Core-Plot：2Y繪圖縮放問題

Question

我們已經使用Core-Plot實現了2Y散點圖 - 輸出結果是用X和Y軸繪製了一張圖表，然後在頂部繪製了一些空白區域，然後繪製了X和Y2軸圖表。

我們希望圖表具有X和Y軸，X軸和Y2軸圖表重疊，以便用戶可以正確查看。

示例代碼是在這裏：

-(void)configureGraph { 
    graph = [[CPTXYGraph alloc] initWithFrame:CGRectMake(0, 0, self.hostView.bounds.size.width, self.hostView.bounds.size.height)]; 
    [graph applyTheme:[CPTTheme themeNamed:kCPTPlainWhiteTheme]]; 
    self.hostView.hostedGraph = graph; 

    [graph setPaddingTop:5.0f]; 
    [graph setPaddingLeft:5.0f]; 
    [graph setPaddingRight:5.0f]; 
    [graph setPaddingBottom:5.0f]; 
    [graph.plotAreaFrame setPaddingTop:5.0f]; 
    [graph.plotAreaFrame setPaddingRight:20.0f]; 
    [graph.plotAreaFrame setPaddingLeft:20.0f]; 
    [graph.plotAreaFrame setPaddingBottom:25.0f]; 
    graph.plotAreaFrame.borderLineStyle = nil; 
} 

-(void)configurePlots { 
    CPTColor *your_color = [CPTColor colorWithComponentRed:126 green:230 blue:255 alpha:0]; 
    int cntSelectedVar = 0; 
    graph = self.hostView.hostedGraph; 
    CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *)graph.defaultPlotSpace; 
    CPTXYPlotSpace *plotSpace2 = (CPTXYPlotSpace *) graph.defaultPlotSpace; 
    plotSpace.allowsUserInteraction = NO; 
    plotSpace2.allowsUserInteraction = NO; 
//  

     // 1 - Get graph and plot space 

     graph.plotAreaFrame.fill = [CPTFill fillWithColor:your_color]; 
     // 2 - Create the three plots 
     CPTScatterPlot *aaplPlot = [[CPTScatterPlot alloc] init]; 
     aaplPlot.dataSource = self; 
     aaplPlot.identifier = variableID ; 
     CPTColor *aaplColor = [self GetRGBForPlotSymbol:cntSelectedVar]; 
     [graph addPlot:aaplPlot toPlotSpace:plotSpace]; 
     CPTMutablePlotRange *xRange = [plotSpace.xRange mutableCopy]; 

     plotSpace.xRange = xRange; 
     CPTMutablePlotRange *yRange = [plotSpace.yRange mutableCopy]; 
     plotSpace.yRange = yRange; 


     // 4 - Create styles and symbols 
     CPTMutableLineStyle *aaplLineStyle = [aaplPlot.dataLineStyle mutableCopy]; 
     aaplLineStyle.lineWidth = 0; 
     aaplLineStyle.lineColor = aaplColor; 
     aaplPlot.dataLineStyle = aaplLineStyle; 
     CPTMutableLineStyle *aaplSymbolLineStyle = [CPTMutableLineStyle lineStyle]; 
     aaplSymbolLineStyle.lineColor = aaplColor; 
     CPTPlotSymbol *aaplSymbol = [CPTPlotSymbol ellipsePlotSymbol]; 
     aaplSymbol.fill = [CPTFill fillWithColor:aaplColor]; 
     aaplSymbol.lineStyle = aaplSymbolLineStyle; 
     aaplSymbol.size = CGSizeMake(3.0f, 3.0f); 
     aaplPlot.plotSymbol = aaplSymbol; 
     cntSelectedVar++; 



     CPTScatterPlot *googPlot= [[CPTScatterPlot alloc] init]; 
     googPlot.dataSource = self; 
     googPlot.identifier = variableID; 
     [self.hostView.hostedGraph addPlot:googPlot]; 
     CPTColor *googColor = [self GetRGBForPlotSymbol:cntSelectedVar]; 

