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问题:
I'm working on an Android application which should be able to open a selected file from a specific folder.
I already tried this, but after selecting which application I want to open it, I got this message:
Impossible loading
After trying a lot of thread 1 and thread 2, I use these lines of code to do it:
Intent intent = new Intent();
intent.setAction(Intent.ACTION_VIEW);
intent.setDataAndType(Uri.parse("/mnt/sdcard/xxx/xxx/Pictures/xxx.jpg"), "image/*");
myContext.startActivity(intent);
How can I figure this out?
回答1:
Try the below code. I am using this code for opening a PDF file. You can use it for other files also.
File file = new File(Environment.getExternalStorageDirectory(),
"Report.pdf");
Uri path = Uri.fromFile(file);
Intent pdfOpenintent = new Intent(Intent.ACTION_VIEW);
pdfOpenintent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
pdfOpenintent.setDataAndType(path, "application/pdf");
try {
startActivity(pdfOpenintent);
}
catch (ActivityNotFoundException e) {
}
If you want to open files, you can change the setDataAndType(path, "application/pdf")
. If you want to open different files with the same intent, you can use Intent.createChooser(intent, "Open in...");
. For more information, look at How to make an intent with multiple actions.
回答2:
Use this code ,which helped me to open all types of files ...
private void openFile(File url) {
try {
Uri uri = Uri.fromFile(url);
Intent intent = new Intent(Intent.ACTION_VIEW);
if (url.toString().contains(".doc") || url.toString().contains(".docx")) {
// Word document
intent.setDataAndType(uri, "application/msword");
} else if (url.toString().contains(".pdf")) {
// PDF file
intent.setDataAndType(uri, "application/pdf");
} else if (url.toString().contains(".ppt") || url.toString().contains(".pptx")) {
// Powerpoint file
intent.setDataAndType(uri, "application/vnd.ms-powerpoint");
} else if (url.toString().contains(".xls") || url.toString().contains(".xlsx")) {
// Excel file
intent.setDataAndType(uri, "application/vnd.ms-excel");
} else if (url.toString().contains(".zip") || url.toString().contains(".rar")) {
// WAV audio file
intent.setDataAndType(uri, "application/x-wav");
} else if (url.toString().contains(".rtf")) {
// RTF file
intent.setDataAndType(uri, "application/rtf");
} else if (url.toString().contains(".wav") || url.toString().contains(".mp3")) {
// WAV audio file
intent.setDataAndType(uri, "audio/x-wav");
} else if (url.toString().contains(".gif")) {
// GIF file
intent.setDataAndType(uri, "image/gif");
} else if (url.toString().contains(".jpg") || url.toString().contains(".jpeg") || url.toString().contains(".png")) {
// JPG file
intent.setDataAndType(uri, "image/jpeg");
} else if (url.toString().contains(".txt")) {
// Text file
intent.setDataAndType(uri, "text/plain");
} else if (url.toString().contains(".3gp") || url.toString().contains(".mpg") ||
url.toString().contains(".mpeg") || url.toString().contains(".mpe") || url.toString().contains(".mp4") || url.toString().contains(".avi")) {
// Video files
intent.setDataAndType(uri, "video/*");
} else {
intent.setDataAndType(uri, "*/*");
}
intent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
context.startActivity(intent);
} catch (ActivityNotFoundException e) {
Toast.makeText(context, "No application found which can open the file", Toast.LENGTH_SHORT).show();
}
}
回答3:
Try this link. It might help you.
The link contains:
Example to show how to create an image chooser.
public class MainActivity extends Activity {
private Uri mImageCaptureUri;
private ImageView mImageView;
private static final int PICK_FROM_CAMERA = 1;
private static final int PICK_FROM_FILE = 2;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
final String [] items = new String [] {"From Camera", "From SD Card"};
ArrayAdapter<String> adapter = new ArrayAdapter<String> (this, android.R.layout.select_dialog_item, items);
AlertDialog.Builder builder = new AlertDialog.Builder(this);
builder.setTitle("Select Image");
builder.setAdapter( adapter, new DialogInterface.OnClickListener() {
public void onClick( DialogInterface dialog, int item) {
if (item == 0) {
Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
File file = new File(Environment.getExternalStorageDirectory(),
"tmp_avatar_" + String.valueOf(System.currentTimeMillis()) + ".jpg");
mImageCaptureUri = Uri.fromFile(file);
try {
intent.putExtra(android.provider.MediaStore.EXTRA_OUTPUT, mImageCaptureUri);
intent.putExtra("return-data", true);
startActivityForResult(intent, PICK_FROM_CAMERA);
}
catch (Exception e) {
e.printStackTrace();
}
dialog.cancel();
}
else {
Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, "Complete action using"), PICK_FROM_FILE);
}
}
} );
final AlertDialog dialog = builder.create();
mImageView = (ImageView) findViewById(R.id.iv_pic);
((Button) findViewById(R.id.btn_choose)).setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
dialog.show();
}
});
}
@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
if (resultCode != RESULT_OK)
return;
Bitmap bitmap = null;
String path = "";
if (requestCode == PICK_FROM_FILE) {
mImageCaptureUri = data.getData();
path = getRealPathFromURI(mImageCaptureUri); // From Gallery
if (path == null)
path = mImageCaptureUri.getPath(); // From File Manager
if (path != null)
bitmap = BitmapFactory.decodeFile(path);
}
else {
path = mImageCaptureUri.getPath();
bitmap = BitmapFactory.decodeFile(path);
}
mImageView.setImageBitmap(bitmap);
}
public String getRealPathFromURI(Uri contentUri) {
String [] proj = {MediaStore.Images.Media.DATA};
Cursor cursor = managedQuery( contentUri, proj, null, null,null);
if (cursor == null)
return null;
int column_index = cursor.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
return cursor.getString(column_index);
}
}
The code from my sample project above shows how to create a dialog that shows two options to select the image source. The first is from Camera, where the picture is taken directly from camera, and the second is from saved images on sdcard.
