perf(core/rust): use less Button instances in PassphraseKeyboard

[no changelog]

core/embed/rust/src/ui/model_tt/component/keyboard/passphrase.rs

@@ -24,7 +24,7 @@ pub struct PassphraseKeyboard {
     input: Child<Input>,
     back: Child<Button<&'static str>>,
     confirm: Child<Button<&'static str>>,
-    keys: [[Child<Button<&'static str>>; KEY_COUNT]; PAGE_COUNT],
+    keys: [Child<Button<&'static str>>; KEY_COUNT],
     scrollbar: ScrollBar,
     fade: bool,
 }
@@ -59,16 +59,8 @@ impl PassphraseKeyboard {
             .initially_enabled(false)
             .with_long_press(theme::ERASE_HOLD_DURATION)
             .into_child(),
-            keys: KEYBOARD.map(|page| {
+            keys: KEYBOARD[STARTING_PAGE]
-                page.map(|text| {
+                .map(|text| Child::new(Button::new(Self::key_content(text)))),
-                    if text == " " {
-                        let icon = Icon::new(theme::ICON_SPACE);
-                        Child::new(Button::with_icon(icon))
-                    } else {
-                        Child::new(Button::with_text(text))
-                    }
-                })
-            }),
             scrollbar: ScrollBar::horizontal(),
             fade: false,
         }
@@ -83,6 +75,13 @@ impl PassphraseKeyboard {
         }
     }
 
+    fn key_content(text: &'static str) -> ButtonContent<&'static str> {
+        match text {
+            " " => ButtonContent::Icon(Icon::new(theme::ICON_SPACE)),
+            t => ButtonContent::Text(t),
+        }
+    }
+
     fn on_page_swipe(&mut self, ctx: &mut EventCtx, swipe: SwipeDirection) {
         // Change the page number.
         let key_page = self.scrollbar.active_page;
@@ -95,10 +94,8 @@ impl PassphraseKeyboard {
         // Clear the pending state.
         self.input
             .mutate(ctx, |ctx, i| i.multi_tap.clear_pending_state(ctx));
-        // Make sure to completely repaint the new buttons.
+        // Update buttons.
-        for btn in &mut self.keys[key_page] {
+        self.replace_button_content(ctx, key_page);
-            btn.request_complete_repaint(ctx);
-        }
         // Reset backlight to normal level on next paint.
         self.fade = true;
         // So that swipe does not visually enable the input buttons when max length
@@ -106,6 +103,15 @@ impl PassphraseKeyboard {
         self.update_input_btns_state(ctx);
     }
 
+    fn replace_button_content(&mut self, ctx: &mut EventCtx, page: usize) {
+        for (i, btn) in self.keys.iter_mut().enumerate() {
+            let text = KEYBOARD[page][i];
+            let content = Self::key_content(text);
+            btn.mutate(ctx, |ctx, b| b.set_content(ctx, content));
+            btn.request_complete_repaint(ctx);
+        }
+    }
+
     /// Possibly changing the buttons' state after change of the input.
     fn after_edit(&mut self, ctx: &mut EventCtx) {
         self.update_back_btn_state(ctx);
@@ -123,7 +129,7 @@ impl PassphraseKeyboard {
 
     /// When the input has reached max length, disable all the input buttons.
     fn update_input_btns_state(&mut self, ctx: &mut EventCtx) {
-        for btn in self.keys[self.scrollbar.active_page].iter_mut() {
+        for btn in self.keys.iter_mut() {
             btn.mutate(ctx, |ctx, b| {
                 if self.input.inner().textbox.is_full() {
                     b.disable(ctx);
@@ -164,9 +170,8 @@ impl Component for PassphraseKeyboard {
         self.scrollbar
             .set_count_and_active_page(PAGE_COUNT, STARTING_PAGE);
 
-        // Place all the possible character buttons on all swipe-separated screens.
+        // Place all the character buttons.
-        for swipe_screen in &mut self.keys {
+        for (key, btn) in &mut self.keys.iter_mut().enumerate() {
-            for (key, btn) in swipe_screen.iter_mut().enumerate() {
             // Assign the keys in each page to buttons on a 5x3 grid, starting
             // from the second row.
             let area = key_grid.cell(if key < 9 {
@@ -178,7 +183,6 @@ impl Component for PassphraseKeyboard {
             });
             btn.place(area);
         }
-        }
 
         bounds
     }
@@ -229,7 +233,7 @@ impl Component for PassphraseKeyboard {
         // (All input buttons should be disallowed in that case, this is just a safety
         // measure.)
         if !self.input.inner().textbox.is_full() {
-            for (key, btn) in self.keys[self.scrollbar.active_page].iter_mut().enumerate() {
+            for (key, btn) in self.keys.iter_mut().enumerate() {
                 if let Some(ButtonMsg::Clicked) = btn.event(ctx, event) {
                     // Key button was clicked. If this button is pending, let's cycle the pending
                     // character in textbox. If not, let's just append the first character.
@@ -251,7 +255,7 @@ impl Component for PassphraseKeyboard {
         self.scrollbar.paint();
         self.confirm.paint();
         self.back.paint();
-        for btn in &mut self.keys[self.scrollbar.active_page] {
+        for btn in &mut self.keys {
             btn.paint();
         }
         if self.fade {
@@ -266,7 +270,7 @@ impl Component for PassphraseKeyboard {
         self.scrollbar.bounds(sink);
         self.confirm.bounds(sink);
         self.back.bounds(sink);
-        for btn in &self.keys[self.scrollbar.active_page] {
+        for btn in &self.keys {
             btn.bounds(sink)
         }
     }