| /* |
| * Copyright (C) 2007 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 android.graphics; |
| |
| import android.annotation.ColorInt; |
| import android.annotation.NonNull; |
| import android.annotation.Nullable; |
| |
| public class LinearGradient extends Shader { |
| |
| private static final int TYPE_COLORS_AND_POSITIONS = 1; |
| private static final int TYPE_COLOR_START_AND_COLOR_END = 2; |
| |
| /** |
| * Type of the LinearGradient: can be either TYPE_COLORS_AND_POSITIONS or |
| * TYPE_COLOR_START_AND_COLOR_END. |
| */ |
| private int mType; |
| |
| private float mX0; |
| private float mY0; |
| private float mX1; |
| private float mY1; |
| private int[] mColors; |
| private float[] mPositions; |
| private int mColor0; |
| private int mColor1; |
| |
| private TileMode mTileMode; |
| |
| /** |
| * Create a shader that draws a linear gradient along a line. |
| * |
| * @param x0 The x-coordinate for the start of the gradient line |
| * @param y0 The y-coordinate for the start of the gradient line |
| * @param x1 The x-coordinate for the end of the gradient line |
| * @param y1 The y-coordinate for the end of the gradient line |
| * @param colors The colors to be distributed along the gradient line |
| * @param positions May be null. The relative positions [0..1] of |
| * each corresponding color in the colors array. If this is null, |
| * the the colors are distributed evenly along the gradient line. |
| * @param tile The Shader tiling mode |
| */ |
| public LinearGradient(float x0, float y0, float x1, float y1, @NonNull @ColorInt int colors[], |
| @Nullable float positions[], @NonNull TileMode tile) { |
| if (colors.length < 2) { |
| throw new IllegalArgumentException("needs >= 2 number of colors"); |
| } |
| if (positions != null && colors.length != positions.length) { |
| throw new IllegalArgumentException("color and position arrays must be of equal length"); |
| } |
| mType = TYPE_COLORS_AND_POSITIONS; |
| mX0 = x0; |
| mY0 = y0; |
| mX1 = x1; |
| mY1 = y1; |
| mColors = colors.clone(); |
| mPositions = positions != null ? positions.clone() : null; |
| mTileMode = tile; |
| } |
| |
| /** |
| * Create a shader that draws a linear gradient along a line. |
| * |
| * @param x0 The x-coordinate for the start of the gradient line |
| * @param y0 The y-coordinate for the start of the gradient line |
| * @param x1 The x-coordinate for the end of the gradient line |
| * @param y1 The y-coordinate for the end of the gradient line |
| * @param color0 The color at the start of the gradient line. |
| * @param color1 The color at the end of the gradient line. |
| * @param tile The Shader tiling mode |
| */ |
| public LinearGradient(float x0, float y0, float x1, float y1, |
| @ColorInt int color0, @ColorInt int color1, |
| @NonNull TileMode tile) { |
| mType = TYPE_COLOR_START_AND_COLOR_END; |
| mX0 = x0; |
| mY0 = y0; |
| mX1 = x1; |
| mY1 = y1; |
| mColor0 = color0; |
| mColor1 = color1; |
| mColors = null; |
| mPositions = null; |
| mTileMode = tile; |
| } |
| |
| @Override |
| long createNativeInstance(long nativeMatrix) { |
| if (mType == TYPE_COLORS_AND_POSITIONS) { |
| return nativeCreate1(nativeMatrix, mX0, mY0, mX1, mY1, |
| mColors, mPositions, mTileMode.nativeInt); |
| } else { // TYPE_COLOR_START_AND_COLOR_END |
| return nativeCreate2(nativeMatrix, mX0, mY0, mX1, mY1, |
| mColor0, mColor1, mTileMode.nativeInt); |
| } |
| } |
| |
| /** |
| * @hide |
| */ |
| @Override |
| protected Shader copy() { |
| final LinearGradient copy; |
| if (mType == TYPE_COLORS_AND_POSITIONS) { |
| copy = new LinearGradient(mX0, mY0, mX1, mY1, mColors.clone(), |
| mPositions != null ? mPositions.clone() : null, mTileMode); |
| } else { // TYPE_COLOR_START_AND_COLOR_END |
| copy = new LinearGradient(mX0, mY0, mX1, mY1, mColor0, mColor1, mTileMode); |
| } |
| copyLocalMatrix(copy); |
| return copy; |
| } |
| |
| private native long nativeCreate1(long matrix, float x0, float y0, float x1, float y1, |
| int colors[], float positions[], int tileMode); |
| private native long nativeCreate2(long matrix, float x0, float y0, float x1, float y1, |
| int color0, int color1, int tileMode); |
| } |