line 14: Define two image source options, from camera and from SD card.
line 16-48: Set up the image picker dialog.
line 22: If the user chooses to take a picture from the camera, create an intent to open the camera app with MediaStore.ACTION_IMAGE_CAPTURE action.
line 23: Create a temporary file to hold the image from the camera.
line 24: Get the URI of the temporary file
line 39: If the user chooses to select an image from the SD card, start the intent to open the image chooser dialog. The image chooser dialog will display list File Manager (if it exists) apps and the default gallery app.
line 55: Show the image picker dialog.
line 61: Override the onActivityResult method to handle the selected image.
line 67: If the user selects an image from the SD card, get the URI of the selected image (line 68)
line 69: Assume the user selects the image from the SD card using the gallery app. The URI from the gallery app does not give the real path to the selected image, so it has to be resolved on the content provider. Method getRealPathFromURI used to resolve the real path from the URI.
line 71: If the path is null, assume the user selects the image using the File Manager app. The File Manager app returns different information than the gallery app. To get the real path to the selected image, use getImagePath method from the URI (line 72).
line 75: Get the bitmap.
line 77: If the user chooses to take a picture from the camera, get the real path of the temporary file that was previously defined on line 24-25.
line 78: Get the bitmap.
line 81: Display the bitmap on the image view.
回答4:
Download source code from here (https://deepshikhapuri.wordpress.com/2017/04/24/open-pdf-file-from-sdcard-in-android-programmatically/)
activity_main.xml:
<?xml version=”1.0″ encoding=”utf-8″?>
<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”
android:background=”#efefef”>
<ListView
android:layout_width=”match_parent”
android:id=”@+id/lv_pdf”
android:divider=”#efefef”
android:layout_marginLeft=”10dp”
android:layout_marginRight=”10dp”
android:layout_marginTop=”10dp”
android:layout_marginBottom=”10dp”
android:dividerHeight=”5dp”
android:layout_height=”wrap_content”>
</ListView>
</RelativeLayout>
MainActivity.java:
package com.pdffilefromsdcard;
import android.Manifest;
import android.app.ProgressDialog;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.os.Environment;
import android.support.v4.app.ActivityCompat;
import android.support.v4.content.ContextCompat;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ListView;
import android.widget.Toast;
import java.io.File;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
public class MainActivity extends AppCompatActivity {
ListView lv_pdf;
public static ArrayList<File> fileList = new ArrayList<File>();
PDFAdapter obj_adapter;
public static int REQUEST_PERMISSIONS = 1;
boolean boolean_permission;
File dir;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
init();
}
private void init() {
lv_pdf = (ListView) findViewById(R.id.lv_pdf);
dir = new File(Environment.getExternalStorageDirectory().getAbsolutePath());
fn_permission();
lv_pdf.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int i, long l) {
Intent intent = new Intent(getApplicationContext(), PdfActivity.class);
intent.putExtra(“position”, i);
startActivity(intent);
Log.e(“Position”, i + “”);
}
});
}
public ArrayList<File> getfile(File dir) {
File listFile[] = dir.listFiles();
if (listFile != null && listFile.length > 0) {
for (int i = 0; i < listFile.length; i++) {
if (listFile[i].isDirectory()) {
getfile(listFile[i]);
} else {
boolean booleanpdf = false;
if (listFile[i].getName().endsWith(“.pdf”)) {
for (int j = 0; j < fileList.size(); j++) {
if (fileList.get(j).getName().equals(listFile[i].getName())) {
booleanpdf = true;
} else {
}
}
if (booleanpdf) {
booleanpdf = false;
} else {
fileList.add(listFile[i]);
}
}
}
}
}
return fileList;
}
private void fn_permission() {
if ((ContextCompat.checkSelfPermission(getApplicationContext(), Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED)) {
if ((ActivityCompat.shouldShowRequestPermissionRationale(MainActivity.this, android.Manifest.permission.READ_EXTERNAL_STORAGE))) {
} else {
ActivityCompat.requestPermissions(MainActivity.this, new String[]{android.Manifest.permission.READ_EXTERNAL_STORAGE},
REQUEST_PERMISSIONS);
}
} else {
boolean_permission = true;
getfile(dir);
