Android 2.2 Released

Google released version 2.2 of the Android SDK.<br />thi version has an API level equals to 8<br /><br />some of the new features:<br /><ol><li>Using Dalvik JIT (just in time) compiler which produces faster performance.</li><li>the ability to store applications on SD card instead on phone memory as in previous versions.</li><li>Application Backup API, enabling to store a backup of any application and use it on other phones.</li><li>The browser java script rendering has became faster.</li></ol>for more info you can check this link <a href="http://developer.android.com/sdk/android-2.2.html">http://developer.android.com/sdk/android-2.2.html</a><br /><br />or watch this video<br /><object height="385" width="640"><param name="movie" value="http://www.youtube.com/v/yAZYSVr2Bhc&hl=en_US&fs=1&"></param><param name="allowFullScreen" value="true"></param><param name="allowscriptaccess" value="always"></param><embed src="http://www.youtube.com/v/yAZYSVr2Bhc&hl=en_US&fs=1&" type="application/x-shockwave-flash" allowscriptaccess="always" allowfullscreen="true" width="640" height="385"></embed></object>

Google released version 2.2 of the Android SDK. thi version has an API level equals to 8 some of the new features: Using Dalvik JIT (just in...

Android Menus part 4: Alternative menus

<div dir="ltr" style="text-align: left;" trbidi="on">Android offers a third type of menus: Alternative menus which allow multiple applications to use each other. An application menu can contain menu items that point to other applications that deal with a certain data type that is passed from the application by an intent.<br /><br />This functionality is related to the concept of <strong>Content Providers</strong> which is in brief the ability of an application to expose its data (stored in a database or a file) by defining a <strong>MIME type</strong> to it and through a content <strong>URI</strong> to be accessed by any other application through this URI.<br /><br />For example if an application name <strong>Employees</strong> has some data of employees stored within this application context, and another application wants to access this data; then <strong>Employees</strong> application should declare a content provider  to expose its data, with a <strong>MIME type</strong>:<br /><br /><strong>vnd.android.cursor.item/mina.android.Employees</strong> so any other application can access the employees data by calling the Uri <strong>content://employees/All</strong> to access all employees or the Uri <strong>content://employees/1</strong> to access a single employee instance (for example).<br /><br />Back to our Alternative menus issue, suppose this Scenario: We have two applications:<br /><ol><li><strong>Application A</strong>: deals with the employees data.</li><li><strong>Application B</strong>: receives the content Uri of the employees and do some calculations on it.</li></ol>Now we want to add an alternative menu item in an activity in <strong>Application A</strong> so that when clicked passes a <strong>URI</strong> of employees and launches an activity in <strong>Application B</strong> (that manipulates the employees data according to the URI received).<br /><br />So to add the alternative menu item in the activity of <strong>Application A</strong>, we write the following in <strong>onCreateOptionsMenu </strong>method:<br /><pre class="brush:java">public boolean onCreateOptionsMenu(Menu menu) {<br /><br /> //adds a regular menu item<br /> menu.add("Regular item");<br /> //create the intent with the Uri of the employees content provider<br /> Intent targetIntent=<br /> new Intent(Intent.ACTION_VIEW, Uri.parse("content://employees/All"));<br /> targetIntent.addCategory(Intent.CATEGORY_ALTERNATIVE);<br /> menu.addIntentOptions(Menu.CATEGORY_ALTERNATIVE, //item group<br /> Menu.CATEGORY_ALTERNATIVE, //item id<br /> Menu.CATEGORY_ALTERNATIVE, //item order<br /> this.getComponentName(), //our activity class name<br /> null, //no specific menu items required<br /> targetIntent, // the intent to handle<br /> 0, //no flags<br /> null); //Optional array in which to place the menu<br />//items that were generated for each of<br />//the specifics that were requested<br /><br /> return true;<br /> }</pre>Here's what we did:<br /><ul><li>Create an intent with the desired action (<strong>Intent.ACTION_VIEW</strong>) on the specified content provider Uri (content://employees/All).</li><li>Call <strong>addIntentOptions</strong> method with the specified parameters.</li></ul>The above code adds a menu item that launches all possible activities in all applications on the device that can deal with the action <strong>Intent.ACTION_VIEW </strong>on the Uri content://employees/All.<br /><br />Now in<strong> Application B</strong>, if we want it to handle such an intent we have to do the following.<br /><br />Define an <strong>activity</strong> in the application and specify in the <strong>AndroidManifest.xml</strong> file that this activity can handle the requests of the employees content provider like this:<br /><pre class="brush:xml"><activity android:name=".ContentProvidersDemo" android:label="@string/app_name"><br /><br /> <intent-filter android:label="Access Employees"><br /> <action android:name="android.intent.action.VIEW" /><br /> <category android:name="android.intent.category.DEFAULT" /><br /> <category android:name="android.intent.category.ALTERNATIVE" /><br /> <data android:mimeType="vnd.android.cursor.item/mina.android.Employees" /><br /> </intent-filter><br /> </activity></pre>The above <strong>IntentFilter</strong> means that this activity will respond t0 any implicit intent from any application with the following parameters:<br /><ol><li><strong>Action</strong>: Intent.ACTION_VIEW.</li><li><strong>Category</strong>: android.intent.category.ALTERNATIVE.</li><li><strong>Data of MIME type</strong>:vnd.android.cursor.item/mina.android.Employees.</li></ol>So in <strong>Application A</strong> when you press on the menu button, you'll see a menu like this:<br /><br /><br /><br />When you press on the <strong>Access Employees</strong> menu item, the activity in <strong>Application B</strong> will be launched.<br /><div class="separator" style="clear: both; text-align: center;"><a href="http://dl.dropbox.com/u/2624328/Android%20Pro/2010/May/Menus2/alternative.png" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="150" src="http://dl.dropbox.com/u/2624328/Android%20Pro/2010/May/Menus2/alternative.png" width="320" /></a></div><br /><br /></div>

