Merge bitcoin-core/gui#342: wallet: Move wallets loading out from the main GUI thread

2fe69efbc607fdcc3657637d59a38cc5b4db2d05 qt, wallet: Drop no longer used WalletController::getOpenWallets() (Hennadii Stepanov)
f6991cb906e9dad7ff76a51e2b654f798d5c2ba6 qt, wallet: Add LoadWalletsActivity class (Hennadii Stepanov)
4a024fc310f136ce62c733fb1174b3a80ea25d0a qt, wallet, refactor: Move connection to QObject::deleteLater to ctor (Hennadii Stepanov)
f9b633eeab6e9ee405bba37573aed9aa83c51ea5 qt, wallet: Move activity progress dialog from data member to local (Hennadii Stepanov)

Pull request description:

  This PR improves the GUI responsiveness during initial wallets loading at startup (especially ones that have tons of txs), and shows a standard progress dialog for long loading:

  ![DeepinScreenshot_select-area_20210522230626](https://user-images.githubusercontent.com/32963518/119239625-0b3a9380-bb53-11eb-9a54-34980d8a1194.png)

  Fixes #247.

ACKs for top commit:
  ryanofsky:
    Code review ACK 2fe69efbc607fdcc3657637d59a38cc5b4db2d05. Just suggested changes since last review: squashing commits and dropping unused method (thanks!)
  shaavan:
    reACK 2fe69efbc607fdcc3657637d59a38cc5b4db2d05
  promag:
    Code review ACK 2fe69efbc607fdcc3657637d59a38cc5b4db2d05.

Tree-SHA512: 2ac3cb48886e0005fc36b3fd0c2b35abd557186be16db3145d753c34d94188e4f4ff14dc07fb0fb7558944f84498204a3988f8284fd56c6d85b47bc9081e71a6

1 files changed, 2 insertions, 6 deletions

diff --git a/src/qt/bitcoingui.cpp b/src/qt/bitcoingui.cpp
index af05f35759..610637360b 100644
--- a/src/qt/bitcoingui.cpp
+++ b/src/qt/bitcoingui.cpp
@@ -107,7 +107,6 @@ BitcoinGUI::BitcoinGUI(interfaces::Node& node, const PlatformStyle *_platformSty
         walletFrame = new WalletFrame(_platformStyle, this);
         connect(walletFrame, &WalletFrame::createWalletButtonClicked, [this] {
             auto activity = new CreateWalletActivity(getWalletController(), this);
-            connect(activity, &CreateWalletActivity::finished, activity, &QObject::deleteLater);
             activity->create();
         });
         connect(walletFrame, &WalletFrame::message, [this](const QString& title, const QString& message, unsigned int style) {
@@ -418,7 +417,6 @@ void BitcoinGUI::createActions()
                 connect(action, &QAction::triggered, [this, path] {
                     auto activity = new OpenWalletActivity(m_wallet_controller, this);
                     connect(activity, &OpenWalletActivity::opened, this, &BitcoinGUI::setCurrentWallet);
-                    connect(activity, &OpenWalletActivity::finished, activity, &QObject::deleteLater);
                     activity->open(path);
                 });
             }
@@ -433,7 +431,6 @@ void BitcoinGUI::createActions()
         connect(m_create_wallet_action, &QAction::triggered, [this] {
             auto activity = new CreateWalletActivity(m_wallet_controller, this);
             connect(activity, &CreateWalletActivity::created, this, &BitcoinGUI::setCurrentWallet);
-            connect(activity, &CreateWalletActivity::finished, activity, &QObject::deleteLater);
             activity->create();
         });
         connect(m_close_all_wallets_action, &QAction::triggered, [this] {
@@ -664,9 +661,8 @@ void BitcoinGUI::setWalletController(WalletController* wallet_controller)
     GUIUtil::ExceptionSafeConnect(wallet_controller, &WalletController::walletAdded, this, &BitcoinGUI::addWallet);
     connect(wallet_controller, &WalletController::walletRemoved, this, &BitcoinGUI::removeWallet);
 
-    for (WalletModel* wallet_model : m_wallet_controller->getOpenWallets()) {
-        addWallet(wallet_model);
-    }
+    auto activity = new LoadWalletsActivity(m_wallet_controller, this);
+    activity->load();
 }
 
 WalletController* BitcoinGUI::getWalletController()