用全屏DialogFragment代替Activity，结合ViewPager展示图片

最近在知乎上看到一篇很不错的分享，关于Fragment的一些用法和开发经验，其中提倡用全屏的DialogFragment代替Activity处理一些特殊的场景，比如用户点击item触发打开一些内容详情页，相册点击小图片时会将图片全屏放大展示…等等的这些场景都可以考虑用全屏的DialogFragment来代替Activity来代替进行视图的展示。

由于具体的代码逻辑非常简单，我就直接上代码了，注释也写得很清楚，你肯定能看懂：

public class FullScreenDlgFragment extends DialogFragment implements View.OnClickListener{      private int mClickItem;//对应显示ViewPager子项的位置      private List<String> mListImgUrls;      private ViewPager mViewPager;      private Integer[] mImgIds;//本地图片资源ID      private Dialog mDialog;      public static final String TAG_NAME=AlertDlgFragment.class.getName();      private Context mContext;        //即学即用的工厂方法      public static FullScreenDlgFragment newInstance(Context context, Integer[] imgIds, int clickItem) {          Bundle args = new Bundle();          FullScreenDlgFragment fragment = new FullScreenDlgFragment();          fragment.setArguments(args);          fragment.mContext = context;          fragment.mImgIds = imgIds;          fragment.mClickItem = clickItem;          return fragment;      }          //由ViewPager来响应点击      @Override      public void onClick(View v) {          this.dismiss();      }        @Override      public Dialog onCreateDialog(Bundle savedInstanceState) {          //设置Dialog样式          setStyle(DialogFragment.STYLE_NORMAL, R.style.CustomDialog_fill);          mDialog=new Dialog(mContext);          //去标题栏          mDialog.requestWindowFeature(Window.FEATURE_NO_TITLE);          initView();          return mDialog;      }        private void initView() {          //将Dialog设置全屏！！！          setDlgParams();            mViewPager = new ViewPager(mContext);          ViewGroup.LayoutParams params = new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT,                  ViewGroup.LayoutParams.MATCH_PARENT);          mViewPager.setLayoutParams(params);          mViewPager.setBackgroundColor(0xFF000000);          initViewPager();          mDialog.setContentView(mViewPager);      }        private void setDlgParams() {          ViewGroup.LayoutParams lay = mDialog.getWindow().getAttributes();          DisplayMetrics dm = new DisplayMetrics();          mDialog.getWindow().getWindowManager().getDefaultDisplay().getMetrics(dm);          Rect rect = new Rect();          View view = mDialog.getWindow().getDecorView();          view.getWindowVisibleDisplayFrame(rect);          lay.height = dm.heightPixels - rect.top;          lay.width = dm.widthPixels;      }        private void initViewPager() {          if (mImgIds != null && mImgIds.length > 0) {              List<View> listImgs = new ArrayList<>();              for (int i = 0; i < mImgIds.length; i++) {                  ImageView iv = new ImageView(mContext);                  ViewGroup.LayoutParams params = new ViewGroup.LayoutParams(                          ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT);                  iv.setLayoutParams(params);                  listImgs.add(iv);                  iv.setOnClickListener(this);                  iv.setImageResource(mImgIds[i]);                  // 加载网络图片                  // BitmapHelper.getInstance(mContext).display(iv,                  // mListImgUrls.get(i));              }              if (listImgs.size() > 0) {                  MyPagerAdapter pageAdapter = new MyPagerAdapter(listImgs);                  mViewPager.setAdapter(pageAdapter);                  mViewPager.setCurrentItem(mClickItem);              }          }      }  }

styles.xml

<style name="CustomDialog_fill" parent="Theme.AppCompat.Dialog">      <item name="android:windowNoTitle">true</item>      <item name="android:windowFrame">@null</item>      <item name="android:windowIsFloating">true</item>      <item name="android:windowIsTranslucent">true</item>      <item name="android:backgroundDimEnabled">false</item>      <item name="android:windowBackground">@android:color/white</item>  </style>

具体使用只需：

FullScreenDlgFragment.newInstance(this,new Integer[]{R.mipmap.p1,R.mipmap.p2,R.mipmap.p3,R.mipmap.p4},2).show(getFragmentManager(),AlertDlgFragment.TAG_NAME);

特别鸣谢，以下两篇文章：
【干货】Dialog的高冷用法
面条在知乎上“关于 Android，用多个 activity，还是单 activity 配合 fragment？”的回答