Android 图片选择器

图片选择器，遍历系统所有图片并显示，点击查看大图，长按选中，并将结果返回

字体颜色res/color建立text_selecor.xml

 <selector xmlns:android="http://schemas.android.com/apk/res/android">
     <item android:color="@android:color/white" android:state_enabled="true"/>
     <item android:color="@android:color/darker_gray" android:state_enabled="false"/>
 </selector>

text_selector.xml

图片选择按钮

 <selector xmlns:android="http://schemas.android.com/apk/res/android">
     <item android:state_checked="true" android:drawable="@mipmap/sel_check"/>
     <item android:state_checked="false" android:drawable="@mipmap/sel_nor"/>
 </selector>

item_selector

遍历之后将所有图片显示

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
     android:layout_width="match_parent"
     android:background="@android:color/background_dark"
     android:layout_height="match_parent">
     <ImageView
         android:id="@+id/iv_img"
         android:layout_width="match_parent"
         android:layout_height="match_parent"
         android:scaleType="centerCrop"
         android:layout_margin="10dp"
         android:src="@mipmap/camera"/>
     <CheckBox
         android:id="@+id/cb_btn"
         android:layout_margin="15dp"
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:layout_alignParentRight="true"
         android:button="@drawable/item_selector"/>

 </RelativeLayout>

item_image.xml

 <LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
     android:id="@+id/activity_main"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     android:orientation="vertical"
     tools:context="com.example.lesson10_picselectordemo.MainActivity">

     <RelativeLayout
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:background="@android:color/holo_blue_dark"
         android:padding="10dp">

         <TextView
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:layout_centerHorizontal="true"
             android:text="图片选择"
             android:textColor="@android:color/white"
             android:textSize="18sp" />

         <TextView
             android:id="@+id/tv_finish"
             android:layout_width="wrap_content"
             android:layout_height="wrap_content"
             android:layout_alignParentRight="true"
             android:enabled="false"
             android:text="完成"
             android:textColor="@color/text_selector" />

     </RelativeLayout>

     <GridView
         android:id="@+id/gv_image"
         android:layout_width="match_parent"
         android:layout_height="wrap_content"
         android:numColumns="4"/>
 </LinearLayout>

activity_main.xml

适配器，当适配数据类型不确定时，可以使用泛型.继承BaseAdapter都要重写那几个方法，这里将他们抽出来

 /**
  * 适配数据类型不确定，可以使用泛型
  * 也可以是使用extends限定泛型，比如接口IGetName有个getName()方法，只要T继承IGetName实现方法，就可以使用该方法
  * Created by Administrator on 2016/10/24 0024.
  */

 public abstract class ListItemAdapter<T> extends BaseAdapter {

     //适配器需要上下文，数据
     //使用ptotected修饰符，使子类也可以用
     protected Context mContext;
     protected List<T> mList;

     public ListItemAdapter(Context mContext,List<T> mList){
         this.mContext = mContext;
         this.mList = mList;
     }

     @Override
     public int getCount() {
         return mList.size();
     }

     @Override
     public T getItem(int position) {
         return mList.get(position);
     }

     @Override
     public long getItemId(int position) {
         return position;
     }
 }

ListItemAdapter.java

然后ImageAdapter只要继承ListItemAdapter重写getView即可

 public class ImageAdapter extends ListItemAdapter<File> {

     private boolean select = false;

     public void open(int position){
         select = true;
         booleanArray.put(position,true);
         if(onImageCheckedListener != null){
             onImageCheckedListener.onImageChecked(true);
         }
         this.notifyDataSetChanged();
     }

     public void close(){
         select = false;
         booleanArray.clear();
         this.notifyDataSetChanged();
     }

     public ImageAdapter(Context mContext, List<File> mList) {
         super(mContext, mList);
     }

     @Override
     public int getCount() {
         //多出来的第一张为照相机，点击进入照相机
         return super.getCount()+1;
     }

     /**
      * 这里布局重用，使用checkbox会导致很多问题，
      * 勾选了一个，下拉之后发现下面也被勾选了一个
      * 这时，我们可以使用HashMap<Integer,Boolean>,是否被勾选
      *
      * 这里推荐使用另外一个类SparseBooleanArray
      *
      * @param position
      * @param convertView
      * @param parent
      * @return
      */
     SparseBooleanArray booleanArray = new SparseBooleanArray();

     public SparseBooleanArray getBooleanArray() {
         return booleanArray;
     }

     @Override
     public View getView(final int position, View convertView, ViewGroup parent) {
         ViewHolder viewHolder;
         if(convertView == null){
             convertView = View.inflate(mContext,R.layout.item_image,null);
             viewHolder = new ViewHolder(convertView);
             convertView.setTag(viewHolder);
         }

         viewHolder = (ViewHolder) convertView.getTag();

         if(position == 0){
             //照相机
             viewHolder.iv_img.setImageResource(R.mipmap.camera);
             viewHolder.cb_btn.setVisibility(View.GONE);
         }else{

