{"id":9026,"date":"2018-04-27T14:00:11","date_gmt":"2018-04-27T05:00:11","guid":{"rendered":"http:\/\/www.moonmile.net\/blog\/?p=9026"},"modified":"2018-05-08T22:13:34","modified_gmt":"2018-05-08T13:13:34","slug":"datagrid-%e3%81%ae-selecteditem-%e3%81%ab%e3%83%90%e3%82%a4%e3%83%b3%e3%83%89%e3%81%97%e3%81%a6%e3%81%84%e3%82%8b%e3%81%a8%e3%80%81itemssource-%e5%86%8d%e8%a8%ad%e5%ae%9a%e6%99%82%e3%81%ab%e8%90%bd","status":"publish","type":"post","link":"https:\/\/www.moonmile.net\/blog\/archives\/9026","title":{"rendered":"DataGrid \u306e SelectedItem \u306b\u30d0\u30a4\u30f3\u30c9\u3057\u3066\u3044\u308b\u3068\u3001ItemsSource \u518d\u8a2d\u5b9a\u6642\u306b\u843d\u3061\u308b"},"content":{"rendered":"

\u3061\u3087\u3063\u3068\u3070\u304b\u3057\u3001\u30cf\u30de\u3063\u305f\u306e\u3067\u30e1\u30e2\u66f8\u304d\u3092\u3057\u3066\u304a\u304f\u3002<\/p>\n

WPF\u306eDataGrid\u306b\u30c7\u30fc\u30bf\u30d0\u30a4\u30f3\u30c9\u3059\u308b<\/h2>\n

WPF\u3067\u30ea\u30b9\u30c8\u8868\u793a\u3092\u3059\u308b\u3068\u304d\u306b\u3001ListView\u304bDataGrid\u3092\u4f7f\u3046\u3068\u601d\u3046\u306e\u3060\u304c\u3001\u3053\u3053\u3067 MVVM \u3092\u4f7f\u3063\u3066 ItemsSource \u306b\u30d0\u30a4\u30f3\u30c9\u3059\u308b\u3002<\/p>\n

\r\n<Grid>\r\n    <Grid.RowDefinitions>\r\n        <RowDefinition Height=&quot;50&quot;\/>\r\n        <RowDefinition Height=&quot;*&quot;\/>\r\n    <\/Grid.RowDefinitions>\r\n    <DataGrid Grid.Row=&quot;1&quot; x:Name=&quot;lv&quot;\r\n                ItemsSource=&quot;{Binding Items}&quot;\r\n                SelectedItem=&quot;{Binding Item}&quot;\r\n                SelectedIndex=&quot;{Binding ItemIndex}&quot;      >\r\n    <\/DataGrid>\r\n<\/pre>\n
ViewModel \u3092\u4f5c\u3063\u3066<\/p>\n
\r\npublic class ViewModel : ObservableObject\r\n{\r\nprivate List<\u5546\u54c1> _items;\r\npublic List<\u5546\u54c1> Items\r\n{\r\n    get { return _items; }\r\n    set { SetProperty(ref _items, value, nameof(Items)); }\r\n}\r\n\r\nprivate \u5546\u54c1 _item;\r\npublic \u5546\u54c1 Item\r\n{\r\n    get { return _item; }\r\n    set { SetProperty(ref _item, value, nameof(Item)); }\r\n}\r\nprivate int _itemIndex;\r\npublic int ItemIndex \r\n{\r\n        get { return _itemIndex; }\r\n        set { SetProperty(ref _itemIndex, value, nameof(ItemIndex)); }\r\n    }\r\n}\r\n<\/pre>\n
\u30ed\u30fc\u30c9\u6642\u306b\u8868\u793a\u3055\u305b\u308b\u3002<\/p>\n
\r\nprivate void MainWindow_Loaded(object sender, RoutedEventArgs e)\r\n{\r\n    _vm = new ViewModel();\r\n    var ent = new Database1Entities();\r\n    _vm.Items = ent.\u5546\u54c1.ToList();\r\n    this.DataContext = _vm;\r\n}\r\nViewModel _vm;\r\n<\/pre>\n