plotSpace2.xRange = plotSpace.xRange; 
    CPTMutablePlotRange *y2Range = [[CPTMutablePlotRange alloc] initWithLocation:CPTDecimalFromDouble(FinalMinValueY2) length:CPTDecimalFromDouble(FinalMaxValueY2)]; 
plotSpace2.yRange = y2Range ; 
     CPTMutableLineStyle *googLineStyle = [googPlot.dataLineStyle mutableCopy]; 
     googLineStyle.lineWidth = 0; 
     googLineStyle.lineColor = googColor; 
     googPlot.dataLineStyle = googLineStyle; 
     CPTMutableLineStyle *googSymbolLineStyle = [CPTMutableLineStyle lineStyle]; 
     googSymbolLineStyle.lineColor = googColor; 
     CPTPlotSymbol *googSymbol = [CPTPlotSymbol ellipsePlotSymbol]; 
     googSymbol.fill = [CPTFill fillWithColor:googColor]; 
     googSymbol.lineStyle = googSymbolLineStyle; 
     googSymbol.size = CGSizeMake(3.0f, 3.0f); 
     googPlot.plotSymbol = googSymbol; 
     [graph addPlot:googPlot toPlotSpace:plotSpace2]; 
     cntSelectedVar++; 


    [plotSpace scaleToFitPlots:[graph allPlots]]; 

    CPTMutableTextStyle *axisTitleStyle = [CPTMutableTextStyle textStyle]; 
    axisTitleStyle.color = [CPTColor blackColor]; 
    axisTitleStyle.fontName = @"Helvetica"; 
    axisTitleStyle.fontSize = 10.0f; 
    CPTMutableLineStyle *axisLineStyle = [CPTMutableLineStyle lineStyle ]; 
    axisLineStyle.lineWidth = 1.0f; 
    axisLineStyle.lineColor = [CPTColor blackColor]; 
    CPTMutableTextStyle *axisTextStyle = [[CPTMutableTextStyle alloc] init]; 
    axisTextStyle.color = [CPTColor blackColor]; 
    axisTextStyle.fontName = @"Helvetica"; 
    axisTextStyle.fontSize = 8.0f; 
    CPTMutableLineStyle *tickLineStyle = [CPTMutableLineStyle lineStyle]; 
    tickLineStyle.lineColor = [CPTColor blackColor]; 
    tickLineStyle.lineWidth = 1.0f; 
    CPTMutableLineStyle *gridLineStyle = [CPTMutableLineStyle lineStyle]; 
    gridLineStyle.lineColor = [CPTColor grayColor]; 
    gridLineStyle.lineWidth = 1.0f; 


    tickLineStyle.lineColor = [CPTColor blackColor]; 
    tickLineStyle.lineWidth = 1.0f; 
    // 2 - Get axis set 
    CPTXYAxisSet *axisSet = (CPTXYAxisSet *) (id)self.hostView.hostedGraph.axisSet; 
    axisSet.xAxis.orthogonalCoordinateDecimal = CPTDecimalFromDouble(OrignalMinValueY); 

    CPTXYAxis *x = axisSet.xAxis; 
    CPTXYAxis *y = axisSet.yAxis; 






    x.titleTextStyle = axisTitleStyle; 

    x.titleOffset = 12.0f; 
    x.axisLineStyle = axisLineStyle; 
    x.labelingPolicy = CPTAxisLabelingPolicyNone; 
    x.labelTextStyle = axisTextStyle; 
    x.majorTickLineStyle = axisLineStyle; 

    x.tickDirection = CPTSignNegative; 
    x.minorTickLineStyle = nil; 
    x.coordinate = CPTCoordinateX; 

    CGFloat dateCount = [Reportdates count]; 
    NSMutableSet *xLabels = [NSMutableSet setWithCapacity:dateCount]; 
    NSMutableSet *xLocations = [NSMutableSet setWithCapacity:dateCount]; 

    // CPTAxisLabel *label = [[CPTAxisLabel alloc] initWithText:st textStyle:x.labelTextStyle]; 


     NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init]; 
     NSMutableSet *xMajorLocations = [NSMutableSet set]; 
     [formatter setPositiveFormat:@"0.##" ]; 
     for (double j = FinalMinValueX; j <= FinalMaxValueX; j += FinalIntervalValueX) { 
      CPTAxisLabel *label = [[CPTAxisLabel alloc] initWithText:[formatter stringFromNumber:[ NSNumber numberWithDouble:j ] ] textStyle:x.labelTextStyle]; 
      NSDecimal location = CPTDecimalFromInteger(j); 
      label.tickLocation = location; 
      label.offset = x.labelOffset; 

      if (label) { 
       [xLabels addObject:label]; 
      } 
      [xMajorLocations addObject:[NSDecimalNumber decimalNumberWithDecimal:location]]; 

