我的活动
public class CommonChattingAttachmentActivity extends BaseActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_common_chatting_attachment);
lv= (ListView) findViewById(R.id.Listview_common);
commonchat = findViewById(R.id.commonchat);
functions = findViewById(R.id.functions);
//times=(TextView) findViewById(R.id.times);
imglocation=(ImageView) findViewById(R.id.imglocation);
lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
@Override
public void onItemClick(AdapterView<?> adapterView, View view, int position, long l) {
CommonChat items = (CommonChat) lv.getItemAtPosition(position);
view.setBackgroundColor(Color.parseColor("#e5e5e5"));
change2();
}
});
lv.setOnItemLongClickListener(new AdapterView.OnItemLongClickListener() {
@Override
public boolean onItemLongClick(AdapterView<?> adapterView, View view, int position, long l) {
CommonChat item = (CommonChat) lv.getItemAtPosition(position);
view.setBackgroundColor(Color.parseColor("#a9a9a9"));
change1();
h=item.getDescription();
onclick();
// onitemclick();
return true;
}
});
imgcopy = (ImageView) functions.findViewById(R.id.imagecopy);
imgdelete=(ImageView) functions.findViewById(R.id.imgdelete);
//INITIALIZE REALM
realm=Realm.getDefaultInstance();
setAdapter();
displayInputDialog();
// timed();
imgcam=(ImageView)findViewById(R.id.imgcam);
imgallery=(ImageView) findViewById(R.id.imggallery);
imgattach=(ImageView) findViewById(R.id.imgattach);
imgallery.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
galleryIntent();
}
});
imgcam.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
cameraIntent();
}
});
imgattach.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
selectImage();
}
});
imglocation.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Intent i = new Intent(CommonChattingAttachmentActivity.this, MapsActivity.class);
startActivityForResult(i, 1);
}
});
}
public void onclick()
{
imgcopy.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
ClipboardManager cm = (ClipboardManager) getApplicationContext().getSystemService(CLIPBOARD_SERVICE);
cm.setText(h);
}
});
imgdelete.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
String type = h;
final RealmResults<CommonChat> students = realm.where(CommonChat.class).findAll();
CommonChat CommonChat = students.where().equalTo("description", type).findFirst();
if (CommonChat != null) {
if (!realm.isInTransaction()) {
realm.beginTransaction();
}
CommonChat.removeFromRealm();
realm.commitTransaction();
}
}
//final int position2 = holder.getAdapterPosition();
});
}
public void setAdapter()
{
lv= (ListView) findViewById(R.id.Listview_common);
final CommonChatRealmHelper helper=new CommonChatRealmHelper(realm);
helper.retrieveFromDB();
CCAA adapter=new CCAA(CommonChattingAttachmentActivity.this,helper.justRefresh());
lv.setAdapter(adapter);
adapter.notifyDataSetChanged();
realmChangeListener=new RealmChangeListener() {
@Override
public void onChange() {
CCAA adapter=new CCAA(CommonChattingAttachmentActivity.this,helper.justRefresh());
lv.setAdapter(adapter);
adapter.notifyDataSetChanged();
}
};
realm.addChangeListener(realmChangeListener);
}
//DISPLAY INPUT DIALOG
public void displayInputDialog()
{
//EDITTEXTS
descEditTxt= (EditText) findViewById(R.id.editwrite);
ImageView fab = (ImageView) findViewById(R.id.send);
//SAVE
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
String desc = descEditTxt.getText().toString();
CommonChat s = new CommonChat();
s.setDescription(desc);
CommonChatRealmHelper helper = new CommonChatRealmHelper(realm);
if (helper.save(s)) {
descEditTxt.setText("");
setAdapter();
// addImages();
}
else {
Toast.makeText(CommonChattingAttachmentActivity.this, "Invalid Data", Toast.LENGTH_SHORT).show();
}
}
});
}
public void cameraIntent() {
Intent intent = new Intent(android.provider.MediaStore.ACTION_IMAGE_CAPTURE);
startActivityForResult(intent, REQUEST_CAMERA);
//intent.putExtra("camera",REQUEST_CAMERA);
}
public void galleryIntent() {
Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);//
startActivityForResult(Intent.createChooser(intent, "Select File"), SELECT_FILE);
}
public void SaveMapData(String result1,String result2) {
try {
Realm realm = Realm.getDefaultInstance();
realm.beginTransaction();
CommonChat s = realm.createObject(CommonChat.class);
s.setLatitude(result1);
s.setLongitude(result2);
realm.commitTransaction();
realm.close();
CommonChatRealmHelper helper = new CommonChatRealmHelper(realm);
if (helper.save(s)) {
setAdapter();
}
else
{
Toast.makeText(CommonChattingAttachmentActivity.this, "Invalid Data", Toast.LENGTH_SHORT).show();
}
// Log.d("path", result);
Log.d("working realm", "yes....");
Toast.makeText(getApplicationContext(),"Set Image URL"+result,Toast.LENGTH_LONG).show();
}
catch (Exception ex){
Toast.makeText(getApplicationContext(),"Nope its not done",Toast.LENGTH_LONG).show();
}
}
public void selectImage() {
final CharSequence[] items = { "Take Photo", "Choose from Library","Camera Video","Gallery Video","Current Location",
"Cancel" };
AlertDialog.Builder builder = new AlertDialog.Builder(CommonChattingAttachmentActivity.this);
builder.setTitle("Add Photo!");
builder.setItems(items, new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface dialog, int item) {
boolean result=Utility.checkPermission(CommonChattingAttachmentActivity.this);
if (items[item].equals("Take Photo")) {
userChoosenTask="Take Photo";
if(result)
cameraIntent();
} else if (items[item].equals("Choose from Library")) {
userChoosenTask="Choose from Library";
if(result)
galleryIntent();
}
else if (items[item].equals("Camera Video")) {
userChoosenTask="Camera Video";
if(result)
startRecording();
}
else if (items[item].equals("Gallery Video")) {
userChoosenTask="Gallery Video";
if(result)
CaptureVideoFromGallery();
}
else if (items[item].equals("Current Location")) {
userChoosenTask="Current Location";
if(result)
mapactivity();
}
else if (items[item].equals("Cancel")) {
dialog.dismiss();
}
}
});
builder.show();
}
public void mapactivity()
{
Intent i=new Intent(CommonChattingAttachmentActivity.this,MapsActivity.class);
startActivity(i);
}
public void startRecording()
{
Intent intent = new Intent(MediaStore.ACTION_VIDEO_CAPTURE);
// create a file to save the video
fileUri = getOutputMediaFileUri(MEDIA_TYPE_VIDEO);
// set the image file name
intent.putExtra(MediaStore.EXTRA_OUTPUT, fileUri);
// set the video image quality to high
intent.putExtra(MediaStore.EXTRA_VIDEO_QUALITY, 1);
// start the Video Capture Intent
startActivityForResult(intent, VIDEO_CAPTURE);
}
/** Create a file Uri for saving an image or video */
private static Uri getOutputMediaFileUri(int type){
return Uri.fromFile(getOutputMediaFile(type));
}
/** Create a File for saving an image or video */
