Updating variable values dynamically

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    • Updating variable values dynamically

      I'm using the GUI_DispDecAt() API to display a value at a particular position. However, I want to update this value within a loop. The values are getting overwritten. Is there anyway to updated the digits alone?

      int var = 100;

      for(int k =0; k <10; k++) {


      Please let me know how to go about this. Thank You!
    • Hi,

      Your suggestion works. However, I got the same output using the function GUI_DispStringAtCEOL(). Is there a way to change the way the area is refreshed? It looks like a transparent rectangle sliding down and then new value is displayed. Is there a way to change this animation? I want just the digit to change.

      Thank You.

      The post was edited 1 time, last by jysrvnn ().

    • Hi,

      when you are displaying a new value, it is written above the old value. Therefore, the background of the value has to be cleared, so that only the new value is visible in the end. You can clear the background of a window with GUI_Clear().

      Note that GUI_Clear() clears the entire screen with the currently set background color. You can limit the area to be cleared with GUI_ClearRect().

      If emWin widgets are included in your library or source code, using the TEXT widget will be probably a lot easier. The TEXT widget also has a decimal mode for displaying numeric values. After it has been created, to update the text or value, you only have to call TEXT_SetText() or TEXT_SetDec().

      Best regards,
    • Hi, using the Text widget is a good idea. I'm creating a Text widget within my Window. However, I would like to update it within a different function. How to get the handle of the dialog item (that is the Text item)?

      static const GUI_WIDGET_CREATE_INFO _aDialogCreate[] = {
      { WINDOW_CreateIndirect, "Window", ID_WINDOW_0, 35,50, 320, 480, 0, 0x0, 0 },
      { GRAPH_CreateIndirect, "Graph", ID_GRAPH_0, 0, 38, GRAPH1_LEN, GRAPH1_WID, 0, 0x0, 0 },
      { TEXT_CreateIndirect, "Text", ID_TEXT_0, 192, 5, 120, 30, 0, 0x0, 0 }

      * _cbDialog

      static void _cbDialog(WM_MESSAGE * pMsg) {

      WM_HWIN hItem;
      switch (pMsg->MsgId) {
      case WM_INIT_DIALOG:

      // Initialization of 'Window'

      hItem = pMsg->hWin;
      WINDOW_SetBkColor(hItem, GUI_MAKE_COLOR(0x00000000));//0x00000000

      // Initialization of 'TEXT'

      hItem = WM_GetDialogItem(pMsg->hWin, ID_TEXT_0);
      TEXT_SetTextAlign(hItem, GUI_TA_HCENTER | GUI_TA_VCENTER);
      TEXT_SetFont(hItem, Roboto_30);
      TEXT_SetTextColor(hItem, UI_GREEN);
      TEXT_SetText(hItem, "120");


      * Update_Text

      static void _UpdateText(int val) {

      WM_HWIN Txt;

      char buff[10];
      for(int k =0; k < 10; k++) {
      sprintf(buff, "%i", val);
      Txt = WM_GetDialogItem(pMsg->hWin, ID_TEXT_0); //here it's throwing error because the pMsg->hWin handle is not defined here
      TEXT_SetText(Txt, buff);
    • Hi,

      you can get the handle of the TEXT widget by calling WM_GetDialogItem(hParent, ID_TEXT_0) where hParent is the parent window of the child window. In this case, the dialog is the parent of the TEXT widget.

      In your function _UpdateText(), you can't call pMsg->hWin without having a pointer to a WM_MESSAGE structure. You could save the handle of the parent window as a static variable in order for the function to work.

      Best regards,