Unity 8
RotationStates.qml
1 /*
2  * Copyright (C) 2015,2016 Canonical, Ltd.
3  *
4  * This program is free software; you can redistribute it and/or modify
5  * it under the terms of the GNU General Public License as published by
6  * the Free Software Foundation; version 3.
7  *
8  * This program is distributed in the hope that it will be useful,
9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11  * GNU General Public License for more details.
12  *
13  * You should have received a copy of the GNU General Public License
14  * along with this program. If not, see <http://www.gnu.org/licenses/>.
15  */
16 
17 import QtQuick 2.12
18 import Ubuntu.Components 1.3
19 import Powerd 0.1
20 
21 // Why the state machine is done that way:
22 // We cannot use regular PropertyChanges{} inside the State elements as steps in the
23 // transition animations must take place in a well defined order.
24 // Which means that we also cannot jump to a new state in the middle of a transition
25 // as that would make hell brake loose.
26 StateGroup {
27  id: root
28 
29  // to be set from the outside
30  property Item orientedShell
31  property Item shell
32  property Item shellCover
33  property Item shellSnapshot
34 
35  property int rotationDuration: 450
36  property int rotationEasing: Easing.InOutCubic
37  // Those values are good for debugging/development
38  //property int rotationDuration: 3000
39  //property int rotationEasing: Easing.Linear
40 
41  state: "0"
42  states: [
43  State { name: "0" },
44  State { name: "90" },
45  State { name: "180" },
46  State { name: "270" }
47  ]
48 
49  property QtObject d: QtObject {
50  id: d
51 
52  property bool startingUp: true
53  property var finishStartUpTimer: Timer {
54  interval: 500
55  onTriggered: d.startingUp = false
56  }
57  Component.onCompleted: {
58  finishStartUpTimer.start();
59  }
60 
61  property bool transitioning: false
62  onTransitioningChanged: {
63  d.tryUpdateState();
64  }
65 
66  readonly property int requestedOrientationAngle: root.orientedShell.acceptedOrientationAngle
67 
68  // Avoiding a direct call to tryUpdateState() as the state change might trigger an immediate
69  // change to Shell.orientationAngle which, in its turn, causes a reevaluation of
70  // requestedOrientationAngle (ie., OrientedShell.acceptedOrientationAngle). A reentrant evaluation
71  // of a binding is detected by QML as a binding loop and QML will deny the reevalutation, which
72  // will leave us in a bogus state.
73  //
74  // To avoid this mess we update the state in the next event loop iteration, ensuring a clean
75  // call stack.
76  onRequestedOrientationAngleChanged: {
77  stateUpdateTimer.start();
78  }
79  property Timer stateUpdateTimer: Timer {
80  id: stateUpdateTimer
81  interval: 1
82  onTriggered: { d.tryUpdateState(); }
83  }
84 
85  function tryUpdateState() {
86  if (d.transitioning || (!d.startingUp && !root.orientedShell.orientationChangesEnabled)) {
87  return;
88  }
89 
90  var requestedState = d.requestedOrientationAngle.toString();
91  if (requestedState === root.state) {
92  return;
93  }
94 
95  d.resolveAnimationType();
96 
97  var angleDiff = Math.abs(root.shell.orientationAngle - d.requestedOrientationAngle);
98  var isNinetyRotationAnimation = angleDiff == 90 || angleDiff == 270;
99  var needsShellSnapshot = d.animationType == d.fullAnimation && isNinetyRotationAnimation;
100 
101  if (needsShellSnapshot && !shellSnapshotReady) {
102  root.shellSnapshot.take();
103  // try again once we have a shell snapshot ready for use. Snapshot taking is async.
104  return;
105  }
106 
107  if (!needsShellSnapshot && shellSnapshotReady) {
108  root.shellSnapshot.discard();
109  }
110 
111  root.state = requestedState;
112  }
113 
114  property bool shellSnapshotReady: root.shellSnapshot && root.shellSnapshot.ready
115  onShellSnapshotReadyChanged: tryUpdateState();
116 
117  property Connections shellConnections: Connections {
118  target: root.orientedShell
119  onOrientationChangesEnabledChanged: {
120  d.tryUpdateState();
121  }
122  }
123 
124  readonly property int fullAnimation: 0
125  readonly property int indicatorsBarAnimation: 1
126  readonly property int noAnimation: 2
127 
128  property int animationType
129 
130  // animationType update *must* take place *before* the state update.
131  // If animationType and state were updated through bindings, as with normal qml code,
132  // there would be no guarantee in the order of the binding updates, which could then
133  // cause the wrong transitions to be chosen for the state changes.
134  function resolveAnimationType() {
135  if (d.startingUp) {
136  // During start up, inital property values are still settling while we're still
137  // to render the very first frame
138  d.animationType = d.noAnimation;
139  } else if (Powerd.status === Powerd.Off) {
140  // There's no point in animating if the user can't see it (display is off).
141  d.animationType = d.noAnimation;
142  } else {
143  if (!root.shell.mainApp) {
144  // shouldn't happen but, anyway
145  d.animationType = d.fullAnimation;
146  return;
147  }
148 
149  if (root.shell.mainApp.rotatesWindowContents) {
150  // The application will animate its own GUI, so we don't have to do anything ourselves.
