Learn android from scratch (Dialog box. 25 .)

Learn android from scratch (Dialog box. 25 .)
In the graphic interface, the dialog box is also an important form of human-computer interaction. The program can prompt users with some information through the dialog box, you can also perform some simple interaction operations with the program through the dialog box. During Android development, all the dialogs are inherited from the android. app. Dialog class. The Inheritance structure is as follows: java. lang. Object? Android. app. Dialog
Common DIalog Methods

1	Public void setTitle (CharSequence title)	Normal	Set the display title of the dialog box
2	Public void setTitle (int titleId)	Normal	Set the title of the dialog box. The content is specified for the resource file.
3	Public void show ()	Normal	Show dialog box
4	Public void hide ()	Normal	Hide dialog box
5	Public boolean isShowing ()	Normal	Check whether the dialog box is displayed
6	Public void setContentView (View view)	Normal	Set View Components
7	Public void setContentView (int layoutResID)	Normal	Set the View component ID
8	Public void dismiss ()	Normal	Hide dialog box
9	Public void closeOptionsMenu ()	Normal	Close option menu
10	Public void setDismissMessage (Message msg)	Normal	Set the message in the hide dialog box
11	Public void setCancelable (boolean flag)	Normal	Whether the setting can be canceled
12	Public void setCancelMessage (Message msg)	Normal	Set the message when the dialog box is canceled
13	Public void cancel ()	Normal	The cancel dialog box is similar to the dismiss () method.
14	Public Window getWindow ()	Normal	Retrieve Window object
15	Public void setOnShowListener (DialogInterface. OnShowListener listener)	Normal	Listener when the Setting dialog box is opened
16	Public void setOnDismissListener (DialogInterface. OnDismissListener listener)	Normal	Listener when the dialog box is hidden
17	Public void setOnCancelListener (DialogInterface. OnCancelListener listener)	Normal	Set dialog box to cancel listening

In general, we use the internal class in AlertDialog to instantiate the dialog object.
You can understand the commonly used methods in DIalog. The details are described in the Code.

1	Public AlertDialog. Builder (Context context)	Structure	Create AlertDialog. Builder object
2	Public AlertDialog. Builder setMessage (int messageId)	Normal	Set the resource ID of the displayed information
3	Public AlertDialog. Builder setMessage (CharSequence message)	Normal	Set the string of the display information
4	Public AlertDialog. Builder setView (View view)	Normal	Set the displayed View component
5	Public AlertDialog. Builder setSingleChoiceItems (CharSequence [] items, int checkedItem, DialogInterface. OnClickListener listener)	Normal	The Setting dialog box displays a single-choice List, specifying the selected items by default, and setting the listener processing operation.
6	Public AlertDialog. Builder setSingleChoiceItems (ListAdapter adapter, int checkedItem, DialogInterface. OnClickListener listener)	Normal	The Setting dialog box displays a single-choice List, specifying the selected items by default, and setting the listener processing operation.
7	Public AlertDialog. Builder setMultiChoiceItems (CharSequence [] items, boolean [] checkedItems, DialogInterface. OnMultiChoiceClickListener listener)	Normal	The Setting dialog box displays a checklist and sets the listener processing operation.
8	Public AlertDialog. Builder setPositiveButton (CharSequence text, DialogInterface. OnClickListener listener)	Normal	Add a confirmation button for the dialog box and set the listening operation
9	Public AlertDialog. Builder setPositiveButton (int textId, DialogInterface. OnClickListener listener)	Normal	Add a confirmation button for the dialog box. The displayed content is specified by the resource file and the listener operation is set.

10	Public AlertDialog. Builder setNegativeButton (CharSequence text, DialogInterface. OnClickListener listener)	Normal	Set a Cancel button for the dialog box and set the listener operation
11	Public AlertDialog. Builder setNegativeButton (int textId, DialogInterface. OnClickListener listener)	Normal	Set a Cancel button for the dialog box. The displayed content is specified by the resource file and the listener operation is set.
12	Public AlertDialog. Builder setNeutralButton (CharSequence text, DialogInterface. OnClickListener listener)	Normal	Set a common button and a listener
13	Public AlertDialog. Builder setNeutralButton (int textId, DialogInterface. OnClickListener listener)	Normal	Set a common button to display the content specified by the resource file and set the listening operation
14	Public AlertDialog. Builder setItems (CharSequence [] items, DialogInterface. OnClickListener listener)	Normal	Set the information content as a list item and set the listening operation
15	Public AlertDialog. Builder setItems (int itemsId, DialogInterface. OnClickListener listener)	Normal	Sets the information content as a list item. The content of the list item is specified by the resource file, and sets the listening operation.
16	Public AlertDialog create ()	Normal	Create an instantiation object of AlertDialog
17	Public AlertDialog. Builder setIcon (Drawable icon)	Normal	Set the displayed icon
18	Public AlertDialog. Builder setIcon (int iconId)	Normal	Set the resource ID of the icon to be displayed

I understand the AlertDialog method. Let's take a look at the example.