     } 
     x.axisLabels = xLabels; 
     x.majorTickLocations = xLocations; 


    // 4 - Configure y-axis 

    //y.title = @"Price"; 
    y.titleTextStyle = axisTitleStyle; 
    y.titleOffset = -40.0f; 
    y.axisLineStyle = axisLineStyle; 
    y.majorGridLineStyle = gridLineStyle; 
    y.labelingPolicy = CPTAxisLabelingPolicyNone; 
    y.labelTextStyle = axisTextStyle; 
    y.majorTickLineStyle = axisLineStyle; 
    y.tickDirection = CPTSignPositive; 
    y.separateLayers= YES; 


    double majorIncrement = FinalIntervalValueY; 
    double minorIncrement = FinalIntervalValueY; 
    CGFloat yMax = FinalMaxValueY; // should determine dynamically based on max price 
    NSMutableSet *yLabels = [NSMutableSet set]; 
    NSMutableSet *yMajorLocations = [NSMutableSet set]; 
    NSMutableSet *yMinorLocations = [NSMutableSet set]; 
    NSNumberFormatter *formatter = [[NSNumberFormatter alloc] init]; 
    [formatter setPositiveFormat:@"0.##" ]; 
    for (double j = FinalMinValueY; j <= yMax; j += minorIncrement) { 
     CPTAxisLabel *label = [[CPTAxisLabel alloc] initWithText:[formatter stringFromNumber:[ NSNumber numberWithDouble:j ] ] textStyle:y.labelTextStyle]; 
     NSDecimal location = CPTDecimalFromInteger(j); 
     label.tickLocation = location; 
     label.offset = -20; 
     if (label) { 
      [yLabels addObject:label]; 
     } 
     [yMajorLocations addObject:[NSDecimalNumber decimalNumberWithDecimal:location]]; 
    } 
    y.axisLabels = yLabels; 
    y.majorTickLocations = yMajorLocations; 
    y.minorTickLocations = yMinorLocations; 

    if([ApplicationSettingOBJ.GB_VariableArrayY2 count ]>0) 
    { 
    CPTXYAxis *y2 = [[CPTXYAxis alloc] init] ; 
    y2.titleTextStyle = axisTitleStyle; 
    y2.coordinate = CPTCoordinateY; 
    y2.plotSpace = plotSpace2; 
    y2.labelingPolicy = CPTAxisLabelingPolicyNone; 
    y2.separateLayers= NO; 
    y2.majorGridLineStyle = nil; 

    y2.labelTextStyle = axisTextStyle; 
    y2.majorTickLineStyle = axisLineStyle; 
    y2.tickDirection = CPTSignNone; 
    y2.orthogonalCoordinateDecimal =CPTDecimalFromFloat(dateCount); 
    majorIncrement = FinalIntervalValueY2; 
    minorIncrement = FinalIntervalValueY2; 
    yMax = FinalMaxValueY2; // should determine dynamically based on max price 
    NSMutableSet *yLabels1 = [NSMutableSet set]; 
    NSMutableSet *yMajorLocations1 = [NSMutableSet set]; 
    NSMutableSet *yMinorLocations1 = [NSMutableSet set]; 

     for (double j = FinalMinValueY2; j <= yMax; j += minorIncrement) { 
        CPTAxisLabel *label = [[CPTAxisLabel alloc] initWithText:[formatter stringFromNumber:[ NSNumber numberWithDouble:j ] ] textStyle:y2.labelTextStyle]; 
       NSDecimal location = CPTDecimalFromInteger(j); 
       label.tickLocation = location; 
       label.offset = -20; 
       if (label) { 
        [yLabels1 addObject:label]; 
       } 
       [yMajorLocations1 addObject:[NSDecimalNumber decimalNumberWithDecimal:location]]; 

     } 

     y2.axisLabels = yLabels1; 
     y2.majorTickLocations = yMajorLocations1; 
     y2.minorTickLocations = yMinorLocations1; 

     axisSet.axes = [NSArray arrayWithObjects:x, y,y2, nil]; 



} 

Answer 1

plotSpace和plotSpace2是相同的對象（graph.defaultPlotSpace）。如果您想要兩個不同的y尺度，請創建一個新的繪圖空間並將其添加到圖形中。

CPTXYPlotSpace *plotSpace2 = [[CPTXYPlotSpace alloc] init]; 
[graph addPlotSpace:plotSpace2];