1. 一個小列子
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initView();
btnChoosePhoto.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
if (Build.VERSION.SDK_INT >= 23) {
if (ContextCompat.checkSelfPermission(MainActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {
ActivityCompat.requestPermissions(MainActivity.this,new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},1);
} else {
//跳轉到相冊
openAlbum();
}
} else {
//跳轉到相冊
openAlbum();
}
}
});
}
private void initView() {
btnChoosePhoto = findViewById(R.id.btn_choose_photo);
ivImage = findViewById(R.id.iv_image);
}
/**
* 打開相冊
*/
public void openAlbum() {
Intent intent = new Intent();
intent.setAction(Intent.ACTION_GET_CONTENT);
intent.setType("image/*");
startActivityForResult(intent, 1);
}
/**
* 打開設置界面
*/
public void openSetting() {
Intent intent = new Intent();
intent.setAction(Settings.ACTION_APPLICATION_DETAILS_SETTINGS);
intent.setData(Uri.fromParts("package", getApplication().getPackageName(), null));
startActivity(intent);
}
@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) {
openAlbum();
} else {
if (!ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this, Manifest.permission.WRITE_EXTERNAL_STORAGE)) {
openSetting();
}
}
break;
}
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch (requestCode) {
case 1:
if (resultCode == RESULT_OK) {
if (Build.VERSION.SDK_INT >= 19) {
//Android 4.4 以上的。返回的照片的Uri不是真實的Uri, 是封裝過的Uri。此時需要我們去解剖
handleImageOnKitKat(data);
} else if (Build.VERSION.SDK_INT < 19) {
//Android 4.4 以下的。
handleImageBeforeKitKat(data);
}
}
break;
}
}
/**
* 根據Uri來獲取到圖片對應的真實路徑
*
* @param uri
* @param selection
* @return
*/
public String getImagePath(Uri uri, String selection) {
String path = null;
Cursor cursor = getContentResolver().query(uri, null, selection, null, null);
if (cursor != null) {
if (cursor.moveToFirst()) {
path = cursor.getString(cursor.getColumnIndex(MediaStore.Images.Media.DATA));
}
cursor.close();
}
return path;
}
/**
* 展示圖片
*
* @param path
*/
public void displayImage(String path) {
if (path != null) {
Bitmap bitmap = BitmapFactory.decodeFile(path);
ivImage.setImageBitmap(bitmap);
} else {
//路徑爲空 很難過
}
}
@TargetApi(19)
public void handleImageOnKitKat(Intent data) {
String imagePath = null;
Uri uri = data.getData();
if (DocumentsContract.isDocumentUri(MainActivity.this, uri)) {
//如果是document類型的Uri,那麼通過document的id來處理
String documentId = DocumentsContract.getDocumentId(uri);
if ("com.android.providers.media.documents".equals(uri.getAuthority())) {
String id = documentId.split(":")[1];
//等價於下面兩句代碼
String [] array = documentId.split(":");
String id = array[1];
String selection = MediaStore.Images.Media._ID+"="+id;
imagePath = getImagePath(uri,selection);
}else if ("com.android.providers.downloads.documents".equals(uri.getAuthority())){
Uri contentUri = ContentUris.withAppendedId(Uri.parse("content://downloads/public_downloads"), Long.valueOf(documentId));
imagePath = getImagePath(contentUri,null);
}
}else if ("content".equalsIgnoreCase(uri.getScheme())){
//如果是content類型的uri那麼使用正常的uri
imagePath = getImagePath(uri,null);
}else if ("file".equalsIgnoreCase(uri.getScheme())){
//如果uri是file 那麼直接獲取文件的路徑
imagePath = uri.getPath();
}
displayImage(imagePath);
}
private void handleImageBeforeKitKat(Intent data) {
Uri uri = data.getData();
String imagePath = getImagePath(uri, null);
displayImage(imagePath);
}