Android offers a third type of menus: Alternative menus which allow multiple applications to use each other. An application menu can contain...

Android Menus: part 3: Context Menus

In  previous posts we explored two types of android menus: Options menu and submenus. In this post we’re going to see another menu type: <strong>Context menus.</strong><br /><br /><span style="font-size: large;">Context Menu:</span><br /><br /><br />Context menus are the menus that appear when you right-click in windows.<br />In android Context menu are attached to widgets and the appear when you click on the widget for a long time (long click).<br /><br />To add context menus to widgets you have to do two things:<br /><ol><li>Register the widget for a context menu.</li><li>Add menu items to the context menu.</li></ol>So to register a context menu with a <strong>TextView</strong> you do it like this:<br /><pre class="brush:java">@Override<br /> public void onCreate(Bundle savedInstanceState) {<br /> super.onCreate(savedInstanceState);<br /> setContentView(R.layout.main);<br /> txt=(TextView)findViewById(R.id.txt);<br /> registerForContextMenu(txt);<br /> }<br /><br /></pre>We call <b>registerForContextMenu(View V)</b> method to tell the activity that the view is going to have a context menu.<br /><br />Then we add items to the context menu by overriding the onCreateContext method:<br /><pre class="brush:java">@Override<br /> public void onCreateContextMenu(ContextMenu menu,View v,ContextMenuInfo info)<br /> {<br /> menu.setHeaderTitle("Context Menu");<br /> menu.add("Item");<br /> }<br /><br /></pre>When you make a long click on the text view the context menu will appear like this:<br /><br /><div class="separator" style="clear: both; text-align: center;"><a href="http://dl.dropbox.com/u/2624328/Android%20Pro/2010/May/Menus3/menus6.JPG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" hw="true" src="http://dl.dropbox.com/u/2624328/Android%20Pro/2010/May/Menus3/menus6.JPG" width="226" /></a></div><br />The <b>onCreateContextMenu</b> method has the following parameters:<br /><ol><li><strong>Context Menu:</strong> an instance of the context menu.</li><li><strong>View:</strong> the view to which the context menu is attached.</li><li><strong>ContextMenuInfo:</strong> carries additional information regarding the creation of the context menu.</li></ol>To handle the context menu items click events you can implement the callback method <strong>onContextItemSelected.</strong><br />We do it the same way we handle <strong>onOptionsItemSelected</strong>.<br /><pre class="brush:java">@Override<br /> public boolean onContextItemSelected(MenuItem item)<br /> {<br /> txt.setText(item.getTitle());<br /> return true;<br /> }<br /><br /></pre>

