Android 项目及编码的规范

void setServerPort(String value) {
    try {
        serverPort = Integer.parseInt(value);
    } catch (NumberFormatException e) { }
}

try {
    someComplicatedIOFunction();        // may throw IOException
    someComplicatedParsingFunction();   // may throw ParsingException
    someComplicatedSecurityFunction();  // may throw SecurityException
    // phew, made it all the way
} catch (Exception e) {                 // I'll just catch all exceptions
    handleError();                      // with one generic handler!
}

if (x == 1) {
    x++;
}

Instrument i =
        someLongExpression(that, wouldNotFit, on, one, line);

class MyClass {
    int func() {
        if (something) {
            // ...
        } else if (somethingElse) {
            // ...
        } else {
            // ...
        }
    }
}

if (condition) body();

if (condition)
    body();  // bad!

public class Child extends Parent {

    private static final int CONSTANT = 1;

    private String mName;
    private int mAge;

    public Child(String name, int age) {
        mName = name;
        mAge = age;
    }

    @Override
    public void changeName() {
        ...
    }

    public void setName(String name) {
            mName = name;
    }

    private void setSomething() {
        ...
    }

    static class AnInnerClass {

    }
}

public class MainActivity extends Activity {

    //Order matches Activity lifecycle
    @Override
    public void onCreate() {}

    @Override
    public void onResume() {}

    @Override
    public void onPause() {}

    @Override
    public void onDestroy() {}

}

// Context always goes first
public User loadUser(Context context, int userId);

// Callbacks always go last
public void loadUserAsync(Context context, int userId, UserCallback callback);

// Note the value of the field is the same as the name to avoid duplication issues
static final String PREF_EMAIL = "PREF_EMAIL";
static final String BUNDLE_AGE = "BUNDLE_AGE";
static final String ARGUMENT_USER_ID = "ARGUMENT_USER_ID";

// Intent-related items use full package name as value
static final String EXTRA_SURNAME = "com.myapp.extras.EXTRA_SURNAME";
static final String ACTION_OPEN_USER = "com.myapp.action.ACTION_OPEN_USER";

public static Intent getStartIntent(Context context, User user) {
    Intent intent = new Intent(context, ThisActivity.class);
    intent.putParcelableExtra(EXTRA_USER, user);
    return intent;
}

public static UserFragment newInstance(User user) {
    UserFragment fragment = new UserFragment;
    Bundle args = new Bundle();
    args.putParcelable(ARGUMENT_USER, user);
    fragment.setArguments(args)
    return fragment;
}

int longName = anotherVeryLongVariable + anEvenLongerOne - thisRidiculousLongOne
        + theFinalOne;

int longName =
        anotherVeryLongVariable + anEvenLongerOne - thisRidiculousLongOne + theFinalOne;

Picasso.with(context).load("http://ribot.co.uk/images/sexyjoe.jpg").into(imageView);

Picasso.with(context)
        .load("http://ribot.co.uk/images/sexyjoe.jpg")
        .into(imageView);

loadPicture(context, "http://ribot.co.uk/images/sexyjoe.jpg", mImageViewProfilePicture, clickListener, "Title of the picture");

loadPicture(
        context,
        "http://ribot.co.uk/images/sexyjoe.jpg",
        mImageViewProfilePicture,
        clickListener,
        "Title of the picture"
   );

public Observable<Location> syncLocations() {
    return mDatabaseHelper.getAllLocations()
            .concatMap(new Func1<Location, Observable<? extends Location>>() {
                @Override
                 public Observable<? extends Location> call(Location location) {
                     return mRetrofitService.getLocation(location.id);
                 }
            })
            .retry(new Func2<Integer, Throwable, Boolean>() {
                 @Override
                 public Boolean call(Integer numRetries, Throwable throwable) {
                     return throwable instanceof RetrofitError;
                 }
            });
}

<TextView
    android:id="@+id/text_view_profile"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />

<!-- Don\'t do this! -->
<TextView
    android:id="@+id/text_view_profile"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" >
</TextView>

<ImageView
    android:id="@+id/image_profile"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content" />

<menu>
    <item
        android:id="@+id/menu_done"
        android:title="Done" />
</menu>

static class Foo {
    int mSplat;
}

Foo[] mArray = ...

// 最慢,消耗最多
public void zero() {
    int sum = 0;
    for (int i = 0; i < mArray.length; ++i) {
        sum += mArray[i].mSplat;
    }
}

public void one() {
    int sum = 0;
    Foo[] localArray = mArray;
    int len = localArray.length;

    for (int i = 0; i < len; ++i) {
        sum += localArray[i].mSplat;
    }
}

// 推荐
public void two() {
    int sum = 0;
    for (Foo a : mArray) {
        sum += a.mSplat;
    }
}