Add second screen touchpad for dual-display Android devices

backends/platform/android/org/scummvm/scummvm/ScummVMActivity.java

@@ -130,6 +130,8 @@ public class ScummVMActivity extends Activity implements OnKeyboardVisibilityLis
 	private GridLayout _buttonLayout = null;
 	private ImageView _toggleTouchModeKeyboardBtnIcon = null;
 	private ImageView _openMenuBtnIcon = null;
+	private ImageView _toggleSecondScreenBtnIcon = null;
+	private SecondScreenManager _secondScreenManager = null;
 	private LedView _ioLed = null;
 	private int _layoutOrientation;
 
@@ -697,6 +699,22 @@ public void run() {
 		}
 	};
 
+	public final View.OnClickListener secondScreenBtnOnClickListener = new View.OnClickListener() {
+		@Override
+		public void onClick(View v) {
+			runOnUiThread(new Runnable() {
+				public void run() {
+					if (_secondScreenManager != null) {
+						boolean enabled = _secondScreenManager.toggle();
+						if (_toggleSecondScreenBtnIcon != null) {
+							_toggleSecondScreenBtnIcon.setAlpha(enabled ? 1.0f : 0.4f);
+						}
+					}
+				}
+			});
+		}
+	};
+
 	private class MyScummVM extends ScummVM {
 
 		public MyScummVM(SurfaceHolder holder, final MyScummVMDestroyedCallback destroyedCallback) {
@@ -1113,6 +1131,21 @@ public void handle(int exitResult) {
 		_toggleTouchModeKeyboardBtnIcon.setOnLongClickListener(touchModeKeyboardBtnOnLongClickListener);
 		_openMenuBtnIcon.setOnClickListener(menuBtnOnClickListener);
 
+		// Second screen touchpad support (API 17+)
+		_toggleSecondScreenBtnIcon = findViewById(R.id.toggle_second_screen_button);
+		if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.JELLY_BEAN_MR1) {
+			_secondScreenManager = new SecondScreenManager(this, _scummvm);
+			_secondScreenManager.start();
+			if (_secondScreenManager.hasSecondaryDisplay()) {
+				_toggleSecondScreenBtnIcon.setVisibility(View.VISIBLE);
+				_toggleSecondScreenBtnIcon.setOnClickListener(secondScreenBtnOnClickListener);
+			} else {
+				_toggleSecondScreenBtnIcon.setVisibility(View.GONE);
+			}
+		} else {
+			_toggleSecondScreenBtnIcon.setVisibility(View.GONE);
+		}
+
 		// Keyboard visibility listener - mainly to hide system UI if keyboard is shown and we return from Suspend to the Activity
 		setKeyboardVisibilityListener(this);
 
@@ -1260,6 +1293,11 @@ public void onDestroy() {
 			hideScreenKeyboard();
 		}
 
+		if (_secondScreenManager != null) {
+			_secondScreenManager.stop();
+			_secondScreenManager = null;
+		}
+
 		if (_events != null) {
 			_finishing = true;
 

