Question

我有一个案例，我的应用程序连接到服务器以获取数据并在图表上绘图。当调用初始化绘图的函数时，图形会在错误的位置重新绘制，并自动将其自身更正回原位。这导致过程中的闪烁。我每10秒就有一个计时器连接到服务器。下面是绘图初始化代码。

    -(id)initWithHostingView:(CPTGraphHostingView *)hostingView andData:(NSMutableArray *)data
  {

  self = [super init];

if ( self != nil ) {
    self.hostingView = hostingView;
    self.graphData = data;
    self.graph = nil;
}

return self;
}

//如果我们还没有图形对象，这可以完成创建绘图的实际工作。

  -(void)initialisePlot:(NSUInteger)indexOfPlot
     {
     // Start with some simple sanity checks before we kick off
    if ( (self.hostingView == nil) || (self.graphData == nil) ) {
    NSLog(@"TUTSimpleScatterPlot: Cannot initialise plot without hosting view or        data.");
     return;
  }

 if ( self.graph != nil ) {
    NSLog(@"TUTSimpleScatterPlot: Graph object already exists.");
    return;
}

// Create a graph object which we will use to host just one scatter plot.

CGRect frame;
//CGRect frame = [self.hostingView bounds];
if(indexOfPlot == 0){
self.graph = [[CPTXYGraph alloc] initWithFrame:frame];

// Add some padding to the graph, with more at the bottom for axis labels.
self.graph.plotAreaFrame.paddingTop = 500.0f;
self.graph.plotAreaFrame.paddingRight = 20.0f;
self.graph.plotAreaFrame.paddingBottom = 50.0f;
self.graph.plotAreaFrame.paddingLeft= 20.0f;

// Tie the graph we've created with the hosting view.
self.hostingView.hostedGraph = self.graph;

// If you want to use one of the default themes - apply that here.
[self.graph applyTheme:[CPTTheme themeNamed:kCPTPlainWhiteTheme]];

// Create a line style that we will apply to the axis and data line.
CPTMutableLineStyle *lineStyle = [CPTMutableLineStyle lineStyle];
lineStyle.lineColor = [CPTColor redColor];
lineStyle.lineWidth = 2.0f;

// Create a text style that we will use for the axis labels.
CPTMutableTextStyle *textStyle = [CPTMutableTextStyle textStyle];
textStyle.fontName = @"Helvetica";
textStyle.fontSize = 14;
textStyle.color = [CPTColor blackColor];

// Create the plot symbol we're going to use.
CPTPlotSymbol *plotSymbol = [CPTPlotSymbol ellipsePlotSymbol];
plotSymbol.lineStyle = lineStyle;
plotSymbol.size = CGSizeMake(8.0, 8.0);

// Setup some floats that represent the min/max values on our axis.
float xAxisMin = -10;
float xAxisMax = 10;
float yAxisMin = 0;
float yAxisMax = 100;

// We modify the graph's plot space to setup the axis' min / max values.
CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *)self.graph.defaultPlotSpace;
plotSpace.xRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(xAxisMin) length:CPTDecimalFromFloat(xAxisMax - xAxisMin)];
plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(yAxisMin) length:CPTDecimalFromFloat(yAxisMax - yAxisMin)];

// Modify the graph's axis with a label, line style, etc.
CPTXYAxisSet *axisSet = (CPTXYAxisSet *)self.graph.axisSet;

axisSet.xAxis.title = @"Data X";
axisSet.xAxis.titleTextStyle = textStyle;
axisSet.xAxis.titleOffset = 30.0f;
axisSet.xAxis.axisLineStyle = lineStyle;
axisSet.xAxis.majorTickLineStyle = lineStyle;
axisSet.xAxis.minorTickLineStyle = lineStyle;
axisSet.xAxis.labelTextStyle = textStyle;
axisSet.xAxis.labelOffset = 3.0f;
axisSet.xAxis.majorIntervalLength = CPTDecimalFromFloat(2.0f);
axisSet.xAxis.minorTicksPerInterval = 1;
axisSet.xAxis.minorTickLength = 5.0f;
axisSet.xAxis.majorTickLength = 7.0f;

axisSet.yAxis.title = @"Data Y";
axisSet.yAxis.titleTextStyle = textStyle;
axisSet.yAxis.titleOffset = 40.0f;
axisSet.yAxis.axisLineStyle = lineStyle;
axisSet.yAxis.majorTickLineStyle = lineStyle;
axisSet.yAxis.minorTickLineStyle = lineStyle;
axisSet.yAxis.labelTextStyle = textStyle;
axisSet.yAxis.labelOffset = 3.0f;
axisSet.yAxis.majorIntervalLength = CPTDecimalFromFloat(10.0f);
axisSet.yAxis.minorTicksPerInterval = 1;
axisSet.yAxis.minorTickLength = 5.0f;
axisSet.yAxis.majorTickLength = 7.0f;

