[SOLVED] Qt on Android : Open an external file

nologinma

I'd like to open an external file from my app (for Android) but I have a big problem.

The code is the following:

@
QString myfile;
myfile = "/data/data/com.sample.org/sample.kml";
myfile = QDir::toNativeSeparators(myfile);
myfile = "file:///" + myfile;
QDesktopServices::openUrl(QUrl(myfile));
@

If I run the same code in the desktop I haven't problem and the file is opened (in particolar mode Window ask me what application I have to associate to open the file; Google Earth in this case).

The same example worked fine with Symbian, but with Android I have no response.

Please can you help me ? There is a alternative way ?

jiangcaiyang

I guess you add an extra slash '/', try delete one.
Another proper way to test whether this url is correct is using QFileDialog to let user select one, then print the file path selected by the user.

nologinma

I did several tests:

@

QString myfile;
myfile = getXMLFileName();
myfile = QDir::toNativeSeparators(myfile);
myfile = "file:////" + myfile;
QDesktopServices::openUrl(QUrl(myfile));
@

after also the following:

@
QString myfile;
myfile = getXMLFileName();
myfile = QDir::toNativeSeparators(myfile);
myfile = "file://" + myfile;
QDesktopServices::openUrl(QUrl(myfile));
@

and the following:

@
QString myfile;
myfile = getXMLFileName();
myfile = QDir::toNativeSeparators(myfile);
QDesktopServices::openUrl(QUrl(myfile));
@

but none works.

The Application output is the following:

@D/Instrumentation(13081): checkStartActivityResult :Intent { act=android.intent.action.VIEW dat=/data/data/org.qtproject.gsp/files/gps.kml }
D/Instrumentation(13081): checkStartActivityResult inent is instance of inent:
W/System.err(13081): android.content.ActivityNotFoundException: No Activity found to handle Intent { act=android.intent.action.VIEW dat=/data/data/org.qtproject.gsp/files/gps.kml }
W/System.err(13081): at android.app.Instrumentation.checkStartActivityResult(Instrumentation.java:1580)
W/System.err(13081): at android.app.Instrumentation.execStartActivity(Instrumentation.java:1431)
W/System.err(13081): at android.app.Activity.startActivityForResult(Activity.java:3428)
W/System.err(13081): at android.app.Activity.startActivityForResult(Activity.java:3389)
W/System.err(13081): at android.app.Activity.startActivity(Activity.java:3599)
W/System.err(13081): at android.app.Activity.startActivity(Activity.java:3567)
W/System.err(13081): at org.qtproject.qt5.android.QtNative.openURL(QtNative.java:116)
W/System.err(13081): at dalvik.system.NativeStart.run(Native Method)
W/IInputConnectionWrapper(13081): getSelectedText on inactive InputConnection
W/IInputConnectionWrapper(13081): setComposingText on inactive InputConnection
W/IInputConnectionWrapper(13081): getExtractedText on inactive InputConnection@

I think it is a permissions issue.

to resolve the problem above I have add the following block inside the AndroidMnifest:

@<intent-filter>
<action android:name="android.intent.action.VIEW"/>
<category android:name="android.intent.category.DEFAULT"/>
<data android:scheme="file">
</intent-filter>@

and now I haven't the error above but the file is not opened......(from google earth or another program).

The message inside the Application output now is the following:

@D/AbsListView( 9087): Get MotionRecognitionManager@

but the application associate don't start...

Where am I doing wrong?

cmazieri

Perhaps, there is no application assigned to open this kind of file.

QDesktopServices::openUrl() should use local system resources to open the file.

Try to open more common files like: mp3 , html, pdf or text files.

nologinma

I have change the directory where I create the kml file:

from

/data/data/org.qtproject.gsp/files/gps.kml

to

/storage/sdcard0/Documents/gps.kml

and I have removed the code inside the AndroidManifest following:

@<intent-filter>
<action android:name="android.intent.action.VIEW"/>
<category android:name="android.intent.category.DEFAULT"/>
<data android:scheme="file">
</intent-filter>@

and now the Google Earth start.

bq. Probably the initial directory was not accessible.

1) Google Earth start but does not load the KML file even if it is well-formed

2) An App in which directory should create a file? Is there a directory name in which to write the official files?

nologinma

bq. 2) An App in which directory should create a file? Is there a directory name in which to write the official files?

For the scond question, the answer is the following: (what I used)

@QString path = QStandardPaths::writableLocation(QStandardPaths::GenericDataLocation);

path.append("/gps");@

bq. 1) Google Earth start but does not load the KML file even if it is well-formed

for the moment I have no solution.

My app open the Google Earth but not view the path inside the kml file.

If I open the file without app from file browser the kml file is opend well.

very strange

nologinma

I have found an altenative solution.

I can call a java class file from qt c++ and open the file using JNI method.

The java class is the following:

@//
// Next72Utility.java
//
package org.qtproject.example.Chronometer;

import android.app.Activity;
import java.lang.Runnable;
import android.content.Intent;
import java.io.File;
import android.net.Uri;

public class Next72Utility extends org.qtproject.qt5.android.bindings.QtActivity
{

public static Next72Utility m_istance;

public Next72Utility()
{
m_istance = this;
}

public static void openUrl(final String m_url, final String m_application_type)
{
m_istance.runOnUiThread(new Runnable() {
public void run() {

         Intent intent = new Intent();
         intent.setAction(android.content.Intent.ACTION_VIEW);
         File file = new File&#40;m_url&#41;;
         intent.setDataAndType(Uri.fromFile(file&#41;, m_application_type&#41;;
         m_istance.startActivity(intent);
     }
   });

}

}@

and the call from c++ is the following:

@QAndroidJniObject m_url = QAndroidJniObject::fromString("storage/sdcard0/gps/gps.kml");

QAndroidJniObject m_application_type = QAndroidJniObject::fromString("application/vnd.google-earth.kml+xml");

QAndroidJniObject::callStaticMethod<void>("org/qtproject/example/Chronometer/Next72Utility", "openUrl", "(Ljava/lang/String;Ljava/lang/String;)V",m_url.object<jstring>(),m_application_type.object<jstring>());@

EdOfTheMountain

I agree that it was a permissions problem.

I finally succeeded in opening a KML file in Google Earth without resorting to JNI.
The KML file must be located in external storage where Google Earth can access it.

@
// Saving KML file in QStandardPaths::DownloadLocation will work
QString destinationFolder = QStandardPaths::writableLocation(QStandardPaths::DownloadLocation);

// The KML file must be opened from a folder accessible to Google Earth app
// This will not work: /data/data/com.myccompany.myapp/
// This works........: /storage/emulated/0/Download/JOB-0001.kml
// /storage/sdcard0/Download/JOB-0001.kml
//
// Android: QStandardPaths::DownloadLocation

QUrl urlToLocalKmlFile =
        QUrl::fromLocalFile&#40;kmlFileNamePath&#41;;
bool success = QDesktopServices::openUrl(urlToLocalKmlFile&#41;;
if( success&#41;
{
    return;
}

qCritical("openUrl failed?");

@

EdOfTheMountain

This post is deleted!