In  previous posts we explored two types of android menus: Options menu and submenus. In this post we’re going to see another menu type: Con...

Android Menus: part 2: Handling Menu Items Events

We can handle menu items events by three ways:<br /><ol><li>By implementing <strong>onOptionsItemSelected</strong> method.</li><li>By implementing listeners to single menu items.</li><li>By using intents.</li></ol><span style="font-size: large;">Using onOptionsItemSelected method:</span><br />Implement the <strong>onOptionsItemSelected</strong> method like this:<br /><pre class="brush:java">@Override<br /> public boolean onOptionsItemSelected(MenuItem item)<br /> {<br /> TextView txt=(TextView)findViewById(R.id.txt);<br /> txt.setText("you clicked on item "+item.getTitle());<br /> return true;<br /> }<br /><br /></pre>Notice that it returns a <strong>Boolean</strong> which should be true to execute the method, if false it will not execute.<br /><br />You can switch between the menu items like this:<br /><pre class="brsh:java">@Override<br /> public boolean onOptionsItemSelected(MenuItem item)<br /> {<br /> TextView txt=(TextView)findViewById(R.id.txt);<br /> switch(item.getItemId())<br /> {<br /> case 1:<br /> txt.setText("you clicked on item "+item.getTitle());<br /> return true;<br /> case 2:<br /> txt.setText("you clicked on item "+item.getTitle());<br /> return true;<br /> case 3:<br /> txt.setText("you clicked on item "+item.getTitle());<br /> return true;<br /> <br /> <br /> }<br /> return super.onOptionsItemSelected(item);<br /> <br /> }<br /><br /></pre><br />Notice that we return true for every handled menu item. And for un handled menu items (outside switch block) we call the super class method.<br /><br /><span style="font-size: large;">Using listners:</span><br /><br />We can handle options menu items click events by making the activity implement <strong>onMenuItemClickListner</strong> interface provide an implementation of <strong>onMenuItemClick</strong> method like this:<br /><pre class="brush:java">public class MenusDemo extends Activity implements OnMenuItemClickListener<br /></pre>then implement the method:<br /><pre class="brush:java">public boolean onMenuItemClick(MenuItem item) {<br /> TextView txt=(TextView)findViewById(R.id.txt);<br /> txt.append("listner");<br /> return false;<br /> }<br /><br /></pre><br />Notice that the method returns a <strong>Boolean</strong>. If it returns true no other callbacks will be executed. If returns false then <strong>onOptionsItemSelected</strong> callback will be executed directly after this callback.<br /><br /><span style="font-size: large;">Using intents:</span><br />You can specify an intent to be launched when an options menu item is clicked like this:<br /><pre class="brush:java">menu.add(1, “dialItem”, 1, "Dial").setIcon(R.drawable.dvd).setIntent(new Intent(Intent.ACTION_DIAL));<br /></pre><br />note that if you specify an intent for an item and at the same time override the <b>onOptionsItemSelected</b> method and handle the selection for that item, the precedence of execution is to the code in the onOptionsItemSelected.