How to make a flex button keep its state through screen change

[ArendZA]

Hello,

I'm busy working on my first touchGFX project and I am using flex buttons instead of toggle buttons. I set the trigger to toggle and change the color of the button which works really well. The issue I am facing is that if I set a button to the off state when its default state in on and change screens the buttons will all reset to on when returning to the screen.

I notice the same thing happens even with toggle buttons. Is there any way to save the state of the button when leaving the screen so that when I return it will still be in the correct state?

Thanks in advance.

[mƎALLEm]

Hello,

This is my trial. This is something I used before to save the status of a toggle button:

Create a .hpp file that will manage the persistance of the button status and name it persistance.hpp.

Its content will be:

 

#ifndef PERSISTANCE_HPP
#define PERSISTANCE_HPP
using namespace touchgfx;
class Persistance
{

 public:

 Persistance()
 {
 }
 static int GetButtonStatus(void)
 {
 return button_status;
 }
 static void SetButtonStatus(int temp)
 {
 button_status = temp;
 }
 

 private:
 static int button_status;
};

#endif // PERSISTANCE_HPP

 

Then put that file in the path: TouchGFX\gui\include\gui\common\

Include: persistance.hpp in your screenview.cpp (xxxScreenView.cpp )

 

#include <gui/common/persistance.hpp>

 

In Setup Screen, set the value of the button:

 

xxxScreenView::setupScreen()
{
button.forceState(Persistance::GetButtonStatus);
}

 

you call Persistance::SetButtonStatus() to save the status of the button when the button status changed: 

 

Persistance::SetButtonStatus(<set the status of the button>)

 

 

[ArendZA]

Awesome, just implemented this. Works good, busy working on a solution for multiple buttons thats not just creating 20 of the same functions and variables.

[mƎALLEm]

---

@ArendZA wrote:

busy working on a solution for multiple buttons thats not just creating 20 of the same functions and variables.

---

You can manage that by a table:

 

 static int GetButtonStatus(int button_index)
 {
 return button_status[button_index];
 }
 static void SetButtonStatus(int button_value, int button_index)
 {
 button_status[button_index] = button_value;
 }
 

 private:
 static int button_status[20]; /* 20 buttons*/

 

But need to manage the button_index that should not exceed 20 in your case. 

Also use enumeration to set/get button status index for code visibility.

[ArendZA]

Thanks I was busy doing something similar when i saw your message.

For people who may find this thread in the future, here's the code for different types of widgets that I have now gotten working.
Create the header file like above and in that file is where you will be storing your values. You'll need 2 functions for each widget 1 to set the value the other to fetch the value when you open the screen.

Flex buttons:

static int getButtonState(int buttonIndex)

{

int temp = button_states[buttonIndex];

return temp;

}



static void setButtonState(int buttonIndex, int buttonState)

{

button_states[buttonIndex] = buttonState;

}

This can be used like this:

void Screen2View::setupScreen()

{

Screen2ViewBase::setupScreen();

int temp = Persistance::getButtonState( 0 ); /* This matches with the correct button in the array */

*Button*.forceState(temp);

}

And to set the value use something like this in the callback:

int buttonState = ofBtn.getPressed();

if(buttonState == pressed){

Persistance::setButtonState(Button, pressed /* 1 */);

}
else

{

Persistance::setButtonState(Button, unpressed /* 0 */);

}

For sliders its easy as well, 2 functions you'll need:

static void setSpeedStatus ( int speed)

{

speed_status = speed;

}



static int getSpeedStatus()

{

return speed_status;

}

In the callback:

void Screen2View::speedUpdate(int value)
{
 Persistance::setSpeedStatus(value);
}

In void Screen2View::setupScreen()
Use this:

int speed = Persistance::getSpeedStatus();

speedSlider.setValue(speed);

Radio buttons 2 functions again:

static void setRadioGroup1 (int selectedRadio){

radio_group1_status = selectedRadio;

}



static int getRadioGroup1 ( void )

{

return radio_group1_status;

}
private:
static int radio_group1_status;

In the callback:

Persistance::setRadioGroup2(0Button);

To set the value:

void Screen2View::setupScreen()

{

Screen2ViewBase::setupScreen();

int radioGroup1Button = Persistance::getRadioGroup1();

switch(radioGroup1Button)

{

case fwdButton:

Btn.setSelected(pressed);

break;

case revButton:

Btn.setSelected(pressed);

break;

case faultButton:

Btn.setSelected(pressed);

break;

}

One thing to remember for radio buttons, if a button has the value of 0 it will now be the default value unless you initialize the storage variable to another number

[ArendZA]

Yeah sorry about that was excited for my lunch break and typed it out quick

[Marc_LM]

@mƎALLEm, where is Persistance constructed (memory mapped) ?
Also isn't this the same as adding members in FrontendApplication/Model to have them globally accessible?

[FJB2069]

Doesn't this demo show how to do this using MVP?   

https://youtu.be/RJlwEMCTgsM?si=wvrITwf52WXhQBYO 

 

seems like creating a Persistance class method may be easier?