Android Menu Easy to create

There are 4 classes related to menu in Android:

Menu: The parent window for menus, which is used to create a menu, a parent interface such as Submenu,contentmenu,menuitem, Submenuyo for creating submenus, Contentmenu for creating context menus, MenuItem is used to create a menu item.

Menu Development Basic ideas: 1, with Oncreateoptionsmenu (Menu menu) (For options menus, or with Ncreatecontentmenu (Contentmenu Contentmenu,view Source,contentmenuinfo info) For the context menu , create a menu, and invoke the Menu object's method in the change method to add an item or submenu; 2. Rewrite activity's onoptionsmenuselected () (For Options menu, oncontentitemselected () method, for context menu) method corresponding event.

There are 3 types of menus:

One, the Options menu (Normal menu)

The so-called normal menu, click the menu button to pop-up menus, simple to create Options menu, the code is as follows:　　

public class Mainactivity extends Appcompatactivity {
    @Override
    protected void OnCreate (Bundle savedinstancestate) {
        Super.oncreate (savedinstancestate);
        Setcontentview (R.layout.activity_main);
    }
    @Override
    public boolean Oncreateoptionsmenu (Menu menu) {
Getmenuinflater (). Inflate (R.menu.mainmenu,menu);//Create a menu from an XML file, where R.menu.mainmenu asks the menu file to add the defined XML file.

Menu.add (0,0,0, "menu Test");//Add a menu option with code
Menu.add (0,1,0, "Text settings");
Submenu submenu = Menu.addsubmenu (0,6,0, "Sub-menu Test");//Adding a submenu
Submenu.add (0,2,0, "I am submenu 1");//Add a submenu item
Submenu.add (0,3,0, "I am submenu 2");
Submenu.add (0,4,0, "I am submenu 3");
return true;
}
@Override
public boolean onoptionsitemselected (MenuItem item) {
return super.onoptionsitemselected (item);
Switch (Item.getitemid ()) {
Case 0:
Toast.maketext (This, "menu test", Toast.length_short). Show ();
Break
Case 1:
Toast.maketext (This, "Text settings", Toast.length_short). Show ();
Break
Case 2:
Toast.maketext (This, "I am submenu 1", Toast.length_short). Show ();
Break
Case 3:
Toast.maketext (This, "I am submenu 2", Toast.length_short). Show ();
Break
Default
Toast.maketext (This, "Who am I?") ", Toast.length_short). Show ();
Break
}
return true;
}
}

Second, the context menu

A menu that pops up when a control is long pressed is called a context menu (like a menu that pops up with a right mouse button), and you must register a context menu with the control in advance:

Add a button to the Activity_main.xml file and register it with the context menu.

1. Register the context menu for the control that you want to register the context menu for, such as registerforcontextmenu (button);

2. Rewrite the Oncreatecontentmenu () method and create a menu item within the method;

3, rewrite the oncontentitemselected () method to handle menu click events,

The simple example code is as follows:

　　

public class Mainactivity extends Appcompatactivity {
Button btn;

@Override
protected void OnCreate (Bundle savedinstancestate) {
Super.oncreate (savedinstancestate);
Setcontentview (R.layout.activity_main);
BTN = (Button) Findviewbyid (R.id.button);
Registerforcontextmenu (BTN);
}

@Override
public void Oncreatecontextmenu (ContextMenu menu, View V, contextmenu.contextmenuinfo menuinfo) {
Super.oncreatecontextmenu (menu, V, menuinfo);
if (v.getid () = = R.id.button) {
Menu.add (0, 0, 0, "context menu Test");
Menu.add (0, 1, 0, "context menu Test 1");
Menu.add (0, 2, 0, "context menu Test 2");

Menu.setgroupcheckable (0, True, true);//Set 3 menu items to a single-selection menu item
Menu.setheadertitle ("Select background color"); Set the caption, icon for the context menu
Menu.setheadericon (R.DRAWABLE.TT); Setting the context menu icon
}
}

@Override
public boolean oncontextitemselected (MenuItem item) {
return super.oncontextitemselected (item);
Switch (Item.getitemid ()) {
Case 0:
Toast.maketext (This, "context menu Test", Toast.length_short). Show ();
Break
Case 1:
Toast.maketext (This, "context menu Test 1", Toast.length_short). Show ();
Break
Case 2:
Toast.maketext (This, "context menu Test 2", Toast.length_short). Show ();
Break
Default
Break
}
return true;
}
}

Three, pop-up menu:

PopupMenu represents a pop-up menu that pops up on the specified component and appears above or below the component. Sensory function can be replaced with listdialog, do not know which is better.

There are 2 ways to create a menu in Android:

First, using XML to define the menu

When you define a menu file in the Res/menu directory, such as a Menu1.xml file, the menu file must have a <menu> root node,<menu> tag without any attributes, but can be nested in <item> to represent a submenu.

Three tags commonly used in the menu <menu>, <item>, <group>

1.1 <item> represents a menu option that cannot be nested, and has several common properties as follows:

The 1.1.1 ID represents the resource ID of the menu option,

1.1.2 Tittle setting menu item title

1.1.3 Android:icon Setting menu item icon

1.1.4 android:checkable, sets whether the menu item is optional;

1.1.5 android:checked, sets whether the menu item is selected

1.1.5android:visibale set menu item whether courseware;

1.2 <group> elements for creating a set of menu items to use when creating a submenu, Common properties

Android:checkablebehavior sets whether a submenu item belongs to a single or multiple selection, and the value can be "single" and so on.

1.3 Developing a basic path

1.3.1 Create an XML file, make a new androidsourcedirection, Name menu, and create a good XML file,

1.3.2 overrides the activity's Oncreateoptionsmenu () or Oncreatecontentmenu () method and constructs the menu through XML in the method through the Getmenuinflater (). Inflate () method. ，

1.3.3 overrides the Onoptionselected () method or the Oncontentitemselected () method for the corresponding event.

1.4 Code

　　　　　　

<?xml version= "1.0" encoding= "Utf-8"?>
<menu xmlns:android= "Http://schemas.android.com/apk/res/android" >
    <item android:id = "@+id/menuid1"
    Android:title = "Test 1"/>
    <item android:id = "@+id/menuid2"
        Android:title = "Test 1"/>
</menu>

public class Mainactivity extends Appcompatactivity {
Button btn;

@Override
protected void OnCreate (Bundle savedinstancestate) {
Super.oncreate (savedinstancestate);
Setcontentview (R.layout.activity_main);
BTN = (Button) Findviewbyid (R.id.button);
Registerforcontextmenu (BTN);
}

@Override
public void Oncreatecontextmenu (ContextMenu menu, View V, contextmenu.contextmenuinfo menuinfo) {

Menuinflater inflator=new Menuinflater (this); Instantiate a Menuinflater object
Inflator.inflate (R.menu.testmenu, menu); Add the menu resource corresponding to the XML
Menu.setheadericon (R.drawable.color); Setting the context menu icon
Menu.setheadertitle ("Please select the background color"); Set context menu Title
}
@Override
public boolean oncontextitemselected (MenuItem item) {
return super.oncontextitemselected (item);
Switch (Item.getitemid ()) {
Case 0:
Toast.maketext (This, "context menu Test", Toast.length_short). Show ();
Break
Case 1:
Toast.maketext (This, "context menu Test 1", Toast.length_short). Show ();
Break
Case 2:
Toast.maketext (This, "context menu Test 2", Toast.length_short). Show ();
Break
Default
Break
}
return true;
}
}

Android Menu Easy to create