1.Canvas类

public class Canvas {    public static final int ALL_SAVE_FLAG = 31;    /** @deprecated */    @Deprecated    public static final int CLIP_SAVE_FLAG = 2;    /** @deprecated */    @Deprecated    public static final int CLIP_TO_LAYER_SAVE_FLAG = 16;    /** @deprecated */    @Deprecated    public static final int FULL_COLOR_LAYER_SAVE_FLAG = 8;    /** @deprecated */    @Deprecated    public static final int HAS_ALPHA_LAYER_SAVE_FLAG = 4;    /** @deprecated */    @Deprecated    public static final int MATRIX_SAVE_FLAG = 1;    public Canvas()     public Canvas(Bitmap bitmap) ;    public boolean isHardwareAccelerated() ;    public void setBitmap(Bitmap bitmap) ;    public boolean isOpaque() ;    public int getWidth() ;    public int getHeight();    public int getDensity();    public void setDensity(int density) ;    public int getMaximumBitmapWidth() ;    public int getMaximumBitmapHeight() ;    public int save() ;    /** @deprecated */    @Deprecated    public int save(int saveFlags) ;    /** @deprecated */    @Deprecated    public int saveLayer(RectF bounds, Paint paint, int saveFlags) ;    public int saveLayer(RectF bounds, Paint paint) ;    /** @deprecated */    @Deprecated    public int saveLayer(float left, float top, float right, float bottom, Paint paint, int saveFlags);    public int saveLayer(float left, float top, float right, float bottom, Paint paint) ;    /** @deprecated */    @Deprecated    public int saveLayerAlpha(RectF bounds, int alpha, int saveFlags) ;    public int saveLayerAlpha(RectF bounds, int alpha) ;    /** @deprecated */    @Deprecated    public int saveLayerAlpha(float left, float top, float right, float bottom, int alpha, int saveFlags);    public int saveLayerAlpha(float left, float top, float right, float bottom, int alpha);    public void restore() ;    public int getSaveCount() ;    public void restoreToCount(int saveCount);    public void translate(float dx, float dy);    public void scale(float sx, float sy);    public final void scale(float sx, float sy, float px, float py);    public void rotate(float degrees) ;    public final void rotate(float degrees, float px, float py);    public void skew(float sx, float sy) ;    public void concat(Matrix matrix) ;        public void setMatrix(Matrix matrix) ;    /** @deprecated */    @Deprecated    public void getMatrix(Matrix ctm) ;    /** @deprecated */    @Deprecated    public final Matrix getMatrix() ;    /** @deprecated */    @Deprecated    public boolean clipRect(RectF rect, Op op);    /** @deprecated */    @Deprecated    public boolean clipRect(Rect rect, Op op) ;    public boolean clipRect(RectF rect) ;    public boolean clipOutRect(RectF rect);    public boolean clipRect(Rect rect);    public boolean clipOutRect(Rect rect) ;    /** @deprecated */    @Deprecated    public boolean clipRect(float left, float top, float right, float bottom, Op op) ;    public boolean clipRect(float left, float top, float right, float bottom);    public boolean clipOutRect(float left, float top, float right, float bottom);    public boolean clipRect(int left, int top, int right, int bottom);    public boolean clipOutRect(int left, int top, int right, int bottom);    /** @deprecated */    @Deprecated    public boolean clipPath(Path path, Op op);    public boolean clipPath(Path path);    public boolean clipOutPath(Path path) ;    public DrawFilter getDrawFilter();    public void setDrawFilter(DrawFilter filter) ;    public boolean quickReject(RectF rect, Canvas.EdgeType type);    public boolean quickReject(Path path, Canvas.EdgeType type) ;    public boolean quickReject(float left, float top, float right, float bottom, Canvas.EdgeType type);    public boolean getClipBounds(Rect bounds) ;    public final Rect getClipBounds() ;    public void drawPicture(Picture picture) ;    public void drawPicture(Picture picture, RectF dst);    public void drawPicture(Picture picture, Rect dst) ;        /***    oval :      圆弧的外轮廓矩形区域。    startAngle: 圆弧起始角度，单位为度。    sweepAngle: 圆弧扫过的角度，顺时针方向，单位为度    useCenter: 如果为True时，在绘制圆弧时将圆心包括在内，通常用来绘制扇形。如果为false会绘制切弦 看图吧    paint: 绘制圆弧的画板属性，如颜色，是否填充等。