obj_adapter = new PDFAdapter(getApplicationContext(), fileList);
lv_pdf.setAdapter(obj_adapter);
}
}
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
super.onRequestPermissionsResult(requestCode, permissions, grantResults);
if (requestCode == REQUEST_PERMISSIONS) {
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
boolean_permission = true;
getfile(dir);
obj_adapter = new PDFAdapter(getApplicationContext(), fileList);
lv_pdf.setAdapter(obj_adapter);
} else {
Toast.makeText(getApplicationContext(), “Please allow the permission”, Toast.LENGTH_LONG).show();
}
}
}
}
activity_pdf.xml:
<?xml version=”1.0″ encoding=”utf-8″?>
<LinearLayout xmlns:android=”http://schemas.android.com/apk/res/android”
android:layout_width=”match_parent”
android:background=”#ffffff”
android:layout_height=”match_parent”
android:orientation=”vertical”>
<com.github.barteksc.pdfviewer.PDFView
android:id=”@+id/pdfView”
android:layout_margin=”10dp”
android:layout_width=”match_parent”
android:layout_height=”match_parent” />
</LinearLayout>
PdfActivity.java:
package com.pdffilefromsdcard;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;
import com.github.barteksc.pdfviewer.PDFView;
import com.github.barteksc.pdfviewer.listener.OnLoadCompleteListener;
import com.github.barteksc.pdfviewer.listener.OnPageChangeListener;
import com.github.barteksc.pdfviewer.scroll.DefaultScrollHandle;
import com.shockwave.pdfium.PdfDocument;
import java.io.File;
import java.util.List;
public class PdfActivity extends AppCompatActivity implements OnPageChangeListener,OnLoadCompleteListener {
PDFView pdfView;
Integer pageNumber = 0;
String pdfFileName;
String TAG=”PdfActivity”;
int position=-1;
@Override
protected void onCreate(@Nullable Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_pdf);
init();
}
private void init(){
pdfView= (PDFView)findViewById(R.id.pdfView);
position = getIntent().getIntExtra(“position”,-1);
displayFromSdcard();
}
private void displayFromSdcard() {
pdfFileName = MainActivity.fileList.get(position).getName();
pdfView.fromFile(MainActivity.fileList.get(position))
.defaultPage(pageNumber)
.enableSwipe(true)
.swipeHorizontal(false)
.onPageChange(this)
.enableAnnotationRendering(true)
.onLoad(this)
.scrollHandle(new DefaultScrollHandle(this))
.load();
}
@Override
public void onPageChanged(int page, int pageCount) {
pageNumber = page;
setTitle(String.format(“%s %s / %s”, pdfFileName, page + 1, pageCount));
}
@Override
public void loadComplete(int nbPages) {
PdfDocument.Meta meta = pdfView.getDocumentMeta();
printBookmarksTree(pdfView.getTableOfContents(), “-“);
}
public void printBookmarksTree(List<PdfDocument.Bookmark> tree, String sep) {
for (PdfDocument.Bookmark b : tree) {
Log.e(TAG, String.format(“%s %s, p %d”, sep, b.getTitle(), b.getPageIdx()));
if (b.hasChildren()) {
printBookmarksTree(b.getChildren(), sep + “-“);
}
}
}
}
Thanks!
回答5:
Try the following code.
File file = new File(path); // path = your file path
lastSlash = file.toString().lastIndexOf('/');
if (lastSlash >= 0)
{
fileName = url.toString().substring(lastSlash + 1);
}
if (fileName.endsWith("pdf"))
{
mimeType = "application/pdf";
}
else
{
mimeType = MimeTypeMap.getSingleton().getMimeTypeFromExtension
(MimeTypeMap.getFileExtensionFromUrl(path));
}
Uri uri_path = Uri.fromFile(file);
Intent intent = new Intent(android.content.Intent.ACTION_VIEW);
intent.putExtra(PATH, path);
intent.putExtra(MIMETYPE, mimeType);
intent.setType(mimeType);
intent.setDataAndType(uri_path, mimeType);
startActivity(intent);
回答6:
directly you can use this code it will open all type of files
Intent sharingIntent = new Intent(Intent.ACTION_VIEW);
Uri screenshotUri = Uri.fromFile(your_file);
sharingIntent.setType("image/png");
sharingIntent.putExtra(Intent.EXTRA_STREAM, screenshotUri);
String type = MimeTypeMap.getSingleton().getMimeTypeFromExtension(MimeTypeMap.getFileExtensionFromUrl(screenshotUri.toString()));
sharingIntent.setDataAndType(screenshotUri, type == null ? "text/plain" : type);
startActivity(Intent.createChooser(sharingIntent, "Share using"));
回答7:
You can try this
File file = new File(filePath);
MimeTypeMap map = MimeTypeMap.getSingleton();
String ext = MimeTypeMap.getFileExtensionFromUrl(file.getName());
String type = map.getMimeTypeFromExtension(ext);
if (type == null)
type = "*/*";
Intent intent = new Intent(Intent.ACTION_VIEW);
Uri data = Uri.fromFile(file);
intent.setDataAndType(data, type);
startActivity(intent);