Added a Graph Widget but nothing is shown on the display

[HPam.1]

I downloaded GraphApplication from this post to try Graph Widget.

https://community.st.com/s/question/0D50X0000ALvsTfSQJ/how-to-start-using-the-graph-widget-from-touchgfxopenrepository-in-touchgfx-designer

I am using STM32F429i-Discovery Board to display this graph, after adding necessary code to my Screen1View.cpp and importing these files,

Graph.hpp, GraphLine.hpp, AbstractGraph.hpp ,

Graph.cpp, GraphLine.cpp, AbstractGraph.cpp.

The graph is still not shown on my Screen1View. On the display, it just show the blue background image from the GraphApplication example.

Here is my code.

File Screen1View.hpp
 
#ifndef SCREEN1VIEW_HPP
#define SCREEN1VIEW_HPP
 
#include <gui_generated/screen1_screen/Screen1ViewBase.hpp>
#include <gui/screen1_screen/Screen1Presenter.hpp>
#include <Graph.hpp>
 
class Screen1View : public Screen1ViewBase
{
public:
    Screen1View();
    virtual ~Screen1View() {}
    virtual void setupScreen();
    virtual void tearDownScreen();
    virtual void handleTickEvent();
protected:
 
    int tickCounter;
    Graph graph;
};
 
#endif // SCREEN1VIEW_HPP

File Screen1View.cpp
 
#include <gui/screen1_screen/Screen1View.hpp>
 
static int randomNumberBetween(int lowest, int highest);
static int randomNumberBetween(int lowest, int highest)
{
#ifdef SIMULATOR
    return lowest + (highest - lowest) * rand() / RAND_MAX;
#else
    uint32_t random = (touchgfx::HAL::getInstance()->getCPUCycles() * HAL::getInstance()->getCPUCycles());
    return lowest + (random % (highest - lowest));
#endif
}
 
Screen1View::Screen1View()
{
 
}
 
void Screen1View::setupScreen()
{
    //Screen1ViewBase::setupScreen();
 
    // Place the graph on the screen
    graph.setXY(20, 20);
 
    // Set the outer dimensions and color of the graph
    graph.setup(440, 200, Color::getColorFrom24BitRGB(0xFF, 0xFF, 0xAC));
 
    // Set the range for the x and y axis of the graph. That is
    // the max and min x/y value that can be displayed inside the
    // dimension of the graph.
    graph.setRange(0, 50, 0, 200);
 
    // Set the line width in pixels
    graph.setLineWidth(2);
 
    add(graph);
}
 
void Screen1View::tearDownScreen()
{
    Screen1ViewBase::tearDownScreen();
}
 
void Screen1View::handleTickEvent()
{
    // Number of ticks between inserting a point in the graph
    int interval = 5;
 
    tickCounter++;
 
    if (tickCounter % interval == 0)
    {
        // Insert a point in the graph.
        // The Y value is a random number in the y range of the graph.
        graph.addValue(tickCounter / interval, randomNumberBetween(graph.getRangeBottom(), graph.getRangeTop()));
    }
 
    if (tickCounter == 37 * interval)
    {
        // Change the range of the Y axis
        graph.setRange(0, 50, 0, 400);
        graph.invalidate();
    }
 
    if (tickCounter == 50 * interval)
    {
        // Reset the graph and start over
        graph.setRange(0, 50, 0, 200);
        graph.setLineWidth(2);
        graph.clear();
        graph.invalidate();
 
        tickCounter = 0;
    }
}

Attached my project. Just unzip the workspace, open workspace1\GraphTest\STM32CubeIDE\.cproject and use workspace1 as workspace directory.

Edit 1:

I found that i should add a canvas buffer in main.c , i will try to convert the example main.cpp to main.c

Edit 2:

I added a canvas buffer 3600 to screen 1 through TouchGfx designer, and the graph line started to appear at last!

[Alexandre RENOUX]

Hello,

Is your issue resolved ?

The project is pretty old so I will port it to the TouchGFX 4.13.0 as a simple GUI you can run in the simulator, so that you can then import it to any Application Template.

For you interest, a Graph widget is currently being made and will probably be available in Designer around October.

/Alexandre

[Alexandre RENOUX]

Hello again,

You will find enclosed the UI for the Graph example (made with TouchGFX Designer 4.14 available via the TouchGFX Generator in CubeMX 6.0.0).

I believe your issue was indeed the Canvas buffer.

Please when doing an application, always test on the simulator, it often gives pretty good insight on why it's not working when there's a problem.

/Alexandre

[HPam.1 · Accepted solution]

Hello Alexandre,

My issue is resolved after adding the Canvas buffer. Though I don't know how to calculate the buffer size, I just punched in the default according to the example

Thank you very much, i'll try that graph example after I upgrade to 4.14.