/**
 * 1、實現(xiàn)原理:用戶打開相冊或相機(jī)選擇相片后,相片經(jīng)過壓縮并設(shè)置在控件上,圖片在本地sd卡存一份(如果有的話,沒有則內(nèi)部存儲,所以還
 * 需要判斷用戶是否掛載了sd卡),然后在服務(wù)器上存儲一份該圖片,當(dāng)下次再次啟動應(yīng)用時,會默認(rèn)去sd卡加載該圖片,如果本地沒有,再會去聯(lián)網(wǎng)請求
 * 2、使用了picasso框架以及自定義BitmapUtils工具類
 * 3、記得加上相關(guān)權(quán)限
 * <uses-permission android:name="android.permission.INTERNET"></uses-permission>
 <uses-permission android:name="android.permission.CAMERA"/>
 <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"></uses-permission>
 * */
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
  private ImageView iv;//要設(shè)置的頭像
  private Button btn_photo;//調(diào)用相冊按鈕
  private Button btn_camera;//調(diào)用相機(jī)按鈕
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    iv=(ImageView) findViewById(R.id.iv);
    btn_photo = (Button) findViewById(R.id.btn_photo);
    btn_camera = (Button) findViewById(R.id.btn_camera);
    btn_photo.setOnClickListener(this);
    btn_camera.setOnClickListener(this);
  }
  @Override
  public void onClick(View v) {
    switch (v.getId()) {
      case R.id.btn_photo://打開系統(tǒng)相冊
        Intent intent=new Intent(Intent.ACTION_PICK, MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
        startActivityForResult(intent,100);
        break;
      case R.id.btn_camera://打開系統(tǒng)相機(jī)
        Intent intent2=new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
        startActivityForResult(intent2,200);
        break;
    }
  }
  @RequiresApi(api = Build.VERSION_CODES.KITKAT)
  @Override
  protected void onActivityResult(int requestCode, int resultCode, Intent data) {
    super.onActivityResult(requestCode, resultCode, data);
    if(requestCode==100&&resultCode==RESULT_OK&&data!=null){//系統(tǒng)相冊
      Uri imageData = data.getData();
      String path=getPath(imageData);
      Bitmap bitmap = BitmapFactory.decodeFile(path);
      Bitmap bitmap1 = BitmapUtils.zoom(bitmap, iv.getWidth(), iv.getHeight());
      Bitmap bitmap2 = BitmapUtils.circleBitmap(bitmap1);
      //加載顯示
      iv.setImageBitmap(bitmap2);
      //bitmap圖片上傳到服務(wù)器......
      //bitmap圖片保存到本地
      saveImage(bitmap2);
    }else if(requestCode==200&&resultCode==RESULT_OK&&data!=null){//系統(tǒng)相機(jī)
      Bitmap bitmap = (Bitmap) data.getExtras().get("data");
      BitmapUtils.zoom(bitmap,iv.getWidth(),iv.getHeight());
      bitmap=BitmapUtils.circleBitmap(bitmap);
      //加載顯示
      iv.setImageBitmap(bitmap);
      //bitmap圖片上傳到服務(wù)器......
      //bitmap圖片保存到本地
      saveImage(bitmap);
    }
  }
  /**
   * 數(shù)據(jù)的存儲。（5種）
   * Bimap:內(nèi)存層面的圖片對象。
   *
   * 存儲--->內(nèi)存：
   *   BitmapFactory.decodeFile(String filePath);
   *   BitmapFactory.decodeStream(InputStream is);
   * 內(nèi)存--->存儲：
   *   bitmap.compress(Bitmap.CompressFormat.PNG,100,OutputStream os);
   */
  private void saveImage(Bitmap bitmap) {
    File filesDir;
    if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){//判斷sd卡是否掛載
      //路徑1：storage/sdcard/Android/data/包名/files
      filesDir = this.getExternalFilesDir("");
    }else{//手機(jī)內(nèi)部存儲
      //路徑：data/data/包名/files
      filesDir = this.getFilesDir();
    }
    FileOutputStream fos = null;
    try {
      File file = new File(filesDir,"icon.png");
      fos = new FileOutputStream(file);
      bitmap.compress(Bitmap.CompressFormat.PNG, 100,fos);
    } catch (FileNotFoundException e) {
      e.printStackTrace();
    }finally{
      if(fos != null){
        try {
          fos.close();
        } catch (IOException e) {
          e.printStackTrace();
        }
      }
    }
  }
  //如果本地有,就不需要再去聯(lián)網(wǎng)去請求
  private boolean readImage() {
    File filesDir;
    if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){//判斷sd卡是否掛載
      //路徑1：storage/sdcard/Android/data/包名/files
      filesDir = getExternalFilesDir("");
    }else{//手機(jī)內(nèi)部存儲
      //路徑：data/data/包名/files
      filesDir = getFilesDir();
    }
    File file = new File(filesDir,"icon.png");
    if(file.exists()){
      //存儲--->內(nèi)存
      Bitmap bitmap = BitmapFactory.decodeFile(file.getAbsolutePath());
      iv.setImageBitmap(bitmap);
      return true;
    }
    return false;
  }
  @RequiresApi(api = Build.VERSION_CODES.KITKAT)
  private String getPath(Uri uri) {
    int sdkVersion = Build.VERSION.SDK_INT;
    //高于4.4.2的版本
    if (sdkVersion >= 19) {
      Log.e("TAG", "uri auth: " + uri.getAuthority());
      if (isExternalStorageDocument(uri)) {
        String docId = DocumentsContract.getDocumentId(uri);
        String[] split = docId.split(":");
