Fix bug with back button

app/build.gradle

@@ -9,8 +9,8 @@ android {
         applicationId "nl.privacydragon.bookwyrm"
         minSdk 23
         targetSdk 31
-        versionCode 4
+        versionCode 5
-        versionName "1.2.1"
+        versionName "1.2.2"
 
         testInstrumentationRunner "android.support.test.runner.AndroidJUnitRunner"
     }

app/release/output-metadata.json

@@ -11,8 +11,8 @@
       "type": "SINGLE",
       "filters": [],
       "attributes": [],
-      "versionCode": 4,
+      "versionCode": 5,
-      "versionName": "1.2.1",
+      "versionName": "1.2.2",
       "outputFile": "app-release.apk"
     }
   ],

app/src/main/java/nl/privacydragon/bookwyrm/HandlerActivity.java

@@ -8,6 +8,7 @@ import android.net.Uri;
 import android.support.v7.app.AppCompatActivity;
 import android.os.Bundle;
 import android.util.Base64;
+import android.view.KeyEvent;
 import android.webkit.WebResourceRequest;
 import android.webkit.WebView;
 import android.webkit.WebViewClient;
@@ -31,6 +32,7 @@ import javax.crypto.spec.GCMParameterSpec;
 
 public class HandlerActivity extends AppCompatActivity {
 
+    WebView myWebView;
     @SuppressLint("SetJavaScriptEnabled")
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -41,7 +43,7 @@ public class HandlerActivity extends AppCompatActivity {
         String appLinkAction = appLinkIntent.getAction();
         Uri appLinkData = appLinkIntent.getData();
         // End of auto-generated stuff
-        WebView myWebView = (WebView) findViewById(R.id.webview);
+        myWebView = (WebView) findViewById(R.id.webview);
         myWebView.getSettings().setJavaScriptEnabled(true);
         //The user credentials are stored in the shared preferences, so first they have to be read from there.
         String defaultValue = "none";
@@ -149,6 +151,17 @@ public class HandlerActivity extends AppCompatActivity {
         //Here, load the login page of the server. That actually does all that is needed.
         myWebView.loadUrl(toGoServer);
     }
+    @Override
+    public boolean onKeyDown(int keyCode, KeyEvent event) {
+        // Check if the key event was the Back button and if there's history
+        if ((keyCode == KeyEvent.KEYCODE_BACK) && myWebView.canGoBack()) {
+            myWebView.goBack();
+            return true;
+        }
+        // If it wasn't the Back key or there's no web page history, bubble up to the default
+        // system behavior (probably exit the activity)
+        return super.onKeyDown(keyCode, event);
+    }
     //Here is code to make sure that links of the bookwyrm server are handled withing the webview client, instead of having it open in the default browser.
     //Yes, I used the web for this too.
     private class MyWebViewClient extends WebViewClient {

app/src/main/java/nl/privacydragon/bookwyrm/StartActivity.java

@@ -7,6 +7,7 @@ import android.content.SharedPreferences;
 import android.support.v7.app.AppCompatActivity;
 import android.os.Bundle;
 import android.util.Base64;
+import android.view.KeyEvent;
 import android.webkit.WebResourceRequest;
 import android.webkit.WebView;
 import android.webkit.WebViewClient;
@@ -29,13 +30,13 @@ import javax.crypto.NoSuchPaddingException;
 import javax.crypto.spec.GCMParameterSpec;
 
 public class StartActivity extends AppCompatActivity {
-
+    WebView myWebView;
     @SuppressLint("SetJavaScriptEnabled")
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_start);
-        WebView myWebView = (WebView) findViewById(R.id.webview);
+        myWebView = (WebView) findViewById(R.id.webview);
         myWebView.getSettings().setJavaScriptEnabled(true);
         //The user credentials are stored in the shared preferences, so first they have to be read from there.
         String defaultValue = "none";
@@ -118,6 +119,17 @@ public class StartActivity extends AppCompatActivity {
         //Here, load the login page of the server. That actually does all that is needed.
         myWebView.loadUrl("https://" + server + "/login");
     }
+    @Override
+    public boolean onKeyDown(int keyCode, KeyEvent event) {
+        // Check if the key event was the Back button and if there's history
+        if ((keyCode == KeyEvent.KEYCODE_BACK) && myWebView.canGoBack()) {
+            myWebView.goBack();
+            return true;
+        }
+        // If it wasn't the Back key or there's no web page history, bubble up to the default
+        // system behavior (probably exit the activity)
+        return super.onKeyDown(keyCode, event);
+    }
     //Here is code to make sure that links of the bookwyrm server are handled withing the webview client, instead of having it open in the default browser.
     //Yes, I used the web for this too.
     private class MyWebViewClient extends WebViewClient {