**/    public void drawArc(RectF oval, float startAngle, float sweepAngle, boolean useCenter, Paint paint);    public void drawArc(float left, float top, float right, float bottom, float startAngle, float sweepAngle, boolean useCenter, Paint paint) ;            /**  **/    public void drawARGB(int a, int r, int g, int b) ;    public void drawBitmap(Bitmap bitmap, float left, float top, Paint paint) ;    public void drawBitmap(Bitmap bitmap, Rect src, RectF dst, Paint paint);    public void drawBitmap(Bitmap bitmap, Rect src, Rect dst, Paint paint);      @Deprecated    public void drawBitmap(int[] colors, int offset, int stride, float x, float y, int width, int height, boolean hasAlpha, Paint paint) ;    @Deprecated    public void drawBitmap(int[] colors, int offset, int stride, int x, int y, int width, int height, boolean hasAlpha, Paint paint);    public void drawBitmap(Bitmap bitmap, Matrix matrix, Paint paint);    public void drawBitmapMesh(Bitmap bitmap, int meshWidth, int meshHeight, float[] verts, int vertOffset, int[] colors, int colorOffset, Paint paint);        /*** 绘制圆形，圆心坐标cx,cy,半径 radius，paint */    public void drawCircle(float cx, float cy, float radius, Paint paint) ;    /*** 绘制椭圆 */    public void drawOval(RectF oval, Paint paint);    public void drawOval(float left, float top, float right, float bottom, Paint paint);        public void drawColor(int color) ;    public void drawColor(int color, Mode mode) ;    /*****  绘制线段:pos 的数量需要是4个倍数 ******/    public void drawLine(float startX, float startY, float stopX, float stopY, Paint paint) ;    public void drawLines(float[] pts, int offset, int count, Paint paint) ;    public void drawLines(float[] pts, Paint paint) ;        public void drawPaint(Paint paint);    public void drawPath(Path path, Paint paint);    public void drawPoint(float x, float y, Paint paint);    public void drawPoints(float[] pts, int offset, int count, Paint paint) ;    public void drawPoints(float[] pts, Paint paint) ;    @Deprecated    public void drawPosText(char[] text, int index, int count, float[] pos, Paint paint);    @Deprecated    public void drawPosText(String text, float[] pos, Paint paint);    /*** 绘制矩形 */    public void drawRect(RectF rect, Paint paint) ;    public void drawRect(Rect r, Paint paint);    public void drawRect(float left, float top, float right, float bottom, Paint paint);                public void drawRGB(int r, int g, int b);    /******** 绘制圆角矩形，REctF,x轴上的圆角半径，y轴上圆角半径，panint *******/    public void drawRoundRect(RectF rect, float rx, float ry, Paint paint);    public void drawRoundRect(float left, float top, float right, float bottom, float rx, float ry, Paint paint);        /*** 绘制text文字，从text的start到end，绘制中心点在(x,y)，*/    public void drawText(String text, int start, int end, float x, float y, Paint paint) ;    public void drawText(CharSequence text, int start, int end, float x, float y, Paint paint);    public void drawText(char[] text, int index, int count, float x, float y, Paint paint);    public void drawText(String text, float x, float y, Paint paint);            /*** 绘制text文字，str ,path,(path是绘制的text的路径，如：path.addArc,文字会随着arc弧形绘制 )**/    public void drawTextOnPath(String text, Path path, float hOffset, float vOffset, Paint paint) ;    public void drawTextOnPath(char[] text, int index, int count, Path path, float hOffset, float vOffset, Paint paint) ;            public void drawTextRun(char[] text, int index, int count, int contextIndex, int contextCount, float x, float y, boolean isRtl, Paint paint);    public void drawTextRun(CharSequence text, int start, int end, int contextStart, int contextEnd, float x, float y, boolean isRtl, Paint paint);            public void drawVertices(Canvas.VertexMode mode, int vertexCount, float[] verts, int vertOffset, float[] texs, int texOffset, int[] colors, int colorOffset, short[] indices, int indexOffset, int indexCount, Paint paint) ;    public static enum VertexMode {        TRIANGLES,        TRIANGLE_FAN,        TRIANGLE_STRIP;        private VertexMode() {        }    }    public static enum EdgeType {        AA,        BW;        private EdgeType() {        }    }}

