public abstract class

ViewSpline

extends SplineSet

 java.lang.Object

androidx.constraintlayout.core.motion.utils.SplineSet

↳androidx.constraintlayout.motion.utils.ViewSpline

Subclasses:

ViewSpline.PathRotate, ViewSpline.CustomSet

Gradle dependencies

compile group: 'androidx.constraintlayout', name: 'constraintlayout', version: '2.2.0-alpha01'

  • groupId: androidx.constraintlayout
  • artifactId: constraintlayout
  • version: 2.2.0-alpha01

Artifact androidx.constraintlayout:constraintlayout:2.2.0-alpha01 it located at Google repository (https://maven.google.com/)

Androidx artifact mapping:

androidx.constraintlayout:constraintlayout com.android.support.constraint:constraint-layout

Summary

Fields
from SplineSetmCurveFit, mTimePoints[], mValues[]
Constructors
publicViewSpline()

Methods
public static ViewSplinemakeCustomSpline(java.lang.String str, <any> attrList)

public static ViewSplinemakeSpline(java.lang.String str)

public abstract voidsetProperty(View view, float t)

the main interface to setting a view property

from SplineSetget, getCurveFit, getSlope, makeCustomSpline, makeCustomSplineSet, makeSpline, setPoint, setProperty, setType, setup, toString
from java.lang.Objectclone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructors

public ViewSpline()

Methods

public static ViewSpline makeCustomSpline(java.lang.String str, <any> attrList)

Parameters:

str:
attrList:

Returns:

public static ViewSpline makeSpline(java.lang.String str)

Parameters:

str:

Returns:

public abstract void setProperty(View view, float t)

the main interface to setting a view property

Parameters:

view: the view
t: the point of time

Source

/*
 * Copyright (C) 2020 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.motion.utils;

import android.os.Build;
import android.util.Log;
import android.util.SparseArray;
import android.view.View;

import androidx.constraintlayout.core.motion.utils.CurveFit;
import androidx.constraintlayout.core.motion.utils.SplineSet;
import androidx.constraintlayout.motion.widget.Key;
import androidx.constraintlayout.motion.widget.MotionLayout;
import androidx.constraintlayout.widget.ConstraintAttribute;

import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

public abstract class ViewSpline extends SplineSet {
    private static final String TAG = "ViewSpline";

    /**
     * @TODO: add description
     * @param str
     * @param attrList
     * @return
     */
    public static ViewSpline makeCustomSpline(String str,
                                              SparseArray<ConstraintAttribute> attrList) {
        return new CustomSet(str, attrList);
    }

    /**
     * @TODO: add description
     * @param str
     * @return
     */
    public static ViewSpline makeSpline(String str) {
        switch (str) {
            case Key.ALPHA:
                return new AlphaSet();
            case Key.ELEVATION:
                return new ElevationSet();
            case Key.ROTATION:
                return new RotationSet();
            case Key.ROTATION_X:
                return new RotationXset();
            case Key.ROTATION_Y:
                return new RotationYset();
            case Key.PIVOT_X:
                return new PivotXset();
            case Key.PIVOT_Y:
                return new PivotYset();
            case Key.TRANSITION_PATH_ROTATE:
                return new PathRotate();
            case Key.SCALE_X:
                return new ScaleXset();
            case Key.SCALE_Y:
                return new ScaleYset();
            case Key.WAVE_OFFSET:
                return new AlphaSet();
            case Key.WAVE_VARIES_BY:
                return new AlphaSet();
            case Key.TRANSLATION_X:
                return new TranslationXset();
            case Key.TRANSLATION_Y:
                return new TranslationYset();
            case Key.TRANSLATION_Z:
                return new TranslationZset();
            case Key.PROGRESS:
                return new ProgressSet();

            default:
                return null;

        }
    }

    /**
     * the main interface to setting a view property
     * @param view the view
     * @param t the point of time
     */
    public abstract void setProperty(View view, float t);

    static class ElevationSet extends ViewSpline {
        @Override
        public void setProperty(View view, float t) {
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
                view.setElevation(get(t));
            }
        }
    }

    static class AlphaSet extends ViewSpline {
        @Override
        public void setProperty(View view, float t) {
            view.setAlpha(get(t));
        }
    }

    static class RotationSet extends ViewSpline {
        @Override
        public void setProperty(View view, float t) {
            view.setRotation(get(t));
        }
    }

    static class RotationXset extends ViewSpline {
        @Override
        public void setProperty(View view, float t) {
            view.setRotationX(get(t));
        }
    }

    static class RotationYset extends ViewSpline {
        @Override
        public void setProperty(View view, float t) {
            view.setRotationY(get(t));
        }
    }

    static class PivotXset extends ViewSpline {
        @Override
        public void setProperty(View view, float t) {
            view.setPivotX(get(t));
        }
    }

    static class PivotYset extends ViewSpline {
        @Override
        public void setProperty(View view, float t) {
            view.setPivotY(get(t));
        }
    }

    public static class PathRotate extends ViewSpline {
        @Override
        public void setProperty(View view, float t) {
        }