<br />meaning that the code in <b>onOptionsItemSelected</b> method will be executed first, if it returns true then the intent will not be launched, if returns false then the intent will launch.<br /><br />So if you want to use intent for menu items don’t handle it in <b>onOptionsItemSelected</b> method but invoke the parent <b>onOptionsItemSelected</b>.<br /><br /><b>Scenario 1:</b><br /><pre class="brush:java">@Override<br /> public boolean onCreateOptionsMenu(Menu menu)<br /> {<br /> menu.add(1, “dialItem”, 1, "Dial").setIcon(R.drawable.dvd).setIntent(new Intent(Intent.ACTION_DIAL)); return super.onCreateOptionsMenu(menu);<br /> <br /> }<br /><br />@Override<br /> public boolean onOptionsItemSelected(MenuItem item)<br /> {<br /> TextView txt=(TextView)findViewById(R.id.txt);<br /> switch(item.getItemId())<br /> {<br /> case 1:<br /> txt.append("you clicked on item "+item.getTitle());<br /> return true;<br /> case “dialItem”:<br /> txt.setText("you clicked on item "+item.getTitle());<br /> return true;<br /> case 3:<br /> txt.setText("you clicked on item "+item.getTitle());<br /> return true;<br /> <br /> <br /> }<br /> return super.onOptionsItemSelected(item);<br /> <br /> }<br /><br /><br /></pre>This will execute the code of the onOptionsItemSelected method and the dialer intent will not be launched.<br /><br /><b>Scenario 2:</b><br /><br /><pre class="brush:java">@Override<br /> public boolean onCreateOptionsMenu(Menu menu)<br /> {<br /> menu.add(1, “dialItem”, 1, "Dial").setIcon(R.drawable.dvd).setIntent(new Intent(Intent.ACTION_DIAL)); return super.onCreateOptionsMenu(menu);<br /> <br /> }<br /><br />@Override<br /> public boolean onOptionsItemSelected(MenuItem item)<br /> {<br /> TextView txt=(TextView)findViewById(R.id.txt);<br /> switch(item.getItemId())<br /> {<br /> case 1:<br /> txt.append("you clicked on item "+item.getTitle());<br /> return true;<br /> case “dialItem”:<br /> txt.setText("you clicked on item "+item.getTitle());<br /> return false;<br /> case 3:<br /> txt.setText("you clicked on item "+item.getTitle());<br /> return true;<br /> <br /> <br /> }<br /> return super.onOptionsItemSelected(item);<br /> <br /> }<br />This will execute the code of the onOptionsItemSelected method and then dialer intent will be launched.<br /><br /></pre><br /><b>Scenario 3:</b><br /><br /><pre class="brush:java">@Override<br /> public boolean onCreateOptionsMenu(Menu menu)<br /> {<br /> menu.add(1, “dialItem”, 1, "Dial").setIcon(R.drawable.dvd).setIntent(new Intent(Intent.ACTION_DIAL)); return super.onCreateOptionsMenu(menu);<br /> <br /> }<br /><br />@Override<br /> public boolean onOptionsItemSelected(MenuItem item)<br /> {<br /> TextView txt=(TextView)findViewById(R.id.txt);<br /> switch(item.getItemId())<br /> {<br /> case 1:<br /> txt.append("you clicked on item "+item.getTitle());<br /> return true;<br /> <br /> case 3:<br /> txt.setText("you clicked on item "+item.getTitle());<br /> return true;<br /> <br /> <br /> }<br /> return super.onOptionsItemSelected(item);<br /> <br /> }<br /><br /><br /></pre><br />the onOptionsItemSelected does not handle the "<b>dialerItem</b>" selection, so The dialer intent will be launched directly.

