Android Development Engineer Anthology-Cue box, menu, data store, component chapter

Cue box, menu, data store, component toast

Toast.maketext (context, text, time). Show ();

Setduration ();//Set time
Setgravity ();//Location

Get:

Add Toast.getview ();
ImageView added to Toast, AddView ();

LayoutInflater inflater = LayoutInflater.from(this);View toast_view=inflater.inflate(R.id.,null);Toast.Toast.setView(toast_view);

Alertdialog

Alertdialog.builder

setTitle();setIcon();setView();setItems();setMultiChoiceItems(); 复选setSingleChoiceItems(); 单选setNeutralButton();setPositiveButton();setNegativeButton();

AlertDialog dialog = builder.create(); .show();消失dialog.dismiss();

Notification notification bar, such as receiving SMS

属性Notification setTicker();//手机状态栏的提示setWhen();//设置时间setContentTitle();setContentText();setContentIntent();Notification notification = builder.build();

Optionsmenu

onCreateOptionsMenu();动态：menu.add();监听：onOptionsItemSelected();

public boolean onCreateOptionsMenu(Menu menu){    getMenuInflater().inflate(R.menu.main,menu);    return true;}

Listening: onoptionsitemselected

public boolean onOptionsItemSelected(MenuItem item){    switch(item.getItemId()){        case R.id..:        ...    }}

ContextMenu context Menu

public boolean onCreateItemSelected(MenuItem item){}public void onCreateContextMenu(ContextMenu menu, View v, ContextMenuInfo menuInfo){    super.onCreateContextMenu(menu, v, menuIfo);}

Submenu Sub-Menu

protected void onCreate(Bundle savedInstanceState){    super.onCreate(savedInstanceState);    setContentView(R.layout.activity_main);}public boolean onCreateOptionsMenu(Menu menu){    getMenuInflater().inflate(R.menu.main, menu);    return true;    //return super.onOptionsItemSelected(item);}

Xml

<menu ...> <item  android:showAsAction="never"  android:title="文件">  <menu>   <item    android:id="@+id/.."    android:showAsAction="never"    android:title="打开"/></menu>

MenuInflater inflater = getMenuInflater();inflater.inflate(R.menu.main, menu);

How data is stored

Four kinds:

1. Sharedpreferences
2. Sqlite
3. Content Provider
4. File

Sharedpreferences is a relatively lightweight data store that stores some simple information based on XML key-value pairs.

Sharedpreferences can only get data can not be stored and modified, but can be implemented through the editor storage modifications.

Steps:

1. Get Sharedpreferences Object
2. Sharedpreferences.editor
3. The Putxxx method of editor
4. Editor.commit ()

SharedPreferences sharedPreferences = PreferenceManager.getDefaultSharedPreferences(MainActivity.this);

SharedPreferences sharedPreferences = getSharedPreferences("sharedPreferences", MODE_PRIVATE);Editor editor = sharedPreferences.edit();editor.putXXX();editor.commit();

Storage of user names and passwords

sharedPreferences = getSharedPreferences("UserInfo", MODE_PRIVATE);Editor editor = sharedPreferences.editor();

登录String name = etName.getText().toString().trim();String pass = etPass.getText().toString().trim();

SQLite forms, stored in a single file, stores 2T of memory in b-tree form.

The data type of SQLite, Null,integer,real,text,blob.

1. Sqlitedatabase
2. Sqliteopenhelper

SQLiteDatabase db = openOrCreateDatabase("table.db", MODE_PRIVATE, null);

Sqliteopenhelper

DBOpenHelper helper = new DBOpenHelper(MainActivity.this, "user.db");SQLiteDatabase db = helper.getWritableDatabase();Cursor c = db.rawQuery("select * from user", null);

public DBOpenHelper(Context context, String name, CursorFactory factory, int version){    super(context, name, factory, version);}public void onCreate(SQLiteDatabase db){}public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion){}

File file = this.getFilesDir();File file = this.getCacheDir();//重要文件就不要放在这里

Mode_private

Default action

Mode_append

Whether the file exists

public void WriteFiles(String content){    try{        FileOutputStream fileOutputStream = openFileOutput("super.txt", MODE_PRIVATE);        fileOutputStream.write(content.getBytes());        fileOutputStream.close();    }catch(){    }catch(){    }}

ContentProvider

<provider android:name="" android:authorities=""/>

public class MyContentProvider extends ContentProvider{    public int delete(Uri uri,String selection, String[] selectionArgs){    }}

Uri Common Resource Identifier

Broadcast broadcast

Broadcastreceiver Broadcast Receivers

Use: Requires Intent object, Sendbroadcast (), Sendorderbroadcast (), Sendstickybroadcast ().

Service

Registered:

<service android:name=""/>

public void onClick(View v){    switch(v.getId()){        case R.id.:        Intent intent = new Intent(MainActivity.this, MyService.class);        startService(intent);        break;    }}

public class MyService extends Service{    public void onCreate(){        super.onCreate();    }    public int onStartCommand(Intent intent,int flags,int startId){        return super.onStartCommand(intent,flags,startId);    }    public void onDestroy(){        super.onDestroy();    }    public IBinder onBind(Intent intent){        return null;    }}

Bind

public void onCreate(){}public IBinder onBind(Intent intent){}public void unbindService(ServiceConnection conn){}

ServiceConnection conn = new ServiceConnection(){    public void onServiceDisconnected(ComponentName name){    }    public void onServiceConnected(ComponentName name, IBinder binder){    }}

System Services

Mountservice,clipboardservice,getsystemservice ().

public Object getSystemService(String name){}

Power_service,powermanger Power Supply Service
Alarm_service,alarmmanager Alarm Clock Service

LayoutInflater inflater = MainActivity.this.getSystemService(LAYOUT_INFLATER_SERVICE);View view = inflater.inflate(R.layout. , null);setContentView(view);

Getsystemservice

Gesturedetector

MotionEvent,GestureDetector,onGestureListener.

Gestureoverlayview

Android:eventsInterceptionEnabledAndroid:fadeDurationAndroid:fadeEnabledAndroid:gestureColor

<android.gesture.GestureOverlayView  android:id="" android:layout_width="" android:layout_height=""> <ImageView  android:id=""  android:layout_width=""  android:layout_height=""</android.gesture.GestureOverlayView>  

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Android Development Engineer Anthology-Cue box, menu, data store, component chapter