Re: [android-developers] How to solve this problem: Close Force Error when trying to populate viewStub

Kostya Vasilyev Sun, 01 Aug 2010 08:50:27 -0700

Aha, now we're on to something.

1 - I think it does, but the inflated content is such that you don't seeit. Try playing with the inflated layout's background color, and withViewStub's width and height (maybe set to fixed values for debugging,like both 200dp).

2 - Inflating a ViewStub removes the stub, and replaces it with theinflated content. So the second time through the ViewStub isn't thereanymore, and the code crashes since the return value offindViewById(R.id.stub_exposure) is null.

You need to be able to tell apart the first and second time through thiscode. I see you are saving the inflated layout in "importStub", maybecheck it for null, and if it's not null, then the view is alreadyinflated. Or check the return value of findViewById(R.id.stub_exposure).

"@+id/NO_ID" does not have any special meaning, it's just an id, you'drefer to it as "R.id.NO_ID". It certainly doesn't change the behavior ofViewStub.inflate().


-- Kostya

01.08.2010 19:30, Victoria Busse пишет:

Yes, I know that my try catch was wrong, but I corrected it eventually...

I think you are right the error is always displayed when I press thebutton a second time...but that brings me to two new problems orquestions:


1. Why doesn't the inflated View or layout show up?

2. How can I allow the button to be clicked several times and everytime calling the ViewStub and its inflated layout. (I already changedinflatedId to NO_ID, but apparently that doesn't do the trick)


<ViewStub
android:id="@+id/stub_exposure"
android:inflatedId="@+id/NO_ID"
android:layout="@layout/exposureview"
android:layout_width="fill_parent"
android:layout_height="wrap_content"
android:background="#77000000">
</ViewStub>

On Sun, Aug 1, 2010 at 4:07 PM, Kostya Vasilyev <[email protected]<mailto:[email protected]>> wrote:


    Victoria,

    Has the ViewStub already been inflated by any chance? That is,
    maybe this is the second time through you're clicking the button?

    If so, you should know that inflating a ViewStub removes it from
    the hierarchy and replaces it with the layout you provide with
    android:layout, giving it the id set by android:inflatedId.

    Also, your try/catch block is wrong, it should be inside the
    onClick listener - think about it, the exception happens when you
    click the button, not when you set the onClick handler.


    btnExposure.setOnClickListener(new OnClickListener()
            {
    @Override
    public void onClick(View v) {
    *try {*
    ViewStub stub = (ViewStub) findViewById(R.id.stub_exposure);
    importStub = stub.inflate();
    *}catch (Exception e){
                    // pass "e" to Log.e to see full stack trace in logcat
    *
    * Log.e("ERROR", "Error in Code:" +e.toString(), e);*
    *} *
    }
            });

    You also need to modify the layout to be inflated -the way it is
    now, both views are on top of one another. This is the fix:

    <TextView
        android:id="@+id/text_view"

    <SeekBar
        android:layout_below="@id/text_view

    And last but not least, I think this is the actual error:

    android:text="@+String/hello"

    There is no "+" notation for strings, and it's "string" not
    "String" anyway. You can do either

    android:text="@string/hello"

    or

    android:text="Hello"

    -- Kostya

    01.08.2010 16:27, Victoria Busse пишет:

    Okay I got the "Source" of the error: the try and catch returned
     that the Null Pointer Exception derives from this part as you
    already suspected:

    ViewStub stub = (ViewStub) findViewById(R.id.stub_exposure);
     importStub = stub.inflate();
    But I don't understand why it should be null as I followed the
    examples I found on the web... e.g. this here:
    http://developer.android.com/reference/android/view/ViewStub.html

    And this is the code in the xml, in which I call the ViewStub:

    <ViewStub
    android:id="@+id/stub_exposure"
    android:inflatedId="@+id/stub_exposure_view"
    android:layout="@layout/exposureview"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:background="#77000000">
    </ViewStub>

    And here is the according layout xml for the inflated View, the
    exposureview.xml:

    <?xml version="1.0" encoding="utf-8"?>
    <RelativeLayout
     xmlns:android="http://schemas.android.com/apk/res/android";
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    >
    <TextView
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:text="@+String/hello"
    ></TextView>
    <SeekBar
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:thumb="@drawable/seek_thumb"
    android:progress="50"
    android:max="100">
    </SeekBar>

    </RelativeLayout>



    2010/8/1 Victoria Busse <[email protected]
    <mailto:[email protected]>>

        mhmmm, I tried

        try{
                btnExposure.setOnClickListener(new OnClickListener()
                {
        @Override
        public void onClick(View v) {
        ViewStub stub = (ViewStub) findViewById(R.id.stub_exposure);
        importStub = stub.inflate();
        }
                });}catch (Exception e){
        Log.e("ERROR", "Error in Code:" +e.toString());
                }

        but I don't get any output at all...

        2010/8/1 Kostya Vasilyev <[email protected]
        <mailto:[email protected]>>

            Victoria,

            Judging by logcat, it looks like "stub" variable, the
            result of calling findViewById(R.id.stub_exposure) is
            null. You should check this in the debugger.

            -- Kostya

            01.08.2010 13:46, Victoria Busse пишет:

            Okay found the problem, I simply forgot to define the
            button's View  btnExposure = (ImageButton)
            findViewById(R.id.button_exposure);
            So this - quite simple - problem's solved, but now I got
            at new NullPointerException at
            
com.mobilevideoeditor.moved.EditorView$1.onClick(EditorView.java:54),
            which is importStub = ((ViewStub)
            findViewById(R.id.stub_exposure)).inflate();
            And this is what I don't really understand because I am
            not familiar with ViewStubs yet...

            I also tried ViewStub stub = (ViewStub)
            findViewById(R.id.stub_exposure);
            importStub = stub.inflate();
            but again I get the Null Pointer Exception at importStub
            = stub.inflate();

            Could there be s.th <http://s.th> wrong with the
            exposureview.xml that I use to inflate the stub??


            2010/8/1 Victoria Busse <[email protected]
            <mailto:[email protected]>>

                Here is the Logcat:

                08-01 08:17:11.984: ERROR/AndroidRuntime(223):
                Uncaught handler: thread main exiting due to
                uncaught exception
                08-01 08:17:11.994: ERROR/AndroidRuntime(223):
                java.lang.RuntimeException: Unable to start activity
                
ComponentInfo{com.mobilevideoeditor.moved/com.mobilevideoeditor.moved.EditorView}:
                java.lang.NullPointerException