Question

我已经为我的片段实现了一个导航抽屉，因此想知道什么是仅为片段实现后按功能的最佳方式以及代码必须要去的地方？我在下面使用了一些后退代码，但它不起作用。

活动类

public class BakerlooHDNActivity extends AppCompatActivity {

    //save our header or result
    private Drawer result = null;

    private int getFactorColor(int color, float factor) {
        float[] hsv = new float[3];
        Color.colorToHSV(color, hsv);
        hsv[2] *= factor;
        color = Color.HSVToColor(hsv);
        return color;
    }

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_bakerloo_hdn);



        LocalBroadcastManager.getInstance(this).registerReceiver(onNotice, new IntentFilter("BACKPRESSED_TAG"));


        final String actionBarColor = "#B36305";

        Toolbar mToolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(mToolbar);

        if(getSupportActionBar()!=null) {
            getSupportActionBar().setDisplayHomeAsUpEnabled(true);
            getSupportActionBar().setDisplayShowHomeEnabled(false);
            getSupportActionBar().setTitle(Html.fromHtml("<font color='#FFFFFF'>" + getResources().getString(R.string.hdn) + "</font>"));

            final Drawable upArrow = ContextCompat.getDrawable(this, R.drawable.abc_ic_ab_back_mtrl_am_alpha);
            upArrow.setColorFilter(getResources().getColor(R.color.white), PorterDuff.Mode.SRC_ATOP);
            getSupportActionBar().setHomeAsUpIndicator(upArrow);
        }

        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.LOLLIPOP) {
            Window window = getWindow();
            window.addFlags(WindowManager.LayoutParams.FLAG_DRAWS_SYSTEM_BAR_BACKGROUNDS);
            getWindow().setStatusBarColor(getFactorColor(Color.parseColor(actionBarColor), 0.8f));
        }

        // start of navigation drawer
        AccountHeader headerResult = new AccountHeaderBuilder()
            .withActivity(this)
            .withCompactStyle(true)
            .withHeaderBackground(R.color.bakerloo)
            .withProfileImagesVisible(false)
            .withTextColor(Color.parseColor("#FFFFFF"))
            .withSelectionListEnabled(false)

            .addProfiles(
                    new ProfileDrawerItem().withName(getString(R.string.hello)).withEmail(getString(R.string.world))
            )
            .build();

        result = new DrawerBuilder()
            .withActivity(this)
            .withAccountHeader(headerResult)
            .withTranslucentStatusBar(false)
            .withActionBarDrawerToggle(false)
            .withSelectedItem(-1)
            .addDrawerItems(
                    new SectionDrawerItem().withName(R.string.other_lines_nocaps).setDivider(false),
                    new PrimaryDrawerItem().withName(R.string.hello_world).withIdentifier(1).withCheckable(false)
            )
            .build();
        // end of navigation drawer
    }


    @Override
    public void onBackPressed() {
        if (result.isDrawerOpen()) {
            result.closeDrawer();
        } else {
            super.onBackPressed();
        }

        LocalBroadcastManager.getInstance(context).sendBroadcast(new Intent("BACKPRESSED_TAG"));
    }
}

片段类

public class FragmentBakerlooHDN extends android.support.v4.app.Fragment {

    public FragmentBakerlooHDN() {
        // Required empty constructor
    }

    BroadcastReceiver onNotice = new BroadcastReceiver() {
        @Override
        public void onReceive(Context context, Intent intent) {
            // do stuff when back in activity is pressed
             headerResult.closeDrawer();
        }
    };

    // Declaring navigation drawer
    private AccountHeader headerResult = null;
    private Drawer result = null;


    /**
     * Whether or not the activity is in two-pane mode, i.e. running on a tablet
     * device.
     */
    private boolean mTwoPane;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        LocalBroadcastManager.getInstance(getActivity()).registerReceiver(onNotice, new IntentFilter("BACKPRESSED_TAG"));

        super.onCreate(savedInstanceState);
    }

    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        View v = inflater.inflate(R.layout.fragment_bakerloo_hdn, container, false);


        headerResult = new AccountHeaderBuilder()
                .withActivity(getActivity())
                .withCompactStyle(true)
                .withHeaderBackground(R.color.bakerloo)
                .withProfileImagesVisible(false)
                .withTextColor(Color.parseColor("#FFFFFF"))
                .withSelectionListEnabled(false)

                .addProfiles(
                        new ProfileDrawerItem().withName(getString(R.string.hdn)).withEmail(getString(R.string.hello_world))
                )
                .build();

        result = new DrawerBuilder()
                .withActivity(getActivity())
                .withAccountHeader(headerResult)
                .withTranslucentStatusBar(false)
                .withActionBarDrawerToggle(false)
                .withSelectedItem(-1)
                .addDrawerItems(
                new PrimaryDrawerItem().withName(R.string.hello_world).withIdentifier(1).withCheckable(false)
                )
                .build();


        super.onCreate(savedInstanceState);
        return v;
    }

    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        View v = getView();

        super.onActivityCreated(savedInstanceState);
    }
}

Answer 1

onBackPressed()中没有Fragment。这是Activity的方法。你可以做什么，你可以让你的活动在调用onBackPressed()时调用你的片段方法：

@Override
public void onBackPressed() {
    if (!frag.onBackPressed() ) {
        super.onBackPressed();
    }
}

然后你的片段的onBackPressed() could do anything you want and return为真when it done anything, or为false，所以你可以在这种情况下调用super的。

如何启用反压以仅关闭片段上的导航抽屉

1 个答案: