我正在制作一个应用程序，我想在 facebook 上发布视频。但是在提供视频参考时，我得到空指针异常。请告诉我如何解决这个问题。
这是代码：
public class Example extends Activity {
// Your Facebook Application ID must be set before running this example
// See http://www.facebook.com/developers/createapp.php
public static final String APP_ID = "175729095772478";
private LoginButton mLoginButton;
private TextView mText;
private Button mRequestButton;
private Button mPostButton;
private Button mDeleteButton;
private Button mUploadButton;
private Facebook mFacebook;
private AsyncFacebookRunner mAsyncRunner;
/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (APP_ID == null) {
Util.showAlert(this, "Warning", "Facebook Applicaton ID must be " +
"specified before running this example: see Example.java");
}
setContentView(R.layout.main);
mLoginButton = (LoginButton) findViewById(R.id.login);
mText = (TextView) Example.this.findViewById(R.id.txt);
mRequestButton = (Button) findViewById(R.id.requestButton);
mPostButton = (Button) findViewById(R.id.postButton);
mDeleteButton = (Button) findViewById(R.id.deletePostButton);
mUploadButton = (Button) findViewById(R.id.uploadButton);
mFacebook = new Facebook(APP_ID);
mAsyncRunner = new AsyncFacebookRunner(mFacebook);
SessionStore.restore(mFacebook, this);
SessionEvents.addAuthListener(new SampleAuthListener());
SessionEvents.addLogoutListener(new SampleLogoutListener());
mLoginButton.init(this, mFacebook);
mRequestButton.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
mAsyncRunner.request("me", new SampleRequestListener());
}
});
mRequestButton.setVisibility(mFacebook.isSessionValid() ?
View.VISIBLE :
View.INVISIBLE);
mUploadButton.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
byte[] data = null;
AssetFileDescriptor fileDesc = getResources().openRawResourceFd(
R.raw.movie);
String dataPath = fileDesc.toString();
String dataMsg = "Your video description here.";
String dataName = "movie.mp4";
Bundle param;
AsyncFacebookRunner mAsyncRunner = new AsyncFacebookRunner(mFacebook);
InputStream is ;
try
{
is = new FileInputStream(dataPath);
if(is != null)
data = readBytes(is);
param = new Bundle();
param.putString("message", dataMsg);
param.putString("filename", dataName);
param.putByteArray("video", data);
mAsyncRunner.request(null, param, "POST", new SampleUploadListener(), null);
}
catch (FileNotFoundException e) {
e.printStackTrace();
}
catch (IOException e) {
e.printStackTrace();
}
}
});
mUploadButton.setVisibility(mFacebook.isSessionValid() ?
View.VISIBLE :
View.INVISIBLE);
mPostButton.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
mFacebook.dialog(Example.this, "feed",
new SampleDialogListener());
}
});
mPostButton.setVisibility(mFacebook.isSessionValid() ?
View.VISIBLE :
View.INVISIBLE);
mPostButton.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
mFacebook.dialog(Example.this, "feed",
new SampleDialogListener());
}
});
mPostButton.setVisibility(mFacebook.isSessionValid() ?
View.VISIBLE :
View.INVISIBLE);
}
public byte[] readBytes(InputStream inputStream) throws IOException {
// This dynamically extends to take the bytes you read.
ByteArrayOutputStream byteBuffer = new ByteArrayOutputStream();
// This is storage overwritten on each iteration with bytes.
int bufferSize = 1024;
byte[] buffer = new byte[bufferSize];
// We need to know how may bytes were read to write them to the byteBuffer.
int len = 0;
while ((len = inputStream.read(buffer)) != -1) {
byteBuffer.write(buffer, 0, len);
}
// And then we can return your byte array.
return byteBuffer.toByteArray();
}
@Override
protected void onActivityResult(int requestCode, int resultCode,
Intent data) {
mFacebook.authorizeCallback(requestCode, resultCode, data);
}
public class SampleAuthListener implements AuthListener {
public void onAuthSucceed() {
mText.setText("You have logged in! ");
mRequestButton.setVisibility(View.VISIBLE);
mUploadButton.setVisibility(View.VISIBLE);
mPostButton.setVisibility(View.VISIBLE);
}
public void onAuthFail(String error) {
mText.setText("Login Failed: " + error);
}
}
public class SampleLogoutListener implements LogoutListener {
public void onLogoutBegin() {
mText.setText("Logging out...");
}
public void onLogoutFinish() {
mText.setText("You have logged out! ");
mRequestButton.setVisibility(View.INVISIBLE);
mUploadButton.setVisibility(View.INVISIBLE);
mPostButton.setVisibility(View.INVISIBLE);
}
}
public class SampleRequestListener extends BaseRequestListener {
public void onComplete(final String response, final Object state) {
try {
// process the response here: executed in background thread
Log.d("Facebook-Example", "Response: " + response.toString());
JSONObject json = Util.parseJson(response);
final String name = json.getString("name");
// then post the processed result back to the UI thread
// if we do not do this, an runtime exception will be generated
// e.g. "CalledFromWrongThreadException: Only the original
// thread that created a view hierarchy can touch its views."
