1// dear imgui: Platform Binding for Android native app
2// This needs to be used along with the OpenGL 3 Renderer (imgui_impl_opengl3)
3
4// Implemented features:
5// [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]
6// [X] Platform: Mouse support. Can discriminate Mouse/TouchScreen/Pen.
7// Missing features or Issues:
8// [ ] Platform: Clipboard support.
9// [ ] Platform: Gamepad support.
10// [ ] Platform: Mouse cursor shape and visibility (ImGuiBackendFlags_HasMouseCursors). Disable with 'io.ConfigFlags |= ImGuiConfigFlags_NoMouseCursorChange'. FIXME: Check if this is even possible with Android.
11// [ ] Platform: Multi-viewport support (multiple windows). Not meaningful on Android.
12// Important:
13// - Consider using SDL or GLFW backend on Android, which will be more full-featured than this.
14// - FIXME: On-screen keyboard currently needs to be enabled by the application (see examples/ and issue #3446)
15// - FIXME: Unicode character inputs needs to be passed by Dear ImGui by the application (see examples/ and issue #3446)
16
17// You can use unmodified imgui_impl_* files in your project. See examples/ folder for examples of using this.
18// Prefer including the entire imgui/ repository into your project (either as a copy or as a submodule), and only build the backends you need.
19// Learn about Dear ImGui:
20// - FAQ https://dearimgui.com/faq
21// - Getting Started https://dearimgui.com/getting-started
22// - Documentation https://dearimgui.com/docs (same as your local docs/ folder).
23// - Introduction, links and more at the top of imgui.cpp
24
25// CHANGELOG
26// (minor and older changes stripped away, please see git history for details)
27// 2022-09-26: Inputs: Renamed ImGuiKey_ModXXX introduced in 1.87 to ImGuiMod_XXX (old names still supported).
28// 2022-01-26: Inputs: replaced short-lived io.AddKeyModsEvent() (added two weeks ago) with io.AddKeyEvent() using ImGuiKey_ModXXX flags. Sorry for the confusion.
29// 2022-01-17: Inputs: calling new io.AddMousePosEvent(), io.AddMouseButtonEvent(), io.AddMouseWheelEvent() API (1.87+).
30// 2022-01-10: Inputs: calling new io.AddKeyEvent(), io.AddKeyModsEvent() + io.SetKeyEventNativeData() API (1.87+). Support for full ImGuiKey range.
31// 2021-03-04: Initial version.
32
33#include "imgui.h"
34#ifndef IMGUI_DISABLE
35#include "imgui_impl_android.h"
36#include <time.h>
37#include <android/native_window.h>
38#include <android/input.h>
39#include <android/keycodes.h>
40#include <android/log.h>
41
42// Android data
43static double g_Time = 0.0;
44static ANativeWindow* g_Window;
45static char g_LogTag[] = "ImGuiExample";
46
47static ImGuiKey ImGui_ImplAndroid_KeyCodeToImGuiKey(int32_t key_code)
48{
49 switch (key_code)
50 {
51 case AKEYCODE_TAB: return ImGuiKey_Tab;
52 case AKEYCODE_DPAD_LEFT: return ImGuiKey_LeftArrow;
53 case AKEYCODE_DPAD_RIGHT: return ImGuiKey_RightArrow;
54 case AKEYCODE_DPAD_UP: return ImGuiKey_UpArrow;
55 case AKEYCODE_DPAD_DOWN: return ImGuiKey_DownArrow;
56 case AKEYCODE_PAGE_UP: return ImGuiKey_PageUp;
57 case AKEYCODE_PAGE_DOWN: return ImGuiKey_PageDown;
58 case AKEYCODE_MOVE_HOME: return ImGuiKey_Home;
59 case AKEYCODE_MOVE_END: return ImGuiKey_End;
60 case AKEYCODE_INSERT: return ImGuiKey_Insert;
61 case AKEYCODE_FORWARD_DEL: return ImGuiKey_Delete;
62 case AKEYCODE_DEL: return ImGuiKey_Backspace;
63 case AKEYCODE_SPACE: return ImGuiKey_Space;
64 case AKEYCODE_ENTER: return ImGuiKey_Enter;
65 case AKEYCODE_ESCAPE: return ImGuiKey_Escape;
66 case AKEYCODE_APOSTROPHE: return ImGuiKey_Apostrophe;