We can handle menu items events by three ways: By implementing onOptionsItemSelected method. By implementing listeners to single menu items...

Android Menus: Part 1: Options menu and sub menus

Android phones have the menu button which displays a menu with several items that provide navigation or more functionality or settings to your applications<br /><br /><div></div>Android has three types of menus<br />1. Options Menu<br />2. Context Menu<br />3. Sub menus<br /><br /><div></div>Menu items can be grouped and each menu item can have submenu items.<br /><br /><div></div><span style="font-size: large;">Options Menu</span><br /><br /><div></div>Each activity has a single menu. It appears when you press the menu button Each activity creates this menu in the callback method <strong>onCreateOptionsMenu</strong> you can override this method and add items to the menu.<br />If you press the menu button you will see the menu like this:<br /><pre class="brush:java">public class MenusDemo extends Activity {<br /> /** Called when the activity is first created. */<br /> @Override<br /> public void onCreate(Bundle savedInstanceState) {<br /> super.onCreate(savedInstanceState);<br /> setContentView(R.layout.main);<br /> }<br /> <br /> @Override<br /> public boolean onCreateOptionsMenu(Menu menu)<br /> {<br /> menu.add("Item1");<br /> menu.add("Item2");<br /> return true;<br /> }<br />}<br /><br /></pre><br /><div></div><div class="separator" style="clear: both; text-align: center;"><a href="http://dl.dropbox.com/u/2624328/Android%20Pro/2010/May/Menus%201/menus1.JPG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" ru="true" src="http://dl.dropbox.com/u/2624328/Android%20Pro/2010/May/Menus%201/menus1.JPG" width="228" /></a></div><br /><div></div>Notice that the <strong>onCreateOptionsMenu</strong> method returns a Boolean. It should return true for the menu to appear, if returns false the menu will be invisible.<br /><br /><div></div>If you add many menu items, more than five items they will appear like this:<br /><pre class="brush:java">public boolean onCreateOptionsMenu(Menu menu)<br /> {<br /> menu.add(1, 1, 0, "Item1");<br /> menu.add(1, 2, 1, "Item2");<br /> menu.add(1, 3, 2, "Item3");<br /> menu.add(1, 4, 3, "Item4");<br /> menu.add(1, 5, 4, "Item5");<br /> <br /> menu.add(2, 6, 0, "Item6");<br /> menu.add(2, 7, 1, "Item7");<br /> menu.add(2, 8, 2, "Item8");<br /> menu.add(2, 9, 3, "Item9");<br /> menu.add(2, 10, 4, "Item10");<br /> <br /> <br /> <br /> return true;<br /> }<br /><br /></pre><br /><div></div><div class="separator" style="clear: both; text-align: center;"><a href="http://dl.dropbox.com/u/2624328/Android%20Pro/2010/May/Menus%201/menus2.JPG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" ru="true" src="http://dl.dropbox.com/u/2624328/Android%20Pro/2010/May/Menus%201/menus2.JPG" width="226" /></a></div><br /><div></div>When you press on the “<strong>more</strong>” link you will see the rest of the menu items<br /><br /><div class="separator" style="clear: both; text-align: center;"><a href="http://dl.dropbox.com/u/2624328/Android%20Pro/2010/May/Menus%201/menu22.JPG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" ru="true" src="http://dl.dropbox.com/u/2624328/Android%20Pro/2010/May/Menus%201/menu22.JPG" width="226" /></a></div><br /><br />The<strong> menu.add(int GroupID,int ItemID,int Order,String Title)</strong> method has the following parameters:<br /><ol><li><strong>GroupID</strong>: used to group related menu items to apply some configurations on all items of a certain group once at a time (discussed later) .</li><li><strong>ItemID</strong>: an integer to identify the menu item.</li><li><strong>Order</strong>: the sort order or the order ID, controls the order of menu items in a menu. Items with lower order id appear first. There are some constants defined for sort order for different kinds of menu items<br />Like Menu.CATEGORY_SECONDRY for secondry menu items, Menu.CATEGORY_SYSTEM for system menu items and Menu.CATEGORY_ALTERNATIVE for altenative menu items..