渲染模式：
tileX tileY：The tiling mode for x/y to draw the bitmap in. 在位圖上 X/Y 方向 瓦工/花磚/瓷磚 模式
CLAMP ：如果渲染器超出原始邊界范圍，會復制范圍內【邊緣】染色
REPEA ：橫向和縱向的【重復】渲染器圖片，平鋪
MIRROR：橫向和縱向的重復渲染器圖片，這個和REPEAT 重復方式不一樣，他是以【鏡像】方式平鋪
渲染模式示例代碼
public
class
LinearGradientView
extends
View {
private Paint mPaint = null;
private Shader mLinearGradient11 = null;
private Shader mLinearGradient12 = null;
private Shader mLinearGradient13 = null;
private Shader mLinearGradient21 = null;
private Shader mLinearGradient22 = null;
private Shader mLinearGradient23 = null;
private Shader mLinearGradient31 = null;
private Shader mLinearGradient32 = null;
private Shader mLinearGradient33 = null;
public LinearGradientView(Context context) {
super(context);
// 第一第二個參數表示漸變起點，可以設置在對角等任意位置；第三第四個參數表示漸變終點；第五個參數表示漸變顏色；
// 第六個參數可以為空，表示坐標值為0-1 new float[] {0.25f, 0.5f, 0.75f, 1 } 如果為空，顏色均勻分布，沿梯度線。
mLinearGradient11 = new LinearGradient(0, 0, 0, 200, new int[] { Color.RED, Color.GREEN, Color.BLUE, Color.BLACK }, null, TileMode.CLAMP);
mLinearGradient12 = new LinearGradient(0, 0, 0, 300, new int[] { Color.RED, Color.GREEN, Color.BLUE, Color.BLACK }, new float[] { 0, 0.1f, 0.5f, 0.5f }, TileMode.CLAMP);
mLinearGradient13 = new LinearGradient(0, 0, 0, 400, new int[] { Color.RED, Color.GREEN, Color.BLUE }, null, TileMode.CLAMP);
mLinearGradient21 = new LinearGradient(0, 320, 0, 320 + 200, new int[] { Color.RED, Color.GREEN, Color.BLUE, Color.BLACK }, null, TileMode.MIRROR);
mLinearGradient22 = new LinearGradient(0, 320, 0, 320 + 100, new int[] { Color.RED, Color.GREEN, Color.BLUE }, null, TileMode.MIRROR);
mLinearGradient23 = new LinearGradient(0, 320, 0, 320 + 100, new int[] { Color.RED, Color.GREEN, Color.BLUE }, new float[] { 0, 0.1f, 0.5f }, TileMode.MIRROR);
mLinearGradient31 = new LinearGradient(0, 640, 0, 640 + 200, new int[] { Color.RED, Color.GREEN, Color.BLUE, Color.BLACK }, null, TileMode.REPEAT);
mLinearGradient32 = new LinearGradient(0, 640, 0, 640 + 100, new int[] { Color.RED, Color.GREEN, Color.BLUE }, null, TileMode.REPEAT);
mLinearGradient33 = new LinearGradient(0, 640, 0, 640 + 100, new int[] { Color.RED, Color.GREEN, Color.BLUE }, new float[] { 0, 0.1f, 0.5f }, TileMode.REPEAT);
mPaint = new Paint();
}
@Override
protected void onDraw(Canvas canvas) {
//重復最后一個像素
mPaint.setStrokeWidth(2);
mPaint.setShader(mLinearGradient11);
canvas.drawRect(0, 0, 200, 300, mPaint);//200-300之間全部是最后的黑色
mPaint.setShader(mLinearGradient12);
canvas.drawRect(210, 0, 410, 300, mPaint);//0.5之后全部是黑色了
mPaint.setShader(mLinearGradient13);
canvas.drawRect(420, 0, 620, 300, mPaint); // LinearGradient的高度小於要繪制的矩形的高度時才會有重復、鏡像等效果
canvas.drawLine(0, 310, 720, 310, mPaint);
//鏡像效果
mPaint.setShader(mLinearGradient21);
canvas.drawRect(0, 320, 200, 620, mPaint);
mPaint.setShader(mLinearGradient22);
