qml: initial RbF bump fee feature

electrum/gui/qml/components/BumpFeeDialog.qml

@@ -0,0 +1,264 @@
+import QtQuick 2.6
+import QtQuick.Layouts 1.0
+import QtQuick.Controls 2.14
+import QtQuick.Controls.Material 2.0
+
+import org.electrum 1.0
+
+import "controls"
+
+ElDialog {
+    id: dialog
+
+    required property string txid
+    required property QtObject txfeebumper
+
+    signal txaccepted
+
+    title: qsTr('Bump Fee')
+
+    width: parent.width
+    height: parent.height
+    padding: 0
+
+    standardButtons: Dialog.Cancel
+
+    modal: true
+    parent: Overlay.overlay
+    Overlay.modal: Rectangle {
+        color: "#aa000000"
+    }
+
+    // function updateAmountText() {
+    //     btcValue.text = Config.formatSats(finalizer.effectiveAmount, false)
+    //     fiatValue.text = Daemon.fx.enabled
+    //         ? '(' + Daemon.fx.fiatValue(finalizer.effectiveAmount, false) + ' ' + Daemon.fx.fiatCurrency + ')'
+    //         : ''
+    // }
+
+    ColumnLayout {
+        width: parent.width
+        height: parent.height
+        spacing: 0
+
+        GridLayout {
+            Layout.preferredWidth: parent.width
+            Layout.leftMargin: constants.paddingLarge
+            Layout.rightMargin: constants.paddingLarge
+            columns: 2
+
+            Label {
+                text: qsTr('Old fee')
+                color: Material.accentColor
+            }
+
+            RowLayout {
+                Label {
+                    id: oldfee
+                    text: Config.formatSats(txfeebumper.oldfee)
+                }
+
+                Label {
+                    text: Config.baseUnit
+                    color: Material.accentColor
+                }
+            }
+
+            Label {
+                text: qsTr('Old fee rate')
+                color: Material.accentColor
+            }
+
+            RowLayout {
+                Label {
+                    id: oldfeeRate
+                    text: txfeebumper.oldfeeRate
+                }
+
+                Label {
+                    text: 'sat/vB'
+                    color: Material.accentColor
+                }
+            }
+
+            // Label {
+            //     id: amountLabel
+            //     text: qsTr('Amount to send')
+            //     color: Material.accentColor
+            // }
+            //
+            // RowLayout {
+            //     Layout.fillWidth: true
+            //     Label {
+            //         id: btcValue
+            //         font.bold: true
+            //     }
+            //
+            //     Label {
+            //         text: Config.baseUnit
+            //         color: Material.accentColor
+            //     }
+            //
+            //     Label {
+            //         id: fiatValue
+            //         Layout.fillWidth: true
+            //         font.pixelSize: constants.fontSizeMedium
+            //     }
+            //
+            //     Component.onCompleted: updateAmountText()
+            //     Connections {
+            //         target: finalizer
+            //         function onEffectiveAmountChanged() {
+            //             updateAmountText()
+            //         }
+            //     }
+            // }
+
+            Label {
+                text: qsTr('Mining fee')
+                color: Material.accentColor
+            }
+
+            RowLayout {
+                Label {
+                    id: fee
+                    text: txfeebumper.valid ? Config.formatSats(txfeebumper.fee) : ''
+                }
+
+                Label {
+                    visible: txfeebumper.valid
+                    text: Config.baseUnit
+                    color: Material.accentColor
+                }
+            }
+
+            Label {
+                text: qsTr('Fee rate')
+                color: Material.accentColor
+            }
+
+            RowLayout {
+                Label {
+                    id: feeRate
+                    text: txfeebumper.valid ? txfeebumper.feeRate : ''
