[Android, 18] common components in android:

1. Use of the notification component:

1. The notification component displays a text message prompt in the phone taskbar when a short message is sent. When you click it, an activity is activated.

 

2. Create and use:

Public void click (Viewview ){

// 1 Get a reference to the icationicationmanager:

// Obtain the administrator of a notification.

Icationicationmanager manager = (NotificationManager) getSystemService (

NOTIFICATION_SERVICE );

 

// 2. initialize the notification to be displayed by the manager.

 

Int icon = R. drawable. ic_launcher;

CharSequence tickerText = "Hello title ";

Long when = System. currentTimeMillis ();

// Constructor parameters: (icon, title, and notification display time)

Icationicationnotification = new Notification (icon, tickerText, when );

 

// 3. Specific notification events

// Specify the sound

Notification. sound = Uri. fromFile (newFile ("/sdcard/hacard "));

Notification. ledARGB // What is the LED light displayed?

// The unit of the specified vibration time in milliseconds

Notification. vibrate (); // parameter long [] array 20 50 80

// Specify the display status of notification. (FLAG_NO_CLEAR: not displayed, FLAG_INSISTENT: always displayed)

Notification. flags = Notification. FLAG_NO_CLEAR;

 

// The intent of the extension

Intent intent = new Intent ();

Intent. setAction (Intent. ACTION_CALL );

Intent. setData (Uri. parse ("tel: 123456 "));

 

// Create extension intent getActivity method parameters (context, 0, intent object, 0)

PendingIntent contentIntent = PendingIntent. getActivity (this, 0, intent, 0 );

Set the extension intent for notification:

Notification. contentIntent = contentIntent;

 

// The setLatestEventInfo () method is to set the content opened by clicking notification and execute the extension intent.

Notification. setLatestEventInfo (this, "title", "body", contentIntent );

// 4. Use the notification manager to display the notification

Manager. Y (0, notification );

 

}

}

Ii. usage of the dialog box:

 

1. Confirm to cancel the dialog box:

Public void click1 (View view ){

// 1. Create a builder in the dialog box

AlertDialog. Builderbuilder = new Builder (this );

Builder. setIcon (R. drawable. ic_launcher );

Builder. setTitle ("I am the title ");

Builder. setMessage ("I am the body ");

// Confirmation button in the dialog box

Builder. setPositiveButton ("OK", newOnClickListener (){

 

@ Override

Public void onClick (DialogInterface dialog, int which ){

// TODO Auto-generatedmethod stub

System. out. println ("OK ");

}

});

// Set the cancel button and click event

Builder. setNegativeButton ("cancel", newOnClickListener (){

 

@ Override

Public void onClick (DialogInterface dialog, int which ){

// TODO Auto-generatedmethod stub

System. out. println ("canceled ");

}

});

// The create dialog box is displayed.

Builder. create (). show ();

}

2. Select dialog box

Public void click2 (View view ){

AlertDialog. Builder builder = new Builder (this );

Final String [] items = {"red", "blue", "green "};

// Set the data and click events in the select dialog box

Builder. setItems (items, new OnClickListener (){

 

Method parameters (currently dialog, the items to be clicked are in the items array subscript)

Public voidonClick (DialogInterface dialog, int which ){

Toast. makeText (getApplicationContext (),

Items [which] + "clicked ",

0). show ();

 

}

});

// Display dialog box

Builder. create (). show ();

}

3. Single-choice dialog box:

Public void click3 (View view ){

Final CharSequence [] items = {"Red", "Green", "Blue "};

 

AlertDialog. Builder builder = new AlertDialog. Builder (this );

Builder. setTitle ("Pick a color ");

// Method parameters (array, the default entry tag-1 is not selected by default, click the event)

Builder. setSingleChoiceItems (items,-1,

New DialogInterface. OnClickListener (){

Public voidonClick (DialogInterface dialog, int item ){

Toast. makeText (getApplicationContext (), items [item],

Toast. LENGTH_SHORT). show ();

// Close the dialog box

Dialog. dismiss ();

}

});

AlertDialog alert = builder. create ();

Alert. show ();

}

4. Multiple choice dialog box:

Public void click4 (View view ){

Final CharSequence [] items = {"Red", "Green", "Blue "};

 

AlertDialog. Builder builder = new AlertDialog. Builder (this );

Builder. setTitle ("Pick a color ");

// Method parameters: (array, default selected array. "true" indicates that the corresponding entry is selected. Click the event)

Builder. setMultiChoiceItems (items,

New boolean [] {false, true, false },

New OnMultiChoiceClickListener (){

 

@ Override

Public voidonClick (DialogInterface dialog, int which,

Boolean isChecked ){

 

Toast. makeText (getApplicationContext (),

Items [which] + "" + isChecked,

Toast. LENGTH_SHORT). show ();

