1 /* 2 * Copyright (C) 2007 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package android.graphics; 18 19 public class LinearGradient extends Shader { 20 /** Create a shader that draws a linear gradient along a line. 21 @param x0 The x-coordinate for the start of the gradient line 22 @param y0 The y-coordinate for the start of the gradient line 23 @param x1 The x-coordinate for the end of the gradient line 24 @param y1 The y-coordinate for the end of the gradient line 25 @param colors The colors to be distributed along the gradient line 26 @param positions May be null. The relative positions [0..1] of 27 each corresponding color in the colors array. If this is null, 28 the the colors are distributed evenly along the gradient line. 29 @param tile The Shader tiling mode 30 */ LinearGradient(float x0, float y0, float x1, float y1, int colors[], float positions[], TileMode tile)31 public LinearGradient(float x0, float y0, float x1, float y1, int colors[], float positions[], 32 TileMode tile) { 33 if (colors.length < 2) { 34 throw new IllegalArgumentException("needs >= 2 number of colors"); 35 } 36 if (positions != null && colors.length != positions.length) { 37 throw new IllegalArgumentException("color and position arrays must be of equal length"); 38 } 39 native_instance = nativeCreate1(x0, y0, x1, y1, colors, positions, tile.nativeInt); 40 native_shader = nativePostCreate1(native_instance, x0, y0, x1, y1, colors, positions, 41 tile.nativeInt); 42 } 43 44 /** Create a shader that draws a linear gradient along a line. 45 @param x0 The x-coordinate for the start of the gradient line 46 @param y0 The y-coordinate for the start of the gradient line 47 @param x1 The x-coordinate for the end of the gradient line 48 @param y1 The y-coordinate for the end of the gradient line 49 @param color0 The color at the start of the gradient line. 50 @param color1 The color at the end of the gradient line. 51 @param tile The Shader tiling mode 52 */ LinearGradient(float x0, float y0, float x1, float y1, int color0, int color1, TileMode tile)53 public LinearGradient(float x0, float y0, float x1, float y1, int color0, int color1, 54 TileMode tile) { 55 native_instance = nativeCreate2(x0, y0, x1, y1, color0, color1, tile.nativeInt); 56 native_shader = nativePostCreate2(native_instance, x0, y0, x1, y1, color0, color1, 57 tile.nativeInt); 58 } 59 nativeCreate1(float x0, float y0, float x1, float y1, int colors[], float positions[], int tileMode)60 private native int nativeCreate1(float x0, float y0, float x1, float y1, 61 int colors[], float positions[], int tileMode); nativeCreate2(float x0, float y0, float x1, float y1, int color0, int color1, int tileMode)62 private native int nativeCreate2(float x0, float y0, float x1, float y1, 63 int color0, int color1, int tileMode); nativePostCreate1(int native_shader, float x0, float y0, float x1, float y1, int colors[], float positions[], int tileMode)64 private native int nativePostCreate1(int native_shader, float x0, float y0, float x1, float y1, 65 int colors[], float positions[], int tileMode); nativePostCreate2(int native_shader, float x0, float y0, float x1, float y1, int color0, int color1, int tileMode)66 private native int nativePostCreate2(int native_shader, float x0, float y0, float x1, float y1, 67 int color0, int color1, int tileMode); 68 } 69