backends/platform/android/org/scummvm/scummvm/SecondScreenHelper.java

@@ -0,0 +1,86 @@
+package org.scummvm.scummvm;
+
+import android.app.Activity;
+import android.app.Application;
+import android.os.Build;
+import android.os.Bundle;
+import android.util.DisplayMetrics;
+import android.view.View;
+import android.view.WindowManager;
+import android.widget.ImageView;
+
+public class SecondScreenHelper {
+
+	private static SecondScreenManager sManager;
+	private static ImageView sToggleBtn;
+	private static Application.ActivityLifecycleCallbacks sLifecycleCallbacks;
+
+	public static void init(Activity activity, ScummVM scummvm) {
+		if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN_MR1) return;
+
+		DisplayMetrics dm = new DisplayMetrics();
+		WindowManager wm = (WindowManager) activity.getSystemService(Activity.WINDOW_SERVICE);
+		if (wm != null) {
+			wm.getDefaultDisplay().getRealMetrics(dm);
+		}
+		int screenW = Math.max(dm.widthPixels, dm.heightPixels);
+		int screenH = Math.min(dm.widthPixels, dm.heightPixels);
+
+		sManager = new SecondScreenManager(activity, scummvm, screenW, screenH);
+		sManager.start();
+
+		int btnId = activity.getResources().getIdentifier(
+			"toggle_second_screen_button", "id", activity.getPackageName());
+		if (btnId != 0) {
+			sToggleBtn = activity.findViewById(btnId);
+		}
+
+		if (sToggleBtn != null && sManager.hasSecondaryDisplay()) {
+			sToggleBtn.setVisibility(View.VISIBLE);
+			sToggleBtn.setAlpha(1.0f);
+			sToggleBtn.setOnClickListener(new View.OnClickListener() {
+				@Override
+				public void onClick(View v) {
+					if (sManager != null) {
+						boolean enabled = sManager.toggle();
+						if (sToggleBtn != null) {
+							sToggleBtn.setAlpha(enabled ? 1.0f : 0.4f);
+						}
+					}
+				}
+			});
+
+			sManager.toggle();
+
+			sLifecycleCallbacks = new Application.ActivityLifecycleCallbacks() {
+				@Override public void onActivityCreated(Activity a, Bundle s) {}
+				@Override public void onActivityStarted(Activity a) {}
+				@Override
+				public void onActivityResumed(Activity a) {
+					if (a instanceof ScummVMActivity && sManager != null) {
+						sManager.onResume();
+					}
+				}
+				@Override
+				public void onActivityPaused(Activity a) {
+					if (a instanceof ScummVMActivity && sManager != null) {
+						sManager.onPause();
+					}
+				}
+				@Override public void onActivityStopped(Activity a) {}
+				@Override public void onActivitySaveInstanceState(Activity a, Bundle o) {}
+				@Override public void onActivityDestroyed(Activity a) {}
+			};
+			activity.getApplication().registerActivityLifecycleCallbacks(sLifecycleCallbacks);
+		}
+	}
+
+	public static void destroy() {
+		if (sManager != null) {
+			sManager.stop();
+			sManager = null;
+		}
+		sToggleBtn = null;
+		sLifecycleCallbacks = null;
+	}
+}

backends/platform/android/org/scummvm/scummvm/SecondScreenInitializer.java

@@ -0,0 +1,78 @@
+package org.scummvm.scummvm;
+
+import android.app.Activity;
+import android.app.Application;
+import android.os.Build;
+import android.os.Bundle;
+import android.view.View;
+import android.widget.ImageView;
+
+import androidx.annotation.RequiresApi;
+
+@RequiresApi(api = Build.VERSION_CODES.ICE_CREAM_SANDWICH)
+public class SecondScreenInitializer implements Application.ActivityLifecycleCallbacks {
+
+	private SecondScreenManager _manager;
+	private ImageView _toggleBtn;
+
+	@Override
+	public void onActivityCreated(Activity activity, Bundle savedInstanceState) {
+		if (!(activity instanceof ScummVMActivity)) return;
+		if (Build.VERSION.SDK_INT < Build.VERSION_CODES.JELLY_BEAN_MR1) return;
+
+		ScummVMActivity svm = (ScummVMActivity) activity;
+
+		try {
+			java.lang.reflect.Field field = ScummVMActivity.class.getDeclaredField("_scummvm");
+			field.setAccessible(true);
+			ScummVM scummvm = (ScummVM) field.get(svm);
+			if (scummvm == null) return;
+
+			_manager = new SecondScreenManager(activity, scummvm);
+			_manager.start();
+
+			_toggleBtn = activity.findViewById(
+				activity.getResources().getIdentifier(
+					"toggle_second_screen_button", "id", activity.getPackageName()));
+
+			if (_toggleBtn != null && _manager.hasSecondaryDisplay()) {
+				_toggleBtn.setVisibility(View.VISIBLE);
+				_toggleBtn.setOnClickListener(new View.OnClickListener() {
+					@Override
+					public void onClick(View v) {
+						if (_manager != null) {
+							boolean enabled = _manager.toggle();
+							_toggleBtn.setAlpha(enabled ? 1.0f : 0.4f);
+						}
+					}
+				});
+			}
+		} catch (Exception e) {
+			// _scummvm field not accessible or not yet initialized
+		}
+	}
+
+	@Override
+	public void onActivityStarted(Activity activity) {}
+
+	@Override
+	public void onActivityResumed(Activity activity) {}
+
+	@Override
+	public void onActivityPaused(Activity activity) {}
+
+	@Override
+	public void onActivityStopped(Activity activity) {}
+
+	@Override
+	public void onActivitySaveInstanceState(Activity activity, Bundle outState) {}
+
+	@Override
+	public void onActivityDestroyed(Activity activity) {
+		if (!(activity instanceof ScummVMActivity)) return;
+		if (_manager != null) {
+			_manager.stop();
+			_manager = null;
+		}
+	}
+}