</li><li><strong>Title</strong>: the text of the menu item</li></ol><br /><br />We could have written the previous code using the predefined the sort order constants like this:<br /><pre class="brush:java">menu.add(1, 1, Menu.FIRST, "Item1");<br /> menu.add(1, 2, Menu.FIRST+1, "Item2");<br /> menu.add(1, 3, Menu.FIRST+2, "Item3");<br /> menu.add(1, 4, Menu.FIRST+3, "Item4");<br /> menu.add(1, 5, Menu.FIRST+4, "Item5");<br /> <br /> menu.add(2, 6, Menu.CATEGORY_SECONDARY, "Item1");<br /> menu.add(2, 7, Menu.CATEGORY_SECONDARY+1, "Item2");<br /> menu.add(2, 8, Menu.CATEGORY_SECONDARY+2, "Item3");<br /> menu.add(2, 9, Menu.CATEGORY_SECONDARY+3, "Item4");<br /> menu.add(2, 10, Menu.CATEGORY_SECONDARY+4, "Item5");<br /><br /><br /></pre><br /><br /><strong>Adding Icons to menu items:</strong><br />We saw that only the first five items can appear in the options menu and the other items appear in a dialog when you press “<strong>more</strong>” item.<br />For the first five items you can add an icon to appear next to the item's title:<br /><pre class="brush:java">menu.add(1, 1, 0, "Blu-Ray").setIcon(R.drawable.bluray);<br /> menu.add(1, 2, 1, "DVD").setIcon(R.drawable.dvd);<br /> menu.add(1, 3, 2, "Hard Disk").setIcon(R.drawable.hd);<br /> menu.add(1, 4, 3, "Sites").setIcon(R.drawable.sites);<br /> menu.add(1, 5, 4, "USB").setIcon(R.drawable.usb);<br /> <br /> menu.add(2, 6, 5, "Item1");<br /> menu.add(2, 7, 6, "Item2");<br /> menu.add(2, 8, 7, "Item3");<br /> menu.add(2, 9, 8, "Item4");<br /> menu.add(2, 10, 9, "Item5");<br /><br /></pre><br /><div class="separator" style="clear: both; text-align: center;"><a href="http://dl.dropbox.com/u/2624328/Android%20Pro/2010/May/Menus%201/menus3.JPG" imageanchor="1" style="margin-left: 1em; margin-right: 1em;"><img border="0" height="320" ru="true" src="http://dl.dropbox.com/u/2624328/Android%20Pro/2010/May/Menus%201/menus3.JPG" width="226" /></a></div><br /><strong>Grouping Menu Items:</strong><br /><br />We saw that the method we use to add menu items us Menu.Add(GroupID,ItemId,OrderID,Title)<br />The first parameter is GroupID, what is it ? the answer leads us to grouping Menu Items.<br /><br />Grouping menu items makes it easy to apply some options on some related menu items by applying these options on all menu items that belong to a group once instead of applying them on each single item at a time.<br /><br />The actions that can be applied on a group can be:<br /><ul><li><strong>Menu.removeGroup(int GroupID)</strong>: to remove all menu items belonging to the same group.</li><li><strong>Menu.setGroupCheckable(int GroupID,Boolean Checakble,Boolean Exclusive)</strong>: maked a group appear with a check mark beside each item. If the Boolean Exclusive is set to true then the items will appear as if they are in a radiobuttongroup and only one item can be selected at a time. If set to false then they will appear with check boxes beside each item and multiple items can be selected at a time.</li><li><strong>Menu.setGroupEnabled(int GroupID,Boolean Enabled)</strong>: sets all items in a group to be enabled/disabled.</li><li><strong>Menu.setGroupVisible(int GroupID,Boolean Visible)</strong>: sets all items in a group to be visible/invisible.</li></ul><strong>Note</strong>: the methods mentioned above can be applied only to menu items in the secondary menu (items that appear when you click the more button)<br /><br /><br /><span style="font-size: large;">Adding Alpha-Numeric shortcuts to menu Items:</span><br />You can add alphabetic or numeric shortcuts to menu items like this:<br /><pre class="brush:java">menu.add(2, 8, 7, "Item3").setNumericShortcut('3');<br />menu.add(2, 9, 8, "Item4").setAlphabeticShortcut('c');<br /></pre>then setting the querty mode of the menu to true like this:<br /><pre class="brush:java">menu.setQwertyMode(true);<br /></pre><br />and that's it for Android's options menu.<br /><br />In a next post we'll talk about handling options menu events

Android phones have the menu button which displays a menu with several items that provide navigation or more functionality or settings to yo...