        String type = split[0];
        if ("primary".equalsIgnoreCase(type)) {
          return Environment.getExternalStorageDirectory() + "/" + split[1];
        }
      } else if (isDownloadsDocument(uri)) {
        final String id = DocumentsContract.getDocumentId(uri);
        final Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"),
            Long.valueOf(id));
        return getDataColumn(this, contentUri, null, null);
      } else if (isMediaDocument(uri)) {
        final String docId = DocumentsContract.getDocumentId(uri);
        final String[] split = docId.split(":");
        final String type = split[0];
        Uri contentUri = null;
        if ("image".equals(type)) {
          contentUri = MediaStore.Images.Media.EXTERNAL_CONTENT_URI;
        } else if ("video".equals(type)) {
          contentUri = MediaStore.Video.Media.EXTERNAL_CONTENT_URI;
        } else if ("audio".equals(type)) {
          contentUri = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
        }
        final String selection = "_id=?";
        final String[] selectionArgs = new String[]{split[1]};
        return getDataColumn(this, contentUri, selection, selectionArgs);
      } else if (isMedia(uri)) {
        String[] proj = {MediaStore.Images.Media.DATA};
        Cursor actualimagecursor = this.managedQuery(uri, proj, null, null, null);
        int actual_image_column_index = actualimagecursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
        actualimagecursor.moveToFirst();
        return actualimagecursor.getString(actual_image_column_index);
      }
    } else if ("content".equalsIgnoreCase(uri.getScheme())) {
      // Return the remote address
      if (isGooglePhotosUri(uri))
        return uri.getLastPathSegment();
      return getDataColumn(this, uri, null, null);
    }
    // File
    else if ("file".equalsIgnoreCase(uri.getScheme())) {
      return uri.getPath();
    }
    return null;
  }
  /**
   * uri路徑查詢字段
   *
   * @param context
   * @param uri
   * @param selection
   * @param selectionArgs
   * @return
   */
  public static String getDataColumn(Context context, Uri uri, String selection, String[] selectionArgs) {
    Cursor cursor = null;
    final String column = "_data";
    final String[] projection = {column};
    try {
      cursor = context.getContentResolver().query(uri, projection, selection, selectionArgs, null);
      if (cursor != null && cursor.moveToFirst()) {
        final int index = cursor.getColumnIndexOrThrow(column);
        return cursor.getString(index);
      }
    } finally {
      if (cursor != null)
        cursor.close();
    }
    return null;
  }
  private boolean isExternalStorageDocument(Uri uri) {
    return "com.android.externalstorage.documents".equals(uri.getAuthority());
  }
  public static boolean isDownloadsDocument(Uri uri) {
    return "com.android.providers.downloads.documents".equals(uri.getAuthority());
  }
  public static boolean isMediaDocument(Uri uri) {
    return "com.android.providers.media.documents".equals(uri.getAuthority());
  }
  public static boolean isMedia(Uri uri) {
    return "media".equals(uri.getAuthority());
  }
  /**
   * @param uri The Uri to check.
   * @return Whether the Uri authority is Google Photos.
   */
  public static boolean isGooglePhotosUri(Uri uri) {
    return "com.google.android.apps.photos.content".equals(uri.getAuthority());
  }
  /**
   * 判斷本地是否有該圖片,沒有則去聯(lián)網(wǎng)請求
   * */
  @Override
  protected void onResume() {
    super.onResume();
    if(readImage()){
      return;
    }
  }
}
//BitmapUtils工具類public class BitmapUtils { /**
   * 該方法用于將圖片進(jìn)行圓形處理
   * */  public static Bitmap circleBitmap(Bitmap source){    //默認(rèn)只對寬進(jìn)行處理    int width=source.getWidth();    Bitmap bitmap=Bitmap.createBitmap(width,width,Bitmap.Config.ARGB_8888);    Canvas canvas=new Canvas(bitmap);    Paint paint=new Paint();    //設(shè)置抗鋸齒    paint.setAntiAlias(true);    canvas.drawCircle(width/2,width/2,width/2,paint);    paint.setXfermode(new PorterDuffXfermode(PorterDuff.Mode.SRC_IN));    canvas.drawBitmap(source,0,0,paint);    return bitmap;  }  /**   * 該方法用于圖片壓縮處理,注意width、height參數(shù)的類型必須是float   * */  public static Bitmap zoom(Bitmap source,float width,float height){    Matrix matrix=new Matrix();    //圖片進(jìn)行壓縮處理    matrix.postScale(width/source.getWidth(),height/source.getHeight());    Bitmap bitmap = Bitmap.createBitmap(source, 0, 0, source.getWidth(), source.getHeight(), matrix, false);    return bitmap;  }}