直接写解决方法吧：

1、将XML里的静态引入删除：

<android.support.design.widget.NavigationView

        android:id="@+id/nav_view"

        android:layout_width="match_parent"

        android:layout_height="match_parent"

        android:layout_gravity="start" />

    <!--删除下面两行-->

    <!--app:headerLayout="@layout/nav_header"-->

    <!--app:menu="@menu/nav_menu"-->

2、在代码里 findViewById 找到 NavigationView，然后引入 Header 和 Menu，再获取头部布局，最后设置监听事件：

//findviewbyid

navigationView = (NavigationView) findViewById(R.id.nav_view);

//引入header和menu

navigationView.inflateHeaderView(R.layout.nav_header);

navigationView.inflateMenu(R.menu.nav_menu);

//获取头部布局

View navHeaderView = navigationView.getHeaderView(0);

3、完整代码如下：

private void initNavigation() {

        drawerLayout = (DrawerLayout) findViewById(R.id.drawer_layout);

        navigationView = (NavigationView) findViewById(R.id.nav_view);

        //引入header和menu

        navigationView.inflateHeaderView(R.layout.nav_header);

        navigationView.inflateMenu(R.menu.nav_menu);

        //设置menu的监听事件

        navigationView.setNavigationItemSelectedListener(new NavigationView.OnNavigationItemSelectedListener() {

            @Override

            public boolean onNavigationItemSelected(@NonNull MenuItem item) {

                switch (item.getItemId()) {

                    case R.id.add_city:

                        //启动

                        startActivityForResult(new Intent(MainActivity.this, CityPickerActivity.class),

                                REQUEST_CODE_PICK_CITY);

                        drawerLayout.closeDrawers();

                        break;

                    case R.id.setting:

                        Intent SettingIntent = new Intent(MainActivity.this, SettingActivity.class);

                        startActivity(SettingIntent);

                        drawerLayout.closeDrawers();

                        break;

                    case R.id.about:

                        Intent aboutIntent = new Intent(MainActivity.this, aboutActivity.class);

                        startActivity(aboutIntent);

                        drawerLayout.closeDrawers();

                        break;

                }

                return false;

            }

        });

        //获取头部布局

        View navHeaderView = navigationView.getHeaderView(0);

        //设置监听事件

        icon_image = (CircleImageView) navHeaderView.findViewById(R.id.icon_image);

        icon_image.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View view) {

                dialog.show();

            }

        });

        //读取头像

        Utility.getImageFromShare(this, icon_image);

        //dialog

        dialog = new CustomDialog(this, 100, 100, R.layout.dialog_photo, R.style.Theme_dialog,

                Gravity.BOTTOM, R.style.pop_anim_style);

        //屏幕外点击无效

        dialog.setCancelable(false);

        btn_camera = (Button) dialog.findViewById(R.id.btn_camera);

        btn_camera.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View view) {

                toCamera();

            }

        });

        btn_picture = (Button) dialog.findViewById(R.id.btn_picture);

        btn_picture.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View view) {

                toPicture();

            }

        });

        btn_cancel = (Button) dialog.findViewById(R.id.btn_cancel);

        btn_cancel.setOnClickListener(new View.OnClickListener() {

            @Override

            public void onClick(View view) {

                dialog.dismiss();

            }

        });

    }