#203 two button support

Author: davetcc

src/extras/TwoButtonSwitchEncoder.h

@@ -0,0 +1,64 @@
+/*
+ * Copyright (c) 2018 https://www.thecoderscorner.com (Dave Cherry).
+ * This product is licensed under an Apache license, see the LICENSE file in the top-level directory.
+ */
+
+#ifndef TCMENU_TWOBUTTONSWITCHCONTROL_H
+#define TCMENU_TWOBUTTONSWITCHCONTROL_H
+
+/**
+ * @file TwoButtonSwitchControl.h
+ * @brief contains a class that can be used to set up basic two button control of a menu
+ */
+
+#include <tcMenu.h>
+#include <IoAbstraction.h>
+
+/**
+ * Use this class to control a menu application with only two buttons. The up/down buttons double up as back and
+ * select when held. This means that repeat operation is not possible, keep integer and choice value ranges small
+ * so as to avoid needing many presses.
+ */
+class TwoButtonSwitchEncoder : public RotaryEncoder, public SwitchListener {
+private:
+    pinid_t upPin;
+    pinid_t downPin;
+
+public:
+    /**
+     * Create a two button switch given an up and down button along with the callback function for the encoder.
+     * @param up the up button (doubles as back when held)
+     * @param down the down button (doubles as OK when held)
+     * @param callbackFn the encoder change callback.
+     */
+    TwoButtonSwitchEncoder(pinid_t up, pinid_t down, EncoderCallbackFn callbackFn)
+                : RotaryEncoder(callbackFn), upPin(up), downPin(down) {
+        //switches.addSwitchListener(up, this, NO_REPEAT);
+        //switches.addSwitchListener(down, this, NO_REPEAT);
+    }
+
+    void onPressed(pinid_t pin, bool held) override {
+        // ignored as we need to only handle once the button is released.
+    }
+
+    void onReleased(pinid_t pin, bool held) override {
+        auto invert = intent == SCROLL_THROUGH_ITEMS;
+        if(pin == upPin) {
+            if(held) {
+                menuMgr.performDirectionMove(true);
+            } else {
+                int8_t dir = invert ? -stepSize : stepSize;
+                increment(dir);
+            }
+        } else if(pin == downPin) {
+            if(held) {
+                menuMgr.onMenuSelect(false);
+            } else {
+                int8_t dir = invert ? stepSize : -stepSize;
+                increment(dir);
+            }
+        }
+    }
+};
+
+#endif //TCMENU_TWOBUTTONSWITCHCONTROL_H

src/tcMenu.cpp

@@ -9,6 +9,7 @@
 #include "ScrollChoiceMenuItem.h"
 #include "MenuIterator.h"
 #include "SecuredMenuPopup.h"
+#include "extras/TwoButtonSwitchEncoder.h"
 #include <IoAbstraction.h>
 #include <BaseDialog.h>
 
@@ -59,6 +60,12 @@ void MenuManager::initFor4WayJoystick(MenuRenderer* renderer, MenuItem* root, pi
     renderer->initialise();
 }
 
+void MenuManager::initForTwoButton(MenuRenderer *r, MenuItem *root, pinid_t upPin, pinid_t downPin) {
+    this->renderer = r;
+    navigator.setRootItem(root);
+    switches.setEncoder(new TwoButtonSwitchEncoder(upPin, downPin, [](int v) { menuMgr.valueChanged(v); }));
+}
+
 void MenuManager::initForUpDownOk(MenuRenderer* renderer, MenuItem* root, pinid_t pinDown, pinid_t pinUp, pinid_t pinOk, int speed) {
     this->renderer = renderer;
     navigator.setRootItem(root);

src/tcMenu.h

@@ -218,6 +218,15 @@ class MenuManager {
     void initFor4WayJoystick(MenuRenderer* renderer, MenuItem* root, pinid_t downPin, pinid_t upPin, pinid_t leftPin,
                              pinid_t rightPin, pinid_t okPin, int speed=20);
 
+    /**
+     * Initialise for up a 2 button joystick where the up doubles as back, and the down doubles as OK when held.
+     * @param renderer the renderer used for drawing
+     * @param root the first menu item
+     * @param upPin the button on up
+     * @param downPin the button for down
+     */
+    void initForTwoButton(MenuRenderer* renderer, MenuItem* root, pinid_t upPin, pinid_t downPin);
+
     /**
 	 * Initialise in situations where local input is not needed or where a custom type of input is needed
      * that is not one of the common types.