+                }
+
+                Label {
+                    visible: txfeebumper.valid
+                    text: 'sat/vB'
+                    color: Material.accentColor
+                }
+            }
+
+            Label {
+                text: qsTr('Target')
+                color: Material.accentColor
+            }
+
+            Label {
+                id: targetdesc
+                text: txfeebumper.target
+            }
+
+            Slider {
+                id: feeslider
+                leftPadding: constants.paddingMedium
+                snapMode: Slider.SnapOnRelease
+                stepSize: 1
+                from: 0
+                to: txfeebumper.sliderSteps
+                onValueChanged: {
+                    if (activeFocus)
+                        txfeebumper.sliderPos = value
+                }
+                Component.onCompleted: {
+                    value = txfeebumper.sliderPos
+                }
+                Connections {
+                    target: txfeebumper
+                    function onSliderPosChanged() {
+                        feeslider.value = txfeebumper.sliderPos
+                    }
+                }
+            }
+
+            FeeMethodComboBox {
+                id: target
+                feeslider: txfeebumper
+            }
+
+            CheckBox {
+                id: final_cb
+                text: qsTr('Replace-by-Fee')
+                Layout.columnSpan: 2
+                checked: txfeebumper.rbf
+                onCheckedChanged: {
+                    if (activeFocus)
+                        txfeebumper.rbf = checked
+                }
+            }
+
+            InfoTextArea {
+                Layout.columnSpan: 2
+                Layout.preferredWidth: parent.width * 3/4
+                Layout.alignment: Qt.AlignHCenter
+                visible: txfeebumper.warning != ''
+                text: txfeebumper.warning
+                iconStyle: InfoTextArea.IconStyle.Warn
+            }
+
+            Label {
+                visible: txfeebumper.valid
+                text: qsTr('Outputs')
+                Layout.columnSpan: 2
+                color: Material.accentColor
+            }
+
+            Repeater {
+                model: txfeebumper.valid ? txfeebumper.outputs : []
+                delegate: TextHighlightPane {
+                    Layout.columnSpan: 2
+                    Layout.fillWidth: true
+                    padding: 0
+                    leftPadding: constants.paddingSmall
+                    RowLayout {
+                        width: parent.width
+                        Label {
+                            text: modelData.address
+                            Layout.fillWidth: true
+                            wrapMode: Text.Wrap
+                            font.pixelSize: constants.fontSizeLarge
+                            font.family: FixedFont
+                            color: modelData.is_mine ? constants.colorMine : Material.foreground
+                        }
+                        Label {
+                            text: Config.formatSats(modelData.value_sats)
+                            font.pixelSize: constants.fontSizeMedium
+                            font.family: FixedFont
+                        }
+                        Label {
+                            text: Config.baseUnit
+                            font.pixelSize: constants.fontSizeMedium
+                            color: Material.accentColor
+                        }
+                    }
+                }
+            }
+        }
+
+        Item { Layout.fillHeight: true; Layout.preferredWidth: 1 }
+
+        FlatButton {
+            id: sendButton
+            Layout.fillWidth: true
+            text: qsTr('Ok')
+            icon.source: '../../icons/confirmed.png'
+            enabled: txfeebumper.valid
+            onClicked: {
+                txaccepted()
+                dialog.close()
+            }
+        }
+    }
+
+}

