TabIndex does not work correctly

Question

I have a windows form application. On the form there are three groupboxs. Each groupbox contains some controls. Please see the image. There is a groupbox "flag" that contains a few checkboxs. "flag" is inside in "groupbox1". I used Tab key to go through each control but it doesn't work for checkboxs in "flag". I did set proper tabindex for each control. It works for textboxs and buttons but checkboxs. Why? Thanks for help. EDIT ``` // groupBox2 // this.groupBox2.Controls.Add(this.pictureBox10); this.groupBox2.Controls.Add(this.pictureBox9); this.groupBox2.Controls.Add(this.pictureBox8); this.groupBox2.Controls.Add(this.pictureBox7); this.groupBox2.Controls.Add(this.chkStoplight); this.groupBox2.Controls.Add(this.lblStoplight); this.groupBox2.Controls.Add(this.chkIsCount); this.groupBox2.Controls.Add(this.chkExceptionFlag); this.groupBox2.Controls.Add(this.chkIsActive); this.groupBox2.Controls.Add(this.lblIsActive); this.groupBox2.Controls.Add(this.lblExceptionFlag); this.groupBox3.Con…

Accepted Answer

For System.Windows.Forms.GroupBox:

You should make sure that your GroupBox `flag` has an appropriate TabIndex set.

From MSDN - How to: Set the Tab Order on Windows Forms:

Additionally, by default, a GroupBox control has its own TabIndex value, which is a whole number. A GroupBox control itself cannot have focus at run time. Thus, each control within a GroupBox has its own decimal TabIndex value, beginning with .0. Naturally, as the TabIndex of a GroupBox control is incremented, the controls within it will be incremented accordingly. If you changed a TabIndex value from 5 to 6, the TabIndex value of the first control in its group automatically changes to 6.0, and so on

Also, make sure the TabStop property of your GroupBox `flag` is not set to false. I believe false is the default.

For System.Windows.Controls GroupBox:

Make sure that the GroupBox.IsTabStop property is set. This also defaults to false.

Update: It appears that all of your controls are being added to `groupBox3`. You should make sure that each of them is being added only to its containing groupbox. For example, `checkBox1`, `checkBox2`, and `checkBox3` should all be added to `flag`, which itself should be added to `groupBox1`. `groupBox3` should only contain Back, Next, Finish, and Cancel.

TabIndex does not work correctly

Solution

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