Following the tutorial creates an empty/blank view

[zkhalapyan]

I followed the tutorial to create the bar chart, and the result was an empty screen. I am assuming the problem is in the initialization code:

JBBarChartView *barChartView = [[JBBarChartView alloc] init];

Can someone double check this and see if they can reproduce the issue on an empty project?

[terryworona]

Did you set the datasource and delegate? Add the barChartView as a subview?

Check out the demo project for a complete example.

[zkhalapyan]

Yes, followed the tutorial completely - the graph works only when initialized with initWithFrame. The following code does not work:

JBBarChartView *barChartView = [[JBBarChartView alloc] init];
barChartView.delegate = self;
barChartView.dataSource = self;
barChartView.backgroundColor = [UIColor grayColor];
[self.view addSubview:barChartView];

[barChartView reloadData];

Used the following mock delegate functions:

- (NSInteger)numberOfBarsInBarChartView:(JBBarChartView *)barChartView
{
    return 10;
}

- (CGFloat)barChartView:(JBBarChartView *)barChartView heightForBarViewAtAtIndex:(NSInteger)index
{
    return 100;
}

[yeahdongcn]

Try this.

• (CGFloat)barChartView:(JBBarChartView *)barChartView heightForBarViewAtAtIndex:(NSInteger)index
  {
  return arc4random() % 20;
  }

[terryworona]

It is recommended that you initialize any JB* chart view with initWithFrame:... even if it is with CGRectZero.

As well, you need to supply each bar with a height (random or otherwise) as suggested by @yeahdongcn.

[zkhalapyan]

@yeahdongcn I tried with the random bar chart heights, but the resulting view is still empty.

@terryworona If the library is not going to work with the empty initializers, should we update the tutorial?

Thanks for the support guys!

[terryworona]

@zkhalapyan I added default init functions for both line and bar charts.

You can now initialize JBLineChartView and JBBarChartView with init as well as initWithFrame:.

Note: you must set a frame if you start supplying headers and footers, otherwise an assert will catch the mis-matched layout constraints.

I also updated the (demo) line & bar chart controllers to use base -init to demonstrate the change.

Hope this helps.

[yeahdongcn]

This code works for me.
JBBarChartView *barChartView = [[JBBarChartView alloc] initWithFrame:CGRectMake(10, 64, 300, 200)];
barChartView.autoresizingMask = UIViewAutoresizingFlexibleWidth;
barChartView.layer.borderWidth = 1;

[simonbromberg]

In view did load for my view controller have the following :
JBBarChartView* chartView = [[JBBarChartView alloc] init]; //also tried intiWithFrame
chartView.delegate = self;
chartView.dataSource = self;
[self.view addSubview:chartView];

Nothing loads in the view and the delegate/datasource methods don't get called...

[terryworona]

@simonbromberg you have to call reloadData to invoke the drawing.

[simonbromberg]

Ah, thanks, that fixed it. I know it's kind of implied, since you're following the UITableView structure, but you should consider mentioning that in the readme.

Another
It's also shifted down vertically for some reason, even though its frame matches the container view's frame exactly. Know why it's doing this? Is it because it's expecting a header?

Now I have: (in viewDidLoad)

JBChartView* chartView = [[JBBarChartView alloc] initWithFrame:self.graphContainer.frame];       
chartView.layer.borderWidth = 1;
chartView.delegate = self;
chartView.dataSource = self;
[self.graphContainer addSubview:chartView];
[chartView reloadData];

The grey area is the background for the container view.

[terryworona]

Trying initializing the chartView with the container's bounds?

JBChartView* chartView = [[JBBarChartView alloc] initWithFrame:self.graphContainer.bounds];       

[simonbromberg]

Thanks, that fixed it.

[ridzkurniawan]

it gives me a blankbar on the last one, for example i set number of bar 4 then it will display 3 with a single large space for the fourth one
how could I fix this?

here is the code

• (void)viewDidLoad
  {
  [super viewDidLoad];
  // Do any additional setup after loading the view.

  barChartView = [[JBBarChartView alloc] init];
  barChartView.dataSource = self;
  barChartView.delegate = self;
  [self.view addSubview:barChartView];

  barChartView.backgroundColor = [UIColor grayColor];

  barChartView.frame = CGRectMake(60, 100, 200, 200);
  [barChartView reloadData];
  }

• (void)didReceiveMemoryWarning
  {
  [super didReceiveMemoryWarning];
  // Dispose of any resources that can be recreated.
  }

-(CGFloat)barChartView:(JBBarChartView *)barChartView heightForBarViewAtIndex:(NSUInteger)index
{
switch (index) {
case 0:
return 1.0;
break;
case 1:
return 0.9;
break;
case 2:
return 0.7;
break;

    default:return 0.2;
        break;
}
//return 5; // height of bar at index

}

• (NSUInteger)numberOfBarsInBarChartView:(JBBarChartView *)barChartView
  {
  return 4; // number of bars in chart
  }

• (UIColor *)barChartView:(JBBarChartView *)barChartView colorForBarViewAtIndex:(NSUInteger)index{
  switch (index) {
  case 0:
  return [UIColor redColor];
  break;
  case 1:
  return [UIColor yellowColor];
  break;
  case 2:
  return [UIColor greenColor];
  break;

  default: return [UIColor blueColor];
      break;
  

  }
  }

• (UIColor *)barSelectionColorForBarChartView:(JBBarChartView *)barChartView
  {
  return [UIColor whiteColor]; // color of selection view
  }

@EnD

thanks

[terryworona]

@ridzkurniawan try setting the chart's minimumValue to 0.

[ridzkurniawan]

@terryworona Thanks, it works now

[MVakas]

How can I set the label of a bar?

[terryworona]

@MVakas the bar's do not have labels (by default); the demo project uses a footer subview to label each bar.

You can create your own custom bar views via:

- (UIView *)barChartView:(JBBarChartView *)barChartView barViewAtIndex:(NSUInteger)index

From there, you can place your own label on a bar and manage it yourself.