GuidelineReference.java
/*
* Copyright (C) 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.constraintlayout.core.widgets.analyzer;
import androidx.constraintlayout.core.widgets.ConstraintWidget;
import androidx.constraintlayout.core.widgets.Guideline;
class GuidelineReference extends WidgetRun {
GuidelineReference(ConstraintWidget widget) {
super(widget);
widget.mHorizontalRun.clear();
widget.mVerticalRun.clear();
this.orientation = ((Guideline) widget).getOrientation();
}
@Override
void clear() {
start.clear();
}
@Override
void reset() {
start.resolved = false;
end.resolved = false;
}
@Override
boolean supportsWrapComputation() {
return false;
}
private void addDependency(
androidx.constraintlayout.core.widgets.analyzer.DependencyNode node) {
start.mDependencies.add(node);
node.mTargets.add(start);
}
@Override
public void update(Dependency dependency) {
if (!start.readyToSolve) {
return;
}
if (start.resolved) {
return;
}
// ready to solve, centering.
androidx.constraintlayout.core.widgets.analyzer.DependencyNode startTarget =
start.mTargets.get(0);
Guideline guideline = (Guideline) mWidget;
int startPos = (int) (0.5f + startTarget.value * guideline.getRelativePercent());
start.resolve(startPos);
}
@Override
void apply() {
Guideline guideline = (Guideline) mWidget;
int relativeBegin = guideline.getRelativeBegin();
int relativeEnd = guideline.getRelativeEnd();
@SuppressWarnings("unused") float percent = guideline.getRelativePercent();
if (guideline.getOrientation() == ConstraintWidget.VERTICAL) {
if (relativeBegin != -1) {
start.mTargets.add(mWidget.mParent.mHorizontalRun.start);
mWidget.mParent.mHorizontalRun.start.mDependencies.add(start);
start.mMargin = relativeBegin;
} else if (relativeEnd != -1) {
start.mTargets.add(mWidget.mParent.mHorizontalRun.end);
mWidget.mParent.mHorizontalRun.end.mDependencies.add(start);
start.mMargin = -relativeEnd;
} else {
start.delegateToWidgetRun = true;
start.mTargets.add(mWidget.mParent.mHorizontalRun.end);
mWidget.mParent.mHorizontalRun.end.mDependencies.add(start);
}
// FIXME -- if we move the DependencyNode directly
// in the ConstraintAnchor we'll be good.
addDependency(mWidget.mHorizontalRun.start);
addDependency(mWidget.mHorizontalRun.end);
} else {
if (relativeBegin != -1) {
start.mTargets.add(mWidget.mParent.mVerticalRun.start);
mWidget.mParent.mVerticalRun.start.mDependencies.add(start);
start.mMargin = relativeBegin;
} else if (relativeEnd != -1) {
start.mTargets.add(mWidget.mParent.mVerticalRun.end);
mWidget.mParent.mVerticalRun.end.mDependencies.add(start);
start.mMargin = -relativeEnd;
} else {
start.delegateToWidgetRun = true;
start.mTargets.add(mWidget.mParent.mVerticalRun.end);
mWidget.mParent.mVerticalRun.end.mDependencies.add(start);
}
// FIXME -- if we move the DependencyNode directly
// in the ConstraintAnchor we'll be good.
addDependency(mWidget.mVerticalRun.start);
addDependency(mWidget.mVerticalRun.end);
}
}
@Override
public void applyToWidget() {
Guideline guideline = (Guideline) mWidget;
if (guideline.getOrientation() == ConstraintWidget.VERTICAL) {
mWidget.setX(start.value);
} else {
mWidget.setY(start.value);
}
}
}