\u5b9f\u884c\u3059\u308b\u3068\u3001\u3053\u3093\u306a\u611f\u3058\u3002<\/p>\n
<\/a><\/p>\n
\u884c\u3092\u9078\u629e\u3059\u308b\u3068\u30d0\u30a4\u30f3\u30c9\u3057\u3066\u3044\u308b SelectedItem \u306b\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\uff08\u3053\u3053\u3067\u306f\u5546\u54c1\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\uff09\u304c\u5165\u308b\u306e\u3067\u3001\u8a73\u7d30\u30c7\u30fc\u30bf\u3068\u304b\u3092\u5225\u753b\u9762\u3067\u8868\u793a\u3059\u308b\u306b\u306f\u4fbf\u5229\u3060\u3063\u305f\u308a\u3059\u308b\u3002
\nSelectedIndex \u3067\u3082\u3044\u3044\u3088\u3046\u306a\u6c17\u3082\u3059\u308b\u306e\u3060\u304c\u3001\u5b9f\u306f\u3001DataGrid \u306f\u30d8\u30c3\u30c0\u3092\u30af\u30ea\u30c3\u30af\u3059\u308b\u3068\u30bd\u30fc\u30c8\u3059\u308b\u6a5f\u80fd\u304c\u521d\u3081\u304b\u3089\u5165\u3063\u3066\u3044\u3066\u3001\u7d50\u69cb\u4fbf\u5229\u3002\u3067\u3082\u3063\u3066\u3001\u30bd\u30fc\u30c8\u3057\u305f\u3068\u304d\u306f\u30a4\u30f3\u30c7\u30c3\u30af\u30b9\u304c\u5909\u308f\u3063\u3066\u3057\u307e\u3046\u306e\u3067\u3001SelectedIndex \u3067\u306f\u56f0\u308b\u306e\u3067\u3001SelectedItem \u304b\u3089\u9078\u629e\u3057\u305f\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u3092\u62fe\u3046\u3068\u826f\u3044\u3068\u3044\u3046\u8a33\u3002\u6e21\u3057\u3066\u3044\u308b List<\u5546\u54c1> \u3068 DataGird \u81ea\u8eab\u304c\u6301\u3063\u3066\u3044\u308b Items \u306e\u4e2d\u8eab\u304c\u7570\u306a\u308b\uff08\u30bd\u30fc\u30c8\u3055\u308c\u3066\u3044\u308b\uff09\u306e\u3067\u305a\u308c\u304c\u3067\u3066\u304f\u308b\u3002<\/p>\n
\u30ea\u30b9\u30c8\u3092\u30ea\u30d5\u30ec\u30c3\u30b7\u30e5\u3059\u308b\u3068\u843d\u3061\u308b<\/h2>\n
\u3055\u3066\u3001\u666e\u6bb5\u306f DataGrid \u306e\u4e2d\u8eab\u306f\u5909\u308f\u3089\u306a\u3044\u306e\u3067\u66f4\u65b0\u3059\u308b\u3053\u3068\u306f\u306a\u3044\u306e\u3060\u304c\u3001\u306a\u3093\u3089\u304b\u306e\u7406\u7531\u3067\u30ea\u30b9\u30c8\u3092\u518d\u63cf\u753b\u3055\u305b\u305f\u3044\u3068\u3057\u3088\u3046\u3002\u3053\u306e\u3068\u304d\u306b\u3001ItemsSource \u306b\u30d0\u30a4\u30f3\u30c9\u3057\u3066\u3044\u308b ViewModel \u5074\u306e Items \u3092\u66f4\u65b0\u3059\u308c\u3070\u3088\u3044\u3068\u601d\u3063\u3066\u3001\u6b21\u306a\u611f\u3058\u306b\u3059\u308b\u3068\u3001<\/p>\n
\r\nprivate void clickInit(object sender, RoutedEventArgs e)\r\n{\r\n    var ent = new Database1Entities();\r\n    _vm.Items = ent.\u5546\u54c1.ToList();\r\n}\r\n<\/pre>\n
\uff5e\uff5e\uff5e
\nSystem.NullReferenceException \u304c\u767a\u751f\u3057\u307e\u3057\u305f
