第一个页面终于可以显示所有图片并且能滑动了

app/src/main/java/com/taifua/material/FileManager.java

@@ -0,0 +1,103 @@
+package com.taifua.material;
+
+import android.content.ContentResolver;
+import android.content.Context;
+import android.database.Cursor;
+import android.provider.MediaStore;
+
+import java.io.File;
+import java.io.FilenameFilter;
+import java.util.ArrayList;
+import java.util.List;
+
+public class FileManager {
+    private static FileManager mInstance;
+    private static Context mContext;
+    private static ContentResolver mContentResolver;
+    private static Object mLock = new Object();
+
+    public static FileManager getInstance(Context context) {
+        if (mInstance == null) {
+            synchronized (mLock) {
+                if (mInstance == null) {
+                    mInstance = new FileManager();
+                    mContext = context;
+                    mContentResolver = context.getContentResolver();
+                }
+            }
+        }
+        return mInstance;
+    }
+
+
+    /**
+     * 通过图片文件夹的路径获取该目录下的图片
+     */
+    public List<String> getImgListByDir(String dir) {
+        ArrayList<String> imgPaths = new ArrayList<>();
+        File directory = new File(dir);
+        if (directory == null || !directory.exists()) {
+            return imgPaths;
+        }
+        File[] files = directory.listFiles();
+        for (File file : files) {
+            String path = file.getAbsolutePath();
+            if (FileUtils.isPicFile(path)) {
+                imgPaths.add(path);
+            }
+        }
+        return imgPaths;
+    }
+
+    /**
+     * 得到图片文件夹集合
+     */
+    public List<ImgFolderBean> getImageFolders() {
+        List<ImgFolderBean> folders = new ArrayList<ImgFolderBean>();
+        // 扫描图片
+        Cursor c = null;
+        try {
+            c = mContentResolver.query(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, null,
+                    MediaStore.Images.Media.MIME_TYPE + "= ? or " + MediaStore.Images.Media.MIME_TYPE + "= ?",
+                    new String[]{"image/jpeg", "image/png"}, MediaStore.Images.Media.DATE_MODIFIED);
+            List<String> mDirs = new ArrayList<String>();//用于保存已经添加过的文件夹目录
+            while (c.moveToNext()) {
+                String path = c.getString(c.getColumnIndex(MediaStore.Images.Media.DATA));// 路径
+                File parentFile = new File(path).getParentFile();
+                if (parentFile == null)
+                    continue;
+
+                String dir = parentFile.getAbsolutePath();
+                if (mDirs.contains(dir))//如果已经添加过
+                    continue;
+
+                mDirs.add(dir);//添加到保存目录的集合中
+                ImgFolderBean folderBean = new ImgFolderBean();
+                folderBean.setDir(dir);
+                folderBean.setFistImgPath(path);
+                if (parentFile.list() == null)
+                    continue;
+                int count = parentFile.list(new FilenameFilter() {
+                    @Override
+                    public boolean accept(File dir, String filename) {
+                        if (filename.endsWith(".jpeg") || filename.endsWith(".jpg") || filename.endsWith(".png")) {
+                            return true;
+                        }
+                        return false;
+                    }
+                }).length;
+
+                folderBean.setCount(count);
+                folders.add(folderBean);
+            }
+        } catch (Exception e) {
+            e.printStackTrace();
+        } finally {
+            if (c != null) {
+                c.close();
+            }
+        }
+
+        return folders;
+    }
+}

app/src/main/java/com/taifua/material/FileUtils.java

@@ -0,0 +1,115 @@
+package com.taifua.material;
+
+import android.os.Environment;
+
+import java.io.File;
+import java.text.SimpleDateFormat;
+import java.util.Calendar;
+
+public class FileUtils {
+
+    /**文档类型*/
+    public static final int TYPE_DOC = 0;
+    /**apk类型*/
+    public static final int TYPE_APK = 1;
+    /**压缩包类型*/
+    public static final int TYPE_ZIP = 2;
+
+
+    /**
+     * 判断文件是否存在
+     * @param path 文件的路径
+     * @return
+     */
+    public static boolean isExists(String path) {
+        File file = new File(path);
+        return file.exists();
+    }
+
+    public static int getFileType(String path) {
+        path = path.toLowerCase();
+        if (path.endsWith(".doc") || path.endsWith(".docx") || path.endsWith(".xls") || path.endsWith(".xlsx")
+                || path.endsWith(".ppt") || path.endsWith(".pptx")) {
+            return TYPE_DOC;
+        }else if (path.endsWith(".apk")) {
+            return TYPE_APK;
+        }else if (path.endsWith(".zip") || path.endsWith(".rar") || path.endsWith(".tar") || path.endsWith(".gz")) {
+            return TYPE_ZIP;
+        }else{
+            return -1;
+        }
+    }
+
+
+    /**通过文件名获取文件图标
+    public static int getFileIconByPath(String path){
+        path = path.toLowerCase();
+        int iconId = R.mipmap.unknow_file_icon;
+        if (path.endsWith(".txt")){
+            iconId = R.mipmap.type_txt;
+        }else if(path.endsWith(".doc") || path.endsWith(".docx")){
+            iconId = R.mipmap.type_doc;
+        }else if(path.endsWith(".xls") || path.endsWith(".xlsx")){
+            iconId = R.mipmap.type_xls;
+        }else if(path.endsWith(".ppt") || path.endsWith(".pptx")){
+            iconId = R.mipmap.type_ppt;
+        }else if(path.endsWith(".xml")){
+            iconId = R.mipmap.type_xml;
+        }else if(path.endsWith(".htm") || path.endsWith(".html")){
+            iconId = R.mipmap.type_html;
+        }
+        return iconId;
+    }
+     */
+
+    /**是否是图片文件*/
+    public static boolean isPicFile(String path){
+        path = path.toLowerCase();
+        if (path.endsWith(".jpg") || path.endsWith(".jpeg") || path.endsWith(".png")){
+            return true;
+        }
+        return false;
+    }
+
+
+    /** 判断SD卡是否挂载 */
+    public static boolean isSDCardAvailable() {
+        if (Environment.MEDIA_MOUNTED.equals(Environment
+                .getExternalStorageState())) {
+            return true;
+        } else {
+            return false;
+        }
+    }
+
+    /**
+     * 从文件的全名得到文件的拓展名
+     *
+     * @param filename
+     * @return
+     */
+    public static String getExtFromFilename(String filename) {
+        int dotPosition = filename.lastIndexOf('.');
+        if (dotPosition != -1) {
+            return filename.substring(dotPosition + 1, filename.length());
+        }
+        return "";
+    }
+    /**
+     * 读取文件的修改时间
+     *
+     * @param f
+     * @return
+     */
+    public static String getModifiedTime(File f) {
+        Calendar cal = Calendar.getInstance();
+        long time = f.lastModified();
+        SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
+        cal.setTimeInMillis(time);
+        // System.out.println("修改时间[2] " + formatter.format(cal.getTime()));
+        // 输出：修改时间[2] 2009-08-17 10:32:38
+        return formatter.format(cal.getTime());
+    }
+
+
+}

