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Mouse left click over a label that overlaps its Picture Command Button

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I've been using a Picture Command Button with its label that overlaps the button, because I need also some text to clarify its function.

The well known problem is that the button doesn't change state when the user clicks over the label (i.e. the label is not "transparent" to mouse events).

In this thread I found a partial workaround by Luis, that works, but the user doesn't see the button in "pressed" state: the EVENT_COMMIT callback is executed, but the user hasn't any visual feedback from the button.

 

Is there a way to force the button in the "pressed" state when the user clicks over the callback?

Vix
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In claris non fit interpretatio

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Using LV from 7
Using LW/CVI from 6.0
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Message 1 of 6
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Vix,

 

We could not come up with an ideal solution for this scenario. Unfortunately, there is not a way to configure the "pressed" state of the control. We can however post a message to the UI that will trigger the EVENT_COMMIT case. Include Windows.h and then use the following code in the control callback:

 

case EVENT_COMMIT:
			//EVENT_COMMIT functionality
			break;
		case EVENT_LEFT_CLICK:
			//get label size and position
			GetCtrlAttribute (panelHandle, PANEL_PICTUREBUTTON, ATTR_LABEL_TOP, &top);
			GetCtrlAttribute (panelHandle, PANEL_PICTUREBUTTON, ATTR_LABEL_LEFT, &left);
			GetCtrlAttribute (panelHandle, PANEL_PICTUREBUTTON, ATTR_LABEL_WIDTH, &width);
			GetCtrlAttribute (panelHandle, PANEL_PICTUREBUTTON, ATTR_LABEL_HEIGHT, &height);
			
			//check if left click occurred over label
			if (eventData1 >= top && eventData1 < top + height && eventData2 >= left && eventData2 < left + width)
			{
				SetActiveCtrl (panelHandle, PANEL_PICTUREBUTTON);
				//get window handle
				GetPanelAttribute (panelHandle, ATTR_SYSTEM_WINDOW_HANDLE, (intptr_t*)&hwnd);
				//hide label so that event will not occur over label
				SetCtrlAttribute(panelHandle, PANEL_PICTUREBUTTON, ATTR_LABEL_VISIBLE, 0);
				//generate commit event
				SendMessage(hwnd, WM_LBUTTONDOWN, 0, 0);
				//unhide label
				SetCtrlAttribute(panelHandle, PANEL_PICTUREBUTTON, ATTR_LABEL_VISIBLE, 1);
			}
			break;

 The downside to this approach is that the label will be hidden so long as the mouse is down. I could not come up with a way to prevent this, which is why this solution is not ideal. However, it is the closest to the behavior you want that we could come up with.

 

Alternatively, another approach that may be a possibility is if you have access to the images that are on the buttons. If so, then you could actually embed the label text in the image. If that is a possibility, then that would avoid the need for all of these event workarounds.

 

National Instruments
Message 2 of 6
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The workaround you proposed sounds nice, but unfortunately the downside (label hidden as long as the mouse is down) is a problem fro me, so I can't use it.

Embed the labels into the images is not a solution for me, so I really hope there is another way...

 

I think that this need will be more common, because this is the behavior of the buttons in the MS Office 2010 ribbon bar (mostly of them have both an image and a label).

Vix
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In claris non fit interpretatio

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Using LW/CVI from 6.0
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Message 3 of 6
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Vix,

 

I agree that those solutions are not exactly ideal. Let me take a look a bit deeper at some other solutions and maybe we can come up with something better. However, it is likely that this is simply a hard limitation of the control and there may not be a way to do this.

National Instruments
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Message 4 of 6
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I hope that you can help me finding a better workaround, but in any case I think that a native "picture and text button" would be an useful improvement, so I posted a new product suggestion here.

Feel free to give kudos if you think it's a good idea Smiley Wink

Vix
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In claris non fit interpretatio

-------------------------------------------
Using LV from 7
Using LW/CVI from 6.0
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Message 5 of 6
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Solution
Accepted by vix

Vix,

 

Found a workaround. What we hadn't realized before is that the second click that we are generating is being caught as a EVENT_LEFT_DOUBLE_CLICK. With this knowledge, it is then very easy to implement this because we can now unhide the label in the EVENT_LEFT_DOUBLE_CLICK case. Check out the code below.

 

case EVENT_LEFT_CLICK:
			
			//get label size and position
			GetCtrlAttribute (panelHandle, PANEL_PICTUREBUTTON, ATTR_LABEL_TOP, &top);
			GetCtrlAttribute (panelHandle, PANEL_PICTUREBUTTON, ATTR_LABEL_LEFT, &left);
			GetCtrlAttribute (panelHandle, PANEL_PICTUREBUTTON, ATTR_LABEL_WIDTH, &width);
			GetCtrlAttribute (panelHandle, PANEL_PICTUREBUTTON, ATTR_LABEL_HEIGHT, &height);
			
			//check if left click occurred over label
			if (eventData1 >= top && eventData1 < top + height && eventData2 >= left && eventData2 < left + width)
			{
				SetActiveCtrl (panelHandle, PANEL_PICTUREBUTTON);
				//get window handle
				GetPanelAttribute (panelHandle, ATTR_SYSTEM_WINDOW_HANDLE, (intptr_t*)&hwnd);
				//hide label so that event will not occur over label
				SetCtrlAttribute(panelHandle, PANEL_PICTUREBUTTON, ATTR_LABEL_VISIBLE, 0);
				//generate commit event
				
				isFakeDouble = 1;
				SendMessage(hwnd, WM_LBUTTONDOWN, 0, 0);
				isFakeDouble = 0;
			}
			break;
		case EVENT_LEFT_DOUBLE_CLICK:
			if(isFakeDouble)
				SetCtrlAttribute(panelHandle, PANEL_PICTUREBUTTON, ATTR_LABEL_VISIBLE, 1);
			break;

 

National Instruments
Message 6 of 6
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