             //设置图片
             viewHolder.iv_img.setImageURI(Uri.fromFile(mList.get(position - 1)));

             if(select) {
                 viewHolder.cb_btn.setVisibility(View.VISIBLE);
                 //是否需要勾选呢？
                 Boolean b = booleanArray.get(position);
                 if (b == null || b == false) {
                     viewHolder.cb_btn.setChecked(false);
                 } else {
                     viewHolder.cb_btn.setChecked(true);
                 }

                 //checkbox不能设置onCheckChange监听，因为上面setChecked导致下面isCheck也会跟着变化
             /*viewHolder.cb_btn.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
                 @Override
                 public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
                     booleanArray.put(position,isChecked);
                 }
             });*/
                 viewHolder.cb_btn.setOnClickListener(new View.OnClickListener() {
                     @Override
                     public void onClick(View v) {
                         //position有可能不存在，为空，这里必须给Boolean
                         Boolean b = booleanArray.get(position);
                         if (b == null || b == false) {
                             b = true;
                         } else {
                             b = false;
                         }
                         booleanArray.put(position, b);

                         //判断所有boolean ,如果没有一个true,则关闭
                         for (int i = 0; i <booleanArray.size() ; i++) {
                             //i一定存在，所以可以给boolean
                             boolean isChecked = booleanArray.get(booleanArray.keyAt(i));
                             if(isChecked){
                                 //说明有被勾选的值
                                 if(onImageCheckedListener != null){
                                     onImageCheckedListener.onImageChecked(true);
                                 }
                                 return;
                             }
                         }
                         //没有被勾选的值，
                         if(onImageCheckedListener != null)
                             onImageCheckedListener.onImageChecked(false);
                         //关闭
                         close();
                     }
                 });
             }else {
                 viewHolder.cb_btn.setVisibility(View.GONE);
             }
         }
         return convertView;
     }

     //回调方法
     //写在需要执行方法的地方
     //实现，在需要返回的地方
     public interface  OnImageCheckedListener{
         void onImageChecked(boolean b);
     }

     private OnImageCheckedListener onImageCheckedListener;

     //alt + insert
     public void setOnImageCheckedListener(OnImageCheckedListener onImageCheckedListener) {
         this.onImageCheckedListener = onImageCheckedListener;
     }

     class ViewHolder{
         ImageView iv_img;
         CheckBox cb_btn;

         public ViewHolder(View convertView){

             iv_img = (ImageView) convertView.findViewById(R.id.iv_img);
             int width = mContext.getResources().getDisplayMetrics().widthPixels / 4 -2;
             RelativeLayout.LayoutParams params = new RelativeLayout.LayoutParams(width,width);
             iv_img.setLayoutParams(params);
             cb_btn = (CheckBox) convertView.findViewById(R.id.cb_btn);
         }
     }
 }

ImageAdapter.java

点击查看大图

 public class ShowBigImage extends AppCompatActivity{

     @Override
     protected void onCreate(@Nullable Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         ImageView img = new ImageView(this);

         File file = (File) getIntent().getSerializableExtra("img");
         img.setImageURI(Uri.fromFile(file));
         setContentView(img);
     }
 }

ShowBigImage.java

 public class MainActivity extends AppCompatActivity implements AdapterView.OnItemClickListener, AdapterView.OnItemLongClickListener, ImageAdapter.OnImageCheckedListener, View.OnClickListener {
     private static final int CAMERA_CODE = 1;
     //SD卡所有图片
     List<File> filesList = new ArrayList<>();

     ProgressDialog dialog;

     GridView gv_image;
     TextView tv_finish;
     ImageAdapter adapter;

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);

         //加载数据
         loadData();
         //初始化视图
         initView();

     }

     private void initView() {
         gv_image = (GridView) findViewById(R.id.gv_image);
         tv_finish = (TextView) findViewById(R.id.tv_finish);
         adapter = new ImageAdapter(this,filesList);
         tv_finish.setOnClickListener(this);
         adapter.setOnImageCheckedListener(this);
         gv_image.setAdapter(adapter);
         //点击图片查看大图
         gv_image.setOnItemClickListener(this);
         //长按选择图片
         gv_image.setOnItemLongClickListener(this);
     }

     public ProgressDialog showDialog(){
         //显示Dialog
         dialog = new ProgressDialog(this);
         dialog.setTitle("加载数据");
         dialog.setMessage("正在加载数据，请稍等...");
         dialog.setProgressStyle(ProgressDialog.STYLE_SPINNER);
         dialog.show();

         return dialog;
     }

     public void loadData(){
         dialog = showDialog();

         //数据加载不能阻塞UI
         //在子线程中加载
         new Thread(){
             @Override
             public void run() {
                 super.run();
                 //开始递归遍历SD卡根目录
                 /*public static File getExternalStorageDirectory() {
                     throwIfUserRequired();
                     return sCurrentUser.getExternalDirs()[0];//获取第0张SD卡如果想要其他SD卡，只要重写这个方法即可
                 }*/
                 File SDDir = Environment.getExternalStorageDirectory();
                 getFiles(SDDir);