electrum/gui/qml/components/ConfirmTxDialog.qml

@@ -155,31 +155,9 @@ ElDialog {
                 }
             }
 
-            ComboBox {
+            FeeMethodComboBox {
                 id: target
-                textRole: 'text'
-                valueRole: 'value'
-                model: [
-                    { text: qsTr('ETA'), value: 1 },
-                    { text: qsTr('Mempool'), value: 2 },
-                    { text: qsTr('Static'), value: 0 }
-                ]
-                onCurrentValueChanged: {
-                    if (activeFocus)
-                        finalizer.method = currentValue
-                }
-                Component.onCompleted: {
-                    currentIndex = indexOfValue(finalizer.method)
-                }
-            }
-
-            InfoTextArea {
-                Layout.columnSpan: 2
-                Layout.preferredWidth: parent.width * 3/4
-                Layout.alignment: Qt.AlignHCenter
-                visible: finalizer.warning != ''
-                text: finalizer.warning
-                iconStyle: InfoTextArea.IconStyle.Warn
+                feeslider: finalizer
             }
 
             CheckBox {
@@ -194,6 +172,15 @@ ElDialog {
                 }
             }
 
+            InfoTextArea {
+                Layout.columnSpan: 2
+                Layout.preferredWidth: parent.width * 3/4
+                Layout.alignment: Qt.AlignHCenter
+                visible: finalizer.warning != ''
+                text: finalizer.warning
+                iconStyle: InfoTextArea.IconStyle.Warn
+            }
+
             Label {
                 text: qsTr('Outputs')
                 Layout.columnSpan: 2

electrum/gui/qml/components/TxDetails.qml

@@ -28,7 +28,18 @@ Pane {
             action: Action {
                 text: qsTr('Bump fee')
                 enabled: txdetails.canBump
-                //onTriggered:
+                onTriggered: {
+                    var dialog = bumpFeeDialog.createObject(root, { txid: root.txid })
+                    dialog.open()
+                }
+            }
+        }
+        MenuItem {
+            icon.color: 'transparent'
+            action: Action {
+                text: qsTr('Child pays for parent')
+                enabled: txdetails.canCpfp
+                onTriggered: notificationPopup.show('Not implemented')
             }
         }
         MenuItem {
@@ -36,6 +47,15 @@ Pane {
             action: Action {
                 text: qsTr('Cancel double-spend')
                 enabled: txdetails.canCancel
+                onTriggered: notificationPopup.show('Not implemented')
+            }
+        }
+        MenuItem {
+            icon.color: 'transparent'
+            action: Action {
+                text: qsTr('Remove')
+                enabled: txdetails.canRemove
+                onTriggered: notificationPopup.show('Not implemented')
             }
         }
     }
@@ -349,4 +369,22 @@ Pane {
         rawtx: root.rawtx
         onLabelChanged: root.detailsChanged()
     }
+
+    Component {
+        id: bumpFeeDialog
+        BumpFeeDialog {
+            id: dialog
+            txfeebumper: TxFeeBumper {
+                id: txfeebumper
+                wallet: Daemon.currentWallet
+                txid: dialog.txid
+            }
+
+            onTxaccepted: {
+                root.rawtx = txfeebumper.getNewTx()
+            }
+            onClosed: destroy()
+        }
+    }
+
 }

electrum/gui/qml/components/controls/FeeMethodComboBox.qml

@@ -0,0 +1,26 @@
+import QtQuick 2.6
+import QtQuick.Controls 2.0
+
+import org.electrum 1.0
+
+ComboBox {
+    id: control
+
+    required property QtObject feeslider
+
+    textRole: 'text'
+    valueRole: 'value'
+
+    model: [
+        { text: qsTr('ETA'), value: 1 },
+        { text: qsTr('Mempool'), value: 2 },
+        { text: qsTr('Static'), value: 0 }
+    ]
+    onCurrentValueChanged: {
+        if (activeFocus)
+            feeslider.method = currentValue
+    }
+    Component.onCompleted: {
+        currentIndex = indexOfValue(feeslider.method)
+    }
+}

electrum/gui/qml/qeapp.py

@@ -19,7 +19,7 @@ from .qeqr import QEQRParser, QEQRImageProvider, QEQRImageProviderHelper
 from .qewalletdb import QEWalletDB
 from .qebitcoin import QEBitcoin
 from .qefx import QEFX
-from .qetxfinalizer import QETxFinalizer
+from .qetxfinalizer import QETxFinalizer, QETxFeeBumper
 from .qeinvoice import QEInvoice, QEInvoiceParser, QEUserEnteredPayment
 from .qerequestdetails import QERequestDetails
 from .qetypes import QEAmount
@@ -216,6 +216,7 @@ class ElectrumQmlApplication(QGuiApplication):
         qmlRegisterType(QEChannelDetails, 'org.electrum', 1, 0, 'ChannelDetails')
         qmlRegisterType(QESwapHelper, 'org.electrum', 1, 0, 'SwapHelper')
         qmlRegisterType(QERequestDetails, 'org.electrum', 1, 0, 'RequestDetails')
+        qmlRegisterType(QETxFeeBumper, 'org.electrum', 1, 0, 'TxFeeBumper')
 