// Add a plot to our graph and axis. We give it an identifier so that we
// could add multiple plots (data lines) to the same graph if necessary.
CPTScatterPlot *plot = [[CPTScatterPlot alloc] init];
plot.dataSource = self;
plot.identifier = @"mainplot";
plot.dataLineStyle = lineStyle;
plot.plotSymbol = plotSymbol;
     //[self.graph reloadData];
[self.graph addPlot:plot];
}
if(indexOfPlot == 1){
    self.graph = [[CPTXYGraph alloc] initWithFrame:frame];

    // Add some padding to the graph, with more at the bottom for axis labels.
    self.graph.plotAreaFrame.paddingTop = 20.0f;
    self.graph.plotAreaFrame.paddingRight = 20.0f;
    self.graph.plotAreaFrame.paddingBottom = 600.0f;
    self.graph.plotAreaFrame.paddingLeft= 20.0f;

    // Tie the graph we've created with the hosting view.
    self.hostingView.hostedGraph = self.graph;

    // If you want to use one of the default themes - apply that here.
    [self.graph applyTheme:[CPTTheme themeNamed:kCPTPlainWhiteTheme]];

    // Create a line style that we will apply to the axis and data line.
    CPTMutableLineStyle *lineStyle = [CPTMutableLineStyle lineStyle];
    lineStyle.lineColor = [CPTColor redColor];
    lineStyle.lineWidth = 2.0f;

    // Create a text style that we will use for the axis labels.
    CPTMutableTextStyle *textStyle = [CPTMutableTextStyle textStyle];
    textStyle.fontName = @"Helvetica";
    textStyle.fontSize = 14;
    textStyle.color = [CPTColor blackColor];

    // Create the plot symbol we're going to use.
    CPTPlotSymbol *plotSymbol = [CPTPlotSymbol crossPlotSymbol];
    plotSymbol.lineStyle = lineStyle;
    plotSymbol.size = CGSizeMake(8.0, 8.0);

    // Setup some floats that represent the min/max values on our axis.
    float xAxisMin = -10;
    float xAxisMax = 10;
    float yAxisMin = 0;
    float yAxisMax = 100;

    // We modify the graph's plot space to setup the axis' min / max values.
    CPTXYPlotSpace *plotSpace = (CPTXYPlotSpace *)self.graph.defaultPlotSpace;
    plotSpace.xRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(xAxisMin) length:CPTDecimalFromFloat(xAxisMax - xAxisMin)];
    plotSpace.yRange = [CPTPlotRange plotRangeWithLocation:CPTDecimalFromFloat(yAxisMin) length:CPTDecimalFromFloat(yAxisMax - yAxisMin)];

    // Modify the graph's axis with a label, line style, etc.
    CPTXYAxisSet *axisSet = (CPTXYAxisSet *)self.graph.axisSet;

    axisSet.xAxis.title = @"Data X";
    axisSet.xAxis.titleTextStyle = textStyle;
    axisSet.xAxis.titleOffset = 30.0f;
    axisSet.xAxis.axisLineStyle = lineStyle;
    axisSet.xAxis.majorTickLineStyle = lineStyle;
    axisSet.xAxis.minorTickLineStyle = lineStyle;
    axisSet.xAxis.labelTextStyle = textStyle;
    axisSet.xAxis.labelOffset = 3.0f;
    axisSet.xAxis.majorIntervalLength = CPTDecimalFromFloat(2.0f);
    axisSet.xAxis.minorTicksPerInterval = 1;
    axisSet.xAxis.minorTickLength = 5.0f;
    axisSet.xAxis.majorTickLength = 7.0f;

    axisSet.yAxis.title = @"Data Y";
    axisSet.yAxis.titleTextStyle = textStyle;
    axisSet.yAxis.titleOffset = 40.0f;
    axisSet.yAxis.axisLineStyle = lineStyle;
    axisSet.yAxis.majorTickLineStyle = lineStyle;
    axisSet.yAxis.minorTickLineStyle = lineStyle;
    axisSet.yAxis.labelTextStyle = textStyle;
    axisSet.yAxis.labelOffset = 3.0f;
    axisSet.yAxis.majorIntervalLength = CPTDecimalFromFloat(10.0f);
    axisSet.yAxis.minorTicksPerInterval = 1;
    axisSet.yAxis.minorTickLength = 5.0f;
    axisSet.yAxis.majorTickLength = 7.0f;

    // Add a plot to our graph and axis. We give it an identifier so that we
    // could add multiple plots (data lines) to the same graph if necessary.
    CPTScatterPlot *plot = [[CPTScatterPlot alloc] init];
    plot.dataSource = self;
    plot.identifier = @"mainplot";
    plot.dataLineStyle = lineStyle;
    plot.plotSymbol = plotSymbol;
    //[self.graph reloadData];
    [self.graph addPlot:plot];

  }
}

我是否必须重新考虑它的初始化方式？

Answer 1

初始化frame。初始化图形时，您可能在那里有垃圾值，然后在将图形添加到托管视图时得到纠正。

CGRect frame = [self.hostingView bounds];

甚至只是

CGRect frame = CGRectZero;

闪烁的iOS核心情节图

1 个答案: