| /* |
| * Copyright 2019 The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| package androidx.ui.text |
| |
| import androidx.compose.Composable |
| import androidx.compose.emptyContent |
| import androidx.compose.getValue |
| import androidx.compose.mutableStateOf |
| import androidx.compose.onDispose |
| import androidx.compose.remember |
| import androidx.compose.setValue |
| import androidx.compose.state |
| import androidx.ui.core.DensityAmbient |
| import androidx.ui.core.FontLoaderAmbient |
| import androidx.ui.core.Layout |
| import androidx.ui.core.LayoutCoordinates |
| import androidx.ui.core.Modifier |
| import androidx.ui.core.PassThroughLayout |
| import androidx.ui.core.TextInputServiceAmbient |
| import androidx.ui.core.drawBehind |
| import androidx.ui.core.gesture.DragObserver |
| import androidx.ui.core.gesture.dragGestureFilter |
| import androidx.ui.core.gesture.pressIndicatorGestureFilter |
| import androidx.ui.core.onPositioned |
| import androidx.ui.core.focus.FocusModifier |
| import androidx.ui.core.focus.FocusState |
| import androidx.ui.core.focus.focusState |
| import androidx.ui.graphics.painter.drawCanvas |
| import androidx.ui.input.EditProcessor |
| import androidx.ui.input.EditorValue |
| import androidx.ui.input.ImeAction |
| import androidx.ui.input.KeyboardType |
| import androidx.ui.input.NO_SESSION |
| import androidx.ui.input.VisualTransformation |
| import androidx.ui.semantics.Semantics |
| import androidx.ui.semantics.onClick |
| import androidx.ui.unit.PxPosition |
| import androidx.ui.unit.round |
| |
| /** |
| * The common TextField implementation. |
| */ |
| @Composable |
| fun CoreTextField( |
| value: EditorValue, |
| modifier: Modifier, |
| onValueChange: (EditorValue) -> Unit, |
| textStyle: TextStyle = TextStyle.Default, |
| keyboardType: KeyboardType = KeyboardType.Text, |
| imeAction: ImeAction = ImeAction.Unspecified, |
| onFocusChange: (Boolean) -> Unit = {}, |
| onImeActionPerformed: (ImeAction) -> Unit = {}, |
| visualTransformation: VisualTransformation = VisualTransformation.None, |
| onTextLayout: (TextLayoutResult) -> Unit = {}, |
| onTextInputStarted: (SoftwareKeyboardController) -> Unit = {} |
| ) { |
| // If developer doesn't pass new value to TextField, recompose won't happen but internal state |
| // and IME may think it is updated. To fix this inconsistent state, enforce recompose by |
| // incrementing generation counter when we callback to the developer and reset the state with |
| // the latest state. |
| val generation = state { 0 } |
| val Wrapper: @Composable (Int, @Composable () -> Unit) -> Unit = { _, child -> child() } |
| val onValueChangeWrapper: (EditorValue) -> Unit = { onValueChange(it); generation.value++ } |
| |
| Wrapper(generation.value) { |
| // Ambients |
| val textInputService = TextInputServiceAmbient.current |
| val density = DensityAmbient.current |
| val resourceLoader = FontLoaderAmbient.current |
| |
| // State |
| val (visualText, offsetMap) = remember(value, visualTransformation) { |
| val transformed = visualTransformation.filter(AnnotatedString(value.text)) |
| value.composition?.let { |
| TextFieldDelegate.applyCompositionDecoration(it, transformed) |
| } ?: transformed |
| } |
| val state = remember { |
| TextFieldState( |
| TextDelegate( |
| text = visualText, |
| style = textStyle, |
| density = density, |
| resourceLoader = resourceLoader |
| ) |
| ) |
| } |
| state.textDelegate = updateTextDelegate( |
| current = state.textDelegate, |