1 * the simplest dialog box * button1
2 ****** dialog box with buttons ******** button2
3 ****** dialog box with event ******** button3
4 ****** dialog box with options ******** button4
5 * single-choice dialog box * button5
6 * button6
* With progress bar dialog box * button7
8 * Date selection dialog box * button8
9 * Event Selection dialog box * button9
10 * User-defined dialog box * button10


See the code below
Main XML file

Custom M. xml

 
     
          
           
       
      
          
           
   ?
  
 

JAVA files

Package com. example. dialog; import android. app. activity; import android. app. alertDialog; import android. app. datePickerDialog; import android. app. datePickerDialog. onDateSetListener; import android. app. dialog; import android. app. progressDialog; import android. app. timePickerDialog; import android. app. timePickerDialog. onTimeSetListener; import android. content. dialogInterface; import android. OS. bundle; import android Oid. view. layoutInflater; import android. view. view; import android. view. view. onClickListener; import android. widget. button; import android. widget. datePicker; import android. widget. timePicker; import android. widget. toast; public class MainActivity extends Activity {private Button button1, button2, button3, button4, button5, button6, button7, button8, button9, button10; private String CityData [] = {"Henan", "Beijing", "Shanghai", "Tianjin", "Hunan", "Shenzhen"}; // city Data private String SexData [] = {"male", "female "}; // gender data private String ColorData [] = {"red", "orange", "yellow", "green", "blue", "Purple "}; // color data private boolean ColorChoiced [] = {false, false}; // sets the default option @ Overrideprotected void onCreate (Bundle savedInstanceState) {super. onCreate (savedInstanceState); setContentView (R. layout. activity_main); // instantiate button1 = for the button (Button) this. findViewById (R. id. button1); button2 = (Button) this. findViewById (R. id. button2); button3 = (Button) this. findViewById (R. id. button3); button4 = (Button) this. findViewById (R. id. button4); button5 = (Button) this. findViewById (R. id. button5); button6 = (Button) this. findViewById (R. id. button6); button7 = (Button) this. findViewById (R. id. button7); button8 = (Button) this. findViewById (R. id. button8); B Utton9 = (Button) this. findViewById (R. id. button9); button10 = (Button) this. findViewById (R. id. button10); // The simplest dialog box, button1.setOnClickListener (new OnClickListener () {@ Overridepublic void onClick (View view) {// TODO Auto-generated method stubDialog dialog = new AlertDialog. builder (MainActivity. this ). setTitle ("About Us") // set the title. setMessage ("Feiyang software Co., Ltd.") // sets the prompt information. setIcon (R. drawable. a2) // set the icon. create (); // create dialog box dial Og. show (); // display dialog box}); // Information Processing dialog box with buttons button2.setOnClickListener (new View. onClickListener () {@ Overridepublic void onClick (View view) {// TODO Auto-generated method stubDialog dialog = new AlertDialog. builder (MainActivity. this ). setTitle ("delete information") // set the title. setMessage ("are you sure you want to delete this message? ") // Set the prompt information. setIcon (R. drawable. a2) // set the icon. setNegativeButton ("cancel", null) // sets the cancel button. setPositiveButton ("OK", null) // sets the OK button. create (); // create dialog box dialog. show (); // display dialog box}); // The button3.setOnClickListener (new OnClickListener () {@ Overridepublic void onClick (View view) dialog box with Event Processing) {// TODO Auto-generated method stubDialog dialog = new AlertDialog. builder (MainActivity. this ). setTitle ("Exit program "). setMessage ("are you sure you want to exit the program? "). SetIcon (R. drawable. a2 ). setPositiveButton ("OK", new DialogInterface. onClickListener () {@ Overridepublic void onClick (DialogInterface dialogInterface, int whitch) {// TODO Auto-generated method stubToast. makeText (MainActivity. this, "the program is about to exit", 2 ). show (); // finish (); In order to demonstrate the effect, do not actually exit, use the toast instead }}). setNegativeButton ("cancel", new DialogInterface. onClickListener () {@ Overridepublic void onClick (DialogInterface arg0, int Arg1) {// TODO Auto-generated method stub }}). create (); dialog. show () ;}}); // dialog box list button4.setOnClickListener (new View. onClickListener () {@ Overridepublic void onClick (View view) {// TODO Auto-generated method stubDialog dialog = new AlertDialog. builder (MainActivity. this ). setTitle ("select your employment City "). setIcon (R. drawable. a2 ). setNegativeButton ("cancel", null ). setItems (CityData, new DialogInterface. onClickListener () {@ Overridepublic void onClick (DialogInterface dInterface, int whitch) {// TODO Auto-generated method stubToast. makeText (MainActivity. this, "you selected:" + CityData [whitch], 2 ). show ();}}). create (); dialog. show () ;}}); // The button5.setOnClickListener (new View. onClickListener () {@ Overridepublic void onClick (View view) {// TODO Auto-generated method stubDialog dialog = new AlertDialog. builder (MainActivit Y. this ). setTitle ("select your gender "). setSingleChoiceItems (SexData, 0, new DialogInterface. onClickListener () {@ Overridepublic void onClick (DialogInterface dInterface, int whitch) {// TODO Auto-generated method stubToast. makeText (MainActivity. this, "you selected:" + SexData [whitch], 2 ). show ();}}). setIcon (R. drawable. a2 ). setNegativeButton ("cancel", null ). setPositiveButton ("OK", null ). create (); dialog. show () ;}}); // dialog box with multiple selection boxes, Ton6.setOnClickListener (new View. onClickListener () {@ Overridepublic void onClick (View view) {// TODO Auto-generated method stubDialog dialog = new AlertDialog. builder (MainActivity. this ). setTitle ("select your preferred color "). setMultiChoiceItems (ColorData, ColorChoiced, new DialogInterface. onMultiChoiceClickListener () {@ Overridepublic void onClick (DialogInterface dialog, int whitch, boolean isChecked) {// TODO Auto-ge Nerated method stubToast. makeText (MainActivity. this, "you selected" + ColorData [whitch], 2 ). show (); // No judgment is made here, so this event is triggered whether selected or deselected. Interested readers can set IsChecked judgment }}). setIcon (R. drawable. a2 ). setNegativeButton ("cancel", null ). setPositiveButton ("OK", null ). create (); dialog. show () ;}}); button7.setOnClickListener (new View. onClickListener () {@ Overridepublic void onClick (View view) {// TODO Auto-generated method stubfinal Progress Dialog dialog = new ProgressDialog (MainActivity. this); dialog. setMessage ("loading information. Please wait! "); Dialog. setTitle ("loading"); dialog. setIcon (R. drawable. a2); dialog. onStart (); new Thread () {@ Overridepublic void run () {// TODO Auto-generated method stubtry {Thread. sleep (3*1000);} catch (InterruptedException e) {// TODO Auto-generated catch blocke. printStackTrace ();} finally {dialog. dismiss ();}}}. start (); dialog. show () ;}}); // Date selection dialog box button8.setOnClickListener (new View. onClickListener () {@ Overridepublic void onClick (View view) {// TODO Auto-generated method stubDatePickerDialog dialog = new DatePickerDialog (MainActivity. this, new OnDateSetListener () {@ Overridepublic void onDateSet (DatePicker datePicker, int year, int monthOfYear, int dayOfMonth) {// TODO Auto-generated method stubToast. makeText (MainActivity. this, "the set time is:" + year + "year" + (monthOfYear + 1) // Add 1 to month, the original month starts from scratch + "month" + dayOfMonth + "day", 2 ). show () ;},2014, 8, 17); dialog. show () ;}}); // Time Selection dialog box button9.setOnClickListener (new View. onClickListener () {@ Overridepublic void onClick (View view) {// TODO Auto-generated method stubTimePickerDialog dialog = new TimePickerDialog (MainActivity. this, new OnTimeSetListener () {@ Overridepublic void onTimeSet (TimePicker arg0, int hourOfDay, int minute) {// TODO Auto-generated method stubToast. makeText (MainActivity. this, "set the time to:" + hourOfDay + "Hour" + minute + "minute", 2 ). show () ;}, 20, 55, true); dialog. show () ;}}); // custom dialog box button10.setOnClickListener (new View. onClickListener () {@ Overridepublic void onClick (View view) {// TODO Auto-generated method stubView myView = LayoutInflater. from (getApplication ()). inflate (R. layout. custom, null); // converts the layout object to the VIew object Dialog dialog = new AlertDialog. builder (MainActivity. this ). setTitle ("User Login "). setIcon (R. drawable. a2 ). setNegativeButton ("cancel", null ). setPositiveButton ("login", null ). setView (myView) // set the View component to be displayed. create (); dialog. show ();}});}}

Returns the corresponding button effect in sequence.














Through the single-choice and multi-choice dialog boxes, you can design a lot of user interaction, progress bars, threads, and asynchronous operations to process time-consuming operations. The custom dialog box greatly increases the diversity of the UI, it is possible to better feedback interaction.

Next prediction: ImageSwitcher image switching component