1 BitmapShader
/**
* 初始化 画笔
*/
private void initPaint () {
mPaint.setStyle(Paint.Style.FILL);
mPaint.setColor(Color.RED);
mPaint.setStrokeWidth(10);
mBitmap= BitmapFactory.decodeResource(mContext.getResources(), R.drawable.bg_bee_animation03);
// 第一个参数 是指定图片
// 第二个参数 是x轴的 模式设置
// 第三个参数 则是y轴的 模式设置
// 模式一共有三种
// 1 Shader.TileMode.CLAMP 延某一个轴的最后一个像素点拉伸
// 2 Shader.TileMode.REPEAT 重复
// 3 Shader.TileMode.MIRROR 镜像重复
BitmapShader bitmapShader = new BitmapShader(mBitmap, Shader.TileMode.CLAMP, Shader.TileMode.CLAMP);
mPaint.setShader(bitmapShader);
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
mViewWidth = w;
mViewHeight = h;
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawRect(0,0,mViewWidth,mViewHeight,mPaint);
}
效果
图片.png
BitmapShader bitmapShader = new BitmapShader(mBitmap, Shader.TileMode.CLAMP, Shader.TileMode.REPEAT);
y轴重复
BitmapShader bitmapShader = new BitmapShader(mBitmap, Shader.TileMode.REPEAT, Shader.TileMode.REPEAT);
全部重复
图片.png
BitmapShader bitmapShader = new BitmapShader(mBitmap, Shader.TileMode.MIRROR, Shader.TileMode.REPEAT);
x轴镜像 y轴重复
图片.png
在
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
}
这个函数中我们看看到
canvas 执行的这样drawRect的函数是不是可以理解为 那边shadebitmap什么的 是绘制的一个背景图
LinearGradient
/**
* 初始化 画笔
*/
private void initPaint () {
mPaint.setStyle(Paint.Style.FILL);
mPaint.setColor(Color.RED);
mPaint.setStrokeWidth(10);
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
mViewWidth = w;
mViewHeight = h;
}
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
// LinearGradient最简单的一个构造方法，
// 参数一和参数二 表示渐变的起点坐标而
// 参数三和参数四 则表示渐变的终点坐标，
// 这两点都是相对于屏幕坐标系而言的，
// 参数五和参数六表示起点的颜色和终点的颜色
LinearGradient linearGradient = new LinearGradient(0, 0, mViewWidth, mViewHeight, Color.BLACK, Color.RED, Shader.TileMode.REPEAT);
mPaint.setShader(linearGradient);
canvas.drawRect(0,0,mViewWidth,mViewHeight,mPaint);
}
效果图
图片.png
修改模式
new LinearGradient(0, 0, mViewWidth/2, mViewHeight/2, Color.BLACK, Color.RED, Shader.TileMode.CLAMP);
为CLAMP
效果
图片.png
new LinearGradient(0, 0, mViewWidth/2, mViewHeight/2, Color.BLACK, Color.RED, Shader.TileMode.REPEAT);
图片.png
new LinearGradient(0, 0, mViewWidth/2, mViewHeight/2, Color.BLACK, Color.RED, Shader.TileMode.MIRROR);
效果图
图片.png
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
//定义所有渐变的颜色
int [] myColor = new int[]{Color.BLUE ,Color.RED, Color.YELLOW, Color.GREEN, Color.CYAN};
//表示的是渐变的相对区域其取值只有0到1
float [] myPositions = new float[]{0,0.2f,0.4f,0.8f,1f};
//myColor和myPositions的个数要一样
LinearGradient linearGradient = new LinearGradient(0, 0, mViewWidth/2, mViewHeight/2,myColor, myPositions, Shader.TileMode.MIRROR);
mPaint.setShader(linearGradient);
canvas.drawRect(0,0,mViewWidth,mViewHeight,mPaint);
}
图片.png
图片倒影效果
/**
* 初始化 画笔
*/
private void initPaint () {
mPaint.setStyle(Paint.Style.FILL);
mPaint.setColor(Color.RED);
mPaint.setStrokeWidth(10);
mBitmap = BitmapFactory.decodeResource(mContext.getResources(), R.drawable.bg_bee_animation03);
// 实例化一个矩阵对象
Matrix matrix = new Matrix();
matrix.setScale(1F, -1F);
// 生成倒影图
mRefBitmap = Bitmap.createBitmap(mBitmap, 0, 0, mBitmap.getWidth(), mBitmap.getHeight(), matrix, true);
}
@Override
protected void onSizeChanged(int w, int h, int oldw, int oldh) {
super.onSizeChanged(w, h, oldw, oldh);
mViewWidth = w;
mViewHeight = h;
}
@SuppressLint("DrawAllocation")
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawColor(Color.BLACK);
int x = mViewWidth/2;
int y = mViewHeight/2;
LinearGradient linearGradient = new LinearGradient(x, y + mBitmap.getHeight(), x, y + mBitmap.getHeight() + mBitmap.getHeight() / 2,
0xAA000000, Color.BLACK, Shader.TileMode.CLAMP);
mPaint.setShader(linearGradient);
canvas.drawBitmap(mBitmap, x, y, null);
canvas.drawBitmap(mRefBitmap, x, y + mBitmap.getHeight(), null);
canvas.drawRect(x, y + mBitmap.getHeight(), x + mRefBitmap.getWidth(), y + mBitmap.getHeight() * 2, mPaint);
}
效果
图片.png
RadialGradient
梯度渐变，也称之为扫描式渐变
