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// dear imgui: Platform Binding for Android native app
// This needs to be used along with the OpenGL 3 Renderer (imgui_impl_opengl3)
// Implemented features:
// [X] Platform: Keyboard support. Since 1.87 we are using the io.AddKeyEvent() function. Pass ImGuiKey values to all key functions e.g. ImGui::IsKeyPressed(ImGuiKey_Space). [Legacy AKEYCODE_* values will also be supported unless IMGUI_DISABLE_OBSOLETE_KEYIO is set]
// Missing features:
// [ ] Platform: Clipboard support.
// [ ] Platform: Gamepad support. Enable with 'io.ConfigFlags |= ImGuiConfigFlags_NavEnableGamepad'.
// [ ] Platform: Mouse cursor shape and visibility. Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'. FIXME: Check if this is even possible with Android.
// Important:
// - FIXME: On-screen keyboard currently needs to be enabled by the application (see examples/ and issue #3446)
// - FIXME: Unicode character inputs needs to be passed by Dear ImGui by the application (see examples/ and issue #3446)
// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
// If you are new to Dear ImGui, read documentation from the docs/ folder + read the top of imgui.cpp.
// Read online:
// (minor and older changes stripped away, please see git history for details)
// 2022-01-05: Inputs: calling new io.AddKeyEvent() API (1.87+), support for full keys range.
// 2021-03-04: Initial version.
#include "imgui.h"
#include "imgui_impl_android.h"
#include <time.h>
#include <map>
#include <queue>
#include <android/native_window.h>
#include <android/input.h>
#include <android/keycodes.h>
#include <android/log.h>
// Android data
static double g_Time = 0.0;
static ANativeWindow* g_Window;
static char g_LogTag[] = "ImGuiExample";
static std::map<ImGuiKey, std::queue<ImGuiIOKeyEvent>> g_KeyEventQueues; // FIXME: Remove dependency on map and queue once we use upcoming input queue.
static ImGuiKeyModFlags g_KeyModFlags = ImGuiKeyModFlags_None;
static ImGuiKey ImGui_ImplAndroid_KeyCodeToImGuiKey(int32_t key_code)
switch (key_code)
case AKEYCODE_TAB: return ImGuiKey_Tab;
case AKEYCODE_DPAD_LEFT: return ImGuiKey_LeftArrow;
case AKEYCODE_DPAD_RIGHT: return ImGuiKey_RightArrow;
case AKEYCODE_DPAD_UP: return ImGuiKey_UpArrow;
case AKEYCODE_DPAD_DOWN: return ImGuiKey_DownArrow;
case AKEYCODE_PAGE_UP: return ImGuiKey_PageUp;
case AKEYCODE_PAGE_DOWN: return ImGuiKey_PageDown;
case AKEYCODE_MOVE_HOME: return ImGuiKey_Home;
case AKEYCODE_MOVE_END: return ImGuiKey_End;
case AKEYCODE_INSERT: return ImGuiKey_Insert;
case AKEYCODE_FORWARD_DEL: return ImGuiKey_Delete;
case AKEYCODE_DEL: return ImGuiKey_Backspace;
case AKEYCODE_SPACE: return ImGuiKey_Space;
case AKEYCODE_ENTER: return ImGuiKey_Enter;
case AKEYCODE_ESCAPE: return ImGuiKey_Escape;
case AKEYCODE_APOSTROPHE: return ImGuiKey_Apostrophe;
case AKEYCODE_COMMA: return ImGuiKey_Comma;
case AKEYCODE_MINUS: return ImGuiKey_Minus;
case AKEYCODE_PERIOD: return ImGuiKey_Period;
case AKEYCODE_SLASH: return ImGuiKey_Slash;
case AKEYCODE_SEMICOLON: return ImGuiKey_Semicolon;
case AKEYCODE_EQUALS: return ImGuiKey_Equal;
case AKEYCODE_LEFT_BRACKET: return ImGuiKey_LeftBracket;
case AKEYCODE_BACKSLASH: return ImGuiKey_Backslash;
case AKEYCODE_RIGHT_BRACKET: return ImGuiKey_RightBracket;
case AKEYCODE_GRAVE: return ImGuiKey_GraveAccent;
case AKEYCODE_CAPS_LOCK: return ImGuiKey_CapsLock;
case AKEYCODE_SCROLL_LOCK: return ImGuiKey_ScrollLock;
case AKEYCODE_NUM_LOCK: return ImGuiKey_NumLock;
case AKEYCODE_SYSRQ: return ImGuiKey_PrintScreen;
case AKEYCODE_BREAK: return ImGuiKey_Pause;
case AKEYCODE_NUMPAD_0: return ImGuiKey_Keypad0;
case AKEYCODE_NUMPAD_1: return ImGuiKey_Keypad1;
case AKEYCODE_NUMPAD_2: return ImGuiKey_Keypad2;