private static File getOutputMediaFile(int type){
// Check that the <a href="#">SDCard</a> is mounted
File mediaStorageDir = new File(Environment.getExternalStoragePublicDirectory(
Environment.DIRECTORY_PICTURES), "MyCameraVideo");
// Create the storage directory(MyCameraVideo) if it does not exist
if (! mediaStorageDir.exists()){
if (! mediaStorageDir.mkdirs()){
// output.setText("Failed to create directory MyCameraVideo.");
// Toast.makeText(this, "Failed to create directory MyCameraVideo.", Toast.LENGTH_LONG).show();
Log.d("MyCameraVideo", "Failed to create directory MyCameraVideo.");
return null;
}
}
java.util.Date date= new java.util.Date();
String timeStamp = new SimpleDateFormat("yyyyMMdd_HHmmss")
.format(date.getTime());
File mediaFile;
if(type == MEDIA_TYPE_VIDEO) {
// For unique video file name appending current timeStamp with file name
mediaFile = new File(mediaStorageDir.getPath() + File.separator +
"VID_"+ timeStamp + ".mp4");
} else {
return null;
}
return mediaFile;
}
public void CaptureVideoFromGallery()
{
Intent intent = new Intent();
intent.setType("video/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, "Select Video"), SELECT_FILES);
}
@Override
public void onRequestPermissionsResult(int requestCode, String[] permissions, int[] grantResults) {
switch (requestCode) {
case Utility.MY_PERMISSIONS_REQUEST_READ_EXTERNAL_STORAGE:
if (grantResults.length > 0 && grantResults[0] == PackageManager.PERMISSION_GRANTED) {
if(userChoosenTask.equals("Take Photo"))
cameraIntent();
else if(userChoosenTask.equals("Choose from Library"))
galleryIntent();
} else {
}
break;
}
}
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (resultCode == RESULT_OK) {
if (requestCode == SELECT_FILE) {
onSelectFromGalleryResult(data);
}
else if (requestCode == REQUEST_CAMERA) {
onCaptureImageResult(data);
}
else if (requestCode == SELECT_FILES) {
onSelectFromGalleryVideoResults(data);
}
else if(requestCode==1)
{
if(resultCode == Activity.RESULT_OK){
String result1=data.getStringExtra("lat");
String result2=data.getStringExtra("lng");
SaveMapData(result1,result2);
}
}
else if (requestCode == VIDEO_CAPTURE) {
Toast.makeText(this, "Video has been saved to:\n" + data.getData(), Toast.LENGTH_LONG).show();
SaveVideoData(String.valueOf(data.getData()));
} else if (resultCode == RESULT_CANCELED) {
Toast.makeText(this, "Video recording cancelled.", Toast.LENGTH_LONG).show();
} else {
Toast.makeText(this, "Failed to record video", Toast.LENGTH_LONG).show();
}
}
}
@SuppressWarnings("deprecation")
public void onSelectFromGalleryResult(Intent data) {
Toast.makeText(CommonChattingAttachmentActivity.this,"My bm"+data,Toast.LENGTH_LONG).show();
SaveImageVideoData(String.valueOf(data.getData()),"gallery");
}
@SuppressWarnings("deprecation")
public void onSelectFromGalleryVideoResults(Intent data) {
Toast.makeText(CommonChattingAttachmentActivity.this,"My bm"+data,Toast.LENGTH_LONG).show();
SaveVideoData(String.valueOf(data));
}
public void onCaptureImageResult(Intent data) {
Bitmap thumbnail = (Bitmap) data.getExtras().get("data");
ByteArrayOutputStream bytes = new ByteArrayOutputStream();
thumbnail.compress(Bitmap.CompressFormat.PNG, 90, bytes);
File destination = new File(Environment.getExternalStorageDirectory(),
System.currentTimeMillis() + ".png");
FileOutputStream fo;
try {
destination.createNewFile();
fo = new FileOutputStream(destination);