app/src/main/java/com/taifua/material/Images.java

@@ -0,0 +1,21 @@
+package com.taifua.material;
+
+import android.content.Context;
+import android.util.Log;
+
+import java.util.ArrayList;
+import java.util.List;
+
+public class Images {
+    private static List<ImgFolderBean> imgFolderList;
+    public  static List<String> imageThumbUrls = new ArrayList<>();
+    public static void init(Context context){
+        FileManager fileManager = FileManager.getInstance(context);
+        imgFolderList = fileManager.getImageFolders();
+        for (ImgFolderBean imgFolderBean:imgFolderList){
+            for (String s:fileManager.getImgListByDir(imgFolderBean.getDir()))
+            imageThumbUrls.add(s);
+        }
+        Log.d("图片总共有多少: ",""+imageThumbUrls.size());
+    }
+}

app/src/main/java/com/taifua/material/ImgFolderBean.java

@@ -0,0 +1,53 @@
+package com.taifua.material;
+
+public class ImgFolderBean {
+        /**当前文件夹的路径*/
+        private String dir;
+        /**第一张图片的路径，用于做文件夹的封面图片*/
+        private String fistImgPath;
+        /**文件夹名*/
+        private String name;
+        /**文件夹中图片的数量*/
+        private int count;
+
+        public ImgFolderBean(){}
+
+        public ImgFolderBean(String dir, String fistImgPath, String name, int count) {
+            this.dir = dir;
+            this.fistImgPath = fistImgPath;
+            this.name = name;
+            this.count = count;
+        }
+
+        public String getDir() {
+            return dir;
+        }
+
+        public void setDir(String dir) {
+            this.dir = dir;
+        }
+
+        public String getFistImgPath() {
+            return fistImgPath;
+        }
+
+        public void setFistImgPath(String fistImgPath) {
+            this.fistImgPath = fistImgPath;
+        }
+
+        public String getName() {
+            return name;
+        }
+
+        public void setName(String name) {
+            this.name = name;
+        }
+
+        public int getCount() {
+            return count;
+        }
+
+        public void setCount(int count) {
+            this.count = count;
+        }
+}

app/src/main/java/com/taifua/material/MainActivity.java

@@ -2,9 +2,7 @@
 
 import android.support.annotation.NonNull;
 import android.support.design.widget.BottomNavigationView;
-import android.support.design.widget.FloatingActionButton;
 import android.support.design.widget.NavigationView;
-import android.support.design.widget.Snackbar;
 import android.support.v4.app.Fragment;
 import android.support.v4.app.FragmentPagerAdapter;
 import android.support.v4.view.GravityCompat;
@@ -16,31 +14,32 @@
 import android.support.v7.widget.Toolbar;
 import android.view.Menu;
 import android.view.MenuItem;
-import android.view.View;
 import android.widget.Toast;
 
+/**
+ * 在这里把所有碎片和控件建好
+ * 然后再在fragment类里面写不同的页面
+ */
 public class MainActivity extends AppCompatActivity implements ViewPager.OnPageChangeListener
 {
 
     private DrawerLayout mDrawerLayout;
     private ViewPager viewPager;
     private NavigationView navView;
-    BottomNavigationView bottomNavigationView;
+    private BottomNavigationView bottomNavigationView;
     private PhotoFragment photoFragment = new PhotoFragment();
     private AlbumFragment albumFragment = new AlbumFragment();
     private AssistantFragment assistantFragment = new AssistantFragment();
     private ShareFragment shareFragment = new ShareFragment();
 
     @Override
-    public boolean onCreateOptionsMenu(Menu menu)
-    {
+    public boolean onCreateOptionsMenu(Menu menu) {
         getMenuInflater().inflate(R.menu.toolbar, menu);
         return true;
     }
 
     @Override
-    public boolean onOptionsItemSelected(MenuItem item)
-    {
+    public boolean onOptionsItemSelected(MenuItem item) {
         switch (item.getItemId())
         {
             case android.R.id.home:
@@ -56,8 +55,7 @@ public boolean onOptionsItemSelected(MenuItem item)
     }
 
     @Override
-    protected void onCreate(Bundle savedInstanceState)
-    {
+    protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
         Toolbar toolbar = findViewById(R.id.toolbar);