今天研究了大半天才把android 相機、相冊、剪切這三大塊搞清楚，中間被坑了好幾次，其實也是由於自己理解，查看了一些網上寫的，結果都沒能達到效果，還把自己弄得更亂，錯了很多次，終於有了收穫，最終把調用系統相機，獲取相冊，以及剪切的實現搞清楚了；
下面我們先上簡單的拍照實現代碼：
<span style="font-size:14px;">Intent camera = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(camera, CAMERA);</span> <span style="font-size:14px;"> @Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == CAMERA && resultCode == Activity.RESULT_OK && null != data){
Bundle bundle = data.getExtras();
//獲取相機返回的數據，並轉換爲圖片格式
Bitmap bitmap = (Bitmap) bundle.get("data");
ByteArrayOutputStream baos = null ;
try{
baos = new ByteArrayOutputStream();
bitmap.compress(Bitmap.CompressFormat.JPEG, 100, baos);
} finally {
try {
baos.flush();
baos.close();
} catch (IOException e) {
e.printStackTrace();
}
}
imageView.setImageBitmap(bitmap);
}</span>上面照相機有自己默認的存儲路徑，拍攝的照片將返回一個縮略圖。如果想訪問原始圖片，可以通過data.getExtras()能夠得到原始圖片位置。最終轉爲bitmap進行展示；
如果默認系統的沒有指定目標uri，data就有數據，如果指定uri，則data就沒有返回數據！需要獲取相應的uri，
<span style="font-size:14px;">uri = data.getData();</span>下面我們自定義照片圖片存儲的路徑：
<span style="font-size:14px;">Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
cameraFile = new File(Environment.getExternalStorageDirectory(),System.currentTimeMillis() + ".jpg");
intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri.fromFile(cameraFile));
startActivityForResult(intent, 1);</span>獲取相冊代碼：
<span style="font-size:14px;">Intent picture = new Intent(Intent.ACTION_GET_CONTENT);
picture.addCategory(Intent.CATEGORY_OPENABLE);
picture.setType("image/*");
startActivityForResult(picture, 2);</span>回調：
<span style="font-size:14px;">@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == Activity.RESULT_OK && null != data){
switch (requestCode) {
case 1:
uri = Uri.fromFile(cameraFile);
startPhotoZoom(this, uri,
3);
break;
case 2:
if (null != data) {//爲了取消選取不報空指針用的
uri = data.getData();
dataUri=uri;
if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.KITKAT) {
String path = PhotoClipperUtil.getPath(this, uri);
File f = new File(path);
dataUri = Uri.fromFile(f);
}
startPhotoZoom(this, uri,
3);
}
break;
case 3:
if(uri==null){
break;
}
try {
cropBitmap = MediaStore.Images.Media.getBitmap(MediaActivity.this.getContentResolver(), uri);
} catch (IOException e) {
e.printStackTrace();
}
if (cropBitmap != null) {
ByteArrayOutputStream baos = new ByteArrayOutputStream();
cropBitmap.compress(Bitmap.CompressFormat.JPEG, 100, baos);
imageView.setImageBitmap(cropBitmap);
}
break;
default:
break;
}
}</span>剪切代碼：
<span style="font-size:14px;">public void startPhotoZoom(Context context, Uri uri,int REQUE_CODE_CROP) {
Intent intent = new Intent("com.android.camera.action.CROP");
intent.setDataAndType(uri, "image/*");
// 下面這個crop=true是設置在開啓的Intent中設置顯示的VIEW可裁剪
intent.putExtra("crop", "true");
intent.putExtra("scale", true);// 去黑邊
intent.putExtra("scaleUpIfNeeded", true);// 去黑邊
// aspectX aspectY 是寬高的比例
intent.putExtra("aspectX", 1);//輸出是X方向的比例
intent.putExtra("aspectY", 1);
// outputX outputY 是裁剪圖片寬高
intent.putExtra("outputX", 500);//輸出X方向的像素
intent.putExtra("outputY", 500);//輸出Y方向的像素
intent.putExtra("outputFormat", Bitmap.CompressFormat.JPEG.toString());
intent.putExtra("noFaceDetection", true);
intent.putExtra(MediaStore.EXTRA_OUTPUT, uri);
intent.putExtra("return-data", false);//設置爲不返回數據
startActivityForResult(intent, REQUE_CODE_CROP);
}</span>public class PhotoClipperUtil {
@SuppressLint("NewApi")
public static String getPath(final Context context, final Uri uri) {
final boolean isKitKat = Build.VERSION.SDK_INT >= Build.VERSION_CODES.KITKAT;
// DocumentProvider
if (isKitKat && DocumentsContract.isDocumentUri(context, uri)) {
// ExternalStorageProvider
if (isExternalStorageDocument(uri)) {
final String docId = DocumentsContract.getDocumentId(uri);
final String[] split = docId.split(":");
final String type = split[0];
if ("primary".equalsIgnoreCase(type)) {
return Environment.getExternalStorageDirectory() + "/" + split[1];
}
}
// DownloadsProvider
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(context, contentUri, null, null);
}
// MediaProvider
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(context, contentUri, selection, selectionArgs);
}
}
// MediaStore (and general)
else if ("content".equalsIgnoreCase(uri.getScheme())) {
// Return the remote address
if (isGooglePhotosUri(uri))
return uri.getLastPathSegment();
return getDataColumn(context, uri, null, null);
}
// File
else if ("file".equalsIgnoreCase(uri.getScheme())) {
return uri.getPath();
}
return null;
}
/**
* Get the value of the data column for this Uri. This is useful for
* MediaStore Uris, and other file-based ContentProviders.
*
* @param context The context.
* @param uri The Uri to query.
* @param selection (Optional) Filter used in the query.
* @param selectionArgs (Optional) Selection arguments used in the query.
* @return The value of the _data column, which is typically a file path.
*/
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;
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is ExternalStorageProvider.
*/
public static boolean isExternalStorageDocument(Uri uri) {
return "com.android.externalstorage.documents".equals(uri.getAuthority());
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is DownloadsProvider.
*/
public static boolean isDownloadsDocument(Uri uri) {
return "com.android.providers.downloads.documents".equals(uri.getAuthority());
}
/**
* @param uri The Uri to check.
* @return Whether the Uri authority is MediaProvider.
*/
public static boolean isMediaDocument(Uri uri) {
return "com.android.providers.media.documents".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());
}
}
報錯提示你說沒有相應的權限，那麼就把權限加在androidManifest.xml：
<!-- 截圖權限-->
<uses-permission android:name="android.permission.READ_FRAMEBUFFER" />
<uses-permission android:name="android.permission.BLUETOOTH" />
<uses-permission android:name="android.permission.BLUETOOTH_ADMIN" />
<!-- 寫SD卡權限 -->
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
<uses-permission android:name="android.permission.ACCESS_LOCATION_EXTRA_COMMANDS" />
<uses-permission android:name="android.permission.WRITE_CONTACTS" />加上上面的權限代碼運行期啦，終於成功了；上面是大半天的研究成功希望能幫到大家；