1 files changed, 62 insertions, 0 deletions
diff --git a/srcs/juloo.keyboard2/FoldStateTracker.java b/srcs/juloo.keyboard2/FoldStateTracker.java
new file mode 100644
index 0000000..60933c9
--- /dev/null
+++ b/srcs/juloo.keyboard2/FoldStateTracker.java
@@ -0,0 +1,62 @@
+package juloo.keyboard2;
+
+import android.content.Context;
+import android.content.pm.PackageManager;
+import androidx.window.java.layout.WindowInfoTrackerCallbackAdapter;
+import androidx.window.layout.DisplayFeature;
+import androidx.window.layout.FoldingFeature;
+import androidx.window.layout.WindowInfoTracker;
+import androidx.window.layout.WindowLayoutInfo;
+
+import androidx.core.util.Consumer;
+
+
+public class FoldStateTracker {
+    private final Consumer<WindowLayoutInfo> _innerListener;
+    private final WindowInfoTrackerCallbackAdapter _windowInfoTracker;
+    private FoldingFeature _foldingFeature = null;
+    private Runnable _changedCallback = null;
+    public FoldStateTracker(Context context) {
+        _windowInfoTracker =
+                new WindowInfoTrackerCallbackAdapter(WindowInfoTracker.getOrCreate(context));
+        _innerListener = new LayoutStateChangeCallback();
+        _windowInfoTracker.addWindowLayoutInfoListener(context, Runnable::run, _innerListener);
+    }
+
+    public static boolean isFoldableDevice(Context context) {
+        return context.getPackageManager().hasSystemFeature(PackageManager.FEATURE_SENSOR_HINGE_ANGLE);
+    }
+
+    public boolean isUnfolded() {
+        // FoldableFeature is only present when the device is unfolded. Otherwise, it's removed.
+        // A weird decision from Google, but that's how it works:
+        // https://cs.android.com/androidx/platform/frameworks/support/+/androidx-main:window/window/src/main/java/androidx/window/layout/adapter/sidecar/SidecarAdapter.kt;l=187?q=SidecarAdapter
+
+        return _foldingFeature != null;
+    }
+
+    public void close() {
+        _windowInfoTracker.removeWindowLayoutInfoListener(_innerListener);
+    }
+
+    public void setChangedCallback(Runnable _changedCallback) {
+        this._changedCallback = _changedCallback;
+    }
+
+    class LayoutStateChangeCallback implements Consumer<WindowLayoutInfo> {
+        @Override
+        public void accept(WindowLayoutInfo newLayoutInfo) {
+            FoldingFeature old = _foldingFeature;
+            _foldingFeature = null;
+            for (DisplayFeature feature: newLayoutInfo.getDisplayFeatures()) {
+                if (feature instanceof FoldingFeature) {
+                    _foldingFeature = (FoldingFeature) feature;
+                }
+            }
+
+            if (old != _foldingFeature && _changedCallback != null) {
+                _changedCallback.run();
+            }
+        }
+    }
+}