[macos] Implement setProgressBar method #40

Author: lijy91

example/lib/pages/home.dart

@@ -38,6 +38,7 @@ class _HomePageState extends State<HomePage> with WindowListener {
   bool _isClosable = true;
   bool _isAlwaysOnTop = false;
   bool _isSkipTaskbar = false;
+  double _progress = 0;
   bool _hasShadow = true;
   double _opacity = 1;
 
@@ -433,6 +434,19 @@ class _HomePageState extends State<HomePage> with WindowListener {
                 windowManager.show();
               },
             ),
+            PreferenceListItem(
+              title: Text('setProgressBar'),
+              onTap: () async {
+                for (var i = 0; i <= 100; i++) {
+                  setState(() {
+                    _progress = i / 100;
+                  });
+                  print(_progress);
+                  await windowManager.setProgressBar(_progress);
+                  await Future.delayed(Duration(milliseconds: 100));
+                }
+              },
+            ),
             PreferenceListSwitchItem(
               title: Text('hasShadow / setHasShadow'),
               onTap: () async {

lib/src/window_manager.dart

@@ -336,6 +336,14 @@ class WindowManager {
     await _channel.invokeMethod('setSkipTaskbar', arguments);
   }
 
+  /// Sets progress value in progress bar. Valid range is [0, 1.0].
+  Future<void> setProgressBar(double progress) async {
+    final Map<String, dynamic> arguments = {
+      'progress': progress,
+    };
+    await _channel.invokeMethod('setProgressBar', arguments);
+  }
+
   /// Returns bool - Whether the window has a shadow.
   Future<bool> hasShadow() async {
     return await _channel.invokeMethod('hasShadow');

macos/Classes/WindowManager.swift

@@ -338,6 +338,43 @@ public class WindowManager: NSObject, NSWindowDelegate {
         NSApplication.shared.setActivationPolicy(isSkipTaskbar ? .accessory : .regular)
     }
 
+    public func setProgressBar(_ args: [String: Any]) {
+        let progress: CGFloat = CGFloat(truncating: args["progress"] as! NSNumber)
+        
+        let dockTile: NSDockTile = NSApp.dockTile;
+    
+        let firstTime = dockTile.contentView == nil || dockTile.contentView?.subviews.count == 0
+        
+        if (firstTime) {
+            let imageView: NSImageView = NSImageView.init()
+            imageView.image = NSApp.applicationIconImage
+            dockTile.contentView = imageView
+            
+            let frame: NSRect = NSMakeRect(0.0, 0.0, dockTile.size.width, 15.0)
+            let progressIndicator: NSProgressIndicator = NSProgressIndicator.init(frame: frame)
+            progressIndicator.style = .bar
+            progressIndicator.isIndeterminate = false
+            progressIndicator.isBezeled = true
+            progressIndicator.minValue = 0
+            progressIndicator.maxValue = 1
+            progressIndicator.isHidden = false
+            dockTile.contentView?.addSubview(progressIndicator)
+        }
+        
+        let progressIndicator: NSProgressIndicator = dockTile.contentView!.subviews.last as! NSProgressIndicator
+        if (progress < 0) {
+            progressIndicator.isHidden = true
+        } else if (progress > 1) {
+            progressIndicator.isHidden = false
+            progressIndicator.isIndeterminate = true
+            progressIndicator.doubleValue = 1
+        } else {
+            progressIndicator.isHidden = false
+            progressIndicator.doubleValue = progress
+        }
+        dockTile.display()
+    }
+    
     public func hasShadow() -> Bool {
         return mainWindow.hasShadow
     }

macos/Classes/WindowManagerPlugin.swift

@@ -180,6 +180,10 @@ public class WindowManagerPlugin: NSObject, FlutterPlugin {
             windowManager.setSkipTaskbar(args)
             result(true)
             break
+        case "setProgressBar":
+            windowManager.setProgressBar(args)
+            result(true)
+            break
         case "hasShadow":
             result(windowManager.hasShadow())
             break