add example template code

applications/template/template.c

@@ -0,0 +1,103 @@
+#include "flipper_v2.h"
+
+typedef enum {
+    EventTypeTick,
+    EventTypeKey,
+    // add your events type
+} EventType;
+
+typedef struct {
+    union {
+        InputEvent input;
+        // add your events payload
+    } value;
+    EventType type;
+} Event;
+
+typedef struct {
+    // describe state here
+} State;
+
+static void render_callback(CanvasApi* canvas, void* ctx) {
+    State* state = (State*)acquire_mutex((ValueMutex*)ctx, 25);
+
+    canvas->clear(canvas);
+
+    // draw your app
+
+    release_mutex((ValueMutex*)ctx, state);
+}
+
+static void input_callback(InputEvent* input_event, void* ctx) {
+    osMessageQueueId_t event_queue = (QueueHandle_t)ctx;
+
+    Event event;
+    event.type = EventTypeKey;
+    event.value.input = *input_event;
+    osMessageQueuePut(event_queue, &event, 0, 0);
+}
+
+void template_app(void* p) {
+    osMessageQueueId_t event_queue = osMessageQueueNew(1, sizeof(Event), NULL);
+
+    State _state;
+    /* init state here */
+    ValueMutex state_mutex;
+    if(!init_mutex(&state_mutex, &_state, sizeof(State))) {
+        printf("cannot create mutex\n");
+        furiac_exit(NULL);
+    }
+
+    Widget* widget = widget_alloc();
+
+    widget_draw_callback_set(widget, render_callback, &state_mutex);
+    widget_input_callback_set(widget, input_callback, event_queue);
+
+    // Open GUI and register widget
+    GuiApi* gui = (GuiApi*)furi_open("gui");
+    if(gui == NULL) {
+        printf("gui is not available\n");
+        furiac_exit(NULL);
+    }
+    gui->add_widget(gui, widget, /* specify UI layer */);
+
+    Event event;
+    while(1) {
+        osStatus_t event_status = osMessageQueueGet(
+            event_queue,
+            &event,
+            NULL,
+            /* specify timeout */
+        );
+        State* state = (State*)acquire_mutex_block(&state_mutex);
+
+        if(event_status == osOK) {
+            if(event.type == EventTypeKey) {
+                // press events
+                if(event.value.input.state && event.value.input.input == InputBack) {
+                }
+
+                if(event.value.input.state && event.value.input.input == InputUp) {
+                }
+
+                if(event.value.input.state && event.value.input.input == InputDown) {
+                }
+
+                if(event.value.input.state && event.value.input.input == InputLeft) {
+                }
+
+                if(event.value.input.state && event.value.input.input == InputRight) {
+                }
+
+                if(event.value.input.input == InputOk) {
+                }
+            }
+        } else {
+            // event timeout
+        }
+
+        // common code, for example, force update UI
+        // widget_update(widget);
+
+        release_mutex(&state_mutex, state);
+}