ListView.InsertionMark プロパティ
アセンブリ: System.Windows.Forms (system.windows.forms.dll 内)

挿入マークを表す ListViewInsertionMark オブジェクト。

ListView 挿入マーク機能を使用すると、ドラッグ アンド ドロップ操作で項目を新しい位置までドラッグしたときに、ドロップの予定位置を視覚的に示すことができます。この機能は、AutoArrange プロパティが true に設定され、ListView コントロールによって項目が自動的に並べ替えられない場合にのみ有効です。自動並べ替えが実行されないようにするには、Sorting プロパティを SortOrder.None に設定し、View プロパティを View.LargeIcon, View.SmallIcon またはView.Tile に設定する必要があります。さらに、挿入マーク機能は ListView グループ化機能と同時に使用できません。グループ化機能では、項目がグループのメンバシップに従って並べられるためです。
一般的に、Control.DragOver イベントまたは Control.MouseMove イベントのハンドラで ListViewInsertionMark クラスを使用して、項目がドラッグされているときに挿入マークの位置を更新します。これは、ドラッグしている項目を適切な位置に挿入するために Control.DragDrop イベントまたは Control.MouseUp イベントのハンドラでも使用されます。詳細については、「方法 : Windows フォーム ListView コントロールに挿入マークを表示する」を参照してください。
挿入マーク機能は、Windows XP および Windows Server 2003 でアプリケーションから Application.EnableVisualStyles メソッドを呼び出す場合にのみ使用できます。旧バージョンのオペレーティング システムでは、挿入マークに関するコードがすべて無効になり、挿入マークは表示されません。その結果、挿入マーク機能に依存するコードが正常に機能しない可能性があります。
この機能が使用できるかどうかを確認し、使用できない場合は代替機能を提供するコードを用意します。たとえば、挿入マークをサポートしないオペレーティング システムで実行する場合には、ドラッグ アンド ドロップによる項目の再配置を実装するコードをすべてバイパスできます。
挿入マーク機能は、オペレーティング システムのテーマ機能を提供しているライブラリと同じライブラリによって提供されます。このライブラリが使用できるかどうかを確認するには、FeatureSupport.IsPresent(Object) メソッド オーバーロードを呼び出し、OSFeature.Themes 値を渡します。

ListView の挿入マーク機能の使用方法を次のコード例に示します。この例では、標準のドラッグ イベントを使用して、ドラッグ アンド ドロップによる項目の並べ替えを実装しています。挿入マークの位置は、Control.DragOver イベントのハンドラで更新されます。このハンドラでは、マウス ポインタの位置を、最も近くにある項目の中心と比較し、その結果を使用して、挿入マークを項目の右に表示するか、左に表示するかを決定しています。
Imports System Imports System.Drawing Imports System.Windows.Forms Public Class ListViewInsertionMarkExample Inherits Form Private myListView As ListView Public Sub New() ' Initialize myListView. myListView = New ListView() myListView.Dock = DockStyle.Fill myListView.View = View.LargeIcon myListView.MultiSelect = False myListView.ListViewItemSorter = New ListViewIndexComparer() ' Initialize the insertion mark. myListView.InsertionMark.Color = Color.Green ' Add items to myListView. myListView.Items.Add("zero") myListView.Items.Add("one") myListView.Items.Add("two") myListView.Items.Add("three") myListView.Items.Add("four") myListView.Items.Add("five") ' Initialize the drag-and-drop operation when running ' under Windows XP or a later operating system. If OSFeature.Feature.IsPresent(OSFeature.Themes) myListView.AllowDrop = True AddHandler myListView.ItemDrag, AddressOf myListView_ItemDrag AddHandler myListView.DragEnter, AddressOf myListView_DragEnter AddHandler myListView.DragOver, AddressOf myListView_DragOver AddHandler myListView.DragLeave, AddressOf myListView_DragLeave AddHandler myListView.DragDrop, AddressOf myListView_DragDrop End If ' Initialize the form. Me.Text = "ListView Insertion Mark Example" Me.Controls.Add(myListView) End Sub 'New <STAThread()> _ Shared Sub Main() Application.EnableVisualStyles() Application.Run(New ListViewInsertionMarkExample()) End Sub 'Main ' Starts the drag-and-drop operation when an item is dragged. Private Sub myListView_ItemDrag(sender As Object, e As ItemDragEventArgs) myListView.DoDragDrop(e.Item, DragDropEffects.Move) End Sub 'myListView_ItemDrag ' Sets the target drop effect. Private Sub myListView_DragEnter(sender As Object, e As DragEventArgs) e.Effect = e.AllowedEffect End Sub 'myListView_DragEnter ' Moves the insertion mark as the item is dragged. Private Sub myListView_DragOver(sender As Object, e As DragEventArgs) ' Retrieve the client coordinates of the mouse pointer. Dim targetPoint As Point = myListView.PointToClient(New Point(e.X, e.Y)) ' Retrieve the index of the item closest to the mouse pointer. Dim targetIndex As Integer = _ myListView.InsertionMark.NearestIndex(targetPoint) ' Confirm that the mouse pointer is not over the dragged item. If targetIndex > -1 Then ' Determine whether the mouse pointer is to the left or ' the right of the midpoint of the closest item and set ' the InsertionMark.AppearsAfterItem property accordingly. Dim itemBounds As Rectangle = myListView.GetItemRect(targetIndex) If targetPoint.X > itemBounds.Left + (itemBounds.Width / 2) Then myListView.InsertionMark.AppearsAfterItem = True Else myListView.InsertionMark.AppearsAfterItem = False End If End If ' Set the location of the insertion mark. If the mouse is ' over the dragged item, the targetIndex value is -1 and ' the insertion mark disappears. myListView.InsertionMark.Index = targetIndex End Sub 'myListView_DragOver ' Removes the insertion mark when the mouse leaves the control. Private Sub myListView_DragLeave(sender As Object, e As EventArgs) myListView.InsertionMark.Index = -1 End Sub 'myListView_DragLeave ' Moves the item to the location of the insertion mark. Private Sub myListView_DragDrop(sender As Object, e As DragEventArgs) ' Retrieve the index of the insertion mark; Dim targetIndex As Integer = myListView.InsertionMark.Index ' If the insertion mark is not visible, exit the method. If targetIndex = -1 Then Return End If ' If the insertion mark is to the right of the item with ' the corresponding index, increment the target index. If myListView.InsertionMark.AppearsAfterItem Then targetIndex += 1 End If ' Retrieve the dragged item. Dim draggedItem As ListViewItem = _ CType(e.Data.GetData(GetType(ListViewItem)), ListViewItem) ' Insert a copy of the dragged item at the target index. ' A copy must be inserted before the original item is removed ' to preserve item index values. myListView.Items.Insert(targetIndex, _ CType(draggedItem.Clone(), ListViewItem)) ' Remove the original copy of the dragged item. myListView.Items.Remove(draggedItem) End Sub 'myListView_DragDrop ' Sorts ListViewItem objects by index. Private Class ListViewIndexComparer Implements System.Collections.IComparer Public Function Compare(x As Object, y As Object) As Integer _ Implements System.Collections.IComparer.Compare Return CType(x, ListViewItem).Index - CType(y, ListViewItem).Index End Function 'Compare End Class 'ListViewIndexComparer End Class 'ListViewInsertionMarkExample
using System; using System.Drawing; using System.Windows.Forms; public class ListViewInsertionMarkExample : Form { private ListView myListView; public ListViewInsertionMarkExample() { // Initialize myListView. myListView = new ListView(); myListView.Dock = DockStyle.Fill; myListView.View = View.LargeIcon; myListView.MultiSelect = false; myListView.ListViewItemSorter = new ListViewIndexComparer(); // Initialize the insertion mark. myListView.InsertionMark.Color = Color.Green; // Add items to myListView. myListView.Items.Add("zero"); myListView.Items.Add("one"); myListView.Items.Add("two"); myListView.Items.Add("three"); myListView.Items.Add("four"); myListView.Items.Add("five"); // Initialize the drag-and-drop operation when running // under Windows XP or a later operating system. if (OSFeature.Feature.IsPresent(OSFeature.Themes)) { myListView.AllowDrop = true; myListView.ItemDrag += new ItemDragEventHandler(myListView_ItemDrag); myListView.DragEnter += new DragEventHandler(myListView_DragEnter); myListView.DragOver += new DragEventHandler(myListView_DragOver); myListView.DragLeave += new EventHandler(myListView_DragLeave); myListView.DragDrop += new DragEventHandler(myListView_DragDrop); } // Initialize the form. this.Text = "ListView Insertion Mark Example"; this.Controls.Add(myListView); } [STAThread] static void Main() { Application.EnableVisualStyles(); Application.Run(new ListViewInsertionMarkExample()); } // Starts the drag-and-drop operation when an item is dragged. private void myListView_ItemDrag(object sender, ItemDragEventArgs e) { myListView.DoDragDrop(e.Item, DragDropEffects.Move); } // Sets the target drop effect. private void myListView_DragEnter(object sender, DragEventArgs e) { e.Effect = e.AllowedEffect; } // Moves the insertion mark as the item is dragged. private void myListView_DragOver(object sender, DragEventArgs e) { // Retrieve the client coordinates of the mouse pointer. Point targetPoint = myListView.PointToClient(new Point(e.X, e.Y)); // Retrieve the index of the item closest to the mouse pointer. int targetIndex = myListView.InsertionMark.NearestIndex(targetPoint); // Confirm that the mouse pointer is not over the dragged item. if (targetIndex > -1) { // Determine whether the mouse pointer is to the left or // the right of the midpoint of the closest item and set // the InsertionMark.AppearsAfterItem property accordingly. Rectangle itemBounds = myListView.GetItemRect(targetIndex); if ( targetPoint.X > itemBounds.Left + (itemBounds.Width / 2) ) { myListView.InsertionMark.AppearsAfterItem = true; } else { myListView.InsertionMark.AppearsAfterItem = false; } } // Set the location of the insertion mark. If the mouse is // over the dragged item, the targetIndex value is -1 and // the insertion mark disappears. myListView.InsertionMark.Index = targetIndex; } // Removes the insertion mark when the mouse leaves the control. private void myListView_DragLeave(object sender, EventArgs e) { myListView.InsertionMark.Index = -1; } // Moves the item to the location of the insertion mark. private void myListView_DragDrop(object sender, DragEventArgs e) { // Retrieve the index of the insertion mark; int targetIndex = myListView.InsertionMark.Index; // If the insertion mark is not visible, exit the method. if (targetIndex == -1) { return; } // If the insertion mark is to the right of the item with // the corresponding index, increment the target index. if (myListView.InsertionMark.AppearsAfterItem) { targetIndex++; } // Retrieve the dragged item. ListViewItem draggedItem = (ListViewItem)e.Data.GetData(typeof(ListViewItem)); // Insert a copy of the dragged item at the target index. // A copy must be inserted before the original item is removed // to preserve item index values. myListView.Items.Insert( targetIndex, (ListViewItem)draggedItem.Clone()); // Remove the original copy of the dragged item. myListView.Items.Remove(draggedItem); } // Sorts ListViewItem objects by index. private class ListViewIndexComparer : System.Collections.IComparer { public int Compare(object x, object y) { return ((ListViewItem)x).Index - ((ListViewItem)y).Index; } } }
#using <System.dll> #using <System.Windows.Forms.dll> #using <System.Drawing.dll> using namespace System; using namespace System::Drawing; using namespace System::Windows::Forms; public ref class ListViewInsertionMarkExample: public Form { private: ListView^ myListView; public: ListViewInsertionMarkExample() { // Initialize myListView. myListView = gcnew ListView; myListView->Dock = DockStyle::Fill; myListView->View = View::LargeIcon; myListView->MultiSelect = false; myListView->ListViewItemSorter = gcnew ListViewIndexComparer; // Initialize the insertion mark. myListView->InsertionMark->Color = Color::Green; // Add items to myListView. myListView->Items->Add( "zero" ); myListView->Items->Add( "one" ); myListView->Items->Add( "two" ); myListView->Items->Add( "three" ); myListView->Items->Add( "four" ); myListView->Items->Add( "five" ); // Initialize the drag-and-drop operation when running // under Windows XP or a later operating system. if ( System::Environment::OSVersion->Version->Major > 5 || (System::Environment::OSVersion->Version->Major == 5 && System::Environment::OSVersion->Version->Minor >= 1) ) { myListView->AllowDrop = true; myListView->ItemDrag += gcnew ItemDragEventHandler( this, &ListViewInsertionMarkExample::myListView_ItemDrag ); myListView->DragEnter += gcnew DragEventHandler( this, &ListViewInsertionMarkExample::myListView_DragEnter ); myListView->DragOver += gcnew DragEventHandler( this, &ListViewInsertionMarkExample::myListView_DragOver ); myListView->DragLeave += gcnew EventHandler( this, &ListViewInsertionMarkExample::myListView_DragLeave ); myListView->DragDrop += gcnew DragEventHandler( this, &ListViewInsertionMarkExample::myListView_DragDrop ); } // Initialize the form. this->Text = "ListView Insertion Mark Example"; this->Controls->Add( myListView ); } private: // Starts the drag-and-drop operation when an item is dragged. void myListView_ItemDrag( Object^ /*sender*/, ItemDragEventArgs^ e ) { myListView->DoDragDrop( e->Item, DragDropEffects::Move ); } // Sets the target drop effect. void myListView_DragEnter( Object^ /*sender*/, DragEventArgs^ e ) { e->Effect = e->AllowedEffect; } // Moves the insertion mark as the item is dragged. void myListView_DragOver( Object^ /*sender*/, DragEventArgs^ e ) { // Retrieve the client coordinates of the mouse pointer. Point targetPoint = myListView->PointToClient( Point(e->X,e->Y) ); // Retrieve the index of the item closest to the mouse pointer. int targetIndex = myListView->InsertionMark->NearestIndex( targetPoint ); // Confirm that the mouse pointer is not over the dragged item. if ( targetIndex > -1 ) { // Determine whether the mouse pointer is to the left or // the right of the midpoint of the closest item and set // the InsertionMark.AppearsAfterItem property accordingly. Rectangle itemBounds = myListView->GetItemRect( targetIndex ); if ( targetPoint.X > itemBounds.Left + (itemBounds.Width / 2) ) { myListView->InsertionMark->AppearsAfterItem = true; } else { myListView->InsertionMark->AppearsAfterItem = false; } } // Set the location of the insertion mark. If the mouse is // over the dragged item, the targetIndex value is -1 and // the insertion mark disappears. myListView->InsertionMark->Index = targetIndex; } // Removes the insertion mark when the mouse leaves the control. void myListView_DragLeave( Object^ /*sender*/, EventArgs^ /*e*/ ) { myListView->InsertionMark->Index = -1; } // Moves the item to the location of the insertion mark. void myListView_DragDrop( Object^ /*sender*/, DragEventArgs^ e ) { // Retrieve the index of the insertion mark; int targetIndex = myListView->InsertionMark->Index; // If the insertion mark is not visible, exit the method. if ( targetIndex == -1 ) { return; } // If the insertion mark is to the right of the item with // the corresponding index, increment the target index. if ( myListView->InsertionMark->AppearsAfterItem ) { targetIndex++; } // Retrieve the dragged item. ListViewItem^ draggedItem = dynamic_cast<ListViewItem^>(e->Data->GetData( ListViewItem::typeid )); // Insert a copy of the dragged item at the target index. // A copy must be inserted before the original item is removed // to preserve item index values. myListView->Items->Insert( targetIndex, dynamic_cast<ListViewItem^>(draggedItem->Clone()) ); // Remove the original copy of the dragged item. myListView->Items->Remove( draggedItem ); } // Sorts ListViewItem objects by index. ref class ListViewIndexComparer: public System::Collections::IComparer { public: virtual int Compare( Object^ x, Object^ y ) { return (dynamic_cast<ListViewItem^>(x))->Index - (dynamic_cast<ListViewItem^>(y))->Index; } }; }; [STAThread] int main() { Application::EnableVisualStyles(); Application::Run( gcnew ListViewInsertionMarkExample ); }
import System.*; import System.Drawing.*; import System.Windows.Forms.*; public class ListViewInsertionMarkExample extends Form { private ListView myListView; public ListViewInsertionMarkExample() { // Initialize myListView. myListView = new ListView(); myListView.set_Dock(DockStyle.Fill); myListView.set_View(View.LargeIcon); myListView.set_MultiSelect(false); myListView.set_ListViewItemSorter(new ListViewIndexComparer()); // Initialize the insertion mark. myListView.get_InsertionMark().set_Color(Color.get_Green()); // Add items to myListView. myListView.get_Items().Add("zero"); myListView.get_Items().Add("one"); myListView.get_Items().Add("two"); myListView.get_Items().Add("three"); myListView.get_Items().Add("four"); myListView.get_Items().Add("five"); // Initialize the drag-and-drop operation when running // under Windows XP or a later operating system. if (System.Environment.get_OSVersion().get_Version().get_Major() > 5 || (System.Environment.get_OSVersion().get_Version().get_Major() == 5 && System.Environment.get_OSVersion().get_Version(). get_Minor() >= 1)) { myListView.set_AllowDrop(true); myListView.add_ItemDrag(new ItemDragEventHandler( myListView_ItemDrag)); myListView.add_DragEnter(new DragEventHandler( myListView_DragEnter)); myListView.add_DragOver(new DragEventHandler(myListView_DragOver)); myListView.add_DragLeave(new EventHandler(myListView_DragLeave)); myListView.add_DragDrop(new DragEventHandler(myListView_DragDrop)); } // Initialize the form. this.set_Text("ListView Insertion Mark Example"); this.get_Controls().Add(myListView); } //ListViewInsertionMarkExample /** @attribute STAThread() */ public static void main(String[] args) { Application.Run(new ListViewInsertionMarkExample()); } //main // Starts the drag-and-drop operation when an item is dragged. private void myListView_ItemDrag(Object sender, ItemDragEventArgs e) { myListView.DoDragDrop(e.get_Item(), DragDropEffects.Move); } //myListView_ItemDrag // Sets the target drop effect. private void myListView_DragEnter(Object sender, DragEventArgs e) { e.set_Effect(e.get_AllowedEffect()); } //myListView_DragEnter // Moves the insertion mark as the item is dragged. private void myListView_DragOver(Object sender, DragEventArgs e) { // Retrieve the client coordinates of the mouse pointer. Point targetPoint = myListView.PointToClient( new Point(e.get_X(), e.get_Y())); // Retrieve the index of the item closest to the mouse pointer. int targetIndex = myListView.get_InsertionMark(). NearestIndex(targetPoint); // Confirm that the mouse pointer is not over the dragged item. if (targetIndex > -1) { // Determine whether the mouse pointer is to the left or // the right of the midpoint of the closest item and set // the InsertionMark.AppearsAfterItem property accordingly. Rectangle itemBounds = myListView.GetItemRect(targetIndex); if (targetPoint.get_X() > itemBounds.get_Left() + itemBounds.get_Width() / 2) { myListView.get_InsertionMark().set_AppearsAfterItem(true); } else { myListView.get_InsertionMark().set_AppearsAfterItem(false); } } // Set the location of the insertion mark. If the mouse is // over the dragged item, the targetIndex value is -1 and // the insertion mark disappears. myListView.get_InsertionMark().set_Index(targetIndex); } //myListView_DragOver // Removes the insertion mark when the mouse leaves the control. private void myListView_DragLeave(Object sender, EventArgs e) { myListView.get_InsertionMark().set_Index(-1); } //myListView_DragLeave // Moves the item to the location of the insertion mark. private void myListView_DragDrop(Object sender, DragEventArgs e) { // Retrieve the index of the insertion mark; int targetIndex = myListView.get_InsertionMark().get_Index(); // If the insertion mark is not visible, exit the method. if (targetIndex == -1) { return; } // If the insertion mark is to the right of the item with // the corresponding index, increment the target index. if (myListView.get_InsertionMark().get_AppearsAfterItem()) { targetIndex++; } // Retrieve the dragged item. ListViewItem draggedItem = (ListViewItem)(e.get_Data().GetData( ListViewItem.class.ToType())); // Insert a copy of the dragged item at the target index. // A copy must be inserted before the original item is removed // to preserve item index values. myListView.get_Items().Insert(targetIndex, (ListViewItem) draggedItem.Clone()); // Remove the original copy of the dragged item. myListView.get_Items().Remove(draggedItem); } //myListView_DragDrop // Sorts ListViewItem objects by index. private class ListViewIndexComparer implements System.Collections.IComparer { public int Compare(Object x, Object y) { return ((ListViewItem)x).get_Index() - ((ListViewItem)y).get_Index(); } //Compare } //ListViewIndexComparer } //ListViewInsertionMarkExample

Windows 98, Windows 2000 SP4, Windows CE, Windows Millennium Edition, Windows Mobile for Pocket PC, Windows Mobile for Smartphone, Windows Server 2003, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP SP2, Windows XP Starter Edition
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ListViewInsertionMark プロパティ
- ListView.InsertionMark プロパティのページへのリンク