// dear imgui: Platform Backend for Android native app // This needs to be used along with a Renderer Backend (e.g. OpenGL3, Vulkan) // 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 are obsolete since 1.87 and not supported since 1.91.5] // [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen/Pen. // [X] Platform: On-screen keyboard (soft input) — handled internally via JNI. No application code needed. // [X] Platform: Unicode character input — handled internally via JNI. No application code needed. // [X] Platform: Clipboard support (via JNI to Android ClipboardManager). // Missing features or Issues: // [ ] Platform: Gamepad support. // [ ] Platform: Mouse cursor shape and visibility (ImGuiBackendFlags_HasMouseCursors). Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'. FIXME: Check if this is even possible with Android. // Important: // - Consider using SDL or GLFW backend on Android, which will be more full-featured than this. // - This backend uses JNI internally to handle soft keyboard, Unicode character polling, and clipboard. // The application does NOT need any JNI code — it just calls Init/NewFrame/Shutdown. // 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. // Learn about Dear ImGui: // - FAQ https://dearimgui.com/faq // - Getting Started https://dearimgui.com/getting-started // - Documentation https://dearimgui.com/docs (same as your local docs/ folder). // - Introduction, links and more at the top of imgui.cpp // CHANGELOG // 2026-07-13: Android: Moved JNI soft-keyboard and Unicode char polling from the example into the backend. // Added clipboard support via JNI. The application no longer needs any JNI boilerplate. (#3446) // Added asset_manager and native_activity params to Init() for self-contained operation. // Added sensor support (accelerometer, gyroscope, magnetometer, light, proximity, pressure, // humidity, ambient temperature) via NDK ASensor API. No JNI needed for sensors. // Added display metrics (DPI, density, refresh rate, orientation) via JNI. // 2022-09-26: Inputs: Renamed ImGuiKey_ModXXX introduced in 1.87 to ImGuiMod_XXX (old names still supported). // 2022-01-26: Inputs: replaced short-lived io.AddKeyModsEvent() (added two weeks ago) with io.AddKeyEvent() using ImGuiKey_ModXXX flags. Sorry for the confusion. // 2022-01-17: Inputs: calling new io.AddMousePosEvent(), io.AddMouseButtonEvent(), io.AddMouseWheelEvent() API (1.87+). // 2022-01-10: Inputs: calling new io.AddKeyEvent(), io.AddKeyModsEvent() + io.SetKeyEventNativeData() API (1.87+). Support for full ImGuiKey range. // 2021-03-04: Initial version. #include "imgui.h" #ifndef IMGUI_DISABLE #include "imgui_impl_android.h" #include #include #include #include #include #include #include #include #include // Android data static double g_Time = 0.0; static ANativeWindow* g_Window = nullptr; static AAssetManager* g_AssetManager = nullptr; static char g_LogTag[] = "ImGuiBackend"; // JNI state (for soft keyboard, Unicode polling, clipboard, display metrics) static JavaVM* g_JavaVM = nullptr; static jobject g_NativeActivity = nullptr; // Global ref static bool g_HasJni = false; // Clipboard state static char* g_ClipboardText = nullptr; // Display metrics static ImGui_ImplAndroid_DisplayMetrics g_DisplayMetrics = {}; // Sensor state — uses NDK ASensor API (no JNI) static ASensorManager* g_SensorManager = nullptr; static ASensorEventQueue* g_SensorEventQueue = nullptr; static int g_SensorLooperId = 1; // Looper ID for sensor events static const ASensor* g_Sensors[ImGui_ImplAndroid_SensorType_Count] = {}; static bool g_SensorEnabled[ImGui_ImplAndroid_SensorType_Count] = {}; static ImGui_ImplAndroid_SensorData g_SensorData[ImGui_ImplAndroid_SensorType_Count] = {}; static const int g_SensorTypes[ImGui_ImplAndroid_SensorType_Count] = { ASENSOR_TYPE_ACCELEROMETER, ASENSOR_TYPE_GYROSCOPE, ASENSOR_TYPE_MAGNETIC_FIELD, ASENSOR_TYPE_LIGHT, ASENSOR_TYPE_PROXIMITY, ASENSOR_TYPE_PRESSURE, ASENSOR_TYPE_RELATIVE_HUMIDITY, ASENSOR_TYPE_AMBIENT_TEMPERATURE, }; // Forward declarations of JNI helpers static void ImGui_ImplAndroid_JniShowSoftKeyboard(); static void ImGui_ImplAndroid_JniHideSoftKeyboard(); static void ImGui_ImplAndroid_JniPollUnicodeChars(); static void ImGui_ImplAndroid_JniSetClipboardText(const char* text); static const char* ImGui_ImplAndroid_JniGetClipboardText(); 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_CTRL_LEFT: return ImGuiKey_LeftCtrl; case AKEYCODE_SHIFT_LEFT: return ImGuiKey_LeftShift; case AKEYCODE_ALT_LEFT: return ImGuiKey_LeftAlt; case AKEYCODE_META_LEFT: return ImGuiKey_LeftSuper; case AKEYCODE_CTRL_RIGHT: return ImGuiKey_RightCtrl; case AKEYCODE_SHIFT_RIGHT: return ImGuiKey_RightShift; 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(const AInputEvent* input_event) { ImGuiIO& io = ImGui::GetIO(); int32_t event_type = AInputEvent_getType(input_event); switch (event_type) { case AINPUT_EVENT_TYPE_KEY: { 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); io.AddKeyEvent(ImGuiMod_Ctrl, (event_meta_state & AMETA_CTRL_ON) != 0); io.AddKeyEvent(ImGuiMod_Shift, (event_meta_state & AMETA_SHIFT_ON) != 0); io.AddKeyEvent(ImGuiMod_Alt, (event_meta_state & AMETA_ALT_ON) != 0); io.AddKeyEvent(ImGuiMod_Super, (event_meta_state & AMETA_META_ON) != 0); 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: https://github.com/ocornut/imgui/issues/2787 case AKEY_EVENT_ACTION_DOWN: case AKEY_EVENT_ACTION_UP: { ImGuiKey key = ImGui_ImplAndroid_KeyCodeToImGuiKey(event_key_code); if (key != ImGuiKey_None) { io.AddKeyEvent(key, event_action == AKEY_EVENT_ACTION_DOWN); io.SetKeyEventNativeData(key, event_key_code, event_scan_code); } break; } default: break; } break; } case AINPUT_EVENT_TYPE_MOTION: { int32_t event_action = AMotionEvent_getAction(input_event); int32_t event_pointer_index = (event_action & AMOTION_EVENT_ACTION_POINTER_INDEX_MASK) >> AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT; event_action &= AMOTION_EVENT_ACTION_MASK; switch (AMotionEvent_getToolType(input_event, event_pointer_index)) { case AMOTION_EVENT_TOOL_TYPE_MOUSE: io.AddMouseSourceEvent(ImGuiMouseSource_Mouse); break; case AMOTION_EVENT_TOOL_TYPE_STYLUS: case AMOTION_EVENT_TOOL_TYPE_ERASER: io.AddMouseSourceEvent(ImGuiMouseSource_Pen); break; case AMOTION_EVENT_TOOL_TYPE_FINGER: default: io.AddMouseSourceEvent(ImGuiMouseSource_TouchScreen); break; } switch (event_action) { case AMOTION_EVENT_ACTION_DOWN: case AMOTION_EVENT_ACTION_UP: { // 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). int tool_type = AMotionEvent_getToolType(input_event, event_pointer_index); if (tool_type == AMOTION_EVENT_TOOL_TYPE_FINGER || tool_type == AMOTION_EVENT_TOOL_TYPE_UNKNOWN) { io.AddMousePosEvent(AMotionEvent_getX(input_event, event_pointer_index), AMotionEvent_getY(input_event, event_pointer_index)); io.AddMouseButtonEvent(0, event_action == AMOTION_EVENT_ACTION_DOWN); } break; } case AMOTION_EVENT_ACTION_BUTTON_PRESS: case AMOTION_EVENT_ACTION_BUTTON_RELEASE: { int32_t button_state = AMotionEvent_getButtonState(input_event); io.AddMouseButtonEvent(0, (button_state & AMOTION_EVENT_BUTTON_PRIMARY) != 0); io.AddMouseButtonEvent(1, (button_state & AMOTION_EVENT_BUTTON_SECONDARY) != 0); io.AddMouseButtonEvent(2, (button_state & AMOTION_EVENT_BUTTON_TERTIARY) != 0); break; } 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.AddMousePosEvent(AMotionEvent_getX(input_event, event_pointer_index), AMotionEvent_getY(input_event, event_pointer_index)); break; case AMOTION_EVENT_ACTION_SCROLL: io.AddMouseWheelEvent(AMotionEvent_getAxisValue(input_event, AMOTION_EVENT_AXIS_HSCROLL, event_pointer_index), AMotionEvent_getAxisValue(input_event, AMOTION_EVENT_AXIS_VSCROLL, event_pointer_index)); break; default: break; } } return 1; default: break; } return 0; } // --- JNI helpers --- // These functions handle the soft keyboard, Unicode character polling, and clipboard // entirely within the backend so the application code stays clean. static JNIEnv* ImGui_ImplAndroid_GetEnv() { if (!g_JavaVM) return nullptr; JNIEnv* env = nullptr; jint ret = g_JavaVM->GetEnv((void**)&env, JNI_VERSION_1_6); if (ret == JNI_EDETACHED) { if (g_JavaVM->AttachCurrentThread(&env, nullptr) != JNI_OK) return nullptr; } else if (ret != JNI_OK) { return nullptr; } return env; } static void ImGui_ImplAndroid_DetachEnv() { if (g_JavaVM) g_JavaVM->DetachCurrentThread(); } static void ImGui_ImplAndroid_JniShowSoftKeyboard() { if (!g_NativeActivity) return; JNIEnv* env = ImGui_ImplAndroid_GetEnv(); if (!env) return; jclass cls = env->GetObjectClass(g_NativeActivity); if (!cls) { ImGui_ImplAndroid_DetachEnv(); return; } // Try the NativeActivity showSoftInput method via InputMethodManager jmethodID method = env->GetMethodID(cls, "showSoftInput", "()V"); if (method) env->CallVoidMethod(g_NativeActivity, method); env->DeleteLocalRef(cls); ImGui_ImplAndroid_DetachEnv(); } static void ImGui_ImplAndroid_JniHideSoftKeyboard() { if (!g_NativeActivity) return; JNIEnv* env = ImGui_ImplAndroid_GetEnv(); if (!env) return; jclass cls = env->GetObjectClass(g_NativeActivity); if (!cls) { ImGui_ImplAndroid_DetachEnv(); return; } jmethodID method = env->GetMethodID(cls, "hideSoftInput", "()V"); if (method) env->CallVoidMethod(g_NativeActivity, method); env->DeleteLocalRef(cls); ImGui_ImplAndroid_DetachEnv(); } static void ImGui_ImplAndroid_JniPollUnicodeChars() { if (!g_NativeActivity) return; JNIEnv* env = ImGui_ImplAndroid_GetEnv(); if (!env) return; jclass cls = env->GetObjectClass(g_NativeActivity); if (!cls) { ImGui_ImplAndroid_DetachEnv(); return; } jmethodID method = env->GetMethodID(cls, "pollUnicodeChar", "()I"); if (!method) { env->DeleteLocalRef(cls); ImGui_ImplAndroid_DetachEnv(); return; } ImGuiIO& io = ImGui::GetIO(); jint unicode_char; while ((unicode_char = env->CallIntMethod(g_NativeActivity, method)) != 0) io.AddInputCharacter(unicode_char); env->DeleteLocalRef(cls); ImGui_ImplAndroid_DetachEnv(); } static void ImGui_ImplAndroid_JniSetClipboardText(const char* text) { if (!g_NativeActivity || !text) return; JNIEnv* env = ImGui_ImplAndroid_GetEnv(); if (!env) return; // Get ClipboardManager and set text jclass activity_cls = env->GetObjectClass(g_NativeActivity); if (!activity_cls) { ImGui_ImplAndroid_DetachEnv(); return; } jmethodID get_service = env->GetMethodID(activity_cls, "getSystemService", "(Ljava/lang/String;)Ljava/lang/Object;"); if (!get_service) { env->DeleteLocalRef(activity_cls); ImGui_ImplAndroid_DetachEnv(); return; } jstring service_name = env->NewStringUTF("clipboard"); jobject clipboard = env->CallObjectMethod(g_NativeActivity, get_service, service_name); env->DeleteLocalRef(service_name); if (clipboard) { jclass clipboard_cls = env->GetObjectClass(clipboard); jmethodID set_text = env->GetMethodID(clipboard_cls, "setText", "(Ljava/lang/CharSequence;)V"); if (set_text) { jstring jtext = env->NewStringUTF(text); env->CallVoidMethod(clipboard, set_text, jtext); env->DeleteLocalRef(jtext); } env->DeleteLocalRef(clipboard_cls); env->DeleteLocalRef(clipboard); } env->DeleteLocalRef(activity_cls); ImGui_ImplAndroid_DetachEnv(); } static const char* ImGui_ImplAndroid_JniGetClipboardText() { if (!g_NativeActivity) return nullptr; JNIEnv* env = ImGui_ImplAndroid_GetEnv(); if (!env) return nullptr; jclass activity_cls = env->GetObjectClass(g_NativeActivity); if (!activity_cls) { ImGui_ImplAndroid_DetachEnv(); return nullptr; } jmethodID get_service = env->GetMethodID(activity_cls, "getSystemService", "(Ljava/lang/String;)Ljava/lang/Object;"); if (!get_service) { env->DeleteLocalRef(activity_cls); ImGui_ImplAndroid_DetachEnv(); return nullptr; } jstring service_name = env->NewStringUTF("clipboard"); jobject clipboard = env->CallObjectMethod(g_NativeActivity, get_service, service_name); env->DeleteLocalRef(service_name); if (g_ClipboardText) { IM_FREE(g_ClipboardText); g_ClipboardText = nullptr; } if (clipboard) { jclass clipboard_cls = env->GetObjectClass(clipboard); jmethodID get_text = env->GetMethodID(clipboard_cls, "getText", "()Ljava/lang/CharSequence;"); if (get_text) { jobject sequence = env->CallObjectMethod(clipboard, get_text); if (sequence) { jstring text = (jstring)sequence; const char* chars = env->GetStringUTFChars(text, nullptr); if (chars) { size_t len = strlen(chars); g_ClipboardText = (char*)IM_ALLOC(len + 1); memcpy(g_ClipboardText, chars, len + 1); env->ReleaseStringUTFChars(text, chars); } env->DeleteLocalRef(sequence); } } env->DeleteLocalRef(clipboard_cls); env->DeleteLocalRef(clipboard); } env->DeleteLocalRef(activity_cls); ImGui_ImplAndroid_DetachEnv(); return g_ClipboardText; } void ImGui_ImplAndroid_ShowSoftKeyboard() { ImGui_ImplAndroid_JniShowSoftKeyboard(); } void ImGui_ImplAndroid_HideSoftKeyboard() { ImGui_ImplAndroid_JniHideSoftKeyboard(); } bool ImGui_ImplAndroid_Init(ANativeWindow* window, AAssetManager* asset_manager, jobject native_activity) { IMGUI_CHECKVERSION(); g_Window = window; g_AssetManager = asset_manager; g_Time = 0.0; // Setup backend capabilities flags ImGuiIO& io = ImGui::GetIO(); io.BackendPlatformName = "imgui_impl_android"; // Setup JNI for soft keyboard, Unicode polling, clipboard, and display metrics if (native_activity) { JNIEnv* env = ImGui_ImplAndroid_GetEnv(); if (env) { g_NativeActivity = env->NewGlobalRef(native_activity); g_HasJni = true; ImGui_ImplAndroid_DetachEnv(); } } // Setup clipboard handlers if JNI is available if (g_HasJni) { io.SetClipboardTextFn = [](void* /*user_data*/, const char* text) { ImGui_ImplAndroid_JniSetClipboardText(text); }; io.GetClipboardTextFn = [](void* /*user_data*/) -> const char* { return ImGui_ImplAndroid_JniGetClipboardText(); }; } // Initialize sensor manager (NDK native API, no JNI) // ASensorManager_getInstance() is deprecated in API 26+ but still works. // ASensorManager_getInstanceForPackage() is the modern replacement. #if __ANDROID_API__ >= 26 const char* package_name = "imgui.backend"; g_SensorManager = ASensorManager_getInstanceForPackage(package_name); #else g_SensorManager = ASensorManager_getInstance(); #endif if (g_SensorManager) { // Create the event queue tied to the current thread's looper ALooper* looper = ALooper_forThread(); if (!looper) looper = ALooper_prepare(ALOOPER_PREPARE_ALLOW_NON_CALLBACKS); g_SensorEventQueue = ASensorManager_createEventQueue(g_SensorManager, looper, g_SensorLooperId, nullptr, nullptr); } // Query display metrics via JNI (if activity available) if (g_HasJni) { JNIEnv* env = ImGui_ImplAndroid_GetEnv(); if (env) { jclass activity_cls = env->GetObjectClass(g_NativeActivity); if (activity_cls) { jmethodID get_metrics = env->GetMethodID(activity_cls, "getWindowManager", "()Landroid/view/WindowManager;"); if (get_metrics) { jobject wm = env->CallObjectMethod(g_NativeActivity, get_metrics); if (wm) { jclass wm_cls = env->GetObjectClass(wm); jmethodID get_default_display = env->GetMethodID(wm_cls, "getDefaultDisplay", "()Landroid/view/Display;"); if (get_default_display) { jobject display = env->CallObjectMethod(wm, get_default_display); if (display) { jclass display_cls = env->GetObjectClass(display); // Refresh rate jmethodID get_refresh = env->GetMethodID(display_cls, "getRefreshRate", "()F"); if (get_refresh) g_DisplayMetrics.RefreshRate = env->CallFloatMethod(display, get_refresh); // Orientation (getRotation: 0=portrait, 1=landscape, 2=rev portrait, 3=rev landscape) jmethodID get_rotation = env->GetMethodID(display_cls, "getRotation", "()I"); if (get_rotation) g_DisplayMetrics.Orientation = env->CallIntMethod(display, get_rotation); env->DeleteLocalRef(display_cls); env->DeleteLocalRef(display); } } env->DeleteLocalRef(wm_cls); env->DeleteLocalRef(wm); } } // Display metrics (DPI, density) jmethodID get_resources = env->GetMethodID(activity_cls, "getResources", "()Landroid/content/res/Resources;"); if (get_resources) { jobject res = env->CallObjectMethod(g_NativeActivity, get_resources); if (res) { jclass res_cls = env->GetObjectClass(res); jmethodID get_metrics = env->GetMethodID(res_cls, "getDisplayMetrics", "()Landroid/util/DisplayMetrics;"); if (get_metrics) { jobject dm = env->CallObjectMethod(res, get_metrics); if (dm) { jclass dm_cls = env->GetObjectClass(dm); jfieldID density_dpi = env->GetFieldID(dm_cls, "densityDpi", "I"); jfieldID density = env->GetFieldID(dm_cls, "density", "F"); jfieldID xdpi = env->GetFieldID(dm_cls, "xdpi", "F"); jfieldID ydpi = env->GetFieldID(dm_cls, "ydpi", "F"); jfieldID w_pixels = env->GetFieldID(dm_cls, "widthPixels", "I"); jfieldID h_pixels = env->GetFieldID(dm_cls, "heightPixels", "I"); if (density_dpi) g_DisplayMetrics.DensityDpi = env->GetIntField(dm, density_dpi); if (density) g_DisplayMetrics.Density = env->GetFloatField(dm, density); if (xdpi) g_DisplayMetrics.Xdpi = env->GetFloatField(dm, xdpi); if (ydpi) g_DisplayMetrics.Ydpi = env->GetFloatField(dm, ydpi); if (w_pixels) g_DisplayMetrics.WidthPixels = env->GetIntField(dm, w_pixels); if (h_pixels) g_DisplayMetrics.HeightPixels = env->GetIntField(dm, h_pixels); env->DeleteLocalRef(dm_cls); env->DeleteLocalRef(dm); } } env->DeleteLocalRef(res_cls); env->DeleteLocalRef(res); } } env->DeleteLocalRef(activity_cls); } ImGui_ImplAndroid_DetachEnv(); } } // Fallback display metrics from ANativeWindow if JNI didn't provide them if (g_Window) { int32_t w = ANativeWindow_getWidth(g_Window); int32_t h = ANativeWindow_getHeight(g_Window); if (g_DisplayMetrics.WidthPixels == 0) g_DisplayMetrics.WidthPixels = w; if (g_DisplayMetrics.HeightPixels == 0) g_DisplayMetrics.HeightPixels = h; if (g_DisplayMetrics.DensityDpi == 0) g_DisplayMetrics.DensityDpi = 160; // Default to mdpi if (g_DisplayMetrics.Density == 0.0f) g_DisplayMetrics.Density = (float)g_DisplayMetrics.DensityDpi / 160.0f; if (g_DisplayMetrics.RefreshRate == 0.0f) g_DisplayMetrics.RefreshRate = 60.0f; } return true; } void ImGui_ImplAndroid_Shutdown() { // Disable all sensors and destroy the event queue if (g_SensorManager && g_SensorEventQueue) { for (int i = 0; i < ImGui_ImplAndroid_SensorType_Count; i++) { if (g_SensorEnabled[i] && g_Sensors[i]) { ASensorEventQueue_disableSensor(g_SensorEventQueue, g_Sensors[i]); g_SensorEnabled[i] = false; } g_Sensors[i] = nullptr; g_SensorData[i] = ImGui_ImplAndroid_SensorData{}; } ASensorManager_destroyEventQueue(g_SensorManager, g_SensorEventQueue); g_SensorEventQueue = nullptr; } g_SensorManager = nullptr; ImGuiIO& io = ImGui::GetIO(); io.BackendPlatformName = nullptr; io.SetClipboardTextFn = nullptr; io.GetClipboardTextFn = nullptr; if (g_ClipboardText) { IM_FREE(g_ClipboardText); g_ClipboardText = nullptr; } // Release the global ref to the activity if (g_NativeActivity) { JNIEnv* env = ImGui_ImplAndroid_GetEnv(); if (env) { env->DeleteGlobalRef(g_NativeActivity); g_NativeActivity = nullptr; ImGui_ImplAndroid_DetachEnv(); } } g_HasJni = false; g_JavaVM = nullptr; g_Window = nullptr; g_AssetManager = nullptr; g_DisplayMetrics = ImGui_ImplAndroid_DisplayMetrics{}; } void ImGui_ImplAndroid_NewFrame() { ImGuiIO& io = ImGui::GetIO(); // 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, ¤t_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; // Poll Unicode characters from the Java side (soft keyboard input) if (g_HasJni) { ImGui_ImplAndroid_JniPollUnicodeChars(); // Show/hide soft keyboard based on ImGui's text input requests static bool want_text_input_last = false; if (io.WantTextInput && !want_text_input_last) ImGui_ImplAndroid_JniShowSoftKeyboard(); else if (!io.WantTextInput && want_text_input_last) ImGui_ImplAndroid_JniHideSoftKeyboard(); want_text_input_last = io.WantTextInput; } // Drain sensor events — non-blocking, process all