| text = visualText, |
| style = textStyle, |
| density = density, |
| resourceLoader = resourceLoader |
| ) |
| |
| // TODO: Stop lookup FocusModifier from modifier chain. (b/155434146) |
| var focusModifier: FocusModifier? = null |
| modifier.foldIn(Unit) { _, element -> |
| if (element is FocusModifier) { |
| focusModifier = element |
| return@foldIn |
| } |
| } |
| |
| val updatedModifier = if (focusModifier == null) { |
| modifier + FocusModifier().also { focusModifier = it } |
| } else { |
| modifier |
| } |
| |
| state.processor.onNewState(value, textInputService, state.inputSession) |
| TextInputEventObserver( |
| focusModifier = focusModifier!!, |
| onPress = { }, |
| onFocus = { |
| state.hasFocus = true |
| state.inputSession = TextFieldDelegate.onFocus( |
| textInputService, |
| value, |
| state.processor, |
| keyboardType, |
| imeAction, |
| onValueChangeWrapper, |
| onImeActionPerformed |
| ) |
| if (state.inputSession != NO_SESSION && textInputService != null) { |
| onTextInputStarted( |
| SoftwareKeyboardController( |
| textInputService, |
| state.inputSession |
| ) |
| ) |
| } |
| state.layoutCoordinates?.let { coords -> |
| textInputService?.let { textInputService -> |
| state.layoutResult?.let { layoutResult -> |
| TextFieldDelegate.notifyFocusedRect( |
| value, |
| state.textDelegate, |
| layoutResult, |
| coords, |
| textInputService, |
| state.inputSession, |
| state.hasFocus, |
| offsetMap |
| ) |
| } |
| } |
| } |
| onFocusChange(true) |
| }, |
| onBlur = { hasNextClient -> |
| state.hasFocus = false |
| TextFieldDelegate.onBlur( |
| textInputService, |
| state.inputSession, |
| state.processor, |
| hasNextClient, |
| onValueChangeWrapper |
| ) |
| onFocusChange(false) |
| }, |
| onRelease = { |
| state.layoutResult?.let { layoutResult -> |
| TextFieldDelegate.onRelease( |
| it, |
| layoutResult, |
| state.processor, |
| offsetMap, |
| onValueChangeWrapper, |
| textInputService, |
| state.inputSession, |
| state.hasFocus |
| ) |
| } |
| } |
| ) { |
| Layout( |
| emptyContent(), |
| updatedModifier.drawBehind { |
| state.layoutResult?.let { layoutResult -> |
| drawCanvas { canvas, _ -> |
| TextFieldDelegate.draw( |
| canvas, |
| value, |
| offsetMap, |
| layoutResult, |
| DefaultSelectionColor |
| ) |
| } |
| } |
| }.onPositioned { |
| if (textInputService != null) { |
| state.layoutCoordinates = it |
| state.layoutResult?.let { layoutResult -> |
| TextFieldDelegate.notifyFocusedRect( |
| value, |
| state.textDelegate, |
| layoutResult, |
| it, |
| textInputService, |
| state.inputSession, |
| state.hasFocus, |
| offsetMap |
| ) |
| } |
| } |
| } |
| ) { _, constraints, layoutDirection -> |
| TextFieldDelegate.layout( |
| state.textDelegate, |
| constraints, |
| layoutDirection, |
| state.layoutResult |
| ).let { (width, height, result) -> |
| if (state.layoutResult != result) { |
| state.layoutResult = result |
| onTextLayout(result) |
| } |
| layout( |
| width, |
| height, |
| mapOf( |
| FirstBaseline to result.firstBaseline.round(), |
| LastBaseline to result.lastBaseline.round() |
| ) |
| ) {} |
| } |
| } |
| } |
| } |
| } |
| |
| private class TextFieldState( |
| var textDelegate: TextDelegate |
| ) { |
| val processor = EditProcessor() |
| var inputSession = NO_SESSION |
| /** |
| * This should be a state as every time we update the value we need to redraw it. |
| * state observation during onDraw callback will make it work. |
| */ |
| var hasFocus by mutableStateOf(false) |
| /** The last layout coordinates for the Text's layout, used by selection */ |