case AKEYCODE_NUMPAD_3: return ImGuiKey_Keypad3;
case AKEYCODE_NUMPAD_4: return ImGuiKey_Keypad4;
case AKEYCODE_NUMPAD_5: return ImGuiKey_Keypad5;
case AKEYCODE_NUMPAD_6: return ImGuiKey_Keypad6;
case AKEYCODE_NUMPAD_7: return ImGuiKey_Keypad7;
case AKEYCODE_NUMPAD_8: return ImGuiKey_Keypad8;
case AKEYCODE_NUMPAD_9: return ImGuiKey_Keypad9;
case AKEYCODE_NUMPAD_DOT: return ImGuiKey_KeypadDecimal;
case AKEYCODE_NUMPAD_DIVIDE: return ImGuiKey_KeypadDivide;
case AKEYCODE_NUMPAD_MULTIPLY: return ImGuiKey_KeypadMultiply;
case AKEYCODE_NUMPAD_SUBTRACT: return ImGuiKey_KeypadSubtract;
case AKEYCODE_NUMPAD_ADD: return ImGuiKey_KeypadAdd;
case AKEYCODE_NUMPAD_ENTER: return ImGuiKey_KeypadEnter;
case AKEYCODE_NUMPAD_EQUALS: return ImGuiKey_KeypadEqual;
case AKEYCODE_SHIFT_LEFT: return ImGuiKey_LeftShift;
case AKEYCODE_CTRL_LEFT: return ImGuiKey_LeftControl;
case AKEYCODE_ALT_LEFT: return ImGuiKey_LeftAlt;
case AKEYCODE_META_LEFT: return ImGuiKey_LeftSuper;
case AKEYCODE_SHIFT_RIGHT: return ImGuiKey_RightShift;
case AKEYCODE_CTRL_RIGHT: return ImGuiKey_RightControl;
case AKEYCODE_ALT_RIGHT: return ImGuiKey_RightAlt;
case AKEYCODE_META_RIGHT: return ImGuiKey_RightSuper;
case AKEYCODE_MENU: return ImGuiKey_Menu;
case AKEYCODE_0: return ImGuiKey_0;
case AKEYCODE_1: return ImGuiKey_1;
case AKEYCODE_2: return ImGuiKey_2;
case AKEYCODE_3: return ImGuiKey_3;
case AKEYCODE_4: return ImGuiKey_4;
case AKEYCODE_5: return ImGuiKey_5;
case AKEYCODE_6: return ImGuiKey_6;
case AKEYCODE_7: return ImGuiKey_7;
case AKEYCODE_8: return ImGuiKey_8;
case AKEYCODE_9: return ImGuiKey_9;
case AKEYCODE_A: return ImGuiKey_A;
case AKEYCODE_B: return ImGuiKey_B;
case AKEYCODE_C: return ImGuiKey_C;
case AKEYCODE_D: return ImGuiKey_D;
case AKEYCODE_E: return ImGuiKey_E;
case AKEYCODE_F: return ImGuiKey_F;
case AKEYCODE_G: return ImGuiKey_G;
case AKEYCODE_H: return ImGuiKey_H;
case AKEYCODE_I: return ImGuiKey_I;
case AKEYCODE_J: return ImGuiKey_J;
case AKEYCODE_K: return ImGuiKey_K;
case AKEYCODE_L: return ImGuiKey_L;
case AKEYCODE_M: return ImGuiKey_M;
case AKEYCODE_N: return ImGuiKey_N;
case AKEYCODE_O: return ImGuiKey_O;
case AKEYCODE_P: return ImGuiKey_P;
case AKEYCODE_Q: return ImGuiKey_Q;
case AKEYCODE_R: return ImGuiKey_R;
case AKEYCODE_S: return ImGuiKey_S;
case AKEYCODE_T: return ImGuiKey_T;
case AKEYCODE_U: return ImGuiKey_U;
case AKEYCODE_V: return ImGuiKey_V;
case AKEYCODE_W: return ImGuiKey_W;
case AKEYCODE_X: return ImGuiKey_X;
case AKEYCODE_Y: return ImGuiKey_Y;
case AKEYCODE_Z: return ImGuiKey_Z;
case AKEYCODE_F1: return ImGuiKey_F1;
case AKEYCODE_F2: return ImGuiKey_F2;
case AKEYCODE_F3: return ImGuiKey_F3;
case AKEYCODE_F4: return ImGuiKey_F4;
case AKEYCODE_F5: return ImGuiKey_F5;
case AKEYCODE_F6: return ImGuiKey_F6;
case AKEYCODE_F7: return ImGuiKey_F7;
case AKEYCODE_F8: return ImGuiKey_F8;
case AKEYCODE_F9: return ImGuiKey_F9;
case AKEYCODE_F10: return ImGuiKey_F10;
case AKEYCODE_F11: return ImGuiKey_F11;
case AKEYCODE_F12: return ImGuiKey_F12;
default: return ImGuiKey_None;
int32_t ImGui_ImplAndroid_HandleInputEvent(AInputEvent* input_event)
ImGuiIO& io = ImGui::GetIO();
int32_t event_type = AInputEvent_getType(input_event);
switch (event_type)
int32_t event_key_code = AKeyEvent_getKeyCode(input_event);
int32_t event_scan_code = AKeyEvent_getScanCode(input_event);
int32_t event_action = AKeyEvent_getAction(input_event);
int32_t event_meta_state = AKeyEvent_getMetaState(input_event);
g_KeyModFlags = ImGuiKeyModFlags_None;
if ((event_meta_state & AMETA_CTRL_ON) != 0)
g_KeyModFlags |= ImGuiKeyModFlags_Ctrl;
if ((event_meta_state & AMETA_SHIFT_ON) != 0)
g_KeyModFlags |= ImGuiKeyModFlags_Shift;
if ((event_meta_state & AMETA_ALT_ON) != 0)
g_KeyModFlags |= ImGuiKeyModFlags_Alt;