backends/platform/android/org/scummvm/scummvm/SecondScreenManager.java

@@ -0,0 +1,134 @@
+package org.scummvm.scummvm;
+
+import android.content.Context;
+import android.hardware.display.DisplayManager;
+import android.os.Build;
+import android.os.Handler;
+import android.os.Looper;
+import android.view.Display;
+
+import androidx.annotation.RequiresApi;
+
+@RequiresApi(api = Build.VERSION_CODES.JELLY_BEAN_MR1)
+public class SecondScreenManager {
+
+	private final Context _context;
+	private final ScummVM _scummvm;
+	private final DisplayManager _displayManager;
+	private final int _mainScreenWidth;
+	private final int _mainScreenHeight;
+	private SecondScreenPresentation _presentation;
+	private DisplayManager.DisplayListener _displayListener;
+	private boolean _enabled = false;
+
+	public SecondScreenManager(Context context, ScummVM scummvm, int mainScreenWidth, int mainScreenHeight) {
+		_context = context;
+		_scummvm = scummvm;
+		_displayManager = (DisplayManager) context.getSystemService(Context.DISPLAY_SERVICE);
+		_mainScreenWidth = mainScreenWidth;
+		_mainScreenHeight = mainScreenHeight;
+	}
+
+	public void start() {
+		if (_displayManager == null) return;
+
+		_displayListener = new DisplayManager.DisplayListener() {
+			@Override
+			public void onDisplayAdded(int displayId) {
+				if (_enabled) {
+					tryShowPresentation();
+				}
+			}
+
+			@Override
+			public void onDisplayRemoved(int displayId) {
+				dismissPresentation();
+			}
+
+			@Override
+			public void onDisplayChanged(int displayId) {
+			}
+		};
+
+		_displayManager.registerDisplayListener(_displayListener,
+			new Handler(Looper.getMainLooper()));
+	}
+
+	public void stop() {
+		dismissPresentation();
+		if (_displayManager != null && _displayListener != null) {
+			_displayManager.unregisterDisplayListener(_displayListener);
+			_displayListener = null;
+		}
+	}
+
+	public boolean toggle() {
+		_enabled = !_enabled;
+		if (_enabled) {
+			tryShowPresentation();
+		} else {
+			dismissPresentation();
+		}
+		return _enabled;
+	}
+
+	public boolean isEnabled() {
+		return _enabled;
+	}
+
+	public boolean hasSecondaryDisplay() {
+		return findPresentationDisplay() != null;
+	}
+
+	public void onPause() {
+		dismissPresentation();
+	}
+
+	public void onResume() {
+		if (_enabled) {
+			tryShowPresentation();
+		}
+	}
+
+	private void tryShowPresentation() {
+		Display display = findPresentationDisplay();
+		if (display != null) {
+			showPresentation(display);
+		}
+	}
+
+	private void showPresentation(Display display) {
+		dismissPresentation();
+		try {
+			_presentation = new SecondScreenPresentation(
+				_context, display, _scummvm, _mainScreenWidth, _mainScreenHeight);
+			_presentation.show();
+		} catch (Exception e) {
+			_presentation = null;
+		}
+	}
+
+	private void dismissPresentation() {
+		if (_presentation != null) {
+			try {
+				_presentation.dismiss();
+			} catch (Exception ignored) {
+			}
+			_presentation = null;
+		}
+	}
+
+	private Display findPresentationDisplay() {
+		if (_displayManager == null) return null;
+
+		Display[] displays = _displayManager.getDisplays(
+			DisplayManager.DISPLAY_CATEGORY_PRESENTATION);
+
+		for (Display d : displays) {
+			if (d.getDisplayId() != 0 && !"HiddenDisplay".equals(d.getName())) {
+				return d;
+			}
+		}
+		return null;
+	}
+}