         qmlRegisterUncreatableType(QEAmount, 'org.electrum', 1, 0, 'Amount', 'Amount can only be used as property')
         qmlRegisterUncreatableType(QENewWalletWizard, 'org.electrum', 1, 0, 'NewWalletWizard', 'NewWalletWizard can only be used as property')

electrum/gui/qml/qetxdetails.py

@@ -82,6 +82,8 @@ class QETxDetails(QObject):
         if self._rawtx != rawtx:
             self._logger.debug('rawtx set -> %s' % rawtx)
             self._rawtx = rawtx
+            if not rawtx:
+                return
             try:
                 self._tx = tx_from_any(rawtx, deserialize=True)
                 self._logger.debug('tx type is %s' % str(type(self._tx)))
@@ -209,7 +211,7 @@ class QETxDetails(QObject):
 
         txinfo = self._wallet.wallet.get_tx_info(self._tx)
 
-        #self._logger.debug(repr(txinfo))
+        self._logger.debug(repr(txinfo))
 
         # can be None if outputs unrelated to wallet seed,
         # e.g. to_local local_force_close commitment CSV-locked p2wsh script

electrum/gui/qml/qetxfinalizer.py

@@ -4,42 +4,23 @@ from PyQt5.QtCore import pyqtProperty, pyqtSignal, pyqtSlot, QObject
 
 from electrum.logging import get_logger
 from electrum.i18n import _
-from electrum.transaction import PartialTxOutput
+from electrum.transaction import PartialTxOutput, PartialTransaction
 from electrum.util import NotEnoughFunds, profiler
+from electrum.wallet import CannotBumpFee
 
 from .qewallet import QEWallet
 from .qetypes import QEAmount
 
-class QETxFinalizer(QObject):
-    def __init__(self, parent=None, *, make_tx=None, accept=None):
-        super().__init__(parent)
-        self.f_make_tx = make_tx
-        self.f_accept = accept
-        self._tx = None
-
-    _logger = get_logger(__name__)
-
-    _address = ''
-    _amount = QEAmount()
-    _effectiveAmount = QEAmount()
-    _fee = QEAmount()
-    _feeRate = ''
+class FeeSlider(QObject):
     _wallet = None
-    _valid = False
     _sliderSteps = 0
     _sliderPos = 0
     _method = -1
-    _warning = ''
     _target = ''
-    _rbf = False
-    _canRbf = False
-    _outputs = []
-    config = None
+    _config = None
 
-    validChanged = pyqtSignal()
-    @pyqtProperty(bool, notify=validChanged)
-    def valid(self):
-        return self._valid
+    def __init__(self, parent=None):
+        super().__init__(parent)
 
     walletChanged = pyqtSignal()
     @pyqtProperty(QEWallet, notify=walletChanged)
@@ -50,37 +31,106 @@ class QETxFinalizer(QObject):
     def wallet(self, wallet: QEWallet):
         if self._wallet != wallet:
             self._wallet = wallet
-            self.config = self._wallet.wallet.config
+            self._config = self._wallet.wallet.config
             self.read_config()
             self.walletChanged.emit()
 
-    addressChanged = pyqtSignal()
-    @pyqtProperty(str, notify=addressChanged)
-    def address(self):
-        return self._address
+    sliderStepsChanged = pyqtSignal()
+    @pyqtProperty(int, notify=sliderStepsChanged)
+    def sliderSteps(self):
+        return self._sliderSteps
 
