我正在尝试开发一个可以将文件从手机上传到我的笔记本电脑的Android应用程序。我有两个活动：
我正在尝试浏览Filechooser活动中的文件，并通过putExtra和getExtra传递文件目录，但无法上传。但是，如果我对文件目录进行硬编码，它将成功上传文件。
这是代码。由于我是初学者，请详细说明你的答案。
简单客户活动
public class SlimpleTextClientActivity extends Activity {
public Socket client;
public PrintWriter printwriter;
public EditText textField;
public Button button1,button2;
public String messsage;
public String file_path;
public int count=1;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_slimple_text_client);
textField = (EditText) findViewById(R.id.editText1); // reference to the text field
button1 = (Button) findViewById(R.id.button1); // reference to the filechoosing button
button2 = (Button) findViewById(R.id.button2);//reference to send button
// Button press event listener
button1.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
Intent i = new Intent(SlimpleTextClientActivity.this, FileChooser.class);
startActivity(i);
Intent intent=getIntent();
String directory1;
Bundle b = getIntent().getExtras();
try {
directory1 = b.getString("directory");
file_path = directory1;
} catch (Exception e) {
textField.setText(e.getMessage());
directory1="returned nothon";
}
if (file_path == null) {
file_path = "no file choosen";
}
textField.setText(directory1);
}
}
);
button2.setOnClickListener(new View.OnClickListener() {
public void onClick(View v) {
SendMessage sendMessageTask = new SendMessage();
sendMessageTask.execute();
}
}
);
}
private class SendMessage extends AsyncTask<Void, Void, Void> {
private FileInputStream fileInputStream;
private BufferedInputStream bufferedInputStream;
private OutputStream outputStream;
private Button button;
@Override
protected Void doInBackground(Void... params) {
Socket socket;
try
{int count=0;
socket = new Socket("192.168.137.1", 4444);
if(!socket.isConnected())
textField.setText("Socket Connection Not established");
else
System.out.println("Socket Connection established : "+socket.getInetAddress()); File myfile = new File(file_path);
//local file path.
if(!myfile.exists())
System.out.println("File Not Existing.");
else
System.out.println("File Existing.");
byte[] byteArray = new byte[100];
FileInputStream fis = new FileInputStream(myfile);
BufferedInputStream bis = new BufferedInputStream(fis);
OutputStream os = socket.getOutputStream();
int trxBytes =0;
while((trxBytes = bis.read(byteArray, 0, byteArray.length)) !=-1)
{
os.write(byteArray, 0, byteArray.length);
System.out.println("Transfering bytes : "+trxBytes );
}
os.flush();
bis.close();
socket.close();
System.out.println("File Transfered...");
}
catch(Exception e)
{
System.out.println("Client Exception : "+e.getMessage());
}
return null;
}
}
@Override
public boolean onCreateOptionsMenu (Menu menu){
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_slimple_text_client, menu);
return true;
}
public boolean onKeyDown(int keyCode, KeyEvent event) {
// Check if the key event was the Back button and if there's history
if ((keyCode == KeyEvent.KEYCODE_BACK)) {
AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(
this);
// set title
alertDialogBuilder.setTitle("Dude are you serious???");
// set dialog message
alertDialogBuilder
.setMessage("Do you want to quit??")
.setCancelable(false)
.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
SlimpleTextClientActivity.this.finish();
}
})
.setNegativeButton("No", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
// if this button is clicked, just close
// the dialog box and do nothing
dialog.cancel();
}
});
// create alert dialog
AlertDialog alertDialog = alertDialogBuilder.create();
// show it
alertDialog.show();
//super.onBackPressed();
// return true;
}
return false;
}}
2.FileChooser活动
public class FileChooser extends ListActivity {
//Intent intentchooser=getIntent();
public String directory;
private List<String> item = null;
private List<String> path = null;
private String root;
private TextView myPath;
public EditText textField;
final Context context = this;
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.file);
myPath = (TextView)findViewById(R.id.path);
// textField=(EditText)findViewById(R.id.small);
root = Environment.getExternalStorageDirectory().getPath();
getDir(root);
}
public File f;
private void getDir(String dirPath)
{
myPath.setText("Location: " + dirPath);
item = new ArrayList<String>();
path = new ArrayList<String>();
f = new File(dirPath);
File[] files = f.listFiles();
if(!dirPath.equals(root))
{
item.add(root);
path.add(root);
item.add("../");
path.add(f.getParent());
}
for(int i=0; i < files.length; i++)
{
File file = files[i];
if(!file.isHidden() && file.canRead()){
path.add(file.getPath());
if(file.isDirectory()){
item.add(file.getName() + "/");
}else{
item.add(file.getName());
}
}
}
ArrayAdapter<String> fileList =
new ArrayAdapter<String>(this, R.layout.row, item);
setListAdapter(fileList);
}
@Override
protected void onListItemClick(ListView l, View v, int position, long id) {
// TODO Auto-generated method stub
File file = new File(path.get(position));
AlertDialog.Builder alertDialogBuilder = new AlertDialog.Builder(
context);
if (file.isDirectory())
{
if(file.canRead()){
getDir(path.get(position));
}else{
new AlertDialog.Builder(this)
.setIcon(R.drawable.ic_launcher)
.setTitle("[" + file.getName() + "] folder can't be read!")
