ANDROID: prevent display when paused

Author: chrisws

src/platform/android/app/src/main/java/net/sourceforge/smallbasic/MainActivity.java

@@ -102,6 +102,7 @@ public class MainActivity extends NativeActivity {
     System.loadLibrary("smallbasic");
   }
 
+  public static native void onActivityPaused(boolean paused);
   public static native void onResize(int width, int height);
   public static native void onUnicodeChar(int ch);
   public static native boolean optionSelected(int index);
@@ -600,6 +601,18 @@ protected void onCreate(Bundle savedInstanceState) {
     checkFilePermission();
   }
 
+  @Override
+  protected void onPause() {
+    super.onPause();
+    onActivityPaused(true);
+  }
+
+  @Override
+  protected void onResume() {
+    super.onResume();
+    onActivityPaused(false);
+  }
+
   @Override
   protected void onStop() {
     super.onStop();

src/platform/android/jni/display.cpp

@@ -118,7 +118,8 @@ Graphics::Graphics(android_app *app) : ui::Graphics(),
   _fontBufferB(NULL),
   _app(app),
   _w(0),
-  _h(0) {
+  _h(0),
+  _paused(false) {
 }
 
 Graphics::~Graphics() {
@@ -154,7 +155,7 @@ bool Graphics::construct(int fontId) {
 }
 
 void Graphics::redraw() {
-  if (_app->window != NULL) {
+  if (_app->window != NULL && !_paused) {
     ANativeWindow_Buffer buffer;
     if (ANativeWindow_lock(_app->window, &buffer, NULL) < 0) {
       trace("Unable to lock window buffer");

src/platform/android/jni/display.h

@@ -25,6 +25,7 @@ struct Graphics : ui::Graphics {
   bool construct(int fontId);
   void redraw();
   void resize();
+  void onPaused(bool paused) { _paused=paused; }
   void setSize(int w, int h) { _w = w; _h = h; }
 
 private:
@@ -35,6 +36,7 @@ struct Graphics : ui::Graphics {
   FT_Byte *_fontBufferB;
   android_app *_app;
   int _w, _h;
+  bool _paused;
 };
 
 #endif

src/platform/android/jni/runtime.cpp

@@ -130,6 +130,14 @@ int get_sensor_events(int fd, int events, void *data) {
   return 1;
 }
 
+extern "C" JNIEXPORT void JNICALL Java_net_sourceforge_smallbasic_MainActivity_onActivityPaused
+  (JNIEnv *env, jclass jclazz, jboolean paused) {
+  if (runtime != NULL && !runtime->isClosing() && runtime->isActive() && os_graphics) {
+    trace("paused=%d", paused);
+    runtime->onPaused(paused);
+  }
+}
+
 // callback from MainActivity.java
 extern "C" JNIEXPORT jboolean JNICALL Java_net_sourceforge_smallbasic_MainActivity_optionSelected
   (JNIEnv *env, jclass jclazz, jint index) {

src/platform/android/jni/runtime.h

@@ -66,6 +66,7 @@ struct Runtime : public System {
   void share(const char *path) { setString("share", path); }
   void showCursor(CursorType cursorType) {}
   void showKeypad(bool show);
+  void onPaused(bool paused) { if (_graphics != NULL) _graphics->onPaused(paused); }
   void onResize(int w, int h);
   void onUnicodeChar(int ch);
   void loadConfig();