Example.this.runOnUiThread(new Runnable() {
public void run() {
mText.setText("Hello there, " + name + "!");
}
});
} catch (JSONException e) {
Log.w("Facebook-Example", "JSON Error in response");
} catch (FacebookError e) {
Log.w("Facebook-Example", "Facebook Error: " + e.getMessage());
}
}
}
public class SampleUploadListener extends BaseRequestListener {
public void onComplete(final String response, final Object state) {
try {
// process the response here: (executed in background thread)
Log.d("Facebook-Example", "Response: " + response.toString());
JSONObject json = Util.parseJson(response);
final String src = json.getString("src");
// then post the processed result back to the UI thread
// if we do not do this, an runtime exception will be generated
// e.g. "CalledFromWrongThreadException: Only the original
// thread that created a view hierarchy can touch its views."
Example.this.runOnUiThread(new Runnable() {
public void run() {
mText.setText("Hello there, photo has been uploaded at \n" + src);
}
});
} catch (JSONException e) {
Log.w("Facebook-Example", "JSON Error in response");
} catch (FacebookError e) {
Log.w("Facebook-Example", "Facebook Error: " + e.getMessage());
}
}
}
public class WallPostRequestListener extends BaseRequestListener {
public void onComplete(final String response, final Object state) {
Log.d("Facebook-Example", "Got response: " + response);
String message = "<empty>";
try {
JSONObject json = Util.parseJson(response);
message = json.getString("message");
} catch (JSONException e) {
Log.w("Facebook-Example", "JSON Error in response");
} catch (FacebookError e) {
Log.w("Facebook-Example", "Facebook Error: " + e.getMessage());
}
final String text = "Your Wall Post: " + message;
Example.this.runOnUiThread(new Runnable() {
public void run() {
mText.setText(text);
}
});
}
}
public class WallPostDeleteListener extends BaseRequestListener {
public void onComplete(final String response, final Object state) {
if (response.equals("true")) {
Log.d("Facebook-Example", "Successfully deleted wall post");
Example.this.runOnUiThread(new Runnable() {
public void run() {
mDeleteButton.setVisibility(View.INVISIBLE);
mText.setText("Deleted Wall Post");
}
});
} else {
Log.d("Facebook-Example", "Could not delete wall post");
}
}
}
public class SampleDialogListener extends BaseDialogListener {
public void onComplete(Bundle values) {
final String postId = values.getString("post_id");
if (postId != null) {
Log.d("Facebook-Example", "Dialog Success! post_id=" + postId);
mAsyncRunner.request(postId, new WallPostRequestListener());
mDeleteButton.setOnClickListener(new OnClickListener() {
public void onClick(View v) {
mAsyncRunner.request(postId, new Bundle(), "DELETE",
new WallPostDeleteListener(), null);
}
});
mDeleteButton.setVisibility(View.VISIBLE);
} else {
Log.d("Facebook-Example", "No wall post made");
}
}
}
}
这是一个例外：
08-25 22:22:12.521: W/System.err(385): java.io.FileNotFoundException: /{AssetFileDescriptor: {ParcelFileDescriptor: java.io.FileDescriptor@44ea68c8} start=12468 len=466888}
08-25 22:22:12.630: W/System.err(385): at org.apache.harmony.luni.platform.OSFileSystem.open(OSFileSystem.java:244)
08-25 22:22:12.662: W/System.err(385): at java.io.FileInputStream.<init>(FileInputStream.java:77)
08-25 22:22:12.671: W/System.err(385): at java.io.FileInputStream.<init>(FileInputStream.java:130)
08-25 22:22:12.691: W/System.err(385): at com.facebook.android.Example$2.onClick(Example.java:107)
08-25 22:22:12.691: W/System.err(385): at android.view.View.performClick(View.java:2364)
08-25 22:22:12.702: W/System.err(385): at android.view.View.onTouchEvent(View.java:4179)
08-25 22:22:12.710: W/System.err(385): at android.widget.TextView.onTouchEvent(TextView.java:6541)
08-25 22:22:12.730: W/System.err(385): at android.view.View.dispatchTouchEvent(View.java:3709)
08-25 22:22:12.741: W/System.err(385): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884)
08-25 22:22:12.750: W/System.err(385): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884)
08-25 22:22:12.750: W/System.err(385): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884)
08-25 22:22:12.762: W/System.err(385): at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:884)
08-25 22:22:12.780: W/System.err(385): at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:1659)
08-25 22:22:12.780: W/System.err(385): at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1107)
08-25 22:22:12.791: W/System.err(385): at android.app.Activity.dispatchTouchEvent(Activity.java:2061)
08-25 22:22:12.801: W/System.err(385): at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1643)
08-25 22:22:12.810: W/System.err(385): at android.view.ViewRoot.handleMessage(ViewRoot.java:1691)
08-25 22:22:12.834: W/System.err(385): at android.os.Handler.dispatchMessage(Handler.java:99)
08-25 22:22:12.841: W/System.err(385): at android.os.Looper.loop(Looper.java:123)
08-25 22:22:12.852: W/System.err(385): at android.app.ActivityThread.main(ActivityThread.java:4363)
08-25 22:22:12.860: W/System.err(385): at java.lang.reflect.Method.invokeNative(Native Method)
08-25 22:22:12.871: W/System.err(385): at java.lang.reflect.Method.invoke(Method.java:521)
08-25 22:22:12.881: W/System.err(385): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
08-25 22:22:12.890: W/System.err(385): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
08-25 22:22:12.900: W/System.err(385): at dalvik.system.NativeStart.main(Native Method)
我在这条线上遇到了异常。
is = new FileInputStream(dataPath);