if ((event_meta_state & AMETA_META_ON) != 0)
g_KeyModFlags |= ImGuiKeyModFlags_Super;
switch (event_action)
// FIXME: AKEY_EVENT_ACTION_DOWN and AKEY_EVENT_ACTION_UP occur at once as soon as a touch pointer
// goes up from a key. We use a simple key event queue/ and process one event per key per frame in
// ImGui_ImplAndroid_NewFrame()...or consider using IO queue, if suitable:
ImGuiKey key = ImGui_ImplAndroid_KeyCodeToImGuiKey(event_key_code);
if (key != ImGuiKey_None && (event_action == AKEY_EVENT_ACTION_DOWN || event_action == AKEY_EVENT_ACTION_UP))
ImGuiIOKeyEvent io_event;
io_event.Key = key;
io_event.Down = event_action == AKEY_EVENT_ACTION_DOWN;
io_event.NativeKeycode = event_key_code;
io_event.NativeScancode = event_scan_code;
int32_t event_action = AMotionEvent_getAction(input_event);
switch (event_action)
// Physical mouse buttons (and probably other physical devices) also invoke the actions AMOTION_EVENT_ACTION_DOWN/_UP,
// but we have to process them separately to identify the actual button pressed. This is done below via
// AMOTION_EVENT_ACTION_BUTTON_PRESS/_RELEASE. Here, we only process "FINGER" input (and "UNKNOWN", as a fallback).
if((AMotionEvent_getToolType(input_event, event_pointer_index) == AMOTION_EVENT_TOOL_TYPE_FINGER)
|| (AMotionEvent_getToolType(input_event, event_pointer_index) == AMOTION_EVENT_TOOL_TYPE_UNKNOWN))
io.MouseDown[0] = (event_action == AMOTION_EVENT_ACTION_DOWN);
io.MousePos = ImVec2(AMotionEvent_getX(input_event, event_pointer_index), AMotionEvent_getY(input_event, event_pointer_index));
int32_t button_state = AMotionEvent_getButtonState(input_event);
io.MouseDown[0] = ((button_state & AMOTION_EVENT_BUTTON_PRIMARY) != 0);
io.MouseDown[1] = ((button_state & AMOTION_EVENT_BUTTON_SECONDARY) != 0);
io.MouseDown[2] = ((button_state & AMOTION_EVENT_BUTTON_TERTIARY) != 0);
case AMOTION_EVENT_ACTION_HOVER_MOVE: // Hovering: Tool moves while NOT pressed (such as a physical mouse)
case AMOTION_EVENT_ACTION_MOVE: // Touch pointer moves while DOWN
io.MousePos = ImVec2(AMotionEvent_getX(input_event, event_pointer_index), AMotionEvent_getY(input_event, event_pointer_index));
io.MouseWheel = AMotionEvent_getAxisValue(input_event, AMOTION_EVENT_AXIS_VSCROLL, event_pointer_index);
io.MouseWheelH = AMotionEvent_getAxisValue(input_event, AMOTION_EVENT_AXIS_HSCROLL, event_pointer_index);
return 1;
return 0;
bool ImGui_ImplAndroid_Init(ANativeWindow* window)
g_Window = window;
g_Time = 0.0;
// Setup backend capabilities flags
ImGuiIO& io = ImGui::GetIO();
io.BackendPlatformName = "imgui_impl_android";
return true;
void ImGui_ImplAndroid_Shutdown()
void ImGui_ImplAndroid_NewFrame()
ImGuiIO& io = ImGui::GetIO();
// Process queued key events
// FIXME: This is a workaround for multiple key event actions occurring at once (see above) and can be removed once we use upcoming input queue.
for (auto& key_queue : g_KeyEventQueues)
if (key_queue.second.empty())
// Setup display size (every frame to accommodate for window resizing)
int32_t window_width = ANativeWindow_getWidth(g_Window);
int32_t window_height = ANativeWindow_getHeight(g_Window);
int display_width = window_width;
int display_height = window_height;
io.DisplaySize = ImVec2((float)window_width, (float)window_height);
if (window_width > 0 && window_height > 0)
io.DisplayFramebufferScale = ImVec2((float)display_width / window_width, (float)display_height / window_height);
// Setup time step
struct timespec current_timespec;
clock_gettime(CLOCK_MONOTONIC, &current_timespec);
double current_time = (double)(current_timespec.tv_sec) + (current_timespec.tv_nsec / 1000000000.0);
io.DeltaTime = g_Time > 0.0 ? (float)(current_time - g_Time) : (float)(1.0f / 60.0f);
g_Time = current_time;