151  d.animationType = d.noAnimation;
152  } else if (root.shell.mainAppWindowOrientationAngle == d.requestedOrientationAngle) {
153  // The app window is already on its final orientation angle.
154  // So we just animate the indicators bar
155  // TODO: what if the app is fullscreen?
156  d.animationType = d.indicatorsBarAnimation;
157  } else {
158  d.animationType = d.fullAnimation;
159  }
160  }
161  }
162 
163  // When an application switch takes place, d.requestedOrientationAngle and
164  // root.shell.mainAppWindowOrientationAngle get updated separately, at different moments.
165  // So, when one of those properties change, we shouldn't make a decision straight away
166  // as the other might be stale and about to be changed. So let's give it a bit of time for
167  // them to get properly updated.
168  // This approach is indeed a bit hacky.
169  property bool appWindowOrientationAngleNeedsUpdateUnstable:
170  root.shell.orientationAngle === d.requestedOrientationAngle
171  && root.shell.mainApp
172  && root.shell.mainAppWindowOrientationAngle !== root.shell.orientationAngle
173  && !d.transitioning
174  onAppWindowOrientationAngleNeedsUpdateUnstableChanged: {
175  stableTimer.restart();
176  }
177  property Timer stableTimer: Timer {
178  interval: 200
179  onTriggered: {
180  if (d.appWindowOrientationAngleNeedsUpdateUnstable) {
181  shell.updateFocusedAppOrientationAnimated();
182  }
183  }
184  }
185  }
186 
187  transitions: [
188  Transition {
189  from: "90"; to: "0"
190  enabled: d.animationType == d.fullAnimation
191  NinetyRotationAnimation { fromAngle: 90; toAngle: 0
192  info: d; shell: root.shell }
193  },
194  Transition {
195  from: "0"; to: "90"
196  enabled: d.animationType == d.fullAnimation
197  NinetyRotationAnimation { fromAngle: 0; toAngle: 90
198  info: d; shell: root.shell }
199  },
200  Transition {
201  from: "0"; to: "270"
202  enabled: d.animationType == d.fullAnimation
203  NinetyRotationAnimation { fromAngle: 0; toAngle: 270
204  info: d; shell: root.shell }
205  },
206  Transition {
207  from: "270"; to: "0"
208  enabled: d.animationType == d.fullAnimation
209  NinetyRotationAnimation { fromAngle: 270; toAngle: 0
210  info: d; shell: root.shell }
211  },
212  Transition {
213  from: "90"; to: "180"
214  enabled: d.animationType == d.fullAnimation
215  NinetyRotationAnimation { fromAngle: 90; toAngle: 180
216  info: d; shell: root.shell }
217  },
218  Transition {
219  from: "180"; to: "90"
220  enabled: d.animationType == d.fullAnimation
221  NinetyRotationAnimation { fromAngle: 180; toAngle: 90
222  info: d; shell: root.shell }
223  },
224  Transition {
225  from: "180"; to: "270"
226  enabled: d.animationType == d.fullAnimation
227  NinetyRotationAnimation { fromAngle: 180; toAngle: 270
228  info: d; shell: root.shell }
229  },
230  Transition {
231  from: "270"; to: "180"
232  enabled: d.animationType == d.fullAnimation
233  NinetyRotationAnimation { fromAngle: 270; toAngle: 180
234  info: d; shell: root.shell }
235  },
236  Transition {
237  from: "0"; to: "180"
238  enabled: d.animationType == d.fullAnimation
239  HalfLoopRotationAnimation { fromAngle: 0; toAngle: 180
240  info: d; shell: root.shell }
241  },
242  Transition {
243  from: "180"; to: "0"
244  enabled: d.animationType == d.fullAnimation
245  HalfLoopRotationAnimation { fromAngle: 180; toAngle: 0
246  info: d; shell: root.shell }
247  },
248  Transition {
249  from: "90"; to: "270"
250  enabled: d.animationType == d.fullAnimation
251  HalfLoopRotationAnimation { fromAngle: 90; toAngle: 270
252  info: d; shell: root.shell }
253  },
254  Transition {
255  from: "270"; to: "90"
256  enabled: d.animationType == d.fullAnimation
257  HalfLoopRotationAnimation { fromAngle: 270; toAngle: 90
258  info: d; shell: root.shell }
259  },
260  Transition {
261  objectName: "immediateTransition"
262  enabled: d.animationType == d.noAnimation
263  ImmediateRotationAction { info: d; shell: root.shell }
264  },
265  Transition {
266  enabled: d.animationType == d.indicatorsBarAnimation
267  SequentialAnimation {
268  ScriptAction { script: {
269  d.transitioning = true;
270  } }
271  NumberAnimation {
272  duration: UbuntuAnimation.FastDuration; easing: UbuntuAnimation.StandardEasing
273  target: root.shell; property: "panelAreaShowProgress"
274  from: 1.0; to: 0.0
275  }
276  ImmediateRotationAction { info: d; shell: root.shell }
277  NumberAnimation {
278  duration: UbuntuAnimation.FastDuration; easing: UbuntuAnimation.StandardEasing
279  target: root.shell; property: "panelAreaShowProgress"
280  from: 0.0; to: 1.0
281  }
282  ScriptAction { script: {
283  d.transitioning = false;
284  }}
285  }
286  }
287  ]
288 
289 }