Scanner persisted freq file, TextField for current item (#1403)

* Don't truncate string passed to Text widget

* Focus TextField on touch like other fields

* TextField for current, save last opened freq file

firmware/common/ui_widget.cpp

@@ -366,16 +366,17 @@ void Text::paint(Painter& painter) {
     const auto rect = screen_rect();
     auto s = has_focus() ? style().invert() : style();
     auto max_len = (unsigned)rect.width() / s.font.char_width();
+    auto text_view = std::string_view{text};
 
     painter.fill_rectangle(rect, s.background);
 
-    if (text.length() > max_len)
-        text.resize(max_len);
+    if (text_view.length() > max_len)
+        text_view = text_view.substr(0, max_len);
 
     painter.draw_string(
         rect.location(),
         s,
-        text);
+        text_view);
 }
 
 /* Labels ****************************************************************/
@@ -1773,6 +1774,15 @@ bool TextField::on_encoder(EncoderEvent delta) {
     return false;
 }
 
+bool TextField::on_touch(TouchEvent event) {
+    if (event.type == TouchEvent::Type::Start) {
+        focus();
+        return true;
+    }
+
+    return false;
+}
+
 /* NumberField ***********************************************************/
 
 NumberField::NumberField(

firmware/common/ui_widget.hpp

@@ -208,6 +208,10 @@ class Text : public Widget {
     void paint(Painter& painter) override;
 
    protected:
+    // NB: Don't truncate this string. The UI will only render
+    // as many characters as will fit in its rectange.
+    // Apps expect to be able to retrieve this string to avoid
+    // needing to hold additional copies in memory.
     std::string text;
 };
 
@@ -703,6 +707,7 @@ class TextField : public Text {
 
     bool on_key(KeyEvent key) override;
     bool on_encoder(EncoderEvent delta) override;
+    bool on_touch(TouchEvent event) override;
 
    private:
     using Text::set;