《阿里Android手册》笔记

Activity 的 layout 以 module_activity 开头
Fragment 的 layout 以 module_fragment 开头
Dialog 的 layout 以 module_dialog 开头
include 的 layout 以 module_include 开头
ListView 的行 layout 以 module_list_item 开头
RecyclerView 的 item layout 以 module_recycle_item 开头
GridView 的行 layout 以 module_grid_item 开头

module_login_btn_pressed
module_tabs_icon_home_normal

module_login_btn_p
module_tabs_icon_home_n

模块名_逻辑名称_[方向|序号]

LinearLayout        ll
RelativeLayout      rl
ConstraintLayout    cl
ListView            lv
ScollView           sv
TextView            tv
Button              btn
ImageView           iv
CheckBox            cb
RadioButton         rb
EditText            et

ProgressBar 对应的缩写为 progress_bar
DatePicker 对应的缩写为 date_picker

public void viewUrl(String url, String mimeType) {
    Intent intent = new Intent(Intent.ACTION_VIEW);
    intent.setDataAndType(Uri.parse(url), mimeType);
    if (getPackageManager().resolveActivity(intent, PackageManager.MATCH_DEFAULT_ONLY) != null) {
        try {
            startActivity(intent);
        } catch (ActivityNotFoundException e) {
            e.printStackTrace();
        }
    }
}

public void showPromptDialog(String text){
    DialogFragment promptDialog = new DialogFragment() {
        @Override
        public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
            getDialog().requestWindowFeature(Window.FEATURE_NO_TITLE);
            View view = inflater.inflate(R.layout.fragment_prompt, container);
            return view;
        }
    };
    promptDialog.show(getFragmentManager(), text);
}

<?xml version="1.0" encoding="utf-8"?>
<animation-list xmlns:android="http://schemas.android.com/apk/res/android" android:oneshot
="true">
<item android:duration="500" android:drawable="@drawable/ic_heart_100"/>
<item android:duration="500" android:drawable="@drawable/ic_heart_75"/>
<item android:duration="500" android:drawable="@drawable/ic_heart_50"/>
<item android:duration="500" android:drawable="@drawable/ic_heart_25"/>
<item android:duration="500" android:drawable="@drawable/ic_heart_0"/>
</animation-list>

int NUMBER_OF_CORES = Runtime.getRuntime().availableProcessors();
int KEEP_ALIVE_TIME = 1;
TimeUnit KEEP_ALIVE_TIME_UNIT = TimeUnit.SECONDS;
BlockingQueue<Runnable> taskQueue = new LinkedBlockingQueue<Runnable>();
ExecutorService executorService = new ThreadPoolExecutor(NUMBER_OF_CORES,
        NUMBER_OF_CORES*2, KEEP_ALIVE_TIME, KEEP_ALIVE_TIME_UNIT, taskQueue,
        new BackgroundThreadFactory(), new DefaultRejectedExecutionHandler());
//执行任务
executorService.execute(new Runnnable() {
    ...

int NUMBER_OF_CORES = Runtime.getRuntime().availableProcessors();
int KEEP_ALIVE_TIME = 1;
TimeUnit KEEP_ALIVE_TIME_UNIT = TimeUnit.SECONDS;
BlockingQueue<Runnable> taskQueue = new LinkedBlockingQueue<Runnable>();
ExecutorService executorService = new ThreadPoolExecutor(NUMBER_OF_CORES,
NUMBER_OF_CORES*2, KEEP_ALIVE_TIME, KEEP_ALIVE_TIME_UNIT,
taskQueue, new BackgroundThreadFactory(), new DefaultRejectedExecutionHandler());

public class MyThread extends Thread {
public MyThread(){
	super.setName("ThreadName"); …
	}
}

public void insertUserPhoto(SQLiteDatabase db, String userId, String content) {
    ContentValues cv = new ContentValues();
    cv.put("userId", userId);
    cv.put("content", content);
    db.beginTransaction();
    try {
        db.insert(TUserPhoto, null, cv);
        // 其他操作
        db.setTransactionSuccessful();
    } catch (Exception e) {
    // TODO
    } finally {
        db.endTransaction();
    }
}

public void insertBulk(SQLiteDatabase db, ArrayList<UserInfo> users) {
    db.beginTransaction();
    try {
        for (int i = 0; i < users.size; i++) {
            ContentValues cv = new ContentValues();
            cv.put("userId", users[i].userId);
            cv.put("content", users[i].content);
            db.insert(TUserPhoto, null, cv);
        }
		// 其他操作
        db.setTransactionSuccessful();
    } catch (Exception e) {
        // TODO
    } finally {
        db.endTransaction();
    }
}

class BitmapWorkerTask extends AsyncTask<Integer, Void, Bitmap> {
...
    // 在后台进行图片解码
    @Override
    protected Bitmap doInBackground(Integer... params) {
        final Bitmap bitmap = BitmapFactory.decodeFile("some path");
        return bitmap;
    }
...
}

public static Bitmap decodeSampledBitmapFromResource(Resources res, int resId,
                                                     int reqWidth, int reqHeight) {
    // 首先通过 inJustDecodeBounds=true 获得图片的尺寸
    final BitmapFactory.Options options = new BitmapFactory.Options();
    options.inJustDecodeBounds = true;
    BitmapFactory.decodeResource(res, resId, options);
    // 然后根据图片分辨率以及我们实际需要展示的大小，计算压缩率
    options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
    // 设置压缩率，并解码
    options.inJustDecodeBounds = false;
    return BitmapFactory.decodeResource(res, resId, options);
}

    public static Bitmap decodeSampledBitmapFromFile(String filename,
                                                     int reqWidth, int reqHeight, ImageCache cache) {
        final BitmapFactory.Options options = new BitmapFactory.Options();
        ...
        BitmapFactory.decodeFile(filename, options);
        ...
        // 如果在 Honeycomb 或更新版本系统中运行，尝试使用 inBitmap
        if (Utils.hasHoneycomb()) {
            addInBitmapOptions(options, cache);
        }
        ...
        return BitmapFactory.decodeFile(filename, options);
    }
 
    private static void addInBitmapOptions(BitmapFactory.Options options,
                                           ImageCache cache) {
		// inBitmap 只处理可变的位图， 所以强制返回可变的位图
        options.inMutable = true;
        if (cache != null) {
            Bitmap inBitmap = cache.getBitmapFromReusableSet(options);
            if (inBitmap != null) {
                options.inBitmap = inBitmap;
            }
        }
    }

Config config = drawableSave.getOpacity() != PixelFormat.OPAQUE ? Config.ARGB_8888 :
Config.RGB_565;
Bitmap bitmap = Bitmap.createBitmap(w, h, config);