支持添加删除服务器信息，以在服务器状态页显示CPU、内存等

lib/view/widget/card_dialog.dart

@@ -0,0 +1,25 @@
+import 'package:flutter/material.dart';
+
+class CardDialog extends StatelessWidget {
+  const CardDialog(
+      {Key? key, this.title, this.content, this.actions, this.padding})
+      : super(key: key);
+
+  final Widget? content;
+  final List<Widget>? actions;
+  final Widget? title;
+  final EdgeInsets? padding;
+
+  @override
+  Widget build(BuildContext context) {
+    return AlertDialog(
+      contentPadding: padding ?? const EdgeInsets.fromLTRB(24, 17, 24, 7),
+      shape: const RoundedRectangleBorder(
+        borderRadius: BorderRadius.all(Radius.circular(20.0)),
+      ),
+      title: title,
+      content: content,
+      actions: actions,
+    );
+  }
+}

lib/view/widget/circle_pie.dart

@@ -1,5 +1,3 @@
-import 'dart:math';
-// EXCLUDE_FROM_GALLERY_DOCS_END
 import 'package:charts_flutter/flutter.dart' as charts;
 import 'package:flutter/material.dart';
 
@@ -7,59 +5,28 @@ class DonutPieChart extends StatelessWidget {
   final List<charts.Series<dynamic, num>> seriesList;
   final bool animate;
 
-  const DonutPieChart(this.seriesList, {Key? key, this.animate = true}) : super(key: key);
-
-  factory DonutPieChart.withRandomData() {
-    return DonutPieChart(_createRandomData());
-  }
-
-  /// Create random data.
-  static List<charts.Series<IndexPercent, int>> _createRandomData() {
-    final random = Random();
-
-    final data = [
-      IndexPercent(0, random.nextInt(100)),
-      IndexPercent(1, random.nextInt(100)),
-      IndexPercent(2, random.nextInt(100)),
-      IndexPercent(3, random.nextInt(100)),
-    ];
-
-    return [
-      charts.Series<IndexPercent, int>(
-        id: 'Sales',
-        domainFn: (IndexPercent sales, _) => sales.id,
-        measureFn: (IndexPercent sales, _) => sales.percent,
-        data: data,
-      )
-    ];
-  }
-  // EXCLUDE_FROM_GALLERY_DOCS_END
+  const DonutPieChart(this.seriesList, {Key? key, this.animate = false})
+      : super(key: key);
 
   @override
   Widget build(BuildContext context) {
     return charts.PieChart(seriesList,
         animate: animate,
         layoutConfig: charts.LayoutConfig(
-          leftMarginSpec: charts.MarginSpec.fixedPixel(1), 
-          topMarginSpec: charts.MarginSpec.fixedPixel(1), 
-          rightMarginSpec: charts.MarginSpec.fixedPixel(1),
-          bottomMarginSpec: charts.MarginSpec.fixedPixel(17)
-        ),
-        // Configure the width of the pie slices to 60px. The remaining space in
-        // the chart will be left as a hole in the center.
+            leftMarginSpec: charts.MarginSpec.fixedPixel(1),
+            topMarginSpec: charts.MarginSpec.fixedPixel(1),
+            rightMarginSpec: charts.MarginSpec.fixedPixel(1),
+            bottomMarginSpec: charts.MarginSpec.fixedPixel(17)),
         defaultRenderer: charts.ArcRendererConfig<num>(
           arcWidth: 6,
-          minHoleWidthForCenterContent: 60,
           arcRatio: 0.2,
-        )
-      );
+        ));
   }
 }
 
-/// Sample linear data type.
 class IndexPercent {
   final int id;
   final int percent;
 
   IndexPercent(this.id, this.percent);
-}
+}