fo.write(bytes.toByteArray());
fo.close();
Toast.makeText(CommonChattingAttachmentActivity.this,"No Error",Toast.LENGTH_LONG).show();
} catch (FileNotFoundException e) {
e.printStackTrace();
Toast.makeText(CommonChattingAttachmentActivity.this,"Error Arrived",Toast.LENGTH_LONG).show();
} catch (IOException e) {
e.printStackTrace();
Toast.makeText(CommonChattingAttachmentActivity.this,"Error Arrived again",Toast.LENGTH_LONG).show();
}
SaveImageVideoData(String.valueOf(destination),"camera");
Toast.makeText(CommonChattingAttachmentActivity.this,"its done",Toast.LENGTH_LONG).show();
}
public void SaveImageVideoData(String data,String flag) {
try {
Realm realm = Realm.getDefaultInstance();
realm.beginTransaction();
CommonChat s = realm.createObject(CommonChat.class);
s.setImageUrl(data);
// s.setVideoUrl(data);
s.setFlag(flag);
realm.commitTransaction();
realm.close();
CommonChatRealmHelper helper = new CommonChatRealmHelper(realm);
if (helper.save(s)) {
setAdapter();
}
else
{
Toast.makeText(CommonChattingAttachmentActivity.this, "Invalid Data", Toast.LENGTH_SHORT).show();
}
Log.d("path", data);
Log.d("working realm", "yes....");
Toast.makeText(getApplicationContext(),"Set Image URL"+data,Toast.LENGTH_LONG).show();
}
catch (Exception ex){
Toast.makeText(getApplicationContext(),"Nope its not done",Toast.LENGTH_LONG).show();
}
}
public void SaveVideoData(String data) {
try {
Realm realm = Realm.getDefaultInstance();
realm.beginTransaction();
CommonChat s = realm.createObject(CommonChat.class);
// s.setImageUrl(data);
s.setVideoUrl(data);
//s.setFlag(flag);
realm.commitTransaction();
realm.close();
CommonChatRealmHelper helper = new CommonChatRealmHelper(realm);
if (helper.save(s)) {
setAdapter();
}
else
{
Toast.makeText(CommonChattingAttachmentActivity.this, "Invalid Data", Toast.LENGTH_SHORT).show();
}
Log.d("path", data);
Log.d("working realm", "yes....");
Toast.makeText(getApplicationContext(),"Set Image URL"+data,Toast.LENGTH_LONG).show();
}
catch (Exception ex){
Toast.makeText(getApplicationContext(),"Nope its not done",Toast.LENGTH_LONG).show();
}
}
public void change1()
{
commonchat.setVisibility(View.GONE);
functions.setVisibility(View.VISIBLE);
}
public void change2()
{
commonchat.setVisibility(View.VISIBLE);
functions.setVisibility(View.GONE);
}
@Override
protected void onDestroy() {
super.onDestroy();
realm.removeChangeListener(realmChangeListener);
realm.close();}
}
我的适配器类
public class CCAA extends ArrayAdapter<CommonChat> {
public CCAA(Context context, List<CommonChat> objects){
super(context,0,objects);
this.context = context;
this.mInflater = LayoutInflater.from(context);
contactList = objects;
}
@Override
public CommonChat getItem(int position) {
return contactList.get(position);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
final CCAA.ViewHolder vh;
if (convertView == null) {
View view = mInflater.inflate(R.layout.item_commonchat, parent, false);
vh = CCAA.ViewHolder.create((LinearLayout) view);
view.setTag(vh);
} else {
vh = (CCAA.ViewHolder) convertView.getTag();
}
CommonChat s = getItem(position);
if(s.getVideoUrl()!=null && s.getVideoUrl().length()>0)
{
vh.videoView.setVisibility(View.VISIBLE);
vh.videoView.setVideoPath(s.getVideoUrl());
vh.videoView.setMediaController(new MediaController(context));
vh.videoView.start();
Log.d("start error testing", "test");
