InfiniTime/src/displayapp/screens/Screen.h
2021-04-24 12:00:45 +03:00

77 lines
2.3 KiB
C++

#pragma once
#include <cstdint>
#include "../TouchEvents.h"
namespace Pinetime {
namespace Applications {
class DisplayApp;
namespace Screens {
template <class T> class DirtyValue {
public:
DirtyValue() = default; // Use NSDMI
explicit DirtyValue(T const& v) : value {v} {
} // Use MIL and const-lvalue-ref
bool IsUpdated() const {
return isUpdated;
}
T const& Get() {
this->isUpdated = false;
return value;
} // never expose a non-const lvalue-ref
DirtyValue& operator=(const T& other) {
if (this->value != other) {
this->value = other;
this->isUpdated = true;
}
return *this;
}
private:
T value {}; // NSDMI - default initialise type
bool isUpdated {true}; // NSDMI - use brace initilisation
};
class Screen {
public:
explicit Screen(DisplayApp* app) : app {app} {
}
virtual ~Screen() = default;
/**
* Most of the time, apps only react to events (touch events, for example).
* In this case you don't need to do anything in this method.
*
* For example, InfiniPaint does nothing in Refresh().
* But, if you want to update your display periodically, draw an animation...
* you cannot do it in a touch event handler because these handlers are not
* called if the user does not touch the screen.
*
* That's why Refresh() is there: update the display periodically.
*
* @return false if the app can be closed, true if it must continue to run
**/
virtual bool Refresh() = 0;
/** @return false if the button hasn't been handled by the app, true if it has been handled */
virtual bool OnButtonPushed() {
return false;
}
/** @return false if the event hasn't been handled by the app, true if it has been handled */
virtual bool OnTouchEvent(TouchEvents event) {
return false;
}
virtual bool OnTouchEvent(uint16_t x, uint16_t y) {
return false;
}
protected:
DisplayApp* app;
bool running = true;
};
}
}
}