android startActivity undefined

Question

I am making a drawing app and would like to share the image. However, I meet an error for the startActivity part, of which the error writes The method startActivity(Intent) is undefined for the type . What does it means and how could it be tackled? Many thanks in advances!!!

EDIT:

posted further code settings for the codes: ActivityA Calling shareImage() in PaintView.

I am not sure whether the Context in this way is ok? Except this newly added sharing function, the code without sharing runs very smoothly.

PaintView

// the main screen that is painted
public class PaintView extends View 
{      
   Context context_new;       
   private boolean isFileAlreadySaved = false;
   String savedFilePath = "";

   private static final float TOUCH_TOLERANCE = 10;
   // other declarations here

   // PaintView constructor initializes the PaintView
   public PaintView(Context context, AttributeSet attrs) 
   {
      super(context, attrs); // pass context to View's constructor
      this.context_new=context;
      paintScreen = new Paint(); // used to display bitmap onto screen

      // set the initial display settings for the painted line
      paintLine = new Paint();
      paintLine.setAntiAlias(true); // smooth edges of drawn line
      paintLine.setColor(Color.BLACK); // default color is black
      paintLine.setStyle(Paint.Style.STROKE); // solid line
      paintLine.setStrokeWidth(5); // set the default line width
      paintLine.setStrokeCap(Paint.Cap.ROUND); // rounded line ends
      pathMap = new HashMap<Integer, Path>();
      previousPointMap = new HashMap<Integer, Point>();
   } // end DoodleView constructor


   public void shareImage()
   {
        Intent share;
        File attachment = null;

        if(isFileAlreadySaved == true)
        {
            attachment = new File(savedFilePath);
            boolean isFileThere = attachment.exists();
            if (isFileThere == true)
            {
                share = new Intent(Intent.ACTION_SEND);
                share.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
                share.putExtra(Intent.EXTRA_STREAM, Uri.fromFile(attachment));
                share.setType("image/png");
                startActivity(Intent.createChooser(share, "Share drawing"));
            }
        }
        else
        {
            Toast.makeText(getContext(), "Please save the image first...", Toast.LENGTH_LONG).show();    
        };
   };

ActivityA:

   public OnClickListener shareButtonListener = new OnClickListener()   
   {
      @Override
      public void onClick(View v) 
      {        
        vibrate();
        PaintView.shareImage(ActivtyA.this);
      };
   };

Logcat:

02-02 16:01:58.230: E/AndroidRuntime(9809):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1992)
02-02 16:01:58.230: E/AndroidRuntime(9809):     at android.app.ActivityThread.access$600(ActivityThread.java:127)
02-02 16:01:58.230: E/AndroidRuntime(9809):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1158)
02-02 16:01:58.230: E/AndroidRuntime(9809):     at android.os.Handler.dispatchMessage(Handler.java:99)
02-02 16:01:58.230: E/AndroidRuntime(9809):     at android.os.Looper.loop(Looper.java:137)
02-02 16:01:58.230: E/AndroidRuntime(9809):     at android.app.ActivityThread.main(ActivityThread.java:4511)
02-02 16:01:58.230: E/AndroidRuntime(9809):     at java.lang.reflect.Method.invokeNative(Native Method)
02-02 16:01:58.230: E/AndroidRuntime(9809):     at java.lang.reflect.Method.invoke(Method.java:511)
02-02 16:01:58.230: E/AndroidRuntime(9809):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:980)
02-02 16:01:58.230: E/AndroidRuntime(9809):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:747)
02-02 16:01:58.230: E/AndroidRuntime(9809):     at dalvik.system.NativeStart.main(Native Method)
02-02 16:01:58.230: E/AndroidRuntime(9809): Caused by: java.lang.NullPointerException
02-02 16:01:58.230: E/AndroidRuntime(9809):     at com.pearmak.drawing.ActivityA.onCreate(ActivityA.java:102)
02-02 16:01:58.230: E/AndroidRuntime(9809):     at android.app.Activity.performCreate(Activity.java:4470)
02-02 16:01:58.230: E/AndroidRuntime(9809):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1052)
02-02 16:01:58.230: E/AndroidRuntime(9809):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1931)
02-02 16:01:58.230: E/AndroidRuntime(9809):     ... 11 more

Answer 1

you will need to pass Activity Context to Non Activity class by using constructor or by changing method to parametrized method as :

public class PaintView extends View 
{      
  Context context_new;
  public PaintView(Context context){
    this.context_new=context;
  }
   //.. your code here
   public void shareImage(Context context)
   {

     context.startActivity(Intent.createChooser(share, "Share drawing"));
     //OR
     //context_new.startActivity(Intent.createChooser(share, "Share drawing"));
      Toast.makeText(context, 
          "Please save the image first...",
                   Toast.LENGTH_LONG).show();   

      //OR
         // Toast.makeText(context_new, 
         // "Please save the image first...",
         //Toast.LENGTH_LONG).show(); 

   }

}

and call shareImage method from Activity as :

PaintView paintview=new PaintView(Your_Current_Activity.this);
paintview.shareImage(Your_Current_Activity.this);

Answer 2

I guess you're trying to call startActivity() from a class that's not your Activity class. The startActivity() method belongs to the Context class, so you either need to call it from your Activity (which extends Context) or pass an instance of Context to this class and use the context.startActivity() call. Hope this helps.

Answer 3

Try out as startActivityForResult(Intent.createChooser(share, "Share drawing"));