}

});

// Set the confirmation button

Builder. setPositiveButton ("OK", newOnClickListener (){

 

@ Override

Public voidonClick (DialogInterface dialog, int which ){

// TODO Auto-generated method stub

 

}

});

 

AlertDialog alert = builder. create ();

Alert. show ();

}

 

5. progress bar dialog box: ProgressDialog class

Public void click5 (Viewview ){

ProgressDialog pd = new ProgressDialog (this );

Pd. setTitle ("prompt title ");

Pd. setMessage ("processing ...");

Pd. show ();

}

 

Iii. drop-down list Components

1. Components in the drop-down list:

Android: id = "@ + id/spinner"

Android: layout_width = "fill_parent"

Android: layout_height = "wrap_content"/>

 

2. Operations in the drop-down list:

// Retrieve the drop-down list component

Spinner spinner = (Spinner) this. findViewById (R. id. spinner );

// Create an adapter

ArrayAdapter Adapter = newArrayAdapter (This,

Android. R. layout. simple_spinner_item );

// Set the layout for adaptation

// Android. R. layout. simple_spinner_dropdown_item

Adapter. setDropDownViewResource (android. R. layout. simple_spinner_dropdown_item );

Adapter. add ("java ");

Adapter. add ("dotNet ");

Adapter. add ("php ");

 

Spinner. setAdapter (adapter );

// Click an event

Spinner. setOnItemSelectedListener (new OnItemSelectedListener (){

 

@ Override

Public voidonItemSelected (AdapterView Parent, View view,

Int position, long id ){

// TODO Auto-generated method stub

 

}

 

@ Override

Public voidonNothingSelected (AdapterView Parent ){

// TODO Auto-generated method stub

 

}

});

 

4. Dragging:

1. Drag a widget:

Android: id = "@ + id/seekBar1"

Android: layout_width = "match_parent"

Android: layout_height = "wrap_content"/>

2. component usage:

// Drag the Component Object

SeekBar1 = (SeekBar) this. findViewById (R. id. seekBar1 );

 

SeekBar1.setMax (100); // you can specify the maximum size of a dragged bar.

SeekBar1.setProgress (50); // drag the current value of the bar

// Drag event

SeekBar1.setOnSeekBarChangeListener (new OnSeekBarChangeListener (){

 

// Method for stopping a drag

Public voidonStopTrackingTouch (SeekBar seekBar ){

// TODO Auto-generated method stub

System. out. println ("stopped dragging ");

// Obtain the current location

Int position = seekBar. getProgress ();

 

}

 

@ Override

// Method to start dragging:

Public voidonStartTrackingTouch (SeekBar seekBar ){

// TODO Auto-generated method stub

System. out. println ("started dragging ");

 

}

 

@ Override

Public voidonProgressChanged (SeekBar seekBar, int progress,

Boolean fromUser ){

// TODO Auto-generated method stub

 

}

});

 

5. Menu:

Override two methods in the activity class:

 

@ Override // set menu items

Public boolean onCreateOptionsMenu (Menu menu ){

Menu. add (Menu. NONE, 1, Menu. NONE, "add ");

Menu. add (Menu. NONE, 2, Menu. NONE, "Update ");

Return super. onCreateOptionsMenu (menu );

}

 

@ Override // click the menu item event

Public boolean onMenuItemSelected (int featureId, MenuItem item ){

Switch (item. getItemId ()){

Case 1: // Add

Log. I ("tag", "add was selected ");

Return true;

Case 2: // update

Log. I ("tag", "update was selected ");

Return true;

Default:

Returnsuper. onMenuItemSelected (featureId, item );

}

}

6. Enter the content to automatically complete the text box (AutoCompleteTextView)

1. Components

Android: layout_width = "fill_parent"

Android: layout_height = "wrap_content"

Android: completionThreshold = "1"

Android: id = "@ + id/name"/>

Bytes

2. Operation:

Public void onCreate (Bundle savedInstanceState ){

Super. onCreate (savedInstanceState );

SetContentView (R. layout. main );

String [] names = {"Lao Zhang", "Lao Fang", "Lao Bi", "Li Ming", "Li", "Chen Jiang", "abc", "acc "};

AutoCompleteTextViewnameText = (AutoCompleteTextView)

This. findViewById (R. id. name );

ArrayAdapter Adapter = new ArrayAdapter (

This, android. R. layout. simple_dropdown_item_1line, names );

NameText. setAdapter (adapter );

}

 

VII. ScrollView: scrolling content

 

 

Android: layout_width = "fill_parent"

Android: layout_height = "fill_parent"

Android: orientation = "vertical">

 

Android: layout_width = "match_parent"

Android: layout_height = "match_parent"

Android: id = "@ + id/TV"

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