        /**
         * Use to set the rotation relative to the path
         * @param view the view to set
         * @param t the time point
         * @param dx the path velocity in x
         * @param dy the path velocity in y
         */
        public void setPathRotate(View view, float t, double dx, double dy) {
            view.setRotation(get(t) + (float) Math.toDegrees(Math.atan2(dy, dx)));
        }
    }

    static class ScaleXset extends ViewSpline {
        @Override
        public void setProperty(View view, float t) {
            view.setScaleX(get(t));
        }
    }

    static class ScaleYset extends ViewSpline {
        @Override
        public void setProperty(View view, float t) {
            view.setScaleY(get(t));
        }
    }

    static class TranslationXset extends ViewSpline {
        @Override
        public void setProperty(View view, float t) {
            view.setTranslationX(get(t));
        }
    }

    static class TranslationYset extends ViewSpline {
        @Override
        public void setProperty(View view, float t) {
            view.setTranslationY(get(t));
        }
    }

    static class TranslationZset extends ViewSpline {
        @Override
        public void setProperty(View view, float t) {
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
                view.setTranslationZ(get(t));
            }
        }
    }

    public static class CustomSet extends ViewSpline {
        String mAttributeName;
        SparseArray<ConstraintAttribute> mConstraintAttributeList;
        float[] mTempValues;

        public CustomSet(String attribute, SparseArray<ConstraintAttribute> attrList) {
            mAttributeName = attribute.split(",")[1];
            mConstraintAttributeList = attrList;
        }

        /**
         * @TODO: add description
         * @param curveType
         */
        public void setup(int curveType) {
            int size = mConstraintAttributeList.size();
            int dimensionality =
                    mConstraintAttributeList.valueAt(0).numberOfInterpolatedValues();
            double[] time = new double[size];
            mTempValues = new float[dimensionality];
            double[][] values = new double[size][dimensionality];
            for (int i = 0; i < size; i++) {

                int key = mConstraintAttributeList.keyAt(i);
                ConstraintAttribute ca = mConstraintAttributeList.valueAt(i);

                time[i] = key * 1E-2;
                ca.getValuesToInterpolate(mTempValues);
                for (int k = 0; k < mTempValues.length; k++) {
                    values[i][k] = mTempValues[k];
                }

            }
            mCurveFit = CurveFit.get(curveType, time, values);
        }

        /**
         * this call will throw RuntimeException
         * @param position the position
         * @param value the value
         */
        public void setPoint(int position, float value) {
            throw new RuntimeException("call of custom attribute setPoint");
        }

        /**
         * set the CustomAttribute
         * @param position
         * @param value
         */
        public void setPoint(int position, ConstraintAttribute value) {
            mConstraintAttributeList.append(position, value);
        }

        @Override
        public void setProperty(View view, float t) {
            mCurveFit.getPos(t, mTempValues);
            CustomSupport.setInterpolatedValue(mConstraintAttributeList.valueAt(0),
                    view, mTempValues);
        }
    }

    static class ProgressSet extends ViewSpline {
        boolean mNoMethod = false;

        @Override
        public void setProperty(View view, float t) {
            if (view instanceof MotionLayout) {
                ((MotionLayout) view).setProgress(get(t));
            } else {
                if (mNoMethod) {
                    return;
                }
                Method method = null;
                try {
                    method = view.getClass().getMethod("setProgress", Float.TYPE);
                } catch (NoSuchMethodException e) {
                    mNoMethod = true;
                }
                if (method != null) {
                    try {
                        method.invoke(view, get(t));
                    } catch (IllegalAccessException e) {
                        Log.e(TAG, "unable to setProgress", e);
                    } catch (InvocationTargetException e) {
                        Log.e(TAG, "unable to setProgress", e);
                    }
                }
            }

        }
    }

}