67 case AKEYCODE_COMMA: return ImGuiKey_Comma;
68 case AKEYCODE_MINUS: return ImGuiKey_Minus;
69 case AKEYCODE_PERIOD: return ImGuiKey_Period;
70 case AKEYCODE_SLASH: return ImGuiKey_Slash;
71 case AKEYCODE_SEMICOLON: return ImGuiKey_Semicolon;
72 case AKEYCODE_EQUALS: return ImGuiKey_Equal;
73 case AKEYCODE_LEFT_BRACKET: return ImGuiKey_LeftBracket;
74 case AKEYCODE_BACKSLASH: return ImGuiKey_Backslash;
75 case AKEYCODE_RIGHT_BRACKET: return ImGuiKey_RightBracket;
76 case AKEYCODE_GRAVE: return ImGuiKey_GraveAccent;
77 case AKEYCODE_CAPS_LOCK: return ImGuiKey_CapsLock;
78 case AKEYCODE_SCROLL_LOCK: return ImGuiKey_ScrollLock;
79 case AKEYCODE_NUM_LOCK: return ImGuiKey_NumLock;
80 case AKEYCODE_SYSRQ: return ImGuiKey_PrintScreen;
81 case AKEYCODE_BREAK: return ImGuiKey_Pause;
82 case AKEYCODE_NUMPAD_0: return ImGuiKey_Keypad0;
83 case AKEYCODE_NUMPAD_1: return ImGuiKey_Keypad1;
84 case AKEYCODE_NUMPAD_2: return ImGuiKey_Keypad2;
85 case AKEYCODE_NUMPAD_3: return ImGuiKey_Keypad3;
86 case AKEYCODE_NUMPAD_4: return ImGuiKey_Keypad4;
87 case AKEYCODE_NUMPAD_5: return ImGuiKey_Keypad5;
88 case AKEYCODE_NUMPAD_6: return ImGuiKey_Keypad6;
89 case AKEYCODE_NUMPAD_7: return ImGuiKey_Keypad7;
90 case AKEYCODE_NUMPAD_8: return ImGuiKey_Keypad8;
91 case AKEYCODE_NUMPAD_9: return ImGuiKey_Keypad9;
92 case AKEYCODE_NUMPAD_DOT: return ImGuiKey_KeypadDecimal;
93 case AKEYCODE_NUMPAD_DIVIDE: return ImGuiKey_KeypadDivide;
94 case AKEYCODE_NUMPAD_MULTIPLY: return ImGuiKey_KeypadMultiply;
95 case AKEYCODE_NUMPAD_SUBTRACT: return ImGuiKey_KeypadSubtract;
96 case AKEYCODE_NUMPAD_ADD: return ImGuiKey_KeypadAdd;
97 case AKEYCODE_NUMPAD_ENTER: return ImGuiKey_KeypadEnter;
98 case AKEYCODE_NUMPAD_EQUALS: return ImGuiKey_KeypadEqual;
99 case AKEYCODE_CTRL_LEFT: return ImGuiKey_LeftCtrl;
100 case AKEYCODE_SHIFT_LEFT: return ImGuiKey_LeftShift;
101 case AKEYCODE_ALT_LEFT: return ImGuiKey_LeftAlt;
102 case AKEYCODE_META_LEFT: return ImGuiKey_LeftSuper;
103 case AKEYCODE_CTRL_RIGHT: return ImGuiKey_RightCtrl;
104 case AKEYCODE_SHIFT_RIGHT: return ImGuiKey_RightShift;
105 case AKEYCODE_ALT_RIGHT: return ImGuiKey_RightAlt;
106 case AKEYCODE_META_RIGHT: return ImGuiKey_RightSuper;
107 case AKEYCODE_MENU: return ImGuiKey_Menu;
108 case AKEYCODE_0: return ImGuiKey_0;
109 case AKEYCODE_1: return ImGuiKey_1;
110 case AKEYCODE_2: return ImGuiKey_2;
111 case AKEYCODE_3: return ImGuiKey_3;
112 case AKEYCODE_4: return ImGuiKey_4;
113 case AKEYCODE_5: return ImGuiKey_5;
114 case AKEYCODE_6: return ImGuiKey_6;
115 case AKEYCODE_7: return ImGuiKey_7;
116 case AKEYCODE_8: return ImGuiKey_8;
117 case AKEYCODE_9: return ImGuiKey_9;
118 case AKEYCODE_A: return ImGuiKey_A;
119 case AKEYCODE_B: return ImGuiKey_B;
120 case AKEYCODE_C: return ImGuiKey_C;
121 case AKEYCODE_D: return ImGuiKey_D;
122 case AKEYCODE_E: return ImGuiKey_E;
123 case AKEYCODE_F: return ImGuiKey_F;
124 case AKEYCODE_G: return ImGuiKey_G;
125 case AKEYCODE_H: return ImGuiKey_H;
126 case AKEYCODE_I: return ImGuiKey_I;
127 case AKEYCODE_J: return ImGuiKey_J;
128 case AKEYCODE_K: return ImGuiKey_K;
129 case AKEYCODE_L: return ImGuiKey_L;
130 case AKEYCODE_M: return ImGuiKey_M;
131 case AKEYCODE_N: return ImGuiKey_N;
132 case AKEYCODE_O: return ImGuiKey_O;
133 case AKEYCODE_P: return ImGuiKey_P;
134 case AKEYCODE_Q: return ImGuiKey_Q;
135 case AKEYCODE_R: return ImGuiKey_R;
136 case AKEYCODE_S: return ImGuiKey_S;
137 case AKEYCODE_T: return ImGuiKey_T;
138 case AKEYCODE_U: return ImGuiKey_U;
139 case AKEYCODE_V: return ImGuiKey_V;