-    @address.setter
-    def address(self, address):
-        if self._address != address:
-            self._address = address
-            self.addressChanged.emit()
+    sliderPosChanged = pyqtSignal()
+    @pyqtProperty(int, notify=sliderPosChanged)
+    def sliderPos(self):
+        return self._sliderPos
 
-    amountChanged = pyqtSignal()
-    @pyqtProperty(QEAmount, notify=amountChanged)
-    def amount(self):
-        return self._amount
+    @sliderPos.setter
+    def sliderPos(self, sliderPos):
+        if self._sliderPos != sliderPos:
+            self._sliderPos = sliderPos
+            self.save_config()
+            self.sliderPosChanged.emit()
 
-    @amount.setter
-    def amount(self, amount):
-        if self._amount != amount:
-            self._logger.debug(str(amount))
-            self._amount.copyFrom(amount)
-            self.amountChanged.emit()
+    methodChanged = pyqtSignal()
+    @pyqtProperty(int, notify=methodChanged)
+    def method(self):
+        return self._method
 
-    effectiveAmountChanged = pyqtSignal()
-    @pyqtProperty(QEAmount, notify=effectiveAmountChanged)
-    def effectiveAmount(self):
-        return self._effectiveAmount
+    @method.setter
+    def method(self, method):
+        if self._method != method:
+            self._method = method
+            self.update_slider()
+            self.methodChanged.emit()
+            self.save_config()
+
+    def get_method(self):
+        dynfees = self._method > 0
+        mempool = self._method == 2
+        return dynfees, mempool
+
+    targetChanged = pyqtSignal()
+    @pyqtProperty(str, notify=targetChanged)
+    def target(self):
+        return self._target
+
+    @target.setter
+    def target(self, target):
+        if self._target != target:
+            self._target = target
+            self.targetChanged.emit()
+
+    def update_slider(self):
+        dynfees, mempool = self.get_method()
+        maxp, pos, fee_rate = self._config.get_fee_slider(dynfees, mempool)
+        self._sliderSteps = maxp
+        self._sliderPos = pos
+        self.sliderStepsChanged.emit()
+        self.sliderPosChanged.emit()
+
+    def update_target(self):
+        target, tooltip, dyn = self._config.get_fee_target()
+        self.target = target
+
+    def read_config(self):
+        mempool = self._config.use_mempool_fees()
+        dynfees = self._config.is_dynfee()
+        self._method = (2 if mempool else 1) if dynfees else 0
+        self.update_slider()
+        self.methodChanged.emit()
+        self.update_target()
+        self.update()
+
+    def save_config(self):
+        value = int(self._sliderPos)
+        dynfees, mempool = self.get_method()
+        self._config.set_key('dynamic_fees', dynfees, False)
+        self._config.set_key('mempool_fees', mempool, False)
+        if dynfees:
+            if mempool:
+                self._config.set_key('depth_level', value, True)
+            else:
+                self._config.set_key('fee_level', value, True)
+        else:
+            self._config.set_key('fee_per_kb', self._config.static_fee(value), True)
+        self.update_target()
+        self.update()
+
+    def update(self):
+        raise NotImplementedError()
+
+class TxFeeSlider(FeeSlider):
+    _fee = QEAmount()
+    _feeRate = ''
+    _rbf = False
+    _tx = None
+    _outputs = []
+    _valid = False
+    _warning = ''
+
+    def __init__(self, parent=None):
+        super().__init__(parent)
 
     feeChanged = pyqtSignal()
     @pyqtProperty(QEAmount, notify=feeChanged)
@@ -104,17 +154,6 @@ class QETxFinalizer(QObject):
             self._feeRate = feeRate
             self.feeRateChanged.emit()
 
