Android开发工程师文集-提示框，菜单，数据存储，组件篇

提示框，菜单，数据存储，组件篇

Toast

Toast.makeText(context, text, 时间).show();

setDuration();//设置时间
setGravity();//位置

获取：

添加toast.getView();
imageView添加到toast中，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通知栏，如接收短信

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;
}

监听：onOptionsItemSelected

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

ContextMenu上下文菜单

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

SubMenu 子菜单

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

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

数据存储方式

四种：

SharedPreferences
SQLite
Content Provider
File

SharedPreferences是一种比较轻型的数据存储，基于xml的键值对存储，存储一些简单的信息。

SharedPreferences只能获取数据不能存储和修改，但能通过Editor实现存储修改。

步骤：

获取SharedPreferences对象
SharedPreferences.Editor
Editor的putXXX的方法
Editor.commit()

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

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

用户名和密码的存储

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

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

SQLite的形式，以单个文件的存储，存储2T内存，以B-Tree形式。

SQLite的数据类型，null,integer,real,text,blob。

SQLiteDatabase
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

默认操作

MODE_APPEND

文件是否存在

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

ContentProvider

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

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

Uri 通用资源标志符

Broadcast广播

BroadcastReceiver 广播接收器

使用：需要Intent对象，sendBroadcast(),sendOrderBroadcast(),sendStickyBroadcast()。

Service

<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){}
}

系统服务

MountService,ClipboardService,getSystemService().

public Object getSystemService(String name){}

POWER_SERVICE,PowerManger电源服务
ALARM_SERVICE,AlarmManager闹钟服务

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

getSystemService

GestureDetector

MotionEvent,GestureDetector,onGestureListener.

GestureOverlayView

Android:eventsInterceptionEnabled
Android:fadeDuration
Android:fadeEnabled
Android:gestureColor

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

定位：分享 Android&Java 知识点
完结！