cpp template application library (#232)

lib/app-template/app-template.cpp

@@ -0,0 +1,92 @@
+#include "flipper.h"
+#include "flipper_v2.h"
+#include "app-template.h"
+
+/*
+To use this example you need to rename
+AppExampleState - class to hold app state
+AppExampleEvent - class to hold app event
+AppExample      - app class
+app_cpp_example - function that launch app
+*/
+
+// event enumeration type
+typedef uint8_t event_t;
+
+// app state class
+class AppExampleState {
+public:
+    // state data
+    uint8_t example_data;
+
+    // state initializer
+    AppExampleState() {
+        example_data = 12;
+    }
+};
+
+// app events class
+class AppExampleEvent {
+public:
+    // events enum
+    static const event_t EventTypeTick = 0;
+    static const event_t EventTypeKey = 1;
+
+    // payload
+    union {
+        InputEvent input;
+    } value;
+
+    // event type
+    event_t type;
+};
+
+// our app derived from base AppTemplate class
+// with template variables <state, events>
+class AppExample : public AppTemplate<AppExampleState, AppExampleEvent> {
+public:
+    void run();
+    void render(CanvasApi* canvas);
+};
+
+// start app
+void AppExample::run() {
+    AppExampleEvent event;
+    while(1) {
+        if(get_event(&event, 1000)) {
+            if(event.type == AppExampleEvent::EventTypeKey) {
+                // press events
+                if(event.value.input.state && event.value.input.input == InputBack) {
+                    printf("bye!\n");
+                    exit();
+                }
+
+                if(event.value.input.state && event.value.input.input == InputUp) {
+                    // to read or write state you need to execute
+                    // acquire modify release state
+                    acquire_state();
+                    state.example_data = 24;
+                    release_state();
+                }
+            }
+        }
+
+        // signal to force gui update
+        update_gui();
+    };
+}
+
+// render app
+void AppExample::render(CanvasApi* canvas) {
+    // here you dont need to call acquire_state or release_state
+    // to read or write app state, that already handled by caller
+    canvas->set_color(canvas, ColorBlack);
+    canvas->set_font(canvas, FontPrimary);
+    canvas->draw_str(canvas, 2, state.example_data, "Example app");
+}
+
+// app enter function
+extern "C" void app_cpp_example(void* p) {
+    AppExample* app = new AppExample();
+    app->run();
+}