available if (g_SensorEventQueue) { ASensorEvent event; while (ASensorEventQueue_getEvents(g_SensorEventQueue, &event, 1) > 0) { for (int i = 0; i < ImGui_ImplAndroid_SensorType_Count; i++) { if (event.type == g_SensorTypes[i] && g_SensorEnabled[i]) { g_SensorData[i].Values[0] = event.vector.x; g_SensorData[i].Values[1] = event.vector.y; g_SensorData[i].Values[2] = event.vector.z; g_SensorData[i].Accuracy = (float)event.acceleration.status; // Reuse the status field g_SensorData[i].Timestamp = (double)event.timestamp / 1e9; // ns to seconds break; } } } } // Update display size (in case of rotation/resize) g_DisplayMetrics.WidthPixels = (int)io.DisplaySize.x; g_DisplayMetrics.HeightPixels = (int)io.DisplaySize.y; } // --- Sensor API --- bool ImGui_ImplAndroid_IsSensorAvailable(int sensor_type) { if (sensor_type < 0 || sensor_type >= ImGui_ImplAndroid_SensorType_Count) return false; if (!g_SensorManager) return false; if (g_Sensors[sensor_type]) return true; // Try to get the default sensor for this type const ASensor* sensor = ASensorManager_getDefaultSensor(g_SensorManager, g_SensorTypes[sensor_type]); return sensor != nullptr; } bool ImGui_ImplAndroid_EnableSensor(int sensor_type) { if (sensor_type < 0 || sensor_type >= ImGui_ImplAndroid_SensorType_Count) return false; if (!g_SensorManager || !g_SensorEventQueue) return false; if (g_Sensors[sensor_type] == nullptr) { g_Sensors[sensor_type] = ASensorManager_getDefaultSensor(g_SensorManager, g_SensorTypes[sensor_type]); if (!g_Sensors[sensor_type]) return false; // Sensor not present on this device } if (g_SensorEnabled[sensor_type]) return true; // Already enabled int result = ASensorEventQueue_enableSensor(g_SensorEventQueue, g_Sensors[sensor_type]); if (result < 0) return false; // Set a reasonable sampling rate (events per second) // Use the sensor's minimum delay for maximum precision, or ~60Hz int min_delay_us = ASensor_getMinDelay(g_Sensors[sensor_type]); int sampling_period_us = (min_delay_us > 0 && min_delay_us < 16666) ? min_delay_us : 16666; // ~60Hz ASensorEventQueue_setEventRate(g_SensorEventQueue, g_Sensors[sensor_type], sampling_period_us); g_SensorEnabled[sensor_type] = true; g_SensorData[sensor_type].Available = true; return true; } void ImGui_ImplAndroid_DisableSensor(int sensor_type) { if (sensor_type < 0 || sensor_type >= ImGui_ImplAndroid_SensorType_Count) return; if (!g_SensorEventQueue || !g_Sensors[sensor_type] || !g_SensorEnabled[sensor_type]) return; ASensorEventQueue_disableSensor(g_SensorEventQueue, g_Sensors[sensor_type]); g_SensorEnabled[sensor_type] = false; g_SensorData[sensor_type].Available = false; } void ImGui_ImplAndroid_GetSensorData(int sensor_type, ImGui_ImplAndroid_SensorData* out_data) { if (!out_data || sensor_type < 0 || sensor_type >= ImGui_ImplAndroid_SensorType_Count) { if (out_data) *out_data = ImGui_ImplAndroid_SensorData{}; return; } *out_data = g_SensorData[sensor_type]; out_data->Available = g_Sensors[sensor_type] != nullptr; } // --- Display Metrics API --- void ImGui_ImplAndroid_GetDisplayMetrics(ImGui_ImplAndroid_DisplayMetrics* out_metrics) { if (out_metrics) *out_metrics = g_DisplayMetrics; } //----------------------------------------------------------------------------- #endif // #ifndef IMGUI_DISABLE