                 //数据加载完毕，要关闭Dialog
                 runOnUiThread(new Runnable() {
                     @Override
                     public void run() {
                         dialog.dismiss();
                         //刷新适配器
                         adapter.notifyDataSetChanged();
                     }
                 });
             }
         }.start();
     }

     public void getFiles(File dir){
         File[] files = dir.listFiles();

         if(files == null){
             return;
         }

         //开始遍历
         for (File file : files) {
             if(file.isDirectory()){
                 getFiles(file);
             }else{
                 if(file.getName().endsWith("jpg") || file.getName().endsWith("png")){
                     filesList.add(file);
                 }
             }
         }
     }

     File cameraFile;
     @Override
     public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
         //点击查看大图
         if(position == 0){
             //getAbsolutePath默认没有带"/"
             cameraFile = new File(Environment.getExternalStorageDirectory().getAbsolutePath()+"/DCIM/"+System.currentTimeMillis()+".png");
             //打开照相机
             Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
             //图片保存位置
             intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(cameraFile));
             startActivityForResult(intent,CAMERA_CODE);

         }else{
             //打开大图
             File file = filesList.get(position - 1);
             //带数据点开大图
             Intent intent = new Intent(this,ShowBigImage.class);
             intent.putExtra("img",file);
             startActivity(intent);
         }

     }

     @Override
     protected void onActivityResult(int requestCode, int resultCode, Intent data) {
         super.onActivityResult(requestCode, resultCode, data);
         if(requestCode == requestCode && resultCode == RESULT_OK){
             //照相机的图片永远放在第一个
             filesList.add(0,cameraFile);
             adapter.notifyDataSetChanged();
         }
     }

     @Override
     public boolean onItemLongClick(AdapterView<?> parent, View view, int position, long id) {
         //长按选择图片
         //照相机不能长按
         if(position == 0){
             return false;
         }else{
             adapter.open(position);
         }

         return true;
     }

     @Override
     public void onImageChecked(boolean b) {
         //b代表适配器中有没有被勾选的值
         tv_finish.setEnabled(b);
     }

     @Override
     public void onClick(View v) {
         //选择的图片
         //不能使用泛型，ArrayList才实现了序列化，List没有实现
         ArrayList<File> resultList = new ArrayList<>();
         //点击完成，带参返回
         //需要知道哪些数据被选中
         //通过是是适配器中的boolArray的为true的选中项来加载file
         SparseBooleanArray booleanArray = adapter.getBooleanArray();
         for (int i = 0; i <booleanArray.size() ; i++) {
             boolean isSelected = booleanArray.get(booleanArray.keyAt(i));
             if(isSelected){
                 int position = booleanArray.keyAt(i);
                 //剔除掉第一张照相机图片
                 resultList.add(filesList.get(position-1));
             }
         }
         Intent intent = new Intent();
         intent.putExtra("list",resultList);
         //返回数据
         setResult(RESULT_OK,intent);
         finish();
     }
 }

MainActivity.java

AndroidManifest.xml设置权限，注册活动

设置intent-filter <action> 并设置出口exported

 <manifest xmlns:android="http://schemas.android.com/apk/res/android"
     package="com.example.lesson10_picselectordemo">

     <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

     <application android:allowBackup="true" android:icon="@mipmap/ic_launcher"
         android:label="@string/app_name" android:supportsRtl="true" android:theme="@style/AppTheme">
         <activity android:name=".MainActivity"
             android:exported="true">
             <intent-filter>
                 <action android:name="SelectPicture"/>
                 <action android:name="android.intent.action.MAIN" />
                 <category android:name="android.intent.category.DEFAULT"/>
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>
         <activity android:name=".ShowBigImage"/>
     </application>

 </manifest>

AndroidManifest.xml

测试类

点击Buttong,打开图片选择器

 <RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
     xmlns:tools="http://schemas.android.com/tools"
     android:id="@+id/activity_main"
     android:layout_width="match_parent"
     android:layout_height="match_parent"
     tools:context="com.example.lesson10_picselectordemotest.MainActivity">

     <Button
         android:layout_width="wrap_content"
         android:layout_height="wrap_content"
         android:onClick="toPicSelectorDemo"
         android:layout_centerInParent="true"
         android:text="图片选择器启动另一个Module" />
 </RelativeLayout>

activity_main.xml

 public class MainActivity extends AppCompatActivity {

     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         setContentView(R.layout.activity_main);
     }

     public void toPicSelectorDemo(View v){

          startActivityForResult(new Intent("SelectPicture"),1);
     }

     @Override
     protected void onActivityResult(int requestCode, int resultCode, Intent data) {
         super.onActivityResult(requestCode, resultCode, data);
         if(resultCode == RESULT_OK){
             ArrayList<File> file = (ArrayList<File>) data.getSerializableExtra("list");
             Toast.makeText(this,file.toString(),Toast.LENGTH_SHORT).show();
         }
     }
 }

MainActivity.java