Android: add inset spacers (experimental)

src/Logic/Web/AndroidPolyfill.ts

@@ -94,6 +94,37 @@ export class AndroidPolyfill {
         return token
     }
 
+    /**
+     * Gets how much padding we should add on top and at the bottom; in pixels
+     */
+    private static insets: { top: Store<number>, bottom: Store<number> } = undefined
+
+    public static getInsetSizes(): Readonly<{ top: Store<number>, bottom: Store<number> }> {
+        if (AndroidPolyfill.insets) {
+            return AndroidPolyfill.insets
+        }
+        const insets = {
+            top: new UIEventSource(0),
+            bottom: new UIEventSource(0),
+        }
+        AndroidPolyfill.insets = insets
+
+        console.log("Web: requesting inset sizes")
+        DatabridgePluginSingleton.request<{ top: number, bottom: number }>({
+            key: "insets",
+        }).then((result) => {
+            let v = result.value
+            if(typeof v === "string"){
+                v = JSON.parse(v)
+            }
+            console.log("Got inset sizes:", result)
+            insets.bottom.set(v.bottom)
+            insets.top.set(v.top)
+        })
+
+        return insets
+    }
+
     public static onBackButton(
         callback: () => boolean,
         options: {