Toast.makeText(context, "Got Video URL" + s.getVideoUrl(), Toast.LENGTH_LONG).show();
}
if(vh.txtbeencnt!=null) {
vh.txtbeencnt.setVisibility(View.VISIBLE);
vh.imageView.setVisibility(View.GONE);
vh.videoView.setVisibility(View.GONE);
vh.txtbeencnt.setText(s.getDescription());
}
if(s.getImageUrl() != null && s.getImageUrl().length()>0) {
if (s.getFlag().equalsIgnoreCase("gallery")) {
vh.imageView.setVisibility(View.VISIBLE);
vh.txtbeencnt.setVisibility(View.GONE);
vh.videoView.setVisibility(View.GONE);
Picasso.with(context).load(s.getImageUrl()).placeholder(R.mipmap.ic_launcher).into(vh.imageView);
Toast.makeText(context, "Got Gallery Image URL" + s.getImageUrl(), Toast.LENGTH_LONG).show();
}
else if (s.getFlag().equalsIgnoreCase("camera")) {
vh.imageView.setVisibility(View.VISIBLE);
vh.txtbeencnt.setVisibility(View.GONE);
vh.videoView.setVisibility(View.GONE);
Bitmap bitmap = BitmapFactory.decodeFile(s.getImageUrl());
vh.imageView.setImageBitmap(bitmap);
Toast.makeText(context, "Got Camera Image URL" + s.getImageUrl(), Toast.LENGTH_LONG).show();
}
}
return vh.rootView;
}
private static class ViewHolder {
public final LinearLayout rootView;
public final ImageView imageView;
public final TextView txtbeencnt;
public final VideoView videoView;
public final TextView times;
private ViewHolder(LinearLayout rootView, ImageView imageView, TextView txtbeencnt, VideoView videoView,RelativeTimeTextView times) {
this.rootView = rootView;
this.imageView = imageView;
this.txtbeencnt = txtbeencnt;
this.videoView = videoView;
this.times = times;
}
public static CCAA.ViewHolder create(LinearLayout rootView) {
ImageView imageView = (ImageView) rootView.findViewById(R.id.img);
VideoView videoView = (VideoView) rootView.findViewById(R.id.videoView);
TextView txtbeencnt = (TextView) rootView.findViewById(R.id.textdesc);
RelativeTimeTextView times = (RelativeTimeTextView) rootView.findViewById(R.id.times);
times.setReferenceTime(new Date().getTime());
return new CCAA.ViewHolder(rootView, imageView, txtbeencnt, videoView,times);
}
}
}
我的Logcat
Unexpected activity pause without a matching activity resume. Logging data may be incorrect. Make sure you call activateApp from your Application's onCreate method
10-31 11:10:42.157 29588-29588/com.xitiz.xitizmobile W/IInputConnectionWrapper: showStatusIcon on inactive InputConnection
10-31 11:10:55.247 29588-29588/com.xitiz.xitizmobile D/Testing: CommonChat = [{description:null},{imageUrl:null},{videoUrl:file:///storage/emulated/0/Pictures/MyCameraVideo/VID_20171031_111040.mp4},{MediaPathType:null},{flag:null},{date:null},{Latitude:null},{Longitude:null}]
10-31 11:10:55.257 29588-29588/com.xitiz.xitizmobile D/Testing: CommonChat = [{description:null},{imageUrl:null},{videoUrl:file:///storage/emulated/0/Pictures/MyCameraVideo/VID_20171031_111040.mp4},{MediaPathType:null},{flag:null},{date:null},{Latitude:null},{Longitude:null}]
10-31 11:10:55.257 29588-29588/com.xitiz.xitizmobile D/Testing: CommonChat = [{description:null},{imageUrl:null},{videoUrl:file:///storage/emulated/0/Pictures/MyCameraVideo/VID_20171031_111040.mp4},{MediaPathType:null},{flag:null},{date:null},{Latitude:null},{Longitude:null}]
10-31 11:10:55.257 29588-29588/com.xitiz.xitizmobile D/path: file:///storage/emulated/0/Pictures/MyCameraVideo/VID_20171031_111040.mp4
10-31 11:10:55.257 29588-29588/com.xitiz.xitizmobile D/working realm: yes....