-    targetChanged = pyqtSignal()
-    @pyqtProperty(str, notify=targetChanged)
-    def target(self):
-        return self._target
-
-    @target.setter
-    def target(self, target):
-        if self._target != target:
-            self._target = target
-            self.targetChanged.emit()
-
     rbfChanged = pyqtSignal()
     @pyqtProperty(bool, notify=rbfChanged)
     def rbf(self):
@@ -127,19 +166,6 @@ class QETxFinalizer(QObject):
             self.update()
             self.rbfChanged.emit()
 
-    canRbfChanged = pyqtSignal()
-    @pyqtProperty(bool, notify=canRbfChanged)
-    def canRbf(self):
-        return self._canRbf
-
-    @canRbf.setter
-    def canRbf(self, canRbf):
-        if self._canRbf != canRbf:
-            self._canRbf = canRbf
-            self.canRbfChanged.emit()
-            if not canRbf and self.rbf:
-                self.rbf = False
-
     outputsChanged = pyqtSignal()
     @pyqtProperty('QVariantList', notify=outputsChanged)
     def outputs(self):
@@ -162,70 +188,81 @@ class QETxFinalizer(QObject):
             self._warning = warning
             self.warningChanged.emit()
 
-    sliderStepsChanged = pyqtSignal()
-    @pyqtProperty(int, notify=sliderStepsChanged)
-    def sliderSteps(self):
-        return self._sliderSteps
+    validChanged = pyqtSignal()
+    @pyqtProperty(bool, notify=validChanged)
+    def valid(self):
+        return self._valid
 
-    sliderPosChanged = pyqtSignal()
-    @pyqtProperty(int, notify=sliderPosChanged)
-    def sliderPos(self):
-        return self._sliderPos
+    def update_from_tx(self, tx):
+        tx_size = tx.estimated_size()
+        fee = tx.get_fee()
+        feerate = Decimal(fee) / tx_size  # sat/byte
 
-    @sliderPos.setter
-    def sliderPos(self, sliderPos):
-        if self._sliderPos != sliderPos:
-            self._sliderPos = sliderPos
-            self.save_config()
-            self.sliderPosChanged.emit()
+        self.fee = QEAmount(amount_sat=int(fee))
+        self.feeRate = f'{feerate:.1f}'
 
-    methodChanged = pyqtSignal()
-    @pyqtProperty(int, notify=methodChanged)
-    def method(self):
-        return self._method
+        outputs = []
+        for o in tx.outputs():
+            outputs.append({
+                'address': o.get_ui_address_str(),
+                'value_sats': o.value,
+                'is_mine': self._wallet.wallet.is_mine(o.get_ui_address_str())
+            })
+        self.outputs = outputs
 
-    @method.setter
-    def method(self, method):
-        if self._method != method:
-            self._method = method
-            self.update_slider()
-            self.methodChanged.emit()
-            self.save_config()
+class QETxFinalizer(TxFeeSlider):
+    def __init__(self, parent=None, *, make_tx=None, accept=None):
+        super().__init__(parent)
+        self.f_make_tx = make_tx
+        self.f_accept = accept
 
-    def get_method(self):
-        dynfees = self._method > 0
-        mempool = self._method == 2
-        return dynfees, mempool
+    _logger = get_logger(__name__)
 
-    def update_slider(self):
-        dynfees, mempool = self.get_method()
-        maxp, pos, fee_rate = self.config.get_fee_slider(dynfees, mempool)
-        self._sliderSteps = maxp
-        self._sliderPos = pos
-        self.sliderStepsChanged.emit()
-        self.sliderPosChanged.emit()
+    _address = ''
+    _amount = QEAmount()
+    _effectiveAmount = QEAmount()
+    _canRbf = False
 
-    def read_config(self):
-        mempool = self.config.use_mempool_fees()
-        dynfees = self.config.is_dynfee()
-        self._method = (2 if mempool else 1) if dynfees else 0
-        self.update_slider()
-        self.methodChanged.emit()
-        self.update()
+    addressChanged = pyqtSignal()
+    @pyqtProperty(str, notify=addressChanged)
+    def address(self):
+        return self._address
 
