1 # This file is part of NIT (http://www.nitlanguage.org).
3 # Licensed under the Apache License, Version 2.0 (the "License");
4 # you may not use this file except in compliance with the License.
5 # You may obtain a copy of the License at
7 # http://www.apache.org/licenses/LICENSE-2.0
9 # Unless required by applicable law or agreed to in writing, software
10 # distributed under the License is distributed on an "AS IS" BASIS,
11 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12 # See the License for the specific language governing permissions and
13 # limitations under the License.
15 # Some documentation of this module has been adapted from the
16 # Android Open Source Project.
18 # Core implementation of `app.nit` on Android using a custom Java entry point
20 # This module is implemented in 3 languages:
22 # * The Java code, in `NitActivity.java` acts as the entry point registered
23 # to the Android OS. It relays most of the Android callbacks to C.
24 # In theory, there may be more than one instance of `NitActivity` alive at
25 # a given time. They hold a reference to the corresponding Nit `Activity`
26 # in the attribute `nitActivity`.
28 # * The C code is defined in the top part of this source file. It acts as a
29 # glue between Java and Nit by relaying calls between both languages.
30 # It keeps a global variables reference to the Java VM and the Nit `App`.
32 # * The Nit code defines the `Activity` class with the callbacks from Android.
33 # The callback methods should be redefined by user modules.
35 # The main is invoked when the native library is dynamically linked by
36 # the Java virtual machine. For this reason, the main _must_ execute quickly,
37 # on the main UI thread at least.
38 module nit_activity
is
39 extra_java_files
"NitActivity.java"
40 android_activity
"nit.app.NitActivity"
52 #include <android/log.h>
54 // Nit's App running instance
57 // Java VM that launched this program
60 // JNI callback on loading this program
61 jint JNI_OnLoad(JavaVM *vm, void *reserved) {
62 // Set aside the Java VM
65 // Invoke Nit system and main
68 return JNI_VERSION_1_2;
72 * Implementations of NitActivity.java native methods
75 JNIEXPORT jint JNICALL Java_nit_app_NitActivity_nitRegisterActivity
76 (JNIEnv *env, jobject java_activity)
78 Activity nit_activity = App_register_activity(global_app, java_activity);
79 Activity_incr_ref(nit_activity);
80 return (jint)(void*)nit_activity;
83 JNIEXPORT void JNICALL Java_nit_app_NitActivity_nitOnCreate
84 (JNIEnv *env, jobject java_activity, jint nit_activity, jobject saved_state)
86 Activity_on_create((Activity)nit_activity, saved_state);
89 JNIEXPORT void JNICALL Java_nit_app_NitActivity_nitOnStart
90 (JNIEnv *env, jobject java_activity, jint nit_activity)
92 Activity_on_start((Activity)nit_activity);
95 JNIEXPORT void JNICALL Java_nit_app_NitActivity_nitOnRestart
96 (JNIEnv *env, jobject java_activity, jint nit_activity)
98 Activity_on_restart((Activity)nit_activity);
101 JNIEXPORT void JNICALL Java_nit_app_NitActivity_nitOnResume
102 (JNIEnv *env, jobject java_activity, jint nit_activity)
104 Activity_on_resume((Activity)nit_activity);
107 JNIEXPORT void JNICALL Java_nit_app_NitActivity_nitOnPause
108 (JNIEnv *env, jobject java_activity, jint nit_activity)
110 Activity_on_pause((Activity)nit_activity);
113 JNIEXPORT void JNICALL Java_nit_app_NitActivity_nitOnStop
114 (JNIEnv *env, jobject java_activity, jint nit_activity)
116 Activity_on_stop((Activity)nit_activity);
119 JNIEXPORT void JNICALL Java_nit_app_NitActivity_nitOnDestroy
120 (JNIEnv *env, jobject java_activity, jint nit_activity)
122 Activity_on_destroy((Activity)nit_activity);
125 JNIEXPORT void JNICALL Java_nit_app_NitActivity_nitOnSaveInstanceState
126 (JNIEnv *env, jobject java_activity, jint nit_activity, jobject saved_state)
128 Activity_on_save_instance_state((Activity)nit_activity, saved_state);
131 JNIEXPORT void JNICALL Java_nit_app_NitActivity_nitOnRestoreInstanceState
132 (JNIEnv *env, jobject java_activity, jint nit_activity, jobject saved_state)
134 Activity_on_restore_instance_state((Activity)nit_activity, saved_state);
138 # Wrapper to our Java `NitActivity`
139 extern class NativeNitActivity in "Java" `{ nit.app.NitActivity `}
144 redef fun jvm `{ return global_jvm; `}
149 var activities
= new Array[Activity]
151 # The main Java Activity of this application
152 redef fun native_activity
do return activities
.first
.native
154 redef fun setup
do set_global_app
157 private fun set_global_app
import register_activity
,
158 Activity.on_create
, Activity.on_destroy
,
159 Activity.on_start
, Activity.on_restart
, Activity.on_stop
,
160 Activity.on_pause
, Activity.on_resume
,
161 Activity.on_save_instance_state
, Activity.on_restore_instance_state
`{
166 # Create the Nit side to this new `native` Java activity, and return it to Java
167 private fun register_activity
(native
: NativeNitActivity): Activity
169 native
= native
.new_global_ref
170 var activity
= new Activity(native
)
171 activities
.add activity
176 # An Android activity
178 # You must implement the callbacks (prefixed with `on_`) to follow the
179 # standard Android life-cycle.
181 # Native Java activity
182 var native
: NativeActivity
184 # Notification from Android, the activity is created
186 # Do your normal static set up here.
188 # If available, `save_state` contains the activity's previous state
189 # as registered by `on_save_instance_state`.
191 # Followed by `on_start`.
192 fun on_create
(save_state
: NativeBundle)
198 # Notification from Android, the activity has been restarted
200 # Followed by `on_start`.
201 fun on_restart
do end
203 # Notification from Android, the activity has been started
205 # Followed by `on_resume` or `on_stop`.
206 fun on_start
do app
.on_start
208 # Notification from Android, the activity has been resumed
210 # Followed by `on_pause`
211 fun on_resume
do app
.on_resume
213 # Notification from Android, the activity has been paused
215 # Followed by `on_resume` or `on_stop`.
216 fun on_pause
do app
.on_pause
218 # Notification from Android, the activity has been stopped
220 # Followed by `on_restart` or `on_destroy`.
221 fun on_stop
do app
.on_stop
223 # Notification from Android, the activity is being destroyed
230 native
.delete_global_ref
231 app
.activities
.remove
self
234 # Notification from Android, the activity is being re-initialized from a `save_state`
236 # Occurs after `on_start`.
237 fun on_restore_instance_state
(save_state
: NativeBundle) do end
239 # Notification from Android, the activity may be stopped, save state
241 # Occurs before `on_stop` and, without guarantee, before or after `on_pause`.
242 fun on_save_instance_state
(save_state
: NativeBundle) do app
.on_save_state
244 # Notification from Android, the system is running low on memory
246 # Try to reduce your memory use.
247 fun on_low_memory
do end
249 # Notification from Android, the current window of the activity has lost or gained focus
250 fun on_window_focus_changed
(has_focus
: Bool) do end
252 # Notification from Android, the current device configuration has changed
253 fun on_configuration_changed
do end
256 # Set up global data in C and leave it to Android to callback Java, which we relay to Nit