How to start AlertDialog regardless the context? Android

Question

I`m doing little diagnostics project for fiscal printer in Android. So when printing , a problem may occurs (missing paper ect.). In that case i want to start an AlertDialog notifying that there is a problem and asking the user does he wants to continue printing.

I want to make an AlertDialog that shows infront regardless the activity that is currently being brought to front.

I have tried the usual way of starting AlertDialog using GetAplicationContext() method but it crashes badly.

Here is the stacktrace:

05-11 17:36:56.162: W/dalvikvm(5458): threadid=3: thread exiting with uncaught exception (group=0x4001e390)
05-11 17:36:56.162: E/AndroidRuntime(5458): Uncaught handler: thread main exiting due to uncaught exception
05-11 17:36:56.182: E/AndroidRuntime(5458): java.lang.NullPointerException
05-11 17:36:56.182: E/AndroidRuntime(5458):     at android.content.ContextWrapper.getApplicationContext(ContextWrapper.java:100)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at bg.barcodes.mobile.routes.java.BaseActivity.onCreateDialog(BaseActivity.java:21)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at bg.barcodes.mobile.routes.java.DatecsPrinter.Send(DatecsPrinter.java:319)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at bg.barcodes.mobile.routes.java.DatecsPrinter.sendText(DatecsPrinter.java:381)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at bg.barcodes.mobile.routes.java.StatusDatecsPrinter.doCommand(StatusDatecsPrinter.java:134)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at bg.barcodes.mobile.routes.java.StatusDatecsPrinter.access$0(StatusDatecsPrinter.java:118)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at bg.barcodes.mobile.routes.java.StatusDatecsPrinter$1.onClick(StatusDatecsPrinter.java:61)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at android.view.View.performClick(View.java:2364)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at android.view.View.onTouchEvent(View.java:4179)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at android.widget.TextView.onTouchEvent(TextView.java:6650)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at android.view.View.dispatchTouchEvent(View.java:3709)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:924)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:924)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:924)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at android.view.ViewGroup.dispatchTouchEvent(ViewGroup.java:924)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchTouchEvent(PhoneWindow.java:1695)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at com.android.internal.policy.impl.PhoneWindow.superDispatchTouchEvent(PhoneWindow.java:1116)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at android.app.Activity.dispatchTouchEvent(Activity.java:2068)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchTouchEvent(PhoneWindow.java:1679)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at android.view.ViewRoot.handleMessage(ViewRoot.java:1708)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at android.os.Handler.dispatchMessage(Handler.java:99)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at android.os.Looper.loop(Looper.java:123)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at android.app.ActivityThread.main(ActivityThread.java:4595)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at java.lang.reflect.Method.invokeNative(Native Method)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at java.lang.reflect.Method.invoke(Method.java:521)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:860)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:618)
05-11 17:36:56.182: E/AndroidRuntime(5458):     at dalvik.system.NativeStart.main(Native Method)
05-11 17:36:56.192: I/dalvikvm(5458): threadid=7: reacting to signal 3
05-11 17:36:56.222: I/dalvikvm(5458): Wrote stack trace to '/data/anr/traces.txt'

Any ideas ?

beware that it may not only be related to the context you are using but also on what thread you are on. Please also provide the stacktrace of the error — Estragon, May 11 '12 at 14:32
You can use [dialogactivity][1] it can help. [1]: http://stackoverflow.com/questions/1979369/android-activity-as-a-dialog — Mufazzal, May 11 '12 at 15:07

score 1 · Answer 1 · answered May 11 '12 at 14:48

don't try to use getApplicationContext(), create MyApplication class, inherited from the Application, then inside that class do the following:

public class MyApplication extends Application {
    private static MyApplication instance;

    @Override
    public void onCreate() {
        super.onCreate();
        instance = this;
        .........
    }

    public static Context getContext() {
        return instance;
    }

After that, you may use MyApplication.getContext() anywhere if you need a context and don't have an Activity lying around.

score 0 · Answer 2 · answered May 11 '12 at 14:41

0

An alert dialog is displayed on above of an Activity, that's why you need an activity's context to initialize a dialog object. So, technically its not possible to show such dialogs without having reference to activity.

answered May 11 '12 at 14:41

waqaslam

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score 0 · Answer 3 · answered May 11 '12 at 14:45

There is no way to interrupt another activity when it is running. However, the sort of functionality that you are looking for would be satisfied through using notifications. This does not show a dialog in front of the running activity, but a user will still be notified when something goes wrong:

http://developer.android.com/guide/topics/ui/notifiers/notifications.html

How to start AlertDialog regardless the context? Android

3 Answers3