Merge bitcoin-core/gui#18: Add peertablesortproxy module

5a4a15d2b4456272fd8aa080195f40a09576ae01 qt, refactor: Drop no longer used PeerTableModel::getRowByNodeId func (Hennadii Stepanov)
9a9f180df0d51396fee2468681df6dd935b0248e qt, refactor: Drop no longer used PeerTableModel::sort function (Hennadii Stepanov)
778a64af209e4fa692a3aca8376ba1bd5e1af881 qt: Use PeerTableSortProxy for sorting peer table (Hennadii Stepanov)
df2d165ba9e0acc53f36a326f68f57ad9c297872 qt: Add peertablesortproxy module (Hennadii Stepanov)

Pull request description:

  The "Peers" table in the "Node" window does not hold multiple selection after sorting.

  This PR introduces a `QSortFilterProxyModel` subclass, that is a standard Qt [practice](https://doc.qt.io/qt-5/model-view-programming.html#custom-sorting-models) for such cases.

  Now the sorting code is encapsulated into the dedicated Qt class, and we do not need to maintain it.

  Fixes #283 (additionally).

  ---

  On **master** (7ae86b3c6845873ca96650fc69beb4ae5285c801):
  - rows are sorted by "Ping", and a selection is made
  ![Screenshot from 2020-11-28 22-53-11](https://user-images.githubusercontent.com/32963518/100525900-96eaed00-31cc-11eb-86e7-72ede3b8b33c.png)

  - rows are sorted by "NodeId", and the previous selection is _lost_
  ![Screenshot from 2020-11-28 22-53-21](https://user-images.githubusercontent.com/32963518/100525904-9c483780-31cc-11eb-957c-06f53d7d31ab.png)

  With **this PR**:
  - rows are sorted by "Ping", and a selection is made
  ![Screenshot from 2020-11-28 22-39-41](https://user-images.githubusercontent.com/32963518/100525776-06aca800-31cc-11eb-8c4e-9c6566fe80fe.png)

  - rows are sorted by "NodeId", and the row are still selected
  ![Screenshot from 2020-11-28 22-39-53](https://user-images.githubusercontent.com/32963518/100525791-2348e000-31cc-11eb-8b78-716a5551d7ec.png)

ACKs for top commit:
  jarolrod:
    re-ACK 5a4a15d2b4456272fd8aa080195f40a09576ae01, tested on macOS 11.2 Qt 5.15.2 after rebase
  promag:
    Tested ACK 5a4a15d2b4456272fd8aa080195f40a09576ae01.

Tree-SHA512: f81c1385892fbf1a46ffb98b42094ca1cc97da52114bbbc94fedb553899b1f18c26a349e186bba6e27922a89426bd61e8bc88b1f7832512dbe211b5f834e076e

1 files changed, 6 insertions, 69 deletions

diff --git a/src/qt/rpcconsole.cpp b/src/qt/rpcconsole.cpp
index 85412ca75b..006f60e7a1 100644
--- a/src/qt/rpcconsole.cpp
+++ b/src/qt/rpcconsole.cpp
@@ -9,13 +9,14 @@
 #include <qt/rpcconsole.h>
 #include <qt/forms/ui_debugwindow.h>
 
+#include <chainparams.h>
+#include <interfaces/node.h>
+#include <netbase.h>
 #include <qt/bantablemodel.h>
 #include <qt/clientmodel.h>
+#include <qt/peertablesortproxy.h>
 #include <qt/platformstyle.h>
 #include <qt/walletmodel.h>
-#include <chainparams.h>
-#include <interfaces/node.h>
-#include <netbase.h>
 #include <rpc/client.h>
 #include <rpc/server.h>
 #include <util/strencodings.h>
@@ -606,7 +607,7 @@ void RPCConsole::setClientModel(ClientModel *model, int bestblock_height, int64_
         connect(model, &ClientModel::mempoolSizeChanged, this, &RPCConsole::setMempoolSize);
 
