Menu Xml 使用
Menu Xml 使用
Menu resource
A menu resource defines an application menu (Options Menu, Context Menu, or submenu) that can be inflated with MenuInflater.
For a guide to using menus, see the Menus developer guide.
file location:
res/menu/filename.xml
The filename will be used as the resource ID.
compiled resource datatype:
Resource pointer to a Menu (or subclass) resource.
resource reference:
In Java: R.menu.filename
In XML: @[package:]menu.filename
syntax:
<？xml version =“1.0”encoding =“utf-8”？>
< menu xmlns：android =“http://schemas.android.com/apk/res/android”>
< item android：id =“@ [+] [ package：] id / resource_name ”
android：title =“ string ”
android：titleCondensed =“ string ”
android：icon =“@ [package：] drawable / drawable_resource_name ”
android：onClick =“ 方法名称 ”
android：showAsAction = [“ifRoom”| “从不”| “withText”| “永远”| “collapseActionView”]
android：actionLayout =“@ [package：] layout / layout_resource_name ”
android：actionViewClass =“ 类名 ”
android：actionProviderClass =“ 类名 ”
android：alphabeticShortcut =“ string ”
android：alphabeticModifiers = [“META”| “CTRL”| “ALT”| “SHIFT”| “SYM”| “功能”]
android：numericShortcut =“ string ”
android：numericModifiers = [“META”| “CTRL”| “ALT”| “SHIFT”| “SYM”| “功能”]
android：checkable = [“true”| “假”]
android：visible = [“true”| “假”]
android：enabled = [“true”| “假”]
android：menuCategory = [“container”| “系统”| “二级”| “替代”]
android：orderInCategory =“ integer ”/>
< group android：id =“@ [+] [ package：] id / resource name ”
android：checkableBehavior = [“none”| “所有”| “单”]
android：visible = [“true”| “假”]
android：enabled = [“true”| “假”]
android：menuCategory = [“container”| “系统”| “二级”| “替代”]
android：orderInCategory =“ integer ”>
< item />
< item >
< menu >
< item />
elements:
Required. This must be the root node. Contains and/or elements. attributes:xmlns:android
XML namespace. Required. Defines the XML namespace, which must be “http://schemas.android.com/apk/res/android”.
A menu item. May contain a
attributes:
android:id
Resource ID. A unique resource ID. To create a new resource ID for this item, use the form: “@+id/name”. The plus symbol indicates that this should be created as a new ID.
android:title
String resource. The menu title as a string resource or raw string.
android:titleCondensed
String resource. A condensed title as a string resource or a raw string. This title is used for situations in which the normal title is too long.
android:icon
Drawable resource. An image to be used as the menu item icon.
android:onClick
Method name. The method to call when this menu item is clicked. The method must be declared in the activity as public and accept a MenuItem as its only parameter, which indicates the item clicked. This method takes precedence over the standard callback to onOptionsItemSelected(). See the example at the bottom.
Warning: If you obfuscate your code using ProGuard (or a similar tool), be sure to exclude the method you specify in this attribute from renaming, because it can break the functionality.
Introduced in API Level 11.
android:showAsAction
Keyword. When and how this item should appear as an action item in the app bar. A menu item can appear as an action item only when the activity includes an app bar. Valid values:
Value Description
ifRoom Only place this item in the app bar if there is room for it. If there is not room for all the items marked “ifRoom”, the items with the lowest orderInCategory values are displayed as actions, and the remaining items are displayed in the overflow menu.
withText Also include the title text (defined by android:title) with the action item. You can include this value along with one of the others as a flag set, by separating them with a pipe |.
never Never place this item in the app bar. Instead, list the item in the app bar’s overflow menu.
always Always place this item in the app bar. Avoid using this unless it’s critical that the item always appear in the action bar. Setting multiple items to always appear as action items can result in them overlapping with other UI in the app bar.
collapseActionView The action view associated with this action item (as declared by android:actionLayout or android:actionViewClass) is collapsible.
Introduced in API Level 14.
See the Adding the App Bar training class for more information.
Introduced in API Level 11.
android:actionLayout
Layout resource. A layout to use as the action view.
See Action Views and Action Providers for more information.
Introduced in API Level 11.
android:actionViewClass
Class name. A fully-qualified class name for the View to use as the action view. For example, “android.widget.SearchView” to use SearchView as an action view.
See Action Views and Action Providers for more information.
