SHLineGraphView - Set graph origin value - ios

Question

Using SHLineGraphView
I want to specify the origin of my graph to a different value other than 0.
The issue was already created here Min/Max draw Y axis but the owner seems uninterested in solving it.
This is what I have now
SHLineGraphView.m
#define BOTTOM_MARGIN_TO_LEAVE 30.0
#define TOP_MARGIN_TO_LEAVE 30.0
#define INTERVAL_COUNT 10
//INTERVAL_COUNT - 3 -> Limits the y-axis to 60 but
//not the entire graph.
- (void)drawYLabels:(SHPlot *)plot {
double yRange = [_yAxisRange doubleValue]; // this value will be in dollars
double yIntervalValue = yRange / INTERVAL_COUNT;
double intervalInPx = (self.bounds.size.height - BOTTOM_MARGIN_TO_LEAVE ) / (INTERVAL_COUNT - 3);
NSLog(#"interval px %f",intervalInPx);
NSMutableArray *labelArray = [NSMutableArray array];
float maxWidth = 0;
for(int i= 0; i <= INTERVAL_COUNT - 3 ; i++){
CGPoint currentLinePoint = CGPointMake(_leftMarginToLeave, i * intervalInPx);
CGRect lableFrame = CGRectMake(0, currentLinePoint.y - (intervalInPx / 2), 100, intervalInPx);
NSLog(#"label frame %f", lableFrame.origin.y);
//if(i != 0) {
UILabel *yAxisLabel = [[UILabel alloc] initWithFrame:lableFrame];
yAxisLabel.backgroundColor = [UIColor clearColor];
yAxisLabel.font = (UIFont *)_themeAttributes[kYAxisLabelFontKey];
yAxisLabel.textColor = (UIColor *)_themeAttributes[kYAxisLabelColorKey];
yAxisLabel.textAlignment = NSTextAlignmentCenter;
float val = (yIntervalValue * (10 - i));
NSLog(#"value %f", val);
if(val > 0){
yAxisLabel.text = [NSString stringWithFormat:#"%.1i%#", (int)val, _yAxisSuffix];
} else {
yAxisLabel.text = [NSString stringWithFormat:#"%.0f", val];
}
[yAxisLabel sizeToFit];
CGRect newLabelFrame = CGRectMake(0, currentLinePoint.y - (yAxisLabel.layer.frame.size.height / 2), yAxisLabel.frame.size.width, yAxisLabel.layer.frame.size.height);
yAxisLabel.frame = newLabelFrame;
if(newLabelFrame.size.width > maxWidth) {
maxWidth = newLabelFrame.size.width;
}
[labelArray addObject:yAxisLabel];
[self addSubview:yAxisLabel];
//}
}
viewController.m
_graphView.yAxisRange = #(200);
The y-axis is ok but the graph is still plotted from origin 0.

Answer 1

Create a yAxisMinValue property
#property (nonatomic, strong) NSNumber *yAxisMinValue;
...and update your drawYLabels function as follows:
- (void)drawYLabels:(SHPlot *)plot {
double yRange = [_yAxisRange doubleValue]; // this value will be in dollars
double yRangeMin = [_yAxisMinValue doubleValue];
NSLog(#"yRange: %f", yRange);
NSLog(#"yRangeMin: %f", yRangeMin);
double yIntervalValue = (yRange - yRangeMin) / INTERVAL_COUNT;
NSLog(#"yIntervalValue: %f", yIntervalValue);
double intervalInPx = (self.bounds.size.height - BOTTOM_MARGIN_TO_LEAVE ) / (INTERVAL_COUNT +1);
NSMutableArray *labelArray = [NSMutableArray array];
float maxWidth = 0;
for(int i= INTERVAL_COUNT + 1; i >= 0; i--){
NSLog(#"i = %d",i);
CGPoint currentLinePoint = CGPointMake(_leftMarginToLeave, i * intervalInPx);
CGRect lableFrame = CGRectMake(0, currentLinePoint.y - (intervalInPx / 2), 100, intervalInPx);
if(i != 0) {
UILabel *yAxisLabel = [[UILabel alloc] initWithFrame:lableFrame];
yAxisLabel.backgroundColor = [UIColor clearColor];
yAxisLabel.font = (UIFont *)_themeAttributes[kYAxisLabelFontKey];
yAxisLabel.textColor = (UIColor *)_themeAttributes[kYAxisLabelColorKey];
yAxisLabel.textAlignment = NSTextAlignmentCenter;
float val = (yIntervalValue * (10 - i)) + yRangeMin;
if(val > yRangeMin){
yAxisLabel.text = [NSString stringWithFormat:#"%.1f%#", val, _yAxisSuffix];
NSLog(#"%.1f%#", val, _yAxisSuffix);
} else {
yAxisLabel.text = [NSString stringWithFormat:#"%.1f", val];
NSLog(#"%.1f", val);
}
[yAxisLabel sizeToFit];
CGRect newLabelFrame = CGRectMake(0, currentLinePoint.y - (yAxisLabel.layer.frame.size.height / 2), yAxisLabel.frame.size.width, yAxisLabel.layer.frame.size.height);
yAxisLabel.frame = newLabelFrame;
if(newLabelFrame.size.width > maxWidth) {
maxWidth = newLabelFrame.size.width;
}
[labelArray addObject:yAxisLabel];
[self addSubview:yAxisLabel];
}
}