Updated zoom level

Changelog.md

@@ -3,6 +3,7 @@
 ## ElectronNET.Core
 
 - Updated dependencies
+- Updated `WebContents` zoom level APIs to use `double` instead of `int` (#956)
 - Improved migration checks to honor custom output paths and to detect `ProjectGuid` in publish profiles (#946)
 - Fixed single instance handling on macOS (#1040)
 - Fixed slow socket bridge startup by binding to an explicit loopback address (#1103)
@@ -11,6 +12,7 @@
 - Fixed cross-compilation behavior on same platform (#1098) @epsnm
 - Fixed resolution of unrelated target (#1099) @epsnm
 - Fixed false alarm for `ELECTRON001` on a root `package-lock.json` (#946)
+- Added `WebContents.OnZoomChanged` event (#956)
 - Added target framework customization (#1095) @epsnm
 - Added configurable Electron root directory for custom packaging layouts (#1106) @DYH1319
 - Added ability for `custom_main.js` to modify command line switches (#1029) @AeonSake

docs/API/WebContents.md

@@ -113,6 +113,31 @@ Prints window's web page as PDF with Chromium's preview printing custom settings
 
 Whether the PDF generation succeeded.
 
+#### 🧊 `Task<double> GetZoomFactorAsync()`
+Returns the current zoom factor. A factor of `1.0` means 100%.
+
+#### 🧊 `void SetZoomFactor(double factor)`
+Changes the zoom factor to the specified factor. The zoom factor is the zoom percent divided by 100, so 300% = `3.0`. The factor must be greater than `0.0`.
+
+**Parameters:**
+- `factor` - The zoom factor
+
+#### 🧊 `Task<double> GetZoomLevelAsync()`
+Returns the current zoom level.
+
+#### 🧊 `void SetZoomLevel(double level)`
+Changes the zoom level to the specified level. The original size is `0` and each increment above or below represents zooming 20% larger or smaller to default limits of 300% and 50% of the original size, respectively.
+
+**Parameters:**
+- `level` - The zoom level
+
+#### 🧊 `Task SetVisualZoomLevelLimitsAsync(double minimumLevel, double maximumLevel)`
+Sets the maximum and minimum pinch-to-zoom level.
+
+**Parameters:**
+- `minimumLevel` - The minimum pinch-to-zoom level
+- `maximumLevel` - The maximum pinch-to-zoom level
+
 ## Events
 
 #### ⚡ `InputEvent`
@@ -142,6 +167,9 @@ Emitted when the document in the top-level frame is loaded.
 #### ⚡ `OnWillRedirect`
 Emitted when a server side redirect occurs during navigation.
 
+#### ⚡ `OnZoomChanged`
+Emitted when the user changes the zoom level using the mouse wheel or the keyboard. The handler receives the `ZoomDirection` (`In` or `Out`).
+
 ## Usage Examples
 
 ### Page Loading
@@ -279,6 +307,30 @@ webContents.OnCrashed += (killed) =>
 };
 ```
 
+### Zoom Control
+
+```csharp
+// Set the zoom to 150%
+webContents.SetZoomFactor(1.5);
+
+var factor = await webContents.GetZoomFactorAsync();
+Console.WriteLine($"Current zoom: {factor * 100}%");
+
+// Zoom levels are relative: each step is 20% larger/smaller, 0 is the original size
+webContents.SetZoomLevel(2);
+
+// Restrict pinch-to-zoom
+await webContents.SetVisualZoomLevelLimitsAsync(1, 3);
+
+// React to zoom changes triggered by the user
+webContents.OnZoomChanged += (direction) =>
+{
+    Console.WriteLine($"User zoomed {direction}");
+};
+```
+
+> **Note:** The zoom factor is shared by all windows using the same session partition. Assign a unique `WebPreferences.Partition` per window if each window should keep its own zoom.
+
 ## Related APIs
 
 - [Electron.WindowManager](WindowManager.md) - Windows containing web contents

src/ElectronNET.API/API/Entities/ZoomDirection.cs

@@ -0,0 +1,18 @@
+namespace ElectronNET.API.Entities
+{
+    /// <summary>
+    /// The direction of a zoom change triggered by the user.
+    /// </summary>
+    public enum ZoomDirection
+    {
+        /// <summary>
+        /// The user zoomed in.
+        /// </summary>
+        In,
+
+        /// <summary>
+        /// The user zoomed out.
+        /// </summary>
+        Out
+    }
+}

src/ElectronNET.API/API/WebContents.cs

@@ -113,6 +113,15 @@ public class WebContents : ApiBase
         remove => RemoveEvent(value, Id);
     }
 
+    /// <summary>
+    /// Emitted when the user is requesting to change the zoom level using the mouse wheel or the keyboard.
+    /// </summary>
+    public event Action<ZoomDirection> OnZoomChanged
+    {
+        add => AddEvent(value, Id);
+        remove => RemoveEvent(value, Id);
+    }
+
     internal WebContents(int id)
     {
         Id = id;
@@ -337,14 +346,14 @@ public class WebContents : ApiBase
     /// Returns number - The current zoom level.
     /// </summary>
     /// <returns></returns>
-    public Task<int> GetZoomLevelAsync() => InvokeAsync<int>();
+    public Task<double> GetZoomLevelAsync() => InvokeAsync<double>();
 
     /// <summary>
     /// Changes the zoom level to the specified level.
     /// The original size is 0 and each increment above or below represents zooming 20% larger or smaller to default limits of 300% and 50% of original size, respectively.
     /// </summary>
     /// <param name="level"></param>
-    public void SetZoomLevel(int level)
+    public void SetZoomLevel(double level)
     {
         BridgeConnector.Socket.Emit("webContents-setZoomLevel", Id, level);
     }
@@ -354,7 +363,7 @@ public class WebContents : ApiBase
     /// </summary>
     /// <param name="minimumLevel"></param>
     /// <param name="maximumLevel"></param>
-    public Task SetVisualZoomLevelLimitsAsync(int minimumLevel, int maximumLevel)
+    public Task SetVisualZoomLevelLimitsAsync(double minimumLevel, double maximumLevel)
     {
         var tcs = new TaskCompletionSource();
 

src/ElectronNET.Host/api/webContents.js

@@ -111,6 +111,13 @@ module.exports = (socket) => {
             electronSocket.emit("webContents-domReady" + id);
         });
     });
+    socket.on("register-webContents-zoomChanged", (id) => {
+        const browserWindow = getWindowById(id);
+        browserWindow.webContents.removeAllListeners("zoom-changed");
+        browserWindow.webContents.on("zoom-changed", (_, zoomDirection) => {
+            electronSocket.emit("webContents-zoomChanged" + id, zoomDirection);
+        });
+    });
     socket.on("webContents-openDevTools", (id, options) => {
         if (options) {
             getWindowById(id).webContents.openDevTools(options);

src/ElectronNET.Host/api/webContents.ts

@@ -103,6 +103,15 @@ export = (socket: Socket) => {
     });
   });
 
+  socket.on("register-webContents-zoomChanged", (id) => {
+    const browserWindow = getWindowById(id);
+
+    browserWindow.webContents.removeAllListeners("zoom-changed");
+    browserWindow.webContents.on("zoom-changed", (_, zoomDirection) => {
+      electronSocket.emit("webContents-zoomChanged" + id, zoomDirection);
+    });
+  });
+
   socket.on("webContents-openDevTools", (id, options) => {
     if (options) {
       getWindowById(id).webContents.openDevTools(options);

src/ElectronNET.IntegrationTests/Tests/WebContentsTests.cs

@@ -108,13 +108,19 @@ namespace ElectronNET.IntegrationTests.Tests
                 await Task.Delay(500.ms());
 
                 var ok = await window.WebContents.GetZoomLevelAsync();
-                ok.Should().Be(0);
+                ok.Should().Be(0.0);
 
                 window.WebContents.SetZoomLevel(2);
                 await Task.Delay(500.ms());
 
                 ok = await window.WebContents.GetZoomLevelAsync();
-                ok.Should().Be(2);
+                ok.Should().Be(2.0);
+
+                window.WebContents.SetZoomLevel(0.5);
+                await Task.Delay(500.ms());
+
+                ok = await window.WebContents.GetZoomLevelAsync();
+                ok.Should().BeApproximately(0.5, 0.001);
             }
             finally
             {