-    def save_config(self):
-        value = int(self._sliderPos)
-        dynfees, mempool = self.get_method()
-        self.config.set_key('dynamic_fees', dynfees, False)
-        self.config.set_key('mempool_fees', mempool, False)
-        if dynfees:
-            if mempool:
-                self.config.set_key('depth_level', value, True)
-            else:
-                self.config.set_key('fee_level', value, True)
-        else:
-            self.config.set_key('fee_per_kb', self.config.static_fee(value), True)
-        self.update()
+    @address.setter
+    def address(self, address):
+        if self._address != address:
+            self._address = address
+            self.addressChanged.emit()
+
+    amountChanged = pyqtSignal()
+    @pyqtProperty(QEAmount, notify=amountChanged)
+    def amount(self):
+        return self._amount
+
+    @amount.setter
+    def amount(self, amount):
+        if self._amount != amount:
+            self._logger.debug(str(amount))
+            self._amount.copyFrom(amount)
+            self.amountChanged.emit()
+
+    effectiveAmountChanged = pyqtSignal()
+    @pyqtProperty(QEAmount, notify=effectiveAmountChanged)
+    def effectiveAmount(self):
+        return self._effectiveAmount
+
+    canRbfChanged = pyqtSignal()
+    @pyqtProperty(bool, notify=canRbfChanged)
+    def canRbf(self):
+        return self._canRbf
+
+    @canRbf.setter
+    def canRbf(self, canRbf):
+        if self._canRbf != canRbf:
+            self._canRbf = canRbf
+            self.canRbfChanged.emit()
+            if not canRbf and self.rbf:
+                self.rbf = False
 
     @profiler
     def make_tx(self, amount):
@@ -241,18 +278,8 @@ class QETxFinalizer(QObject):
 
         self._logger.debug('fee: %d, inputs: %d, outputs: %d' % (tx.get_fee(), len(tx.inputs()), len(tx.outputs())))
 
-        outputs = []
-        for o in tx.outputs():
-            outputs.append({
-                'address': o.get_ui_address_str(),
-                'value_sats': o.value,
-                'is_mine': self._wallet.wallet.is_mine(o.get_ui_address_str())
-            })
-        self.outputs = outputs
-
         return tx
 
-    @pyqtSlot()
     def update(self):
         try:
             # make unsigned transaction
@@ -276,26 +303,18 @@ class QETxFinalizer(QObject):
         self._effectiveAmount.satsInt = amount
         self.effectiveAmountChanged.emit()
 
-        tx_size = tx.estimated_size()
-        fee = tx.get_fee()
-        feerate = Decimal(fee) / tx_size  # sat/byte
-
-        self._fee.satsInt = int(fee)
-        self.feeRate = f'{feerate:.1f}'
+        self.update_from_tx(tx)
 
         #TODO
         #x_fee = run_hook('get_tx_extra_fee', self._wallet.wallet, tx)
         fee_warning_tuple = self._wallet.wallet.get_tx_fee_warning(
-            invoice_amt=amount, tx_size=tx_size, fee=fee)
+            invoice_amt=amount, tx_size=tx.estimated_size(), fee=tx.get_fee())
         if fee_warning_tuple:
             allow_send, long_warning, short_warning = fee_warning_tuple
             self.warning = long_warning
         else:
             self.warning = ''
 
-        target, tooltip, dyn = self.config.get_fee_target()
-        self.target = target
-
         self._valid = True
         self.validChanged.emit()
 
