day01- Upper- Dialog interfaces
public class
implements DialogInterface Window.Callback KeyEvent.Callback View.OnCreateContextMenuListener
Dialog
extends Objectimplements DialogInterface Window.Callback KeyEvent.Callback View.OnCreateContextMenuListener
| java.lang.Object | |
| ↳ | android.app.Dialog |
|
AlertDialog,
AppCompatDialog,
CharacterPickerDialog,
MediaRouteChooserDialog,
Presentation
|
|
AlertDialog,
DatePickerDialog,
MediaRouteControllerDialog,
ProgressDialog,
TimePickerDialog
|
we all know every class are extends Object, It's nothing special.
so, the problem is what is Window.Callback ,
KeyEvent.Callback ,
View.OnCreateContextMenuListener
first . Window.Callback
public static interface
Window.Callback
| android.view.Window.Callback |
|
AccountAuthenticatorActivity,
ActionBarActivity,
Activity,
ActivityGroup,
AlertDialog,
AliasActivity,
AppCompatActivity,
AppCompatDialog, CharacterPickerDialog,
DatePickerDialog,
Dialog, and
9 others.
|
Class Overview
API from a Window back to its caller. This allows the client to intercept key dispatching, panels and menus, etc.
from view.Window.Callback , with so many Activity. almost include main content View.Like AppCompatActivity, Diaolg, Activity. God ! It's so important but I can not believe I never touch this place.
Here some methods. Let's check.
|
abstract boolean
|
dispatchKeyEvent( KeyEvent
event)
Called to process key events.
|
|
abstract boolean
|
dispatchTouchEvent( MotionEvent
event)
Called to process touch screen events.
|
|
abstract void
|
onContentChanged()
This hook is called whenever the content view of the screen changes (due to a call to
Window.setContentView
or
Window.addContentView).
|
|
abstract boolean
|
onMenuItemSelected(int featureId,
MenuItem
item)
Called when a panel's menu item has been selected by the user.
|
|
abstract void
|
onWindowAttributesChanged( WindowManager.LayoutParams
attrs)
This is called whenever the current window attributes change.
|
|
abstract void
|
onWindowFocusChanged(boolean hasFocus)
This hook is called whenever the window focus changes.
|
Oh !!! that's a big trasher,Look,
dispatchKeyEvent
( KeyEvent
event), I can got everything about Screen.It's my place, and onContentChanged(), this hook is called whenever the content view of the screen changes (due to a call to
Window.setContentView or Window.addContentView ). I got U. Window.Callback is like a part of our body. like ears or eyes.
second . KeyEvent.Callback
public static interface
KeyEvent.Callback
| android.view.KeyEvent.Callback |
|
AbsListView,
AbsSeekBar,
AbsSpinner,
AbsoluteLayout,
AbstractInputMethodService,
AccountAuthenticatorActivity,
ActionBarActivity, ActionMenuView,
Activity, and
142 others.
|
Summary
| Public Methods | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
abstract boolean
|
onKeyDown(int keyCode,
KeyEvent
event)
Called when a key down event has occurred.
|
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|
abstract boolean
|
onKeyLongPress(int keyCode,
KeyEvent
event)
Called when a long press has occurred.
|
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|
abstract boolean
|
onKeyMultiple(int keyCode, int count,
KeyEvent
event)
Called when multiple down/up pairs of the same key have occurred in a row.
|
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|
abstract boolean
|
onKeyUp(int keyCode,
KeyEvent
event)
Called when a key up event has occurred.
|
||||||||||
no more words, I think I got u. scratch
Input information.
third . View.OnCreateContextMenuListener
public static interface
View.OnCreateContextMenuListener
| android.view.View.OnCreateContextMenuListener |
|
AccountAuthenticatorActivity,
ActionBarActivity,
Activity,
ActivityGroup,
AlertDialog,
AliasActivity,
AppCompatActivity,
AppCompatDialog, AppCompatDialogFragment,
BaseLeanbackPreferenceFragment,
BrowseFragment,
BrowseSupportFragment, and
50 others.
|
Class Overview
Interface definition for a callback to be invoked when the context menu for this view is being built.
Summary
| Public Methods | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
|
abstract void
|
onCreateContextMenu( ContextMenu
menu,
View
v,
ContextMenu.ContextMenuInfo
menuInfo)
Called when the context menu for this view is being built.
|
||||||||||
Um, what ? onCreate, context, Menu, Listener ? mix them make me pozzle. a callback to be invoked when the context
menu for thie view is being built
?
doesn't matter. keep go on....
Called when the context menu for this view is being built. It is not safe to hold onto the menu after this method returns.
Parameters
| menu | The context menu that is being built |
|---|---|
| v | The view for which the context menu is being built |
| menuInfo | Extra information about the item for which the context menu should be shown. This information will vary depending on the class of v. |
not safe. I got a doubt. why context need menu? if context is bascial element like object.It's should blanket. no menus.
I need to know how to work like Window.Callback and KeyEvent.Callback
, also I need to know why context need menus?
I'll do this tomorrow night. It's 2016-1-18 23:28:04 . I should go bed for my work tomorrow. It's the first I write blog in English.Feel like good.
I'm fish, I'm on.
----jack chen