140 case AKEYCODE_W: return ImGuiKey_W;
141 case AKEYCODE_X: return ImGuiKey_X;
142 case AKEYCODE_Y: return ImGuiKey_Y;
143 case AKEYCODE_Z: return ImGuiKey_Z;
144 case AKEYCODE_F1: return ImGuiKey_F1;
145 case AKEYCODE_F2: return ImGuiKey_F2;
146 case AKEYCODE_F3: return ImGuiKey_F3;
147 case AKEYCODE_F4: return ImGuiKey_F4;
148 case AKEYCODE_F5: return ImGuiKey_F5;
149 case AKEYCODE_F6: return ImGuiKey_F6;
150 case AKEYCODE_F7: return ImGuiKey_F7;
151 case AKEYCODE_F8: return ImGuiKey_F8;
152 case AKEYCODE_F9: return ImGuiKey_F9;
153 case AKEYCODE_F10: return ImGuiKey_F10;
154 case AKEYCODE_F11: return ImGuiKey_F11;
155 case AKEYCODE_F12: return ImGuiKey_F12;
156 default: return ImGuiKey_None;
157 }
158}
159
160int32_t ImGui_ImplAndroid_HandleInputEvent(const AInputEvent* input_event)
161{
162 ImGuiIO& io = ImGui::GetIO();
163 int32_t event_type = AInputEvent_getType(input_event);
164 switch (event_type)
165 {
166 case AINPUT_EVENT_TYPE_KEY:
167 {
168 int32_t event_key_code = AKeyEvent_getKeyCode(input_event);
169 int32_t event_scan_code = AKeyEvent_getScanCode(input_event);
170 int32_t event_action = AKeyEvent_getAction(input_event);
171 int32_t event_meta_state = AKeyEvent_getMetaState(input_event);
172
173 io.AddKeyEvent(ImGuiMod_Ctrl, (event_meta_state & AMETA_CTRL_ON) != 0);
174 io.AddKeyEvent(ImGuiMod_Shift, (event_meta_state & AMETA_SHIFT_ON) != 0);
175 io.AddKeyEvent(ImGuiMod_Alt, (event_meta_state & AMETA_ALT_ON) != 0);
176 io.AddKeyEvent(ImGuiMod_Super, (event_meta_state & AMETA_META_ON) != 0);
177
178 switch (event_action)
179 {
180 // FIXME: AKEY_EVENT_ACTION_DOWN and AKEY_EVENT_ACTION_UP occur at once as soon as a touch pointer
181 // goes up from a key. We use a simple key event queue/ and process one event per key per frame in
182 // ImGui_ImplAndroid_NewFrame()...or consider using IO queue, if suitable: https://github.com/ocornut/imgui/issues/2787
183 case AKEY_EVENT_ACTION_DOWN:
184 case AKEY_EVENT_ACTION_UP:
185 {
186 ImGuiKey key = ImGui_ImplAndroid_KeyCodeToImGuiKey(event_key_code);
187 if (key != ImGuiKey_None)
188 {
189 io.AddKeyEvent(key, event_action == AKEY_EVENT_ACTION_DOWN);
190 io.SetKeyEventNativeData(key, native_keycode: event_key_code, native_scancode: event_scan_code);
191 }
192
193 break;
194 }
195 default:
196 break;
197 }
198 break;
199 }
200 case AINPUT_EVENT_TYPE_MOTION:
201 {
202 int32_t event_action = AMotionEvent_getAction(input_event);
203 int32_t event_pointer_index = (event_action & AMOTION_EVENT_ACTION_POINTER_INDEX_MASK) >> AMOTION_EVENT_ACTION_POINTER_INDEX_SHIFT;
204 event_action &= AMOTION_EVENT_ACTION_MASK;
205
206 switch (AMotionEvent_getToolType(input_event, event_pointer_index))
207 {
208 case AMOTION_EVENT_TOOL_TYPE_MOUSE:
209 io.AddMouseSourceEvent(source: ImGuiMouseSource_Mouse);
210 break;
211 case AMOTION_EVENT_TOOL_TYPE_STYLUS:
212 case AMOTION_EVENT_TOOL_TYPE_ERASER:
213 io.AddMouseSourceEvent(source: ImGuiMouseSource_Pen);
214 break;
215 case AMOTION_EVENT_TOOL_TYPE_FINGER:
216 default:
217 io.AddMouseSourceEvent(source: ImGuiMouseSource_TouchScreen);
218 break;
219 }
220
221 switch (event_action)
222 {
223 case AMOTION_EVENT_ACTION_DOWN:
224 case AMOTION_EVENT_ACTION_UP:
225 {
226 // Physical mouse buttons (and probably other physical devices) also invoke the actions AMOTION_EVENT_ACTION_DOWN/_UP,
227 // but we have to process them separately to identify the actual button pressed. This is done below via
228 // AMOTION_EVENT_ACTION_BUTTON_PRESS/_RELEASE. Here, we only process "FINGER" input (and "UNKNOWN", as a fallback).
