<!-- Describe the issue -->
Hello evryone, I get nothing when I click in open wallet, I am new to bitcoin and expect to show something.

![BitcoinIssue](https://user-images.githubusercontent.com/39341595/57179721-5024fc00-6e9e-11e9-80dd-af5e4345be48.png)

I'am using Bitcoin Core (both in testnet and mainnet, didn't work) 0.18 on window 10. 

{
    assert(!m_wallet_controller);
    assert(wallet_controller);
    m_wallet_controller = wallet_controller;
    connect(wallet_controller, &WalletController::walletAdded, this, &BitcoinGUI::addWallet);
    connect(wallet_controller, &WalletController::walletRemoved, this, &BitcoinGUI::removeWallet);
    for (WalletModel* wallet_model : m_wallet_controller->getWallets()) {
        addWallet(wallet_model);
    }
}
void BitcoinGUI::addWallet(WalletModel* walletModel)