Skip to main content

Zoom Image - Android Tutorial

Here we are going to see how to zoom an image in Imageview

Will see it through a sample

1. Create xml with an ImageView
<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout 
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <LinearLayout
        android:layout_width="200dp"
        android:layout_height="200dp"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintLeft_toLeftOf="parent"
        app:layout_constraintRight_toRightOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        android:orientation="vertical">

        <LinearLayout
            android:id="@+id/progress_one"
            android:layout_width="match_parent"
            android:layout_height="200dp"
            android:visibility="visible">

            <ProgressBar
                android:layout_width="match_parent"
                android:layout_height="50dp"
                android:layout_gravity="center"
                android:indeterminateDrawable="@drawable/splash_loading">
            </ProgressBar>

        </LinearLayout>

        <ImageView
            android:id="@+id/id_imgview"
            android:layout_width="match_parent"
            android:layout_height="200dp"
            android:scaleType="fitXY"
            android:adjustViewBounds="true"/>

    </LinearLayout>

</androidx.constraintlayout.widget.ConstraintLayout>

2. MainActivity.java
public class MainActivity extends AppCompatActivity {

    ImageView imageView;
    LinearLayout progressll;
    String imgUrl = "https://i2.wp.com/allpicts.in/wp-content/uploads/2017/02/pictures-of-the-solar-system.jpg";


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

        imageView = findViewById(R.id.id_imgview);
        progressll = findViewById(R.id.progress_one);

        //callSetImageFun
        setImage(imageView, imgUrl, progressll);
        //callImageviewClick
        imageView.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                fullPreviewScreen(imgUrl, MainActivity.this);
            }
        });
    }

    private void setImage(ImageView ximageView, String imgUrl, final LinearLayout xllProgress) {
        RequestOptions options = new RequestOptions()
                .override(imageView.getMeasuredWidth(),200);

        Glide.with(getApplicationContext()).load(imgUrl).apply(options)
                .listener(new RequestListener<Drawable>() {
                    @Override
                    public boolean onLoadFailed(@Nullable GlideException e, Object model, Target<Drawable> target, boolean isFirstResource) {
                        xllProgress.setVisibility(View.GONE);
                        return false;
                    }

                    @Override
                    public boolean onResourceReady(Drawable resource, Object model, Target<Drawable> target, DataSource dataSource, boolean isFirstResource) {
                        xllProgress.setVisibility(View.GONE);
                        return false;
                    }
                })
                .into(ximageView);
    }

    private void fullPreviewScreen(String ximgurl, Context xcontext) {
        final Dialog dialog = new Dialog(xcontext);
        dialog.requestWindowFeature(Window.FEATURE_NO_TITLE);
        dialog.setContentView(R.layout.dialog_image);
        dialog.getWindow().setBackgroundDrawable(new ColorDrawable(xcontext.getResources().getColor(R.color.color_trans_semi)));
        WindowManager wm = (WindowManager)xcontext.getSystemService(Context.WINDOW_SERVICE);
        Display display = wm.getDefaultDisplay();
        int width = display.getWidth();
        int height = display.getHeight() * 80 / 100;
        dialog.getWindow().setLayout(WindowManager.LayoutParams.MATCH_PARENT, height);

        ImageView imgClose = dialog.findViewById(R.id.idClose);
        TouchImageView imageView = dialog.findViewById(R.id.img);
        RequestOptions options = new RequestOptions()
                .override(imageView.getMeasuredWidth(),150);

        Glide.with(xcontext).load(ximgurl).apply(options).into(imageView);

        imgClose.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                dialog.dismiss();
            }
        });

        dialog.show();
    }
}

3.dialog_image.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">

    <FrameLayout
        android:layout_width="match_parent"
        android:layout_height="match_parent">

        <com.mrbrown.zoomimage.TouchImageView
            android:id="@+id/img"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:layout_gravity="center"
            android:adjustViewBounds="true"
            android:layout_marginLeft="5dp"
            android:layout_marginRight="5dp"
            android:gravity="center"/>

        <ImageView
            android:id="@+id/idClose"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_gravity="bottom|center"
            android:padding="10dp"
            android:src="@drawable/cancel"
            android:clickable="true"
            android:tint="#ffffff"/>