10-31 11:10:55.367 29588-29588/com.xitiz.xitizmobile D/start error testing: test
10-31 11:11:03.157 29588-29588/com.xitiz.xitizmobile W/IInputConnectionWrapper: showStatusIcon on inactive InputConnection
10-31 11:11:05.147 29588-29588/com.xitiz.xitizmobile D/Testing: CommonChat = [{description:null},{imageUrl:null},{videoUrl:file:///storage/emulated/0/Pictures/MyCameraVideo/VID_20171031_111040.mp4},{MediaPathType:null},{flag:null},{date:null},{Latitude:null},{Longitude:null}]
10-31 11:11:05.147 29588-29588/com.xitiz.xitizmobile D/Testing: CommonChat = [{description:null},{imageUrl:null},{videoUrl:Intent { dat=content://com.android.providers.media.documents/document/video:146337 flg=0x1 }},{MediaPathType:null},{flag:null},{date:null},{Latitude:null},{Longitude:null}]
10-31 11:11:05.157 29588-29588/com.xitiz.xitizmobile D/Testing: CommonChat = [{description:null},{imageUrl:null},{videoUrl:file:///storage/emulated/0/Pictures/MyCameraVideo/VID_20171031_111040.mp4},{MediaPathType:null},{flag:null},{date:null},{Latitude:null},{Longitude:null}]
10-31 11:11:05.157 29588-29588/com.xitiz.xitizmobile D/Testing: CommonChat = [{description:null},{imageUrl:null},{videoUrl:Intent { dat=content://com.android.providers.media.documents/document/video:146337 flg=0x1 }},{MediaPathType:null},{flag:null},{date:null},{Latitude:null},{Longitude:null}]
10-31 11:11:05.157 29588-29588/com.xitiz.xitizmobile D/Testing: CommonChat = [{description:null},{imageUrl:null},{videoUrl:file:///storage/emulated/0/Pictures/MyCameraVideo/VID_20171031_111040.mp4},{MediaPathType:null},{flag:null},{date:null},{Latitude:null},{Longitude:null}]
10-31 11:11:05.157 29588-29588/com.xitiz.xitizmobile D/Testing: CommonChat = [{description:null},{imageUrl:null},{videoUrl:Intent { dat=content://com.android.providers.media.documents/document/video:146337 flg=0x1 }},{MediaPathType:null},{flag:null},{date:null},{Latitude:null},{Longitude:null}]
10-31 11:11:05.167 29588-29588/com.xitiz.xitizmobile D/Testing: CommonChat = [{description:null},{imageUrl:null},{videoUrl:file:///storage/emulated/0/Pictures/MyCameraVideo/VID_20171031_111040.mp4},{MediaPathType:null},{flag:null},{date:null},{Latitude:null},{Longitude:null}]
10-31 11:11:05.167 29588-29588/com.xitiz.xitizmobile D/Testing: CommonChat = [{description:null},{imageUrl:null},{videoUrl:Intent { dat=content://com.android.providers.media.documents/document/video:146337 flg=0x1 }},{MediaPathType:null},{flag:null},{date:null},{Latitude:null},{Longitude:null}]
10-31 11:11:05.167 29588-29588/com.xitiz.xitizmobile D/Testing: CommonChat = [{description:null},{imageUrl:null},{videoUrl:file:///storage/emulated/0/Pictures/MyCameraVideo/VID_20171031_111040.mp4},{MediaPathType:null},{flag:null},{date:null},{Latitude:null},{Longitude:null}]
10-31 11:11:05.167 29588-29588/com.xitiz.xitizmobile D/Testing: CommonChat = [{description:null},{imageUrl:null},{videoUrl:Intent { dat=content://com.android.providers.media.documents/document/video:146337 flg=0x1 }},{MediaPathType:null},{flag:null},{date:null},{Latitude:null},{Longitude:null}]
10-31 11:11:05.167 29588-29588/com.xitiz.xitizmobile D/path: Intent { dat=content://com.android.providers.media.documents/document/video:146337 flg=0x1 }
10-31 11:11:05.167 29588-29588/com.xitiz.xitizmobile D/working realm: yes....
10-31 11:11:05.217 29588-29588/com.xitiz.xitizmobile D/start error testing: test
10-31 11:11:05.237 29588-29588/com.xitiz.xitizmobile D/start error testing: test
任何人都可以告诉我我错在哪里，因为我从摄影机和画廊获取视频路径，但问题是视频未在listview中显示，因为它返回空白。请看看我的编辑和完整的Logcat可以更好地了解错误。
答案 0 :(得分：1)
我刚刚发过帖子{videoUrl：file：///storage/emulated/0/1509080683539.mp4}的路径不正确
if(s.getVideoUrl()!=null && s.getVideoUrl().length()>0){
vh.videoView.setVisibility(View.VISIBLE);
File videoFile = new File(s.getVideoUrl);
vh.videoView.setVideoPath(videoFile.getAbsolutePath());
vh.videoView.start();
vh.videoView.setMediaController(newMediaController(context));
Toast.makeText(context, "Got Video URL" + s.getVideoUrl(), Toast.LENGTH_LONG).show();
}
PostText ：在阅读文件时，不要忘记添加权限android.permission.READ_EXTERNAL_STORAGE。