Make use of OnSystemUiVisibilityChangeListener to check whether navbar is hidden. Affects DPI calculations.

Also recalculate all dp parameters after either display or buffer size changed.

android/jni/app-android.cpp

@@ -611,6 +611,30 @@ extern "C" void Java_org_ppsspp_ppsspp_NativeRenderer_displayInit(JNIEnv * env,
 	NativeMessageReceived("recreateviews", "");
 }
 
+static void recalculateDpi() {
+	g_dpi = display_dpi_x;
+	g_dpi_scale_x = 240.0f / display_dpi_x;
+	g_dpi_scale_y = 240.0f / display_dpi_y;
+	g_dpi_scale_real_x = g_dpi_scale_x;
+	g_dpi_scale_real_y = g_dpi_scale_y;
+
+	dp_xres = display_xres * g_dpi_scale_x;
+	dp_yres = display_yres * g_dpi_scale_y;
+
+	// Touch scaling is from display pixels to dp pixels.
+	// Wait, doesn't even make sense... this is equal to g_dpi_scale_x. TODO: Figure out what's going on!
+	dp_xscale = (float)dp_xres / (float)display_xres;
+	dp_yscale = (float)dp_yres / (float)display_yres;
+
+	pixel_in_dps_x = (float)pixel_xres / dp_xres;
+	pixel_in_dps_y = (float)pixel_yres / dp_yres;
+
+	ILOG("RecalcDPI: g_dpi=%f g_dpi_scale_x=%f g_dpi_scale_y=%f", g_dpi, g_dpi_scale_x, g_dpi_scale_y);
+	ILOG("RecalcDPI: dp_xscale=%f dp_yscale=%f", dp_xscale, dp_yscale);
+	ILOG("RecalcDPI: dp_xres=%d dp_yres=%d", dp_xres, dp_yres);
+	ILOG("RecalcDPI: pixel_xres=%d pixel_yres=%d", pixel_xres, pixel_yres);
+}
+
 extern "C" void JNICALL Java_org_ppsspp_ppsspp_NativeApp_backbufferResize(JNIEnv *, jclass, jint bufw, jint bufh, jint format) {
 	ILOG("NativeApp.backbufferResize(%d x %d)", bufw, bufh);
 
@@ -622,32 +646,13 @@ extern "C" void JNICALL Java_org_ppsspp_ppsspp_NativeApp_backbufferResize(JNIEnv
 	pixel_yres = bufh;
 	backbuffer_format = format;
 
-	g_dpi = display_dpi_x;
+	recalculateDpi();
-	g_dpi_scale_x = 240.0f / g_dpi;
-	g_dpi_scale_y = 240.0f / g_dpi;
-	g_dpi_scale_real_x = g_dpi_scale_x;
-	g_dpi_scale_real_y = g_dpi_scale_y;
-
-	dp_xres = display_xres * g_dpi_scale_x;
-	dp_yres = display_yres * g_dpi_scale_y;
-
-	// Touch scaling is from display pixels to dp pixels.
-	dp_xscale = (float)dp_xres / (float)display_xres;
-	dp_yscale = (float)dp_yres / (float)display_yres;
-
-	pixel_in_dps_x = (float)pixel_xres / dp_xres;
-	pixel_in_dps_y = (float)pixel_yres / dp_yres;
-
-	ILOG("g_dpi=%f g_dpi_scale_x=%f g_dpi_scale_y=%f", g_dpi, g_dpi_scale_x, g_dpi_scale_y);
-	ILOG("dp_xscale=%f dp_yscale=%f", dp_xscale, dp_yscale);
-	ILOG("dp_xres=%d dp_yres=%d", dp_xres, dp_yres);
-	ILOG("pixel_xres=%d pixel_yres=%d", pixel_xres, pixel_yres);
 
 	if (new_size) {
 		ILOG("Size change detected (previously %d,%d) - calling NativeResized()", old_w, old_h);
 		NativeResized();
 	} else {
-		ILOG("NativeApp::backbufferReisze: Size didn't change.");
+		ILOG("NativeApp::backbufferResize: Size didn't change.");
 	}
 }
 
@@ -897,6 +902,8 @@ extern "C" void JNICALL Java_org_ppsspp_ppsspp_NativeApp_setDisplayParameters(JN
 	display_dpi_x = dpi;
 	display_dpi_y = dpi;
 	display_hz = refreshRate;
+
+	recalculateDpi();
 }
 
 extern "C" void JNICALL Java_org_ppsspp_ppsspp_NativeApp_computeDesiredBackbufferDimensions() {

android/src/org/ppsspp/ppsspp/NativeActivity.java

@@ -53,6 +53,8 @@ import java.lang.reflect.Field;
 import java.util.List;
 import java.util.Locale;
 
+import static android.view.View.SYSTEM_UI_FLAG_HIDE_NAVIGATION;
+
 public abstract class NativeActivity extends Activity implements SurfaceHolder.Callback {
 	// Remember to loadLibrary your JNI .so in a static {} block
 