\nHResult=0x80004003
\nMessage=\u30aa\u30d6\u30b8\u30a7\u30af\u30c8\u53c2\u7167\u304c\u30aa\u30d6\u30b8\u30a7\u30af\u30c8 \u30a4\u30f3\u30b9\u30bf\u30f3\u30b9\u306b\u8a2d\u5b9a\u3055\u308c\u3066\u3044\u307e\u305b\u3093\u3002
\n\uff5e\uff5e\uff5e<\/p>\n
\u306a\u308b\u4f8b\u5916\u304c\u767a\u751f\u3057\u3066\u843d\u3061\u308b\u3002\u305d\u308c\u3082\u3001_vm.Items \u306b\u4ee3\u5165\u3057\u3088\u3046\u3068\u3057\u3066\u3044\u308b\u3068\u3053\u308d\u3067\u843d\u3061\u308b\u306e\u3067\u59cb\u672b\u304c\u8ca0\u3048\u306a\u3044\u3002
\n\u5b9f\u306f\u3001\u521d\u671f\u8868\u793a\u3092\u3057\u3066\u3044\u3066\u3001\u30ab\u30fc\u30bd\u30eb\u3092 DataGird \u306b\u3042\u3066\u306a\u3044\u72b6\u614b\uff08\u9078\u629e\u884c\u304c\u7121\u3044\u72b6\u614b\uff09\u306e\u5834\u5408\u306f\u843d\u3061\u306a\u304f\u3066\u3001\u4e00\u5ea6\u9078\u629e\u3057\u305f\u5f8c\u306b\u306f\u4f8b\u5916\u304c\u767a\u751f\u3057\u3066\u843d\u3061\u308b\u306e\u3067\u3042\u308b\u3002
\n\u304b\u306a\u308a\u4e0d\u601d\u8b70\u306a\u73fe\u8c61\u3067\u3042\u308b\u3002\u30cd\u30c3\u30c8\u3067\u3082\u3042\u3061\u3053\u3061\u56f0\u3063\u3066\u3044\u308b\u4eba\u304c\u3044\u308b\u3082\u306e\u3001\u3074\u3063\u3061\u308a\u3068\u3057\u305f\u89e3\u6c7a\u7b56\u306f\u7121\u3044\u3088\u3046\u306b\u898b\u3048\u308b\u3001\u304c\u3001<\/p>\n
\u5b9f\u306f\u3001\u3053\u306e\u3088\u3046\u306b Item \u306b null \u3092\u4ee3\u5165\u3059\u308b\u3068\u843d\u3061\u306a\u304f\u306a\u308b\u3002<\/p>\n
\r\nprivate void clickReload(object sender, RoutedEventArgs e)\r\n{\r\n    var ent = new Database1Entities();\r\n    _vm.Item = null;\t\/\/ \u2605\r\n    _vm.Items = ent.\u5546\u54c1.ToList();\r\n}\r\n<\/pre>\n
\u305d\u3046\u3001ViewModel \u3092\u898b\u308b\u3068\u308f\u304b\u308b\u306e\u3060\u304c\u3001DataGrid \u306e SelectedItem \u3078\u306e\u30d0\u30a4\u30f3\u30c9\u304c\u60aa\u3055\u3092\u3057\u3066\u3044\u308b\u3002Items \u306b\u65b0\u3057\u3044\u30ea\u30b9\u30c8\u3092\u8a2d\u5b9a\u3057\u3066\u3001ItemsSource \u30d7\u30ed\u30d1\u30c6\u30a3\u3092\u66f4\u65b0\u3057\u3066\u3057\u307e\u3046\u3068\u3001SelectedItem \u304c\u884c\u5148\u3092\u898b\u5931\u3046\uff08\uff1f\uff09\u3053\u3068\u306b\u306a\u3063\u3066 NULL\u4f8b\u5916\u304c\u767a\u751f\u3059\u308b\u3089\u3057\u3044\u3002\u3053\u306e\u305f\u3081\u3001\u5148\u306b SelectedItem \u306b null \u3092\u8a2d\u5b9a\u3057\u3066\u3084\u3063\u3066\u3001\u30ab\u30fc\u30bd\u30eb\u3092\u5916\u3057\u305f\u5f8c\u3067 ItemsSource \u306b\u65b0\u3057\u3044\u30ea\u30b9\u30c8\u3092\u8a2d\u5b9a\u3059\u308b\u3053\u3068\u306b\u306a\u308b\u3002<\/p>\n
