CODEWITHSUNDEEP
androidandroid-fragmentsandroid-view
lamp ard
lamp ard

Reputation: 871

How to setContentView in a fragment?

Now I've got this fragment which i want to use setContentView with but so far i cant find how. You can see my case in the code below, im not trying to inflate a layout, im trying to use it with the view called SampleView. So how can I do that?

public class largeImageScroller extends SherlockFragment {
 
// Physical display width and height.
private static int displayWidth = 0;
private static int displayHeight = 0;

/** Called when the activity is first created. */
public View onCreateView(LayoutInflater inflater, ViewGroup group, Bundle saved) {

        getActivity();
        // displayWidth and displayHeight will change depending on screen
        // orientation. To get these dynamically, we should hook onSizeChanged().
        // This simple example uses only landscape mode, so it's ok to get them
        // once on startup and use those values throughout.
        
        Display display = ((WindowManager)
getActivity().getSystemService(Context.WINDOW_SERVICE)).getDefaultDisplay();
        displayWidth = display.getWidth();             
        displayHeight = display.getHeight();    

        // SampleView constructor must be constructed last as it needs the
        // displayWidth and displayHeight we just got.
        setContentView(new SampleView(this));
}

private static class SampleView extends View {
        private static Bitmap bmLargeImage; //bitmap large enough to be scrolled
        private static Rect displayRect = null; //rect we display to
        private Rect scrollRect = null; //rect we scroll over our bitmap with
        private int scrollRectX = 0; //current left location of scroll rect
        private int scrollRectY = 0; //current top location of scroll rect
        private float scrollByX = 0; //x amount to scroll by
        private float scrollByY = 0; //y amount to scroll by
        private float startX = 0; //track x from one ACTION_MOVE to the next
        private float startY = 0; //track y from one ACTION_MOVE to the next

        public SampleView(Context context) {
                super(context);

                // Destination rect for our main canvas draw. It never changes.
                displayRect = new Rect(0, 0, displayWidth, displayHeight);
                // Scroll rect: this will be used to 'scroll around' over the
                // bitmap in memory. Initialize as above.
                scrollRect = new Rect(0, 0, displayWidth, displayHeight);

                // Load a large bitmap into an offscreen area of memory.
                bmLargeImage = BitmapFactory.decodeResource(getResources(),
                        R.drawable.ground_floor_b);
        }
       
        @Override
        public boolean onTouchEvent(MotionEvent event) {

                switch (event.getAction()) {
                        case MotionEvent.ACTION_DOWN:
                                // Remember our initial down event location.
                                startX = event.getRawX();
                                startY = event.getRawY();
                                break;

                        case MotionEvent.ACTION_MOVE:
                                float x = event.getRawX();
                                float y = event.getRawY();
                                // Calculate move update. This will happen many times
                                // during the course of a single movement gesture.
                                scrollByX = x - startX; //move update x increment
                                scrollByY = y - startY; //move update y increment
                                startX = x; //reset initial values to latest
                                startY = y;
                                invalidate(); //force a redraw
                                break;
                }
                return true; //done with this event so consume it
        }

        @Override
        protected void onDraw(Canvas canvas) {

                // Our move updates are calculated in ACTION_MOVE in the opposite direction
                // from how we want to move the scroll rect. Think of this as dragging to
                // the left being the same as sliding the scroll rect to the right.
                int newScrollRectX = scrollRectX - (int)scrollByX;
                int newScrollRectY = scrollRectY - (int)scrollByY;

                // Don't scroll off the left or right edges of the bitmap.
                if (newScrollRectX < 0)
                        newScrollRectX = 0;
                else if (newScrollRectX > (bmLargeImage.getWidth() - displayWidth))
                        newScrollRectX = (bmLargeImage.getWidth() - displayWidth);

                // Don't scroll off the top or bottom edges of the bitmap.
                if (newScrollRectY < 0)
                        newScrollRectY = 0;
                else if (newScrollRectY > (bmLargeImage.getHeight() - displayHeight))
                        newScrollRectY = (bmLargeImage.getHeight() - displayHeight);

                // We have our updated scroll rect coordinates, set them and draw.
                scrollRect.set(newScrollRectX, newScrollRectY,
                        newScrollRectX + displayWidth, newScrollRectY + displayHeight);
                Paint paint = new Paint();
                canvas.drawBitmap(bmLargeImage, scrollRect, displayRect, paint);

                // Reset current scroll coordinates to reflect the latest updates,
                // so we can repeat this update process.
                scrollRectX = newScrollRectX;
                scrollRectY = newScrollRectY;
        }
}
}

Upvotes: 40

Views: 108675

Answers (5)

Manish Patel
Manish Patel

Reputation: 33

As explained already, you need to return the view in case of fragments. But still if you want to use it just like setContentView(), you can do so in following way.

1.Put this code snippet wherever you had to put setContentView()

View v = inflater.inflate(R.layout.activity_home, container, false);

2.Now if you want to access something from xml file, you can do so by using

chart = v.findViewById(R.id.chart);

3. And in the end of OnCreateView() you will have to put 

return v;

Full example : 

  public View onCreateView(LayoutInflater inflater, ViewGroup container,
                         Bundle savedInstanceState) {


    View v = inflater.inflate(R.layout.activity_home, container, false);

    chart = v.findViewById(R.id.chart);

    return v;
   }

Upvotes: 3

biegleux
biegleux

Reputation: 13247

Also it's not safe to call getActivity() from onCreateView(). Make sure you call it in or after onActivityCreated(), as at this point your Fragment is fully associated with the Activity. Check Fragment's lifecycle.

Fragments

Upvotes: 6

Sankar
Sankar

Reputation: 1691

In activities we need to set the view using setContentView(R.layout.main)

Where as in fragments we need to override onCreateView() to set the desired view.

Upvotes: 1

bjorncs
bjorncs

Reputation: 1270

Return the view instance you want to use:

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
        return inflater.inflate(R.layout.ads_tab, container, false);
    }

Upvotes: 33

waqaslam
waqaslam

Reputation: 68187

You dont call setContentView in fragments, in fact you need to return a View from onCreateView.

Try replacing:

setContentView(new SampleView(this));

With this:

return new SampleView(this);

Upvotes: 56

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