2.Paint类

 

public class Paint {    public static final int ANTI_ALIAS_FLAG = 1;    public static final int DEV_KERN_TEXT_FLAG = 256;    public static final int DITHER_FLAG = 4;    public static final int EMBEDDED_BITMAP_TEXT_FLAG = 1024;    public static final int FAKE_BOLD_TEXT_FLAG = 32;    public static final int FILTER_BITMAP_FLAG = 2;    public static final int HINTING_OFF = 0;    public static final int HINTING_ON = 1;    public static final int LINEAR_TEXT_FLAG = 64;    public static final int STRIKE_THRU_TEXT_FLAG = 16;    public static final int SUBPIXEL_TEXT_FLAG = 128;    public static final int UNDERLINE_TEXT_FLAG = 8;    public Paint();    public Paint(int flags);    public Paint(Paint paint);    public void reset();    public void set(Paint src);    public int getFlags() ;    public void setFlags(int flags) ;    public int getHinting();    public void setHinting(int mode);    public final boolean isAntiAlias();    public void setAntiAlias(boolean aa);    public final boolean isDither() ;    public void setDither(boolean dither);    public final boolean isLinearText() ;    public void setLinearText(boolean linearText);    public final boolean isSubpixelText();    public void setSubpixelText(boolean subpixelText);    public final boolean isUnderlineText();    public void setUnderlineText(boolean underlineText);    public final boolean isStrikeThruText();    public void setStrikeThruText(boolean strikeThruText);    public final boolean isFakeBoldText();    public void setFakeBoldText(boolean fakeBoldText);    public final boolean isFilterBitmap() ;    public void setFilterBitmap(boolean filter);    public Paint.Style getStyle() ;    public void setStyle(Paint.Style style);    public int getColor();    public void setColor(int color) ;    public int getAlpha() ;    public void setAlpha(int a);    public void setARGB(int a, int r, int g, int b) ;    public float getStrokeWidth();    public void setStrokeWidth(float width);    public float getStrokeMiter() ;    public void setStrokeMiter(float miter);    public Paint.Cap getStrokeCap();    public void setStrokeCap(Paint.Cap cap);    public Paint.Join getStrokeJoin() ;    public void setStrokeJoin(Paint.Join join);    public boolean getFillPath(Path src, Path dst) ;    public Shader getShader() ;    public Shader setShader(Shader shader) ;    public ColorFilter getColorFilter() ;    public ColorFilter setColorFilter(ColorFilter filter);    public Xfermode getXfermode() ;    public Xfermode setXfermode(Xfermode xfermode);    public PathEffect getPathEffect() ;    public PathEffect setPathEffect(PathEffect effect);    public MaskFilter getMaskFilter();    public MaskFilter setMaskFilter(MaskFilter maskfilter);    public Typeface getTypeface() ;    public Typeface setTypeface(Typeface typeface) ;    public void setShadowLayer(float radius, float dx, float dy, int shadowColor);    public void clearShadowLayer();    public Paint.Align getTextAlign();    public void setTextAlign(Paint.Align align);    public Locale getTextLocale() ;    public LocaleList getTextLocales() ;    public void setTextLocale(Locale locale);    public void setTextLocales(LocaleList locales);    public boolean isElegantTextHeight() ;    public void setElegantTextHeight(boolean elegant) ;    public float getTextSize();    public void setTextSize(float textSize);    public float getTextScaleX();    public void setTextScaleX(float scaleX);    public float getTextSkewX() ;    public void setTextSkewX(float skewX) ;    public float getLetterSpacing();    public void setLetterSpacing(float letterSpacing) ;    public String getFontFeatureSettings();    public void setFontFeatureSettings(String settings);    public String getFontVariationSettings() ;    public boolean setFontVariationSettings(String fontVariationSettings) ;    public float ascent() ;    public float descent();    public float getFontMetrics(Paint.FontMetrics metrics);    public Paint.FontMetrics getFontMetrics();    public int getFontMetricsInt(Paint.FontMetricsInt fmi);    public Paint.FontMetricsInt getFontMetricsInt();    public float getFontSpacing();    public float measureText(char[] text, int index, int count);    public float measureText(String text, int start, int end);    public float measureText(String text) ;    public float measureText(CharSequence text, int start, int end);    public int breakText(char[] text, int index, int count, float maxWidth, float[] measuredWidth);    public int breakText(CharSequence text, int start, int end, boolean measureForwards, float maxWidth, float[] measuredWidth);    public int breakText(String text, boolean measureForwards, float maxWidth, float[] measuredWidth) ;    public int getTextWidths(char[] text, int index, int count, float[] widths);    public int getTextWidths(CharSequence text, int start, int end, float[] widths);    public int getTextWidths(String text, int start, int end, float[] widths);    public int getTextWidths(String text, float[] widths);    public void getTextPath(char[] text, int index, int count, float x, float y, Path path);    public void getTextPath(String text, int start, int end, float x, float y, Path path) ;    public void getTextBounds(String text, int start, int end, Rect bounds) ;    public void getTextBounds(char[] text, int index, int count, Rect bounds);    public boolean hasGlyph(String string);    public float getRunAdvance(char[] text, int start, int end, int contextStart, int contextEnd, boolean isRtl, int offset);    public float getRunAdvance(CharSequence text, int start, int end, int contextStart, int contextEnd, boolean isRtl, int offset);    public int getOffsetForAdvance(char[] text, int start, int end, int contextStart, int contextEnd, boolean isRtl, float advance);    public int getOffsetForAdvance(CharSequence text, int start, int end, int contextStart, int contextEnd, boolean isRtl, float advance) ;    public static class FontMetricsInt {        public int ascent;        public int bottom;        public int descent;        public int leading;        public int top;        public FontMetricsInt() {            throw new RuntimeException("Stub!");        }        public String toString() {            throw new RuntimeException("Stub!");        }    }    public static class FontMetrics {        public float ascent;        public float bottom;        public float descent;        public float leading;        public float top;        public FontMetrics() {            throw new RuntimeException("Stub!");        }    }    public static enum Align {        CENTER,        LEFT,        RIGHT;        private Align() {        }    }    public static enum Join {        BEVEL,        MITER,        ROUND;        private Join() {        }    }    public static enum Cap {        BUTT,        ROUND,        SQUARE;        private Cap() {        }    }    public static enum Style {        FILL,        FILL_AND_STROKE,        STROKE;        private Style() {        }    }}

