//坐标轴的初始化 -(void)axesInit { // Setup plot space: 设置一屏内可显示的x,y量度范围 CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *)[xyGraph defaultPlotSpace]; plotSpace.delegate = self; plotSpace.allowsUserInteraction = YES;//允许拖动 //设置移动时的停止动画 这些参数保持默认即可 变化不大 plotSpace.momentumAnimationCurve = CPTAnimationCurveCubicIn; plotSpace.bounceAnimationCurve = CPTAnimationCurveBackIn; plotSpace.momentumAcceleration = 20000.0; //设置x,y在视图显示中大小，也就是点的个数，通过这样设置可以达到放大缩小的效果，来达到我们想要的合理视图显示 plotSpace.xRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(18.0) length:CPTDecimalFromFloat(22.0)]; plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(32.0) length:CPTDecimalFromFloat(10.5)]; //设置x、y轴的滚动范围，如果不设置，默认是无线长的 plotSpace.globalXRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(-1.0) length:CPTDecimalFromFloat(25.0)]; plotSpace.globalYRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(32.0) length:CPTDecimalFromFloat(10.5)]; // Axes: 设置x,y轴属性，如原点，量度间隔，标签，刻度，颜色等 CPTXYAxisSet *axisSet = (CPTXYAxisSet *)xyGraph.axisSet; CPTMutableLineStyle *lineStyle = [CPTMutableLineStyle lineStyle]; lineStyle.miterLimit = 1.0f; lineStyle.lineWidth = 1.0f; lineStyle.lineColor = [CPTColor whiteColor]; [plotSpace setAllowsMomentumX:YES]; CPTXYAxis *x = axisSet.xAxis; x.orthogonalCoordinateDecimal = CPTDecimalFromString(@"33");// x轴的原点位置，其实这里是y坐标的值，也就是说x轴的原点在y轴的1位置 x.majorIntervalLength = CPTDecimalFromString(@"1.0"); // x轴主刻度：显示数字标签的量度间隔 x.minorTicksPerInterval = 4; // x轴细分刻度：每一个主刻度范围内显示细分刻度的个数 x.minorTickLineStyle = lineStyle; lineStyle.lineColor = [CPTColor lightGrayColor]; x.majorGridLineStyle = lineStyle;//这里设置x轴中主刻度的栅格，平行于y轴 // 需要排除的不显示数字的主刻度 NSArray *exclusionRanges = [NSArray arrayWithObjects: [self CPTPlotRangeFromFloat:0.99 length:0.02], [self CPTPlotRangeFromFloat:2.99 length:0.02], nil nil]; x.labelExclusionRanges = exclusionRanges; CPTXYAxis *y = axisSet.yAxis; y.orthogonalCoordinateDecimal = CPTDecimalFromString(@"18");//y轴的原点位置，其实这里是x坐标的值，也就是说y轴的原点在x轴的0位置 //固定y轴，也就是在你水平移动时，y轴是固定在左/右边不动的，以此类推x轴 y.axisConstraints = [CPTConstraints constraintWithLowerOffset:20];//这里是固定y坐标轴在最右边（距离可视右边界有20个像素距离，一遍显示标签） y.majorIntervalLength = CPTDecimalFromString(@"0.5"); y.minorTicksPerInterval = 4; y.minorTickLineStyle = lineStyle; y.tickDirection = CPTSignNegative;//标签的方向，对于y轴来说：CPTSignPositive标签在y轴的右边，CPTSignNegative：在y轴的左侧 lineStyle.lineColor = [CPTColor lightGrayColor]; y.majorGridLineStyle = lineStyle;//设置栅格线，平行于x轴 如果 labelingPolicy 设置为 CPTAxisLabelingPolicyNone ， majorGridLineStyle 将不起作用 // y.labelingPolicy = CPTAxisLabelingPolicyNone; NSArray *exclusionRangesY = [NSArray arrayWithObjects: [self CPTPlotRangeFromFloat:1.99 length:0.2], [self CPTPlotRangeFromFloat:2.99 length:0.2], nil nil]; y.labelExclusionRanges = exclusionRangesY; y.delegate = self; }
/** @brief Creates and returns a new CPTConstraints instance initialized with a fixed offset from the lower bound. * @param newOffset The offset. * @return A new CPTConstraints instance initialized with the given offset. * @sfx :该函数主要是实现固定坐标轴在距离最小端newoffset的地方，我个人对大端小端的理解：对y轴来说，最大端（或者说最高处）也就是我们坐标系bounce的右边界 * 最小端（或者说最低处）就是坐标系视图boundce的左边界，这样x轴也就同样可以理解了，相应的就是上、下边界 **/ +(CPTConstraints *)constraintWithLowerOffset:(CGFloat)newOffset { return [[(_CPTConstraintsFixed *)[_CPTConstraintsFixed alloc] initWithLowerOffset : newOffset] autorelease]; } <pre name="code" class="objc">/** @brief Creates and returns a new CPTConstraints instance initialized with a fixed offset from the upper bound. * @param newOffset The offset. * @return A new CPTConstraints instance initialized with the given offset. * @sfx :该函数主要是实现固定坐标轴在距离最高端newoffset的地方，我个人对大端小端的理解：对y轴来说，最大端（或者说最高处）也就是我们坐标系bounce的右边界 * 最小端（或者说最低处）就是坐标系视图boundce的左边界，这样x轴也就同样可以理解了，相应的就是上、下边界 **/ +(CPTConstraints *)constraintWithUpperOffset:(CGFloat)newOffset{ return [[(_CPTConstraintsFixed *)[_CPTConstraintsFixed alloc] initWithUpperOffset : newOffset] autorelease]; } /** @brief Creates and returns a new CPTConstraints instance initialized with a proportional offset relative to the bounds. * * For example, an offset of @num{0.0} will return a position equal to the lower bound, @num{1.0} will return the upper bound, * and @num{0.5} will return a point midway between the two bounds. * * @param newOffset The offset. * @sfx ： 这个类方法实现的是按一定比例值来固定坐标轴，比如我们固定y轴，如果newoffset = 1.0，就相当于把y轴固定在右边界，如果newoffset = 0.0 就是左边界，如果等于0.5就是中间 newoffset取值范围：0 --- 1.0 * @return A new CPTConstraints instance initialized with the given offset. **/ +(CPTConstraints *)constraintWithRelativeOffset:(CGFloat)newOffset{ return [[(_CPTConstraintsRelative *)[_CPTConstraintsRelative alloc] initWithRelativeOffset : newOffset] autorelease]; }