Warning: If you obfuscate your code using ProGuard (or a similar tool), be sure to exclude the class you specify in this attribute from renaming, because it can break the functionality.
Introduced in API Level 11.
android:actionProviderClass
Class name. A fully-qualified class name for the ActionProvider to use in place of the action item. For example, “android.widget.ShareActionProvider” to use ShareActionProvider.
See Action Views and Action Providers for more information.
Warning: If you obfuscate your code using ProGuard (or a similar tool), be sure to exclude the class you specify in this attribute from renaming, because it can break the functionality.
Introduced in API Level 14.
android:alphabeticShortcut
Char. A character for the alphabetic shortcut key.
android:numericShortcut
Integer. A number for the numeric shortcut key.
android:alphabeticModifiers
Keyword. A modifier for the menu item’s alphabetic shortcut. The default value corresponds to the Control key. Valid values:
Value Description
META Corresponds to the Meta meta key
CTRL Corresponds to the Control meta key
ALT Corresponds to the Alt meta key
SHIFT Corresponds to the Shift meta key
SYM Corresponds to the Sym meta key
FUNCTION Corresponds to the Function meta key
Note: You can specify multiple keywords in an attribute. For example, android:alphabeticModifiers=“CTRL|SHIFT” indicates that to trigger the corresponding menu item, the user needs to press both Control and Shift meta keys along with the shortcut.
You can use the setAlphabeticShortcut() method to set the attribute values programmatically. For more information about the alphabeticModifier attribute, go to alphabeticModifiers.
android:numericModifiers
Keyword. A modifier for the menu item’s numeric shortcut. The default value corresponds to the Control key. Valid values:
Value Description
META Corresponds to the Meta meta key
CTRL Corresponds to the Control meta key
ALT Corresponds to the Alt meta key
SHIFT Corresponds to the Shift meta key
SYM Corresponds to the Sym meta key
FUNCTION Corresponds to the Function meta key
Note: You can specify multiple keywords in an attribute. For example, android:numericModifiers=“CTRL|SHIFT” indicates that to trigger the corresponding menu item, the user needs to press both Control and Shift meta keys along with the shortcut.
You can use the setNumericShortcut() method to set the attribute values programmatically. For more information about the numericModifier attribute, go to numericModifiers.
android:checkable
Boolean. “true” if the item is checkable.
android:checked
Boolean. “true” if the item is checked by default.
android:visible
Boolean. “true” if the item is visible by default.
android:enabled
Boolean. “true” if the item is enabled by default.
android:menuCategory
Keyword. Value corresponding to Menu CATEGORY_* constants, which define the item’s priority. Valid values:
Value Description
container For items that are part of a container.
system For items that are provided by the system.
secondary For items that are user-supplied secondary (infrequently used) options.
alternative For items that are alternative actions on the data that is currently displayed.
android:orderInCategory
Integer. The order of “importance” of the item, within a group.
A menu group (to create a collection of items that share traits, such as whether they are visible, enabled, or checkable). Contains one or more elements. Must be a child of a
attributes:
android:id
Resource ID. A unique resource ID. To create a new resource ID for this item, use the form: “@+id/name”. The plus symbol indicates that this should be created as a new ID.
android:checkableBehavior
Keyword. The type of checkable behavior for the group. Valid values:
Value Description
none Not checkable
all All items can be checked (use checkboxes)
single Only one item can be checked (use radio buttons)
android:visible
Boolean. “true” if the group is visible.
android:enabled
Boolean. “true” if the group is enabled.
android:menuCategory
Keyword. Value corresponding to Menu CATEGORY_* constants, which define the group’s priority. Valid values:
Value Description
container For groups that are part of a container.
system For groups that are provided by the system.
secondary For groups that are user-supplied secondary (infrequently used) options.
alternative For groups that are alternative actions on the data that is currently displayed.
android:orderInCategory
Integer. The default order of the items within the category.
example:
XML file saved at res/menu/example_menu.xml:
The following application code inflates the menu from the onCreateOptionsMenu(Menu) callback and also declares the on-click callback for two of the items:
KOTLIN
JAVA
override fun onCreateOptionsMenu(menu: Menu): Boolean {
menuInflater.inflate(R.menu.example_menu, menu)
return true
}
fun onGroupItemClick(item: MenuItem) {
// One of the group items (using the onClick attribute) was clicked
// The item parameter passed here indicates which item it is
// All other menu item clicks are handled by onOptionsItemSelected()
}