canvas.drawRect(210, 320, 410, 620, mPaint);
mPaint.setShader(mLinearGradient23);
canvas.drawRect(420, 320, 620, 620, mPaint);
canvas.drawLine(0, 630, 720, 630, mPaint);
//重復效果
mPaint.setShader(mLinearGradient31);
canvas.drawRect(0, 640, 200, 940, mPaint);
mPaint.setShader(mLinearGradient32);
canvas.drawRect(210, 640, 410, 940, mPaint);
mPaint.setShader(mLinearGradient33);
canvas.drawRect(420, 640, 620, 940, mPaint);
}
}
渲染器示例代碼
public
class
MyShaderView
extends
View {
// Shader渲染器，專門用來渲染圖像以及一些幾何圖形
private BitmapShader bitmapShader; //bitmap渲染器，主要用來渲染圖像
private LinearGradient linearGradient; //線性渲染
private RadialGradient radialGradient; //環形渲染
private SweepGradient sweepGradient; //掃描漸變，圍繞一個中心點掃描漸變就像電影里那種雷達掃描，用來梯度渲染
private ComposeShader composeShader; //混合渲染器，可以和其他幾個子類組合起來使用
private Bitmap bitmap;
/**Bitmap的寬高*/
private int width, height;
private Paint paint;
/**漸變顏色數組*/
private final int[] colors = { Color.RED, Color.GREEN, Color.BLUE, Color.YELLOW };
/**用來指定顏色數組的相對位置，若為null則均勻分布*/
private final float[] positions = null;
public MyShaderView(Context context) {
super(context);
bitmap = ((BitmapDrawable) getResources().getDrawable(R.drawable.icon)).getBitmap();
width = bitmap.getWidth();
height = bitmap.getHeight();
paint = new Paint();
}
@SuppressLint("DrawAllocation")
@Override
protected void onDraw(Canvas canvas) {
super.onDraw(canvas);
canvas.drawColor(Color.WHITE); //背景色
//將Bitmap截取為圓形、圓角矩形
canvas.drawBitmap(bitmap, 0, 0, paint);//原圖
bitmapShader = new BitmapShader(bitmap, TileMode.MIRROR, TileMode.MIRROR);
paint.setShader(bitmapShader);
canvas.drawOval(new RectF(width, 0, width * 2, height), paint);//圓形渲染圖
canvas.drawRoundRect(width * 2, 0, width * 3, height, 30, 30, paint);//矩形渲染圖
//繪制線性漸變的矩形
linearGradient = new LinearGradient(0, 200, 400, 400, colors, positions, TileMode.REPEAT);// 漸變起 初點/終點坐標 x/y 位置；
paint.setShader(linearGradient);
canvas.drawRect(0, 200, 400, 400, paint);//渲染范圍最好和圖形大小一致
//繪制環形漸變的圓和矩形
radialGradient = new RadialGradient(100, 500, 100, colors, positions, TileMode.REPEAT);// 中心坐標、半徑
paint.setShader(radialGradient);
canvas.drawCircle(100, 500, 100, paint);
canvas.drawRect(200, 400, 300, 600, paint);
radialGradient = new RadialGradient(300, 500, 100, colors, positions, TileMode.MIRROR);
paint.setShader(radialGradient);
canvas.drawCircle(400, 500, 100, paint);
canvas.drawRect(500, 400, 600, 600, paint);
//繪制梯形漸變的矩形
sweepGradient = new SweepGradient(300, 710, colors, positions);//中心坐標
paint.setShader(sweepGradient);
canvas.drawRect(0, 610, 600, 810, paint);
//繪制混合漸變(線性與環形混合)的矩形
linearGradient = new LinearGradient(0, 820, 300, 1120, colors, positions, TileMode.REPEAT);
composeShader = new ComposeShader(linearGradient, bitmapShader, PorterDuff.Mode.SRC_OVER);
paint.setShader(composeShader);
canvas.drawRect(0, 820, 600, 1120, paint);
}
}