Merge pull request #5426 from msupply-foundation/5383-android-12

5383 Android - Load Plugins after they've be registered properly

Author: jmbrunskill

client/packages/android/README.MD

@@ -12,22 +12,22 @@ The UI is not bundled within Capacitor, it is served by the server the client co
 Before building the Android app, the Rust server library that allows us to run the mSupply server on the mobile device needs to be built.
 This requires a couple of steps.
 
-- Install Android Studio
+- Install Android Studio (Ladybug at time of writing 15/11/24)
 - Install NDK (26.1.10909125 at the time of writing on the 8/4/24)
 
 ![omSupply Android NDK](./doc/omSupply_android_ndk.png)
 
-Currently, we support two Android architectures;
+Currently, we support only 1 Android architecture (64bit);
 
 | rust target             | android ABI |
-| ----------------------- | ----------- |
 | aarch64-linux-android   | arm64-v8a   |
-| armv7-linux-androideabi | armeabi-v7a |
+| ----------------------- | ----------- |
+
 
 To add the required build targets to Rust run:
 
 ```bash
-rustup target add aarch64-linux-android && rustup target add armv7-linux-androideabi
+rustup target add aarch64-linux-android
 ```
 
 Next we have to tell Rust where to find the Android NDK binaries required to link the server library.

client/packages/android/app/src/main/java/org/openmsupply/client/ExtendedWebViewClient.java

@@ -11,16 +11,24 @@
 
 import java.util.Arrays;
 import java.util.List;
+import java.util.ArrayList;
+
+
 
 public class ExtendedWebViewClient extends BridgeWebViewClient {
     Bridge bridge;
     String jsInject;
 
     public ExtendedWebViewClient(Bridge bridge) {
         super(bridge);
-
         this.bridge = bridge;
-        this.jsInject = this.generatePluginScript();
+    }
+
+    public void loadJsInject() {
+        if(this.jsInject == null) {
+            Logger.debug("Generating JS");
+            this.jsInject = this.generatePluginScript();
+        }
     }
 
     // Have to manually inject Capacitor JS, this typically happens in
@@ -31,26 +39,35 @@ public ExtendedWebViewClient(Bridge bridge) {
     public void onPageStarted(WebView webView, String url, Bitmap favicon) {
         if (url.startsWith("data:text")) return;
 
+        // Just incase the js hasn't been generated yet, generate it here.
+        this.loadJsInject();
+
         if(this.jsInject != null) {
+            Logger.debug("injecting JS");
             // .post to run on UI thread
             webView.post(() -> webView.evaluateJavascript(this.jsInject, null));
+        } else {
+            Logger.error("JS not generated, not injecting");
+            webView.post(() -> webView.evaluateJavascript("alert('Error unable to load javascript to inject. Please contact mSupply Support for assistance.')", null));
         }
     }
 
     String generatePluginScript() {
         // TODO make sure this is only injected for pages in native bundle
         // There is no way to get the full list of plugins from bridge, use 'debug' and
         // see what plugins to add
-        List<PluginHandle> pluginList = Arrays.asList(
-                bridge.getPlugin("NativeApi"),
-                bridge.getPlugin("Keyboard"),
-                bridge.getPlugin("WebView"),
-                bridge.getPlugin("BarcodeScanner"),
-                bridge.getPlugin("Preferences"),
-                bridge.getPlugin("KeepAwake"),
-                bridge.getPlugin("App"),
-                bridge.getPlugin("Printer")
-        );
+
+        // This function needs to run after plugins are registered, so can't be part of the constructor as order doesn't appear to be consistent.
+        List<String> pluginNames =  Arrays.asList("NativeApi","Keyboard", "WebView","BarcodeScanner","Preferences", "KeepAwake", "App", "Printer");
+        List<PluginHandle> pluginList = new ArrayList<>();
+        for (String pluginName : pluginNames) {
+            PluginHandle plugin = bridge.getPlugin(pluginName);
+            if (plugin == null) {
+                Logger.error("Couldn't find plugin : " + pluginName);
+                return null;
+            }
+            pluginList.add(plugin);
+        }
 
         try {
             // From Bridge.getJSInjector()

client/packages/android/app/src/main/java/org/openmsupply/client/NativeApi.java

@@ -64,11 +64,13 @@ public class NativeApi extends Plugin implements NsdManager.DiscoveryListener {
     boolean isResolvingServer;
     boolean shouldRestartDiscovery;
 
+    CertWebViewClient client;
+
     @Override
     public void load() {
         super.load();
 
-        CertWebViewClient client = new CertWebViewClient(this.getBridge(), this.getContext().getFilesDir(), this);
+        client = new CertWebViewClient(this.getBridge(), this.getContext().getFilesDir(), this);
         bridge.setWebViewClient(client);
 
         serversToResolve = new ArrayDeque<NsdServiceInfo>();
@@ -111,7 +113,19 @@ private void sleep(int delay) {
 
     @Override
     protected void handleOnStart() {
+        Logger.debug("NativeAPI.handleOnStart()");
         WebView webView = this.getBridge().getWebView();
+
+        // Normally javascript would be loaded by Capacitor by loading the generated javascript from WEBVIEW_SERVER_URL
+        // However we'd get an SSL issue with this approach, so we need to generate it ourselves and inject it later.
+
+        // NOTE: There have been various timing issues with this javascript injection loading
+        // We do the actual injection during onPageStarted in ExtendedWebViewClient
+        // We call it here as well as in ExtendedWebViewClient as this gives more time for it to be generated before the webview loads
+        // Potentially avoiding issues if it takes too long to generate.
+        client.loadJsInject();
+
+
         // this method (handleOnStart) is called when resuming and switching to the app
         // the webView url will be DEFAULT_URL only on the initial load
         // so this test is a quick check to see if we should be redirecting to the

client/packages/android/app/src/main/java/org/openmsupply/client/RemoteServer.java

@@ -1,5 +1,7 @@
 package org.openmsupply.client;
 
+import com.getcapacitor.Logger;
+
 public class RemoteServer {
     static {
         // This will load libremote_server_android, from app/src/main/jniLib/ directory
@@ -12,6 +14,7 @@ public RemoteServer() {
     }
 
     public void start(int port, String filesDir, String cacheDir, String androidId) {
+        Logger.info("Starting OMS Rust Server");
         startServer(port, filesDir, cacheDir, androidId);
     }