How to implement HorizontalScrollView like Gallery?

Question

I want to implement Horizontal ScrollView with some features of Gallery, <

Answer 1

Try this code:

activity_main.xml

grid_item.xml

MainActivity.java

import java.util.ArrayList;

import android.app.Activity;
import android.graphics.Rect;
import android.os.Bundle;
import android.os.Handler;
import android.view.Display;
import android.view.GestureDetector;
import android.view.GestureDetector.SimpleOnGestureListener;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnTouchListener;
import android.widget.HorizontalScrollView;
import android.widget.LinearLayout;
import android.widget.LinearLayout.LayoutParams;

public class MainActivity extends Activity {

LinearLayout asthmaActionPlan, controlledMedication, asNeededMedication,
        rescueMedication, yourSymtoms, yourTriggers, wheezeRate, peakFlow;
LayoutParams params;
LinearLayout next, prev;
int viewWidth;
GestureDetector gestureDetector = null;
HorizontalScrollView horizontalScrollView;
ArrayList layouts;
int parentLeft, parentRight;
int mWidth;
int currPosition, prevPosition;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    prev = (LinearLayout) findViewById(R.id.prev);
    next = (LinearLayout) findViewById(R.id.next);
    horizontalScrollView = (HorizontalScrollView) findViewById(R.id.hsv);
    gestureDetector = new GestureDetector(new MyGestureDetector());
    asthmaActionPlan = (LinearLayout) findViewById(R.id.asthma_action_plan);
    controlledMedication = (LinearLayout) findViewById(R.id.controlled_medication);
    asNeededMedication = (LinearLayout) findViewById(R.id.as_needed_medication);
    rescueMedication = (LinearLayout) findViewById(R.id.rescue_medication);
    yourSymtoms = (LinearLayout) findViewById(R.id.your_symptoms);
    yourTriggers = (LinearLayout) findViewById(R.id.your_triggers);
    wheezeRate = (LinearLayout) findViewById(R.id.wheeze_rate);
    peakFlow = (LinearLayout) findViewById(R.id.peak_flow);

    Display display = getWindowManager().getDefaultDisplay();
    mWidth = display.getWidth(); // deprecated
    viewWidth = mWidth / 3;
    layouts = new ArrayList();
    params = new LayoutParams(viewWidth, LayoutParams.WRAP_CONTENT);

    asthmaActionPlan.setLayoutParams(params);
    controlledMedication.setLayoutParams(params);
    asNeededMedication.setLayoutParams(params);
    rescueMedication.setLayoutParams(params);
    yourSymtoms.setLayoutParams(params);
    yourTriggers.setLayoutParams(params);
    wheezeRate.setLayoutParams(params);
    peakFlow.setLayoutParams(params);

    layouts.add(asthmaActionPlan);
    layouts.add(controlledMedication);
    layouts.add(asNeededMedication);
    layouts.add(rescueMedication);
    layouts.add(yourSymtoms);
    layouts.add(yourTriggers);
    layouts.add(wheezeRate);
    layouts.add(peakFlow);

    next.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            new Handler().postDelayed(new Runnable() {
                public void run() {
                    horizontalScrollView.smoothScrollTo(
                            (int) horizontalScrollView.getScrollX()
                                    + viewWidth,
                            (int) horizontalScrollView.getScrollY());
                }
            }, 100L);
        }
    });

    prev.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            new Handler().postDelayed(new Runnable() {
                public void run() {
                    horizontalScrollView.smoothScrollTo(
                            (int) horizontalScrollView.getScrollX()
                                    - viewWidth,
                            (int) horizontalScrollView.getScrollY());
                }
            }, 100L);
        }
    });

    horizontalScrollView.setOnTouchListener(new OnTouchListener() {
        @Override
        public boolean onTouch(View v, MotionEvent event) {
            if (gestureDetector.onTouchEvent(event)) {
                return true;
            }
            return false;
        }
    });
}

class MyGestureDetector extends SimpleOnGestureListener {
    @Override
    public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
            float velocityY) {
        if (e1.getX() < e2.getX()) {
            currPosition = getVisibleViews("left");
        } else {
            currPosition = getVisibleViews("right");
        }

        horizontalScrollView.smoothScrollTo(layouts.get(currPosition)
                .getLeft(), 0);
        return true;
    }
}

public int getVisibleViews(String direction) {
    Rect hitRect = new Rect();
    int position = 0;
    int rightCounter = 0;
    for (int i = 0; i < layouts.size(); i++) {
        if (layouts.get(i).getLocalVisibleRect(hitRect)) {
            if (direction.equals("left")) {
                position = i;
                break;
            } else if (direction.equals("right")) {
                rightCounter++;
                position = i;
                if (rightCounter == 2)
                    break;
            }
        }
    }
    return position;
}
}

Let me know if any issue enjoy...