         // set up peer table
-        ui->peerWidget->setModel(model->getPeerTableModel());
+        ui->peerWidget->setModel(model->peerTableSortProxy());
         ui->peerWidget->verticalHeader()->hide();
         ui->peerWidget->setSelectionBehavior(QAbstractItemView::SelectRows);
         ui->peerWidget->setSelectionMode(QAbstractItemView::ExtendedSelection);
@@ -627,10 +628,7 @@ void RPCConsole::setClientModel(ClientModel *model, int bestblock_height, int64_
 
         // peer table signal handling - update peer details when selecting new node
         connect(ui->peerWidget->selectionModel(), &QItemSelectionModel::selectionChanged, this, &RPCConsole::updateDetailWidget);
-        // peer table signal handling - update peer details when new nodes are added to the model
-        connect(model->getPeerTableModel(), &PeerTableModel::layoutChanged, this, &RPCConsole::peerLayoutChanged);
-        // peer table signal handling - cache selected node ids
-        connect(model->getPeerTableModel(), &PeerTableModel::layoutAboutToBeChanged, this, &RPCConsole::peerLayoutAboutToChange);
+        connect(model->getPeerTableModel(), &PeerTableModel::layoutChanged, this, &RPCConsole::updateDetailWidget);
 
         // set up ban table
         ui->banlistWidget->setModel(model->getBanTableModel());
@@ -1014,67 +1012,6 @@ void RPCConsole::updateTrafficStats(quint64 totalBytesIn, quint64 totalBytesOut)
     ui->lblBytesOut->setText(GUIUtil::formatBytes(totalBytesOut));
 }
 
-void RPCConsole::peerLayoutAboutToChange()
-{
-    cachedNodeids.clear();
-    for (const QModelIndex& peer : GUIUtil::getEntryData(ui->peerWidget, PeerTableModel::NetNodeId)) {
-        const auto stats = peer.data(PeerTableModel::StatsRole).value<CNodeCombinedStats*>();
-        cachedNodeids.append(stats->nodeStats.nodeid);
-    }
-}
-
-void RPCConsole::peerLayoutChanged()
-{
-    if (!clientModel || !clientModel->getPeerTableModel())
-        return;
-
-    bool fUnselect = false;
-    bool fReselect = false;
-
-    if (cachedNodeids.empty()) // no node selected yet
-        return;
-
-    // find the currently selected row
-    int selectedRow = -1;
-    QModelIndexList selectedModelIndex = ui->peerWidget->selectionModel()->selectedIndexes();
-    if (!selectedModelIndex.isEmpty()) {
-        selectedRow = selectedModelIndex.first().row();
-    }
-
-    // check if our detail node has a row in the table (it may not necessarily
-    // be at selectedRow since its position can change after a layout change)
-    int detailNodeRow = clientModel->getPeerTableModel()->getRowByNodeId(cachedNodeids.first());
-
-    if (detailNodeRow < 0)
-    {
-        // detail node disappeared from table (node disconnected)
-        fUnselect = true;
-    }
-    else
-    {
-        if (detailNodeRow != selectedRow)
-        {
-            // detail node moved position
-            fUnselect = true;
-            fReselect = true;
-        }
-    }
-
-    if (fUnselect && selectedRow >= 0) {
-        clearSelectedNode();
-    }
-
-    if (fReselect)
-    {
-        for(int i = 0; i < cachedNodeids.size(); i++)
-        {
-            ui->peerWidget->selectRow(clientModel->getPeerTableModel()->getRowByNodeId(cachedNodeids.at(i)));
-        }
-    }
-
-    updateDetailWidget();
-}
-
 void RPCConsole::updateDetailWidget()
 {
     const QList<QModelIndex> selected_peers = GUIUtil::getEntryData(ui->peerWidget, PeerTableModel::NetNodeId);