| var layoutCoordinates: LayoutCoordinates? = null |
| /** The latest TextLayoutResult calculated in the measure block */ |
| var layoutResult: TextLayoutResult? = null |
| } |
| |
| /** |
| * Helper composable for observing all text input related events. |
| */ |
| @Composable |
| private fun TextInputEventObserver( |
| onPress: (PxPosition) -> Unit, |
| onRelease: (PxPosition) -> Unit, |
| onFocus: () -> Unit, |
| onBlur: (hasNextClient: Boolean) -> Unit, |
| focusModifier: FocusModifier, |
| children: @Composable () -> Unit |
| ) { |
| val prevState = state { FocusState.NotFocused } |
| if (focusModifier.focusState == FocusState.Focused && |
| prevState.value == FocusState.NotFocused |
| ) { |
| onFocus() |
| } |
| |
| if (focusModifier.focusState == FocusState.NotFocused && |
| prevState.value == FocusState.Focused |
| ) { |
| onBlur(false) // TODO: Need to know if there is next focus element |
| } |
| |
| prevState.value = focusModifier.focusState |
| |
| val doFocusIn = { |
| if (focusModifier.focusState == FocusState.NotFocused) { |
| focusModifier.requestFocus() |
| } |
| } |
| |
| onDispose { |
| onBlur(false) |
| } |
| |
| Semantics( |
| container = true, |
| mergeAllDescendants = true, |
| properties = { |
| onClick(action = { doFocusIn(); return@onClick true }) |
| } |
| ) { |
| val drag = Modifier.dragPositionGestureFilter( |
| onPress = { |
| if (focusModifier.focusState == FocusState.Focused) { |
| onPress(it) |
| } else { |
| doFocusIn() |
| } |
| }, |
| onRelease = onRelease |
| ) |
| |
| // TODO(b/150706555): This layout is temporary and should be removed once Semantics |
| // is implemented with modifiers. |
| @Suppress("DEPRECATION") |
| PassThroughLayout(drag, children) |
| } |
| } |
| |
| /** |
| * Helper class for tracking dragging event. |
| */ |
| internal class DragEventTracker { |
| private var origin = PxPosition.Origin |
| private var distance = PxPosition.Origin |
| |
| /** |
| * Restart the tracking from given origin. |
| * |
| * @param origin The origin of the drag gesture. |
| */ |
| fun init(origin: PxPosition) { |
| this.origin = origin |
| } |
| |
| /** |
| * Pass distance parameter called by DragGestureDetector$onDrag callback |
| * |
| * @param distance The distance from the origin of the drag origin. |
| */ |
| fun onDrag(distance: PxPosition) { |
| this.distance = distance |
| } |
| |
| /** |
| * Returns the current position. |
| * |
| * @return The position of the current drag point. |
| */ |
| fun getPosition(): PxPosition { |
| return origin + distance |
| } |
| } |
| |
| /** |
| * Helper composable for tracking drag position. |
| */ |
| @Composable |
| private fun Modifier.dragPositionGestureFilter( |
| onPress: (PxPosition) -> Unit, |
| onRelease: (PxPosition) -> Unit |
| ): Modifier { |
| val tracker = state { DragEventTracker() } |
| // TODO(shepshapard): PressIndicator doesn't seem to be the right thing to use here. It |
| // actually may be functionally correct, but might mostly suggest that it should not |
| // actually be called PressIndicator, but instead something else. |
| |
| return this |
| .pressIndicatorGestureFilter( |
| onStart = { |
| tracker.value.init(it) |
| onPress(it) |
| }, onStop = { |
| onRelease(tracker.value.getPosition()) |
| }) |
| .dragGestureFilter(dragObserver = object : |
| DragObserver { |
| override fun onDrag(dragDistance: PxPosition): PxPosition { |
| tracker.value.onDrag(dragDistance) |
| return PxPosition.Origin |
| } |
| }) |
| } |