How to refer to dynamically created TextBlocks later on to update the text?

Hi,

I used a for-loop to create a number of TextBlocks and add them to a Grid. Later on, in an Event Handler, I want to refer to these TextBlocks and be able to change the text of either some or all, depending on my need.
The problem I'm having is how to refer to the TextBlocks, which were created using one generic name (txtBox) in common for each instance. I tried accessing using the txtBox.Name I set during creation, but that doesn't work.
Would appreciate any suggestions. Thanks!

I'm using Buttons now instead of TextBlocks, and put them into a List. I can access through the List, but I want to be able to access by the Name I've assigned. I've tried FindName method, but that doesn't find

        private void InitializeTunings()
       {

            for (int i = 0; i < 6; i++)
            {
                for (int j = 1; j < 13; j++)
                {
                    Button genericButton = new Button();
                    genericButton.Name = "Button" + j.ToString() + i.ToString();
                    genericButton.FontSize = 40;
                    genericButton.VerticalAlignment = VerticalAlignment.Stretch;
                    genericButton.HorizontalAlignment = HorizontalAlignment.Stretch;
                    genericButton.Foreground = new SolidColorBrush(Colors.White);

                    // Put into the List of TextBlocks
                    ButtonList.Add(genericButton);

THEN, IN A LATER EVENT HANDLER I HAVE THIS:

                    for (int i = 0; i < 6; i++)
                    {
                        for (int j = 0; j < 13; j++)
                        {
                            Button btnTEST = (Button)this.FindName("Button" + j.ToString() + i.ToString());
                            btnTEST.Content = "Btn" + j.ToString() + i.ToString();
                        }
                    }

THIS RETURNS AN EXCEPTION: "Object reference not set to an instance of an object". Which I take to mean that it did not find any Buttons with that Name. I also tried the name of the Grid parent control that holds the buttons instead of 'this', and any other possible parent control. But this still returned the same error.

3 Replies

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Sam Hobbs16y ago
Just create an array of buttons; do you understand about arrays?
0
Avtel Telav16y ago
I'm using Buttons now instead of TextBlocks, and put them into a List. I can access through the List, but I want to be able to access by the Name I've assigned. I've tried FindName method, but that doesn't find

        private void InitializeTunings()
       {

            for (int i = 0; i < 6; i++)
            {
                for (int j = 1; j < 13; j++)
                {
                    Button genericButton = new Button();
                    genericButton.Name = "Button" + j.ToString() + i.ToString();
                    genericButton.FontSize = 40;
                    genericButton.VerticalAlignment = VerticalAlignment.Stretch;
                    genericButton.HorizontalAlignment = HorizontalAlignment.Stretch;
                    genericButton.Foreground = new SolidColorBrush(Colors.White);

                    // Put into the List of TextBlocks
                    ButtonList.Add(genericButton);

THEN, IN A LATER EVENT HANDLER I HAVE THIS:

                    for (int i = 0; i < 6; i++)
                    {
                        for (int j = 0; j < 13; j++)
                        {
                            Button btnTEST = (Button)this.FindName("Button" + j.ToString() + i.ToString());
                            btnTEST.Content = "Btn" + j.ToString() + i.ToString();
                        }
                    }

THIS RETURNS AN EXCEPTION: "Object reference not set to an instance of an object". Which I take to mean that it did not find any Buttons with that Name. I also tried the name of the Grid parent control that holds the buttons instead of 'this', and any other possible parent control. But this still returned the same error.
0
Jaish Mathews16y ago
Hi,
Need you code to get an assumption.
0