How to implement HorizontalScrollView like Gallery?

Jayesh picture Jayesh · Sep 6, 2013 · Viewed 183.6k times · Source

I want to implement Horizontal ScrollView with some features of Gallery, enter image description here

In Gallery the scroll made at some distance it arrange in pair, i.e If we have three images shown in screen, clicking last image will arrange at center.

How would I implement HorizontalSCrollView as mentioned?

Answer

Vijju picture Vijju · Oct 18, 2013

Try this code:

activity_main.xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="fill_parent"
android:layout_height="100dip"
tools:context=".MainActivity" >
<HorizontalScrollView
    android:id="@+id/hsv"
    android:layout_width="fill_parent"
    android:layout_height="wrap_content"
    android:layout_alignParentTop="true"
    android:fillViewport="true"
    android:measureAllChildren="false"
    android:scrollbars="none" >
    <LinearLayout
        android:id="@+id/innerLay"
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:gravity="center_vertical"
        android:orientation="horizontal" >
        <LinearLayout
            android:id="@+id/asthma_action_plan"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:orientation="vertical" >
            <RelativeLayout
                android:layout_width="fill_parent"
                android:layout_height="match_parent" >
                <ImageView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:src="@drawable/action_plan" />
                <TextView
                    android:layout_width="0.2dp"
                    android:layout_height="fill_parent"
                    android:layout_alignParentRight="true"
                    android:background="@drawable/ln" />
            </RelativeLayout>
        </LinearLayout>
        <LinearLayout
            android:id="@+id/controlled_medication"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:orientation="vertical" >
            <RelativeLayout
                android:layout_width="fill_parent"
                android:layout_height="match_parent" >
                <ImageView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:src="@drawable/controlled" />
                <TextView
                    android:layout_width="0.2dp"
                    android:layout_height="fill_parent"
                    android:layout_alignParentRight="true"
                    android:background="@drawable/ln" />
            </RelativeLayout>
        </LinearLayout>
        <LinearLayout
            android:id="@+id/as_needed_medication"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:orientation="vertical" >
            <RelativeLayout
                android:layout_width="fill_parent"
                android:layout_height="match_parent"
                android:orientation="horizontal" >
                <ImageView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:src="@drawable/as_needed" />
                <TextView
                    android:layout_width="0.2dp"
                    android:layout_height="fill_parent"
                    android:layout_alignParentRight="true"
                    android:background="@drawable/ln" />
            </RelativeLayout>
        </LinearLayout>
        <LinearLayout
            android:id="@+id/rescue_medication"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:orientation="vertical" >
            <RelativeLayout
                android:layout_width="fill_parent"
                android:layout_height="match_parent" >
                <ImageView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:src="@drawable/rescue" />
                <TextView
                    android:layout_width="0.2dp"
                    android:layout_height="fill_parent"
                    android:layout_alignParentRight="true"
                    android:background="@drawable/ln" />
            </RelativeLayout>
        </LinearLayout>
        <LinearLayout
            android:id="@+id/your_symptoms"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:orientation="vertical" >
            <RelativeLayout
                android:layout_width="fill_parent"
                android:layout_height="match_parent" >
                <ImageView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:src="@drawable/symptoms" />
                <TextView
                    android:layout_width="0.2dp"
                    android:layout_height="fill_parent"
                    android:layout_alignParentRight="true"
                    android:background="@drawable/ln" />
            </RelativeLayout>
        </LinearLayout>
        <LinearLayout
            android:id="@+id/your_triggers"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:orientation="vertical" >
            <RelativeLayout
                android:layout_width="fill_parent"
                android:layout_height="match_parent" >
                <ImageView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:src="@drawable/triggers" />
                <TextView
                    android:layout_width="0.2dp"
                    android:layout_height="fill_parent"
                    android:layout_alignParentRight="true"
                    android:background="@drawable/ln" />
            </RelativeLayout>
        </LinearLayout>
        <LinearLayout
            android:id="@+id/wheeze_rate"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:orientation="vertical" >
            <RelativeLayout
                android:layout_width="fill_parent"
                android:layout_height="match_parent" >
                <ImageView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:src="@drawable/wheeze_rate" />
                <TextView
                    android:layout_width="0.2dp"
                    android:layout_height="fill_parent"
                    android:layout_alignParentRight="true"
                    android:background="@drawable/ln" />
            </RelativeLayout>
        </LinearLayout>
        <LinearLayout
            android:id="@+id/peak_flow"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:gravity="center"
            android:orientation="vertical" >
            <RelativeLayout
                android:layout_width="fill_parent"
                android:layout_height="match_parent" >
                <ImageView
                    android:layout_width="wrap_content"
                    android:layout_height="wrap_content"
                    android:src="@drawable/peak_flow" />
                <TextView
                    android:layout_width="0.2dp"
                    android:layout_height="fill_parent"
                    android:layout_alignParentRight="true"
                    android:background="@drawable/ln" />
            </RelativeLayout>
        </LinearLayout>
    </LinearLayout>
</HorizontalScrollView>
<TextView
    android:layout_width="fill_parent"
    android:layout_height="0.2dp"
    android:layout_alignParentRight="true"
    android:layout_below="@+id/hsv"
    android:background="@drawable/ln" />
<LinearLayout
    android:id="@+id/prev"
    android:layout_width="wrap_content"
    android:layout_height="fill_parent"
    android:layout_alignParentLeft="true"
    android:layout_centerVertical="true"
    android:paddingLeft="5dip"
    android:paddingRight="5dip"
    android:descendantFocusability="blocksDescendants" >
    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_vertical"
        android:src="@drawable/prev_arrow" />
</LinearLayout>
<LinearLayout
    android:id="@+id/next"
    android:layout_width="wrap_content"
    android:layout_height="fill_parent"
    android:layout_alignParentRight="true"
    android:layout_centerVertical="true"
    android:paddingLeft="5dip"
    android:paddingRight="5dip"
    android:descendantFocusability="blocksDescendants" >
    <ImageView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:layout_gravity="center_vertical"
        android:src="@drawable/next_arrow" />
</LinearLayout>
</RelativeLayout>

grid_item.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:orientation="vertical" >
<ImageView
    android:id="@+id/imageView1"
    android:layout_width="fill_parent"
    android:layout_height="100dp"
    android:src="@drawable/ic_launcher" />
</LinearLayout>

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<LinearLayout> 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<LinearLayout>();
    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...