\u304a\u307e\u3051<\/h2>\n
\u3058\u3083\u3042\u3001ObservableCollection \u3092\u4f7f\u3063\u3066\u3001\u4e00\u5ea6\u30af\u30ea\u30a2\u3057\u305f\u3042\u3068\u306b1\u3064\u305a\u3064\u8ffd\u52a0\u3057\u3051\u3070\u3044\u3044\u3058\u3083\u306a\u3044\u304b\u3001\u3068\u601d\u3046\u304b\u3082\u3057\u308c\u306a\u3044\u304c\u3001\u5b9f\u306f\u305d\u308c\u3067\u3082\u843d\u3061\u308b\u3002<\/p>\n
\r\nprivate void clickReload(object sender, RoutedEventArgs e)\r\n{\r\n    var ent = new Database1Entities();\r\n    _vm.Item = null;\t\/\/ \u2605\r\n    _vm.Items.Clear();\r\n    foreach (var it in ent.\u5546\u54c1) _vm.Items.Add(it);\r\n}\r\n<\/pre>\n
\u666e\u901a\u306e Items \u306e\u66f4\u65b0\u3068\u540c\u3058\u3088\u3046\u306b\u3001\u2605\u90e8\u5206\u306e null \u306e\u8a2d\u5b9a\u304c\u306a\u3044\u3068\u3001_vm.Items.Clear() \u884c\u3067\u4f8b\u5916\u304c\u767a\u751f\u3057\u3066\u843d\u3061\u3066\u3057\u307e\u3046\u3002\u3053\u308c\u3082\u3001SelectedItem \u304c\u793a\u3057\u5148\u3092\u898b\u5931\u3063\u3066\u3057\u307e\u3046\u305f\u3081\u3089\u3057\u3044\u3002<\/p>\n","protected":false},"excerpt":{"rendered":"
\u3061\u3087\u3063\u3068\u3070\u304b\u3057\u3001\u30cf\u30de\u3063\u305f\u306e\u3067\u30e1\u30e2\u66f8\u304d\u3092\u3057\u3066\u304a\u304f\u3002 WPF\u306eDataGrid\u306b\u30c7\u30fc\u30bf\u30d0\u30a4\u30f3\u30c9\u3059\u308b WPF\u3067\u30ea\u30b9\u30c8\u8868\u793a\u3092\u3059\u308b\u3068\u304d\u306b\u3001ListView\u304bDataGrid\u3092\u4f7f\u3046\u3068\u601d\u3046\u306e\u3060\u304c\u3001\u3053\u3053\u3067 MVVM \u3092\u4f7f\u3063\u3066 Items … \u7d9a\u304d\u3092\u8aad\u3080 →<\/span><\/a><\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[3,23,49],"tags":[],"class_list":["post-9026","post","type-post","status-publish","format-standard","hentry","category-dev","category-csharp","category-xaml"],"jetpack_featured_media_url":"","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/posts\/9026","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/comments?post=9026"}],"version-history":[{"count":2,"href":"https:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/posts\/9026\/revisions"}],"predecessor-version":[{"id":9033,"href":"https:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/posts\/9026\/revisions\/9033"}],"wp:attachment":[{"href":"https:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/media?parent=9026"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/categories?post=9026"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.moonmile.net\/blog\/wp-json\/wp\/v2\/tags?post=9026"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}