 

 简单几何图形绘制

 

3.drawRect矩形绘制

 

/*** 绘制矩形 */    public void drawRect(RectF rect, Paint paint) ;    public void drawRect(Rect r, Paint paint);    public void drawRect(float left, float top, float right, float bottom, Paint paint);   /*** 绘制圆角矩形，REctF,x轴上的圆角半径，y轴上圆角半径，panint ****/    public void drawRoundRect(RectF rect, float rx, float ry, Paint paint);    public void drawRoundRect(float left, float top, float right, float bottom, float rx, float ry, Paint paint);

 

4.drawLine绘制线段

/*****  绘制线段:pts 的数量需要是4的倍数 ******/public void drawLine(float startX, float startY, float stopX, float stopY, Paint    paint) ;public void drawLines(float[] pts, int offset, int count, Paint paint) ;public void drawLines(float[] pts, Paint paint) ;

Paint rectPaint = new Paint();        rectPaint.setAntiAlias(true);        rectPaint.setColor(Color.GRAY);        rectPaint.setStyle(Paint.Style.STROKE);        rectPaint.setStrokeWidth(5);        rectPaint.setAntiAlias(true);        rectPaint.setStyle(Paint.Style.FILL);        rectPaint.setColor(0x88FF0000);        /***** pos 的数量需要是4个倍数*/       float []pos=new float[]{10,10,10,100,100,100,100,240};        /***** pos 每4个一组，4个float代表2个点坐标，然后连接成线*/       // canvas.drawLines(pos,rectPaint);        /**** pos，从点pos[2]到pos[5]*/        canvas.drawLines(pos,rectPaint);

 5.绘制圆或椭圆

/*** 绘制圆形，圆心坐标cx,cy,半径 radius，paint */    public void drawCircle(float cx, float cy, float radius, Paint paint) ;    /*** 绘制椭圆 */    public void drawOval(RectF oval, Paint paint);    public void drawOval(float left, float top, float right, float bottom, Paint paint);