@@ -85,6 +87,8 @@ public abstract class NativeActivity extends Activity implements SurfaceHolder.C
 
 	private boolean sustainedPerfSupported;
 
+	private boolean navigationHidden;
+
 	// audioFocusChangeListener to listen to changes in audio state
 	private AudioFocusChangeListener audioFocusChangeListener;
 	private AudioManager audioManager;
@@ -404,18 +408,20 @@ public abstract class NativeActivity extends Activity implements SurfaceHolder.C
 	@SuppressLint("InlinedApi")
 	@TargetApi(Build.VERSION_CODES.ICE_CREAM_SANDWICH)
 	private void updateSystemUiVisibility() {
+		// Compute our _desired_ systemUiVisibility
 		int flags = 0;
 		if (useLowProfileButtons()) {
 			flags |= View.SYSTEM_UI_FLAG_LOW_PROFILE;
 		}
 		if (useImmersive()) {
-			flags |= View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION;
+			flags |= View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY | SYSTEM_UI_FLAG_HIDE_NAVIGATION;
 		}
 		if (getWindow().getDecorView() != null) {
 			getWindow().getDecorView().setSystemUiVisibility(flags);
 		} else {
 			Log.e(TAG, "updateSystemUiVisibility: decor view not yet created, ignoring");
 		}
+
 		updateDisplayMeasurements();
 	}
 
@@ -457,16 +463,12 @@ public abstract class NativeActivity extends Activity implements SurfaceHolder.C
 		Display display = getWindowManager().getDefaultDisplay();
 
 		DisplayMetrics metrics = new DisplayMetrics();
-		if (useImmersive() && Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1) {
+		if (navigationHidden) {
-			if (Build.VERSION.SDK_INT < Build.VERSION_CODES.N || !isInMultiWindowMode()) {
+			display.getRealMetrics(metrics);
-				display.getRealMetrics(metrics);
-			} else {
-				// multi-window mode
-				display.getMetrics(metrics);
-			}
 		} else {
 			display.getMetrics(metrics);
 		}
+
 		densityDpi = metrics.densityDpi;
 		refreshRate = display.getRefreshRate();
 
@@ -602,6 +604,7 @@ public abstract class NativeActivity extends Activity implements SurfaceHolder.C
 			return;
 		}
 		Log.w(TAG, "Surface changed. Resolution: " + width + "x" + height + " Format: " + format);
+		// The window size might have changed (immersive mode, native fullscreen on some devices)
 		NativeApp.backbufferResize(width, height, format);
 		mSurface = holder.getSurface();
 		if (!javaGL) {
@@ -671,9 +674,14 @@ public abstract class NativeActivity extends Activity implements SurfaceHolder.C
 		getWindow().getDecorView().setOnSystemUiVisibilityChangeListener(new OnSystemUiVisibilityChangeListener() {
 			@Override
 			public void onSystemUiVisibilityChange(int visibility) {
-				if (visibility == 0) {
+				// Called when the system UI's visibility changes, regardless of
-					updateSystemUiVisibility();
+				// whether it's because of our or system actions.
-				}
+				// We will try to force it to follow our preference but will not stupidly
+				// act as if it's visible if it's not.
+				navigationHidden = ((visibility & SYSTEM_UI_FLAG_HIDE_NAVIGATION) != 0);
+				// TODO: Check here if it's the state we want.
+				Log.i(TAG, "SystemUiVisibilityChange! visibility=" + visibility + " navigationHidden: " + navigationHidden);
+				updateDisplayMeasurements();
 			}
 		});
 	}

android/src/org/ppsspp/ppsspp/NativeGLView.java

@@ -116,7 +116,6 @@ public class NativeGLView extends GLSurfaceView implements SensorEventListener,
 
 	@Override
 	public void onPause() {
-		Log.i(TAG, "onPause");
 		super.onPause();
 		mSensorManager.unregisterListener(this);
 		if (mController != null) {
@@ -131,7 +130,6 @@ public class NativeGLView extends GLSurfaceView implements SensorEventListener,
 		mSensorManager.registerListener(this, mAccelerometer, SensorManager.SENSOR_DELAY_GAME);
 		if (mController != null) {
 			mController.onResume();
-
 			// According to the docs, the Moga's state can be inconsistent here.
 			// We should do a one time poll. TODO
 		}

android/src/org/ppsspp/ppsspp/NativeSurfaceView.java

@@ -3,6 +3,7 @@ package org.ppsspp.ppsspp;
 // Touch- and sensor-enabled SurfaceView.
 // Supports simple multitouch and pressure.
 // DPI scaling is handled by the native code.
+// Used by the Vulkan backend (and EGL, but that path is no longer active)
 
 import android.annotation.SuppressLint;
 import android.annotation.TargetApi;
@@ -115,6 +116,7 @@ public class NativeSurfaceView extends SurfaceView implements SensorEventListene
 	}
 
 	public void onPause() {
+		Log.i(TAG, "onPause");
 		mSensorManager.unregisterListener(this);
 		if (mController != null) {
 			mController.onPause();