229 int tool_type = AMotionEvent_getToolType(input_event, event_pointer_index);
230 if (tool_type == AMOTION_EVENT_TOOL_TYPE_FINGER || tool_type == AMOTION_EVENT_TOOL_TYPE_UNKNOWN)
231 {
232 io.AddMousePosEvent(x: AMotionEvent_getX(input_event, event_pointer_index), y: AMotionEvent_getY(input_event, event_pointer_index));
233 io.AddMouseButtonEvent(0, event_action == AMOTION_EVENT_ACTION_DOWN);
234 }
235 break;
236 }
237 case AMOTION_EVENT_ACTION_BUTTON_PRESS:
238 case AMOTION_EVENT_ACTION_BUTTON_RELEASE:
239 {
240 int32_t button_state = AMotionEvent_getButtonState(input_event);
241 io.AddMouseButtonEvent(0, (button_state & AMOTION_EVENT_BUTTON_PRIMARY) != 0);
242 io.AddMouseButtonEvent(1, (button_state & AMOTION_EVENT_BUTTON_SECONDARY) != 0);
243 io.AddMouseButtonEvent(2, (button_state & AMOTION_EVENT_BUTTON_TERTIARY) != 0);
244 break;
245 }
246 case AMOTION_EVENT_ACTION_HOVER_MOVE: // Hovering: Tool moves while NOT pressed (such as a physical mouse)
247 case AMOTION_EVENT_ACTION_MOVE: // Touch pointer moves while DOWN
248 io.AddMousePosEvent(x: AMotionEvent_getX(input_event, event_pointer_index), y: AMotionEvent_getY(input_event, event_pointer_index));
249 break;
250 case AMOTION_EVENT_ACTION_SCROLL:
251 io.AddMouseWheelEvent(AMotionEvent_getAxisValue(input_event, AMOTION_EVENT_AXIS_HSCROLL, event_pointer_index), AMotionEvent_getAxisValue(input_event, AMOTION_EVENT_AXIS_VSCROLL, event_pointer_index));
252 break;
253 default:
254 break;
255 }
256 }
257 return 1;
258 default:
259 break;
260 }
261
262 return 0;
263}
264
265bool ImGui_ImplAndroid_Init(ANativeWindow* window)
266{
267 IMGUI_CHECKVERSION();
268
269 g_Window = window;
270 g_Time = 0.0;
271
272 // Setup backend capabilities flags
273 ImGuiIO& io = ImGui::GetIO();
274 io.BackendPlatformName = "imgui_impl_android";
275
276 return true;
277}
278
279void ImGui_ImplAndroid_Shutdown()
280{
281 ImGuiIO& io = ImGui::GetIO();
282 io.BackendPlatformName = nullptr;
283}
284
285void ImGui_ImplAndroid_NewFrame()
286{
287 ImGuiIO& io = ImGui::GetIO();
288
289 // Setup display size (every frame to accommodate for window resizing)
290 int32_t window_width = ANativeWindow_getWidth(g_Window);
291 int32_t window_height = ANativeWindow_getHeight(g_Window);
292 int display_width = window_width;
293 int display_height = window_height;
294
295 io.DisplaySize = ImVec2((float)window_width, (float)window_height);
296 if (window_width > 0 && window_height > 0)
297 io.DisplayFramebufferScale = ImVec2((float)display_width / window_width, (float)display_height / window_height);
298
299 // Setup time step
300 struct timespec current_timespec;
301 clock_gettime(CLOCK_MONOTONIC, tp: &current_timespec);
302 double current_time = (double)(current_timespec.tv_sec) + (current_timespec.tv_nsec / 1000000000.0);
303 io.DeltaTime = g_Time > 0.0 ? (float)(current_time - g_Time) : (float)(1.0f / 60.0f);
304 g_Time = current_time;
305}
306
307//-----------------------------------------------------------------------------
308
309#endif // #ifndef IMGUI_DISABLE
310

source code of imgui/backends/imgui_impl_android.cpp