Solved

How do I setup a "onClick" event without using the object inspector?

Posted on 2002-06-28
2
284 Views
Last Modified: 2011-09-20
I have a form that has 56 charts on it.  I defined the charts as an array and set the properties in the code snippet below:

var
  TestProgressForm: TTestProgressForm;
  Charts : array[1..MAX_WFR_COL,1..MAX_WFR_ROW] of Tchart

Procedure TTestProgressForm.AssignChartProperties;
var col,row : integer;
    ChartSeries : TChartSeries;
begin
  for col := 1 to MAX_WFR_COL do begin
    for row := 1 to MAX_WFR_ROW do begin
      Charts[col,row] := Tchart.Create(TestProgressForm);
      Charts[col,row].Parent := TestProgressForm;
      BarSeries[col,row] := TBarSeries.Create(self);
      Charts[col,row].AddSeries(BarSeries[col,row]);
      charts[col,row].Enabled := TRUE;
      charts[col,row].Width := 80;
      charts[col,row].Height := 80;
      {set up properties here}
      charts[col,row].Top := 15 + (row-1)*(charts[col,row].Height + 5);
      charts[col,row].Left := 55 + (col-1)*(charts[col,row].Width + 5);
      with charts[col,row].Series[0] as TBarSeries do begin
        Clear;
        CustomBarWidth := 10;
        title := '';
        Marks.Visible := FALSE;
        ColorEachPoint := True;
        Marks.Style := smsPercent;
        Visible := False ;
        ShowInLegend := False;
        AutoMarkPosition := False;
        HorizAxis := aBottomAxis;
        VertAxis := aLeftAxis;
       end;
    end;
  end;
end;

What I would like to do is set up the code so that when I click or double click on the chart a new form is displayed showing the details.  The new form would be called TestDetails and would need to know which chart was double clicked on.   I do not how to go about defining this.

Thank you,
p
0
Comment
Question by:PattiGaultney
2 Comments
 
LVL 17

Accepted Solution

by:
geobul earned 100 total points
ID: 7117693
Hi,

1. In your form declaration add a new procedure declaration:

type
TTestProgressForm =
 ...
 public
  ...
  procedure ChartsClick(Sender: TObject); // common to all charts clicks
 ...
end;

2. Write that procedure in the 'implementation' section

procedure TTestProgressForm.ChartsClick(Sender: TObject);
begin
  if (Sender is TChart) then begin
    // Assign the chart to a property of TestDetails form
    TestDetails.TheChart := (Sender as TChart);
    // Show the form
    TestDetails.Show;
  end;
end;

3. Add next line somewhere in your loop above (when creating the charts:
  // This line assigns ChartsClick procedure as OnClick event handler (their declarations must be the same)
  charts[col,row].OnClick := ChartsClick;

4. In TestDetails form:

TestDetails =
private
  FChart: TChart; // new private field
....
public
  property TheChart: TChart read FChart write FChart; // new public property to hold a reference to a chart
...
end;

Now, in the events of TestDetails form you can use 'TheChart' to obtain a reference to the chart that has been clicked last. For example:

with TheChart.Series[0] as TBarSeries do begin
  ...
end;

Perhaps there is an easier way but that's coming up in my mind now and it's almost 5 AM here. If you need more info, please ask.

Regards, Geo
0
 
LVL 3

Expert Comment

by:sburck
ID: 7118983
I think it would be easier just to use some determining code in the OnClick handler... like this:

if (Sender as TChart).Name = "Chart1" then...

If there is position information, where you can determine
which chart is being accessed by it's X and Y coordinates, you can do that too, like

ChartID : integer;

ChartID = Idfunc((Sender as TChart).Left,(Sender as TChart).Bottom);

Where IDfunc returns the index as a function of left and right.

Finally, if you use the tag field when you create, putting in the number of the chart, then you can just do this:

...during creation of the charts
Charts[col,row].tag = col*100+row;

...during the OnClick
switch(Sender as TChart).tag)
...



0

Featured Post

Do You Know the 4 Main Threat Actor Types?

Do you know the main threat actor types? Most attackers fall into one of four categories, each with their own favored tactics, techniques, and procedures.

Join & Write a Comment

A lot of questions regard threads in Delphi.   One of the more specific questions is how to show progress of the thread.   Updating a progressbar from inside a thread is a mistake. A solution to this would be to send a synchronized message to the…
The uses clause is one of those things that just tends to grow and grow. Most of the time this is in the main form, as it's from this form that all others are called. If you have a big application (including many forms), the uses clause in the in…
Illustrator's Shape Builder tool will let you combine shapes visually and interactively. This video shows the Mac version, but the tool works the same way in Windows. To follow along with this video, you can draw your own shapes or download the file…
Polish reports in Access so they look terrific. Take yourself to another level. Equations, Back Color, Alternate Back Color. Write easy VBA Code. Tighten space to use less pages. Launch report from a menu, considering criteria only when it is filled…

706 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

21 Experts available now in Live!

Get 1:1 Help Now