Android NavigationView头部设置监听事件

<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"-- 

//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);

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();
      }
    });

  }