6.绘制弧形

/***    oval :      圆弧的外轮廓矩形区域。    startAngle: 圆弧起始角度，单位为度。    sweepAngle: 圆弧扫过的角度，顺时针方向，单位为度    useCenter:  如果为True时，在绘制圆弧时将圆心包括在内，通常用来绘制扇形。如果为false会绘制切弦 看图吧    paint:     圆弧的画板属性，如颜色，是否填充等。**/    public void drawArc(RectF oval, float startAngle, float sweepAngle, boolean useCenter, Paint paint);    public void drawArc(float left, float top, float right, float bottom, float startAngle, float sweepAngle, boolean useCenter, Paint paint) ;

7.drawPath 绘制图形

public void drawPath(Path path, Paint paint);

 

Paint pathPaint = new Paint();        pathPaint.setARGB(70, 238, 18, 137);        pathPaint.setStyle(Paint.Style.FILL);        pathPaint.setAntiAlias(true);        pathPaint.setStrokeWidth(5);        pathPaint.setColor(Color.CYAN);        pathPaint.setStyle(Paint.Style.FILL);        Path path = new Path();        /*** 这个是上图的第三个 */        path.moveTo(100,100);        path.lineTo(50,300);        path.lineTo(300,100);        path.lineTo(350,300);        canvas.drawPath(path,pathPaint);

按上图drawpath绘制图形，有moveTo()作为起始点，lineTo连接到各个顶点。第四个图的梯形是moveTo(A)，LineTo(B),LineTo(c) 然后再次moveTo(D),LineTo(B),LineTo(C)的

 8.绘制drawText 

/*** 绘制text文字，从text的start到end，绘制起点在(x,y)，*/    public void drawText(String text, int start, int end, float x, float y, Paint paint) ;    public void drawText(CharSequence text, int start, int end, float x, float y, Paint paint);     /*** 绘制text文字，从text的index，绘制count个字数，绘制起点在(x,y)，*/    public void drawText(char[] text, int index, int count, float x, float y, Paint paint);    public void drawText(String text, float x, float y, Paint paint);

 

 drawTextOnPath方法：

 

/*** 绘制text文字，str ,path,(path是绘制的text的路径，如：path.addArc,文字会随着arc弧形绘制 )**/    public void drawTextOnPath(String text, Path path, float hOffset, float vOffset, Paint paint) ;    public void drawTextOnPath(char[] text, int index, int count, Path path, float hOffset, float vOffset, Paint paint) ;

 

 

 

Path path=new Path(); path.addRoundRect(100,100,300,300,10,10, Path.Direction.CW);  /*** path.addRoundRect(100,100,300,300,10,10, Path.Direction.CWW); */ canvas.drawTextOnPath("这里是drawTextOnPath方法",  path,  20, 20, rectPaint);

Paint rectPaint = new Paint();        rectPaint.setAntiAlias(true);        rectPaint.setColor(Color.RED);        rectPaint.setStrokeWidth(5);        rectPaint.setAntiAlias(true);        rectPaint.setStyle(Paint.Style.STROKE);        rectPaint.setColor(0x88FF0000);        rectPaint.setTextSize(40);

 

CW和CWW的区别：顺时针和逆时针

 

 

path.addArc()中没有Direction属性，绘制图形大致为下：

 drawTextRun方法

 

public void drawTextRun(char[] text, int index, int count, int contextIndex, int contextCount, float x, float y, boolean isRtl, Paint paint); public void drawTextRun(CharSequence text, int start, int end, int contextStart, int contextEnd, float x, float y, boolean isRtl, Paint paint);

 

上面的CAN SHU 呢index开始下标，count绘制的数目，contextIndex和index一样（否则就异常退出了） contextCount>=count 。该方法要求api 23呢，isRtl改变了绘制的顺序，

false为正序，true为倒叙了。

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {            canvas.drawTextRun("眼前风景不足停,不远之处是梦想".toCharArray(), 0, 7, 0, 7, 200, 500, false, rectPaint);            canvas.drawTextRun("眼前风景不足停,不远之处是梦想".toCharArray(), 0, 7, 0, 9, 200, 600, true, rectPaint);            canvas.drawTextRun("眼前风景不足停,不远之处是梦想".toCharArray(), 0, 4, 0, 9, 200, 700, false, rectPaint);            canvas.drawTextRun("眼前风景不足停,不远之处是梦想".toCharArray(), 0, 4, 0, 9, 200, 800, true, rectPaint);        }

如图：