.setPositiveButton("OK", null).show();
// this.finish();
}
}else {
final File filetemp=file;
AlertDialog.Builder alertDialogBuilder1 = new AlertDialog.Builder(
context);
// set title
alertDialogBuilder.setTitle("Ready to upload???");
// set dialog message
alertDialogBuilder1
.setMessage("Do you want upload??")
.setCancelable(false)
.setPositiveButton("OK",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int id) {
// if this button is clicked, close
// current activity
FileChooser.this.finish();
Intent in=new Intent(FileChooser.this,SlimpleTextClientActivity.class);
in.putExtra("directory",filetemp.getAbsolutePath());
System.out.println("\n\n\n\n\n\n"+filetemp.getAbsolutePath()+"\n\n\n\n\n");
// textField.setText(filetemp.getAbsolutePath());
startActivity(in);
}
})
.setNegativeButton("No",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int id) {
// if this button is clicked, just close
// the dialog box and do nothing
dialog.cancel();
}
});
// create alert dialog
AlertDialog alertDialog = alertDialogBuilder1.create();
// show it
alertDialog.show();
textField.setText("file.getAbsolutePath()");
Intent in=new Intent(FileChooser.this,SlimpleTextClientActivity.class);
startActivity(in);
finish();
}
}
public boolean onKeyDown(int keyCode, KeyEvent event)
{
// Check if the key event was the Back button and if there's history
if ((keyCode == KeyEvent.KEYCODE_BACK))
{
AlertDialog.Builder alertDialogBuilder = ne`enter code here`w AlertDialog.Builder(
context);
// set title
alertDialogBuilder.setTitle("Dude are you serious???");
// set dialog message
alertDialogBuilder
.setMessage("Do you want to cancel file uploading??")
.setCancelable(false)
.setPositiveButton("Yes",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int id) {
// if this button is clicked, close
// current activity
FileChooser.this.finish();
Intent in=new Intent(FileChooser.this,SlimpleTextClientActivity.class);
in.putExtra("directory","yo baby ");
startActivity(in);
}
})
.setNegativeButton("No",new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog,int id) {
// if this button is clicked, just close
// the dialog box and do nothing
dialog.cancel();
}
});
// create alert dialog
AlertDialog alertDialog = alertDialogBuilder.create();
// show it
alertDialog.show();
//super.onBackPressed();
// return true;
}
return false;
}
}
如果我不处理异常
，这就是应用程序崩溃的地方 try {
directory1 = b.getString("directory");
file_path = directory1;
} catch (Exception e) {
textField.setText(e.getMessage());
directory1="returned nothin";
}
这是我的xml文件。
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="shiva.com.filesenderlakj;"
android:versionCode="1"
android:versionName="1.0" >
<uses-sdk
android:minSdkVersion="11"
android:targetSdkVersion="19" />
<uses-permission android:name="android.permission.INTERNET" >
</uses-permission>
<uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" >
</uses-permission>
<uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE" >
</uses-permission>
<application
android:allowBackup="true"
android:icon="@drawable/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name="shiva.com.filesenderlakj.SlimpleTextClientActivity"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<intent-filter>
<action android:name="android.intent.action.SEND" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
<activity
android:name="shiva.com.filesenderlakj.FileChooser"
android:label="@string/app_name" >
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
<intent-filter>
<action android:name="android.intent.action.SEND" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
答案 0 :(得分：0)
如果您的代码在此处引发异常
try {
directory1 = b.getString("directory");
file_path = directory1;
} catch (Exception e) {
textField.setText(e.getMessage());
directory1="returned nothon";
}
这意味着您的意图中没有"directory"额外费用。
当你开始SimpleClientActivity时，你需要确保使用"directory"额外的意图。
免责声明：我输入此代码时没有编译或进行任何检查。这仅仅是为了指导您如何将“正确”的处理方式集成到您的应用程序中。
要制作BroadcastReceiver，您可以执行以下操作：
BroadcastReceiver br = new BroadcastReceiver() {
@Override
onReceive(Context context, Intent intent) {
Bundle b = intent.getExtras();
if (b.hasExtra(DIRECTORY_EXTRA)) {
textField.setText(b.getString(DIRECTORY_EXTRA));
}
}
}
这样做是因为当您的BroadcastReceiver收到一个意图时，onReceived（）将使用接收器运行的上下文及其收到的意图进行调用。
要将BroadcastReceiver设置为接收意图，您需要使用意图过滤器为特定类型的意图注册它：
IntentFilter myIntentFilter = new IntentFilter("my.app.package.myintent");
然后，您可以将BrodacastReceiver与IntentFilter配对，以告知Android操作系统在发送意向广播时向您转发意图。
@Override
public void onCreate(Bundle savedInstanceState) {
// <make the BroadcastReceiver>
// <make the intent filter>
registerReceiver (br, myIntentFilter);
}
现在，您可以使用sendBroadcast。而不是使用startActivity进行通信。
Intent myIntent = new Intent("my.app.package.myintent");
myIntent.putExtra(DIRECTORY_EXTRA, directoryString);
sendBroadcast(myIntent);