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androidandroid-layoutandroid-listviewandroid-custom-viewandroid-scrollview

How to build Two Synchronous ListView with Dynamic Contents


I want to create a ScrollView which has a dynamic content with two columns in itself.

And items of right column are connected to items of left column cross-positioned. (Like this first column item y-coordinates:[(0,100),(100,200),(200,300)] -- second column item y-coordinates:[(50,150),(150,250)])

Using one ScrollView or a ListView is impossible because they cannot have two columns like that cross positioned as I know. So, I have two solutions. These solution approaches have different problems.

Here is my first solution:
-A dynamic custom view inside a ScrollView.
-The problem with this approach is I cannot figure out how to update the ScrollView and Dynamic Custom View, so it does not scroll.

My second solution:
-Two seperate connected listview (If you slide one, other one slides automatically to the same position synchronously).
-This solutions problem is I cant find out a way to connect them to each other.

Any help will be appreciated.


Solution

  • For any person who might need the answer, I've found the solution in here. I improved this with that (which is incorrect)(actually I fixed it). And here is my final solution:

    MyScrollView.java

    public class MyScrollView extends ScrollView implements IScrollListener {
    
        private static final String TAG = "MyScrollView";
        private IScrollListener listener;
    
        public MyScrollView(Context context) {
            super(context);
        }
    
        public MyScrollView(Context context, AttributeSet attrs) {
            super(context, attrs);
        }
    
        public MyScrollView(Context context, AttributeSet attrs, int defStyleAttr) {
            super(context, attrs, defStyleAttr);
        }
    
        public void setScrollViewListener(IScrollListener listener) {
            this.listener = listener;
        }
    
        @Override
        protected void onScrollChanged(int x, int y, int oldX, int oldY) {
            super.onScrollChanged(x, y, oldX, oldY);
            if (listener != null) {
                listener.onScrollChanged(this, x, y, oldX, oldY);
            } else {
                Log.i(TAG, "asdasd");
            }
        }
    
        @Override
        public void onScrollChanged(IScrollListener scrollView, int x, int y, int oldX, int oldY) {
            super.onScrollChanged(x, y, oldX, oldY);
            if (listener != null) {
                listener.onScrollChanged(this, x, y, oldX, oldY);
            } else {
                Log.i(TAG, "asdasd");
            }
        }
    }
    

    MyActivity.java

    public class MyActivity extends AppCompatActivity implements IScrollListener {
        @Override
        protected void onCreate(Bundle savedInstanceState) {
    
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_multi_position);
    
            .
            .
            .
    
            scrollViewLeft = (MyScrollView) this.findViewById(R.id.scrollViewLeft);
            scrollViewRight = (MyScrollView) this.findViewById(R.id.scrollViewRight);
    
            .
            .
    
            scrollViewLeft.setScrollViewListener(this);
            scrollViewRight.setScrollViewListener(this);
    
            .
            .
            LayoutInflater vi = (LayoutInflater) getApplicationContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            View viewLeft = vi.inflate(R.layout.target_item, null);
            View viewRight = vi.inflate(R.layout.target_item_right, null);
    
            // insert into left view
            ViewGroup insertPointLeft = (ViewGroup) findViewById(R.id.leftLinearLayout);
            insertPointLeft.addView(viewLeft, 0, new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));
    
            // insert into right view
            ViewGroup insertPointRight = (ViewGroup) findViewById(R.id.rightLinearLayout);
            insertPointRight.addView(viewRight, targets.size(), new ViewGroup.LayoutParams(ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.WRAP_CONTENT));
    
            // fill in any details dynamically here
            TextView number = (TextView) viewLeft.findViewById(R.id.number);
            number.setText("1");
            TextView name = (TextView) viewLeft.findViewById(R.id.name);
            name.setText("Muhammed Aydogan");
    
            // fill in any details dynamically here
            TextView number2 = (TextView) viewRight.findViewById(R.id.number);
            number2.setText("2");
            TextView name2 = (TextView) viewRight.findViewById(R.id.name);
            name2.setText("Muhammed Aydogan");*/
        }
    
        @Override
        public void onScrollChanged(IScrollListener scrollView, int x, int y, int oldX, int oldY) {
            if (scrollViewLeft.equals(scrollView)) {
                scrollViewRight.scrollTo(x, y);
            } else if (scrollViewRight.equals(scrollView)) {
                scrollViewLeft.scrollTo(x, y);
            }
        }
    }
    

    IScrollListener.java

    public interface IScrollListener {
        void onScrollChanged(IScrollListener scrollView, int x, int y, int oldX, int oldY);
    }