMP_ARG,
     LambdaContext,
+    ReturnStatement,
     add_line_marks,
     lv_add,
     lvgl_comp,
     lvgl_static,
 )
 from ..schemas import LVGL_SCHEMA
-from ..types import LvglAction, lv_page_t
-from . import Widget, WidgetType, add_widgets, get_widgets, set_obj_properties
+from ..types import LvglAction, LvglCondition, lv_page_t
+from . import (
+    Widget,
+    WidgetType,
+    add_widgets,
+    get_widgets,
+    set_obj_properties,
+    wait_for_widgets,
+)
 
 CONF_ON_LOAD = "on_load"
 CONF_ON_UNLOAD = "on_unload"
 
+PAGE_ARG = "_page"
+
 PAGE_SCHEMA = cv.Schema(
     {
         cv.Optional(CONF_SKIP, default=False): lv_bool,
@@ -86,6 +97,30 @@ async def page_next_to_code(config, action_id, template_arg, args):
     return var
 
 
+@automation.register_condition(
+    "lvgl.page.is_showing",
+    LvglCondition,
+    cv.maybe_simple_value(
+        cv.Schema({cv.Required(CONF_ID): cv.use_id(lv_page_t)}),
+        key=CONF_ID,
+    ),
+)
+async def page_is_showing_to_code(config, condition_id, template_arg, args):
+    await wait_for_widgets()
+    page = await cg.get_variable(config[CONF_ID])
+    async with LambdaContext(
+        [(lv_page_t.operator("ptr"), PAGE_ARG)], return_type=cg.bool_
+    ) as context:
+        lv_add(ReturnStatement(MockObj(PAGE_ARG, "->").is_showing()))
+    var = cg.new_Pvariable(
+        condition_id,
+        TemplateArguments(lv_page_t, *template_arg),
+        await context.get_lambda(),
+    )
+    await cg.register_parented(var, page)
+    return var
+
+
 @automation.register_action(
     "lvgl.page.previous",
     LvglAction,

tests/components/lvgl/lvgl-package.yaml

@@ -138,6 +138,11 @@ lvgl:
         - logger.log: page loaded
         - lvgl.widget.focus:
             action: restore
+        - if:
+            condition:
+              lvgl.page.is_showing: page1
+            then:
+              logger.log: "Yes, page1 showing"
       on_unload:
         - logger.log: page unloaded
         - lvgl.widget.focus: mark