getting an error “java.lang.IllegalStateException: Can print only from an activity”?
Question
I am getting an error " java.lang.IllegalStateException : Can print only from an activity" while using an android 4.4 printing API.
is it work on all android above 4.4?
my code
public class MainActivity extends Activity {
Context cotext;
WebView mWebView;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
cotext = getApplicationContext();
}
public void printData(View view){
doWebViewPrint();
}
private void doWebViewPrint() {
// Create a WebView object specifically for printing
WebView webView = new WebView(cotext);
webView.setWebViewClient(new WebViewClient() {
public boolean shouldOverrideUrlLoading(WebView view, String url) {
return false;
}
@Override
public void onPageFinished(WebView view, String url) {
Log.i("TAG", "page finished loading " + url);
createWebPrintJob(view);
mWebView = null;
}
});
// Generate an HTML document on the fly:
String htmlDocument = "<html><body><h1>Test Content</h1><p>Testing, " +
"testing, testing...</p></body></html>";
webView.loadDataWithBaseURL(null, htmlDocument, "text/HTML", "UTF-8", null);
// Keep a reference to WebView object until you pass the PrintDocumentAdapter
// to the PrintManager
mWebView = webView;
}
private void createWebPrintJob(WebView webView) {
// Get a PrintManager instance
PrintManager printManager = (PrintManager) cotext
.getSystemService(Context.PRINT_SERVICE);
// Get a print adapter instance
PrintDocumentAdapter printAdapter = webView.createPrintDocumentAdapter();
// Create a print job with name and adapter instance
String jobName = getString(R.string.app_name) + " Document";
printManager.print(jobName, printAdapter,
new PrintAttributes.Builder().build());
// Save the job object for later status checking
//mPrintJobs.add(printJob);
}
}
please help me.
is there any example of android wifi printing?
3 answers
solution1
12 2016-11-04 04:55:12
I know this is late answer.
You have to use YourCurrentActivity.this instead of getApplicationContext()
Because getApplicationContext() refers to an whole application context while YourCurrentActivity.this refers only current activity context .
solution2
9 2019-11-16 06:53:51
My application is using PDF printing using PrintManager . I got this issue after I implemented Multi-language support.
Android create a new context via createConfigurationContext() . This invalidates the reference being used by the PrintManager instance, causing the above IllegalStateException .
Solution
My solution is to store a reference of the original context passed by attachBaseContext() a member of my activity. Then retrieve PrintManager instance by calling getSystemService() on the original context reference instead of the inactive context reference.
private Context originalContext;
@Override
protected void attachBaseContext(Context newBase) {
this.originalContext = newBase;
super.attachBaseContext(LocaleHelper.onAttach(newBase,appLocale));
}
// Starting printing (PDF generation):
PrintManager printManager = (PrintManager) originalContext.getSystemService(Context.PRINT_SERVICE);
solution3
1 2016-06-14 18:41:50
If you're printing HTML content, this Android training is faster and easier.
Now for the exception, I think you are getting this exception because of this line:
PrintManager printManager = (PrintManager) cotext
.getSystemService(Context.PRINT_SERVICE);
The context you're using is an application context although you're in an activity and can/should just use the activity as a context. I'm not sure why you would need a separate cotext at all in this code.
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