How to make plugin icon active?

Question

I am thinking about a new QGIS plugin I'm going to do in near future.

So, I have some things, that could be hard for me. One of them is to making the plugin icon active when I click it.

For example, when I click on the "identify" tool in QGIS, it becomes active, but when I press the "pan" tool, the pan tool becomes active and the identify tool is no longer active.

I want do the same to my plugin icon.

Can you explain to me a little bit about how I'm supposed to do that?

Answer 1

I found a better way (for me), so I post this for those who are might need it.

First thing you have to do is add one more parameter to default add_action function:

checkable=False,

and set checkable method to action function.

So it could looks like:

def add_action(
    self,
    icon_path,
    text,
    callback,
    checkable=False,
    enabled_flag=True,
    add_to_menu=True,
    add_to_toolbar=True,
    status_tip=None,
    whats_this=None,
    parent=None):

    icon = QIcon(icon_path)
    action = QAction(icon, text, parent)
    action.triggered.connect(callback)
    action.setEnabled(enabled_flag)
    action.setCheckable(checkable)

    if status_tip is not None:
        action.setStatusTip(status_tip)

    if whats_this is not None:
        action.setWhatsThis(whats_this)

    if add_to_toolbar:
        self.toolbar.addAction(action)

    if add_to_menu:
        self.iface.addPluginToVectorMenu(
            self.menu,
            action)

    self.actions.append(action)

    return action

So, according to this, when you gonna create action you have to add this line as well.

def initGui(self):    
        icon_path = 'your_path'
        self.add_action(
            icon_path,
            text=self.tr(u"Random text"),
            callback=self.function,
            checkable=True,
            parent=self.iface.mainWindow())

Second thing. Create file, where you will put your tool class.

tool.py

class Tool(QgsMapTool):
    def __init__(self, iface):
        canvas = iface.mapCanvas()
        QgsMapTool.__init__(self, canvas)
        self.canvas = canvas
        self.iface = iface

The last thing you have to do is create function in your main file to handle tool.

def function(self):
    self.tool = Tool(self.iface)
    self.tool.setAction(self.actions[0])
    self.iface.mapCanvas().setMapTool(self.tool)
    self.toolname = 'your_plugin_name'

If someone wants to know more I leave you with this link.