示例:
public class GetPicActivity extends AppCompatActivity implements View.OnClickListener { private ImageView showImg; private Uri imageUri; public static final int TAKE_PHOTO = 1; public static final int CHOOSE_PHOTO = 2; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.activity_get_pic); initView(); } private void initView() { findViewById(R.id.getPicFromCamera).setOnClickListener(this); findViewById(R.id.getPicFromAblum).setOnClickListener(this); showImg = ((ImageView) findViewById(R.id.showImg)); } @Override public void onClick(View v) { switch (v.getId()) { case R.id.getPicFromCamera: getPicFromCamra(); break; case R.id.getPicFromAblum: getPicFromAblum(); break; } } private void getPicFromCamra() { // 創建file對象,用於存儲拍照後的圖片,通過getExternalCacheDir放在應用關聯緩存目錄 // 具體路徑是/sdcard/Android/data/<packeageName>/cache,android6.0讀寫sd卡爲 // 危險權限,需要運行時權限,而放應用關聯緩存不要 File outPutImage = new File(getExternalCacheDir(), "output_img.jpg"); try { if (outPutImage.exists()) { outPutImage.delete(); } outPutImage.createNewFile(); } catch (IOException e) { e.printStackTrace(); } if (Build.VERSION.SDK_INT >= 24) { // android7.0直接使用本地真實路徑uri是不安全的,通過FileProvider是一種特殊的內容提供器 // 可以選擇性的將封裝過的uri提供給外部,提高安全性。參數1:context對象。參數二:可以是任意的字符串, // 參數三:剛剛創建的file對象。注意這裏用到了內容提供者 imageUri = FileProvider.getUriForFile(GetPicActivity.this, "com.lvyequeen.test.day04.getpic", outPutImage); } else { // 獲取的是這張圖片的真是路徑 imageUri = Uri.fromFile(outPutImage); } // 用意圖打開相機 Intent intent = new Intent("android.media.action.IMAGE_CAPTURE"); // 指定圖片輸出地址 intent.putExtra(MediaStore.EXTRA_OUTPUT, imageUri); // 隱示意圖啓動 startActivityForResult(intent, TAKE_PHOTO); } /** * 通過相冊獲取圖片 */ private void getPicFromAblum() { // 判斷授予sd卡讀寫權限 if (ContextCompat.checkSelfPermission(GetPicActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) { ActivityCompat.requestPermissions(GetPicActivity.this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE}, 1); } else { openAblum(); } } /** * 打開相冊 */ private void openAblum() { Intent intent = new Intent("android.intent.action.GET_CONTENT"); intent.setType("image/*"); startActivityForResult(intent, CHOOSE_PHOTO); } @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { if (resultCode == RESULT_OK) { switch (requestCode) { case TAKE_PHOTO: try { Bitmap bitmap = BitmapFactory.decodeStream(getContentResolver().openInputStream(imageUri)); showImg.setImageBitmap(bitmap); } catch (FileNotFoundException e) { e.printStackTrace(); } break; case CHOOSE_PHOTO: if (Build.VERSION.SDK_INT >= 19) { // 4.4及以上系統,選取相冊中的圖片不再返回圖片真實的uri handleImageOnKitKat(data); } else { handleImagebeforeKitKat(data); } break; } } } @TargetApi(Build.VERSION_CODES.KITKAT) private void handleImageOnKitKat(Intent data) { String imagePath = null; Uri uri = data.getData(); // 如果uri是document類型,就通過讀取document id進行處理 if (DocumentsContract.isDocumentUri(this, uri)) { String docId = DocumentsContract.getDocumentId(uri); // 如果Uri的Authority是media格式的話,document id還需要進行解析,然後通過字符串 // 分割方式取出後半部分才能得到真正的數字id if ("com.android.providers.media.documents".equals(uri.getAuthority())) { String id = docId.split(":")[1]; String selection = MediaStore.Images.Media._ID + "=" + id; imagePath = getImagePath(MediaStore.Images.Media.EXTERNAL_CONTENT_URI, selection); } else if ("com.android.providers.downloads,documents".equals(uri.getAuthority())) { Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads.public_downloads"), Long.valueOf(docId)); imagePath = getImagePath(contentUri, null); } } else if ("content".equalsIgnoreCase(uri.getScheme())) { // 如果是content類型的uri,則使用普通方式處理 imagePath = getImagePath(uri, null); } else if ("file".equalsIgnoreCase(uri.getScheme())) { // 如果是file類型,直接獲取圖片路徑 imagePath = uri.getPath(); } displayImage(imagePath); } private void handleImagebeforeKitKat(Intent data) { Uri uri = data.getData(); String imagePath = getImagePath(uri, null); displayImage(imagePath); } /** * 獲取圖片真實路徑 * * @param uri * @param selection * @return */ private String getImagePath(Uri uri, String selection) { String path = null; Cursor cursor = getContentResolver().query(uri, null, selection, null, null); if (null != cursor) { if (cursor.moveToFirst()) { path = cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.DATA)); } cursor.close(); } return path; } /** * 根據圖片路徑顯示圖片 * * @param imagePath */ private void displayImage(String imagePath) { if (null != imagePath) { Bitmap b = BitmapFactory.decodeFile(imagePath); showImg.setImageBitmap(b); } else { Toast.makeText(this, "獲取圖片失敗", Toast.LENGTH_LONG).show(); } } /** * 處理權限的 * * @param requestCode * @param permissions * @param grantResults */ @Override public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) { switch (requestCode) { case 1: if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) { openAblum(); } else { Toast.makeText(this, "沒有權限啦~~", Toast.LENGTH_SHORT).show(); } break; } } }
注意事項:拍照上傳的時候用到了內容提供者要去清單文件中註冊,寫在application裏面的
<!--這裏註冊拍照那個內容提供者android:name爲固定值 android:authorities和FileProvider.getUriForFile 第二個參數值一樣 。meta-data指定uri共享路徑,創建@xml/file_paths文件 --> <provider android:authorities="com.lvyequeen.test.day04.getpic" android:name="android.support.v4.content.FileProvider" android:exported="false" android:grantUriPermissions="true"> <meta-data android:name="android.support.FILE_PROVIDER_PATHS" android:resource="@xml/file_paths" /> </provider>
在res文件夾下面創建一個xml文件夾,再在此文件夾下創建的file_path.xml
<?xml version="1.0" encoding="utf-8"?> <paths xmlns:android="http://schemas.android.com/apk/res/android"> <!--external-path用來指定uri共享的 name隨意填寫,path標示恭喜那個的具體路徑, 設置爲空則表示將整個sd卡進行共享。也可以寫定一個路徑 --> <external-path name="my_images" path="" /> </paths>