@@ -318,3 +337,133 @@ class QETxFinalizer(QObject):
             return self._tx.to_qr_data()
         else:
             return str(self._tx)
+
+
+class QETxFeeBumper(TxFeeSlider):
+    _logger = get_logger(__name__)
+
+    _oldfee = QEAmount()
+    _oldfee_rate = 0
+    _orig_tx = None
+    _txid = ''
+    _rbf = True
+
+    def __init__(self, parent=None):
+        super().__init__(parent)
+
+    txidChanged = pyqtSignal()
+    @pyqtProperty(str, notify=txidChanged)
+    def txid(self):
+        return self._txid
+
+    @txid.setter
+    def txid(self, txid):
+        if self._txid != txid:
+            self._txid = txid
+            self.get_tx()
+            self.txidChanged.emit()
+
+    oldfeeChanged = pyqtSignal()
+    @pyqtProperty(QEAmount, notify=oldfeeChanged)
+    def oldfee(self):
+        return self._oldfee
+
+    @oldfee.setter
+    def oldfee(self, oldfee):
+        if self._oldfee != oldfee:
+            self._oldfee.copyFrom(oldfee)
+            self.oldfeeChanged.emit()
+
+    oldfeeRateChanged = pyqtSignal()
+    @pyqtProperty(str, notify=oldfeeRateChanged)
+    def oldfeeRate(self):
+        return self._oldfee_rate
+
+    @oldfeeRate.setter
+    def oldfeeRate(self, oldfeerate):
+        if self._oldfee_rate != oldfeerate:
+            self._oldfee_rate = oldfeerate
+            self.oldfeeRateChanged.emit()
+
+
+    def get_tx(self):
+        assert self._txid
+        self._orig_tx = self._wallet.wallet.get_input_tx(self._txid)
+        assert self._orig_tx
+
+        if not isinstance(self._orig_tx, PartialTransaction):
+            self._orig_tx = PartialTransaction.from_tx(self._orig_tx)
+
+        if not self._add_info_to_tx_from_wallet_and_network(self._orig_tx):
+            return
+
+        self.update_from_tx(self._orig_tx)
+
+        self.oldfee = self.fee
+        self.oldfeeRate = self.feeRate
+        self.update()
+
+    # TODO: duplicated from kivy gui, candidate for moving into backend wallet
+    def _add_info_to_tx_from_wallet_and_network(self, tx: PartialTransaction) -> bool:
+        """Returns whether successful."""
+        # note side-effect: tx is being mutated
+        assert isinstance(tx, PartialTransaction)
+        try:
+            # note: this might download input utxos over network
+            # FIXME network code in gui thread...
+            tx.add_info_from_wallet(self._wallet.wallet, ignore_network_issues=False)
+        except NetworkException as e:
+            # self.app.show_error(repr(e))
+            self._logger.error(repr(e))
+            return False
+        return True
+
+    def update(self):
+        if not self._txid:
+            # not initialized yet
+            return
+
+        fee_per_kb = self._config.fee_per_kb()
+        if fee_per_kb is None:
+            # dynamic method and no network
+            self._logger.debug('no fee_per_kb')
+            self.warning = _('Cannot determine dynamic fees, not connected')
+            return
+
+        new_fee_rate = fee_per_kb / 1000
+
+        try:
+            self._tx = self._wallet.wallet.bump_fee(
+                tx=self._orig_tx,
+                txid=self._txid,
+                new_fee_rate=new_fee_rate,
+            )
+        except CannotBumpFee as e:
+            self._valid = False
+            self.validChanged.emit()
+            self._logger.error(str(e))
+            self.warning = str(e)
+            return
+        else:
+            self.warning = ''
+
+        self._tx.set_rbf(self.rbf)
+
+        self.update_from_tx(self._tx)
+
+        # TODO: deduce amount sent?
+        # TODO: we don't handle send-max txs correctly yet
+        # fee_warning_tuple = self._wallet.wallet.get_tx_fee_warning(
+        #     invoice_amt=amount, tx_size=tx.estimated_size(), fee=tx.get_fee())
+        # if fee_warning_tuple:
+        #     allow_send, long_warning, short_warning = fee_warning_tuple
+        #     self.warning = long_warning
+        # else:
+        #     self.warning = ''
+
+        self._valid = True
+        self.validChanged.emit()
+
+    @pyqtSlot(result=str)
+    def getNewTx(self):
+        return str(self._tx)