    </FrameLayout>

</LinearLayout>

4. TouchImageView
public class TouchImageView extends AppCompatImageView {

    Matrix matrix;
    // We can be in one of these 3 states
    static final int NONE = 0;
    static final int DRAG = 1;
    static final int ZOOM = 2;

    int mode = NONE;

    // Remember some things for zooming
    PointF last = new PointF();
    PointF start = new PointF();
    float minScale = 1f;
    float maxScale = 3f;
    float[] m;
    int viewWidth, viewHeight;

    static final int CLICK = 3;

    float saveScale = 1f;

    protected float origWidth, origHeight;

    int oldMeasuredWidth, oldMeasuredHeight;

    ScaleGestureDetector mScaleDetector;

    Context context;

    public TouchImageView(Context context) {
        super(context);
        sharedConstructing(context);
    }

    public TouchImageView(Context context, AttributeSet attrs) {
        super(context, attrs);
        sharedConstructing(context);
    }

    private void sharedConstructing(Context context) {

        super.setClickable(true);

        this.context = context;

        mScaleDetector = new ScaleGestureDetector(context, new ScaleListener());

        matrix = new Matrix();

        m = new float[9];

        setImageMatrix(matrix);

        setScaleType(ImageView.ScaleType.MATRIX);

        setOnTouchListener(new View.OnTouchListener() {

            @Override
            public boolean onTouch(View v, MotionEvent event) {

                mScaleDetector.onTouchEvent(event);

                PointF curr = new PointF(event.getX(), event.getY());

                switch (event.getAction()) {

                    case MotionEvent.ACTION_DOWN:

                        last.set(curr);

                        start.set(last);

                        mode = DRAG;

                        break;

                    case MotionEvent.ACTION_MOVE:

                        if (mode == DRAG) {

                            float deltaX = curr.x - last.x;

                            float deltaY = curr.y - last.y;

                            float fixTransX = getFixDragTrans(deltaX, viewWidth, origWidth * saveScale);

                            float fixTransY = getFixDragTrans(deltaY, viewHeight, origHeight * saveScale);

                            matrix.postTranslate(fixTransX, fixTransY);

                            fixTrans();

                            last.set(curr.x, curr.y);

                        }

                        break;

                    case MotionEvent.ACTION_UP:

                        mode = NONE;

                        int xDiff = (int) Math.abs(curr.x - start.x);

                        int yDiff = (int) Math.abs(curr.y - start.y);

                        if (xDiff < CLICK && yDiff < CLICK)

                            performClick();

                        break;

                    case MotionEvent.ACTION_POINTER_UP:

                        mode = NONE;

                        break;

                }

                setImageMatrix(matrix);

                invalidate();

                return true; // indicate event was handled

            }

        });
    }

    public void setMaxZoom(float x) {

        maxScale = x;

    }

    private class ScaleListener extends ScaleGestureDetector.SimpleOnScaleGestureListener {

        @Override
        public boolean onScaleBegin(ScaleGestureDetector detector) {

            mode = ZOOM;

            return true;

        }

        @Override
        public boolean onScale(ScaleGestureDetector detector) {

            float mScaleFactor = detector.getScaleFactor();

            float origScale = saveScale;

            saveScale *= mScaleFactor;

            if (saveScale > maxScale) {

                saveScale = maxScale;

                mScaleFactor = maxScale / origScale;

            } else if (saveScale < minScale) {

                saveScale = minScale;

                mScaleFactor = minScale / origScale;

            }

            if (origWidth * saveScale <= viewWidth || origHeight * saveScale <= viewHeight)

                matrix.postScale(mScaleFactor, mScaleFactor, viewWidth / 2, viewHeight / 2);

            else

                matrix.postScale(mScaleFactor, mScaleFactor, detector.getFocusX(), detector.getFocusY());

            fixTrans();

            return true;

        }

    }

    void fixTrans() {

        matrix.getValues(m);

        float transX = m[Matrix.MTRANS_X];

        float transY = m[Matrix.MTRANS_Y];

        float fixTransX = getFixTrans(transX, viewWidth, origWidth * saveScale);

        float fixTransY = getFixTrans(transY, viewHeight, origHeight * saveScale);

        if (fixTransX != 0 || fixTransY != 0)

            matrix.postTranslate(fixTransX, fixTransY);

    }



    float getFixTrans(float trans, float viewSize, float contentSize) {

        float minTrans, maxTrans;

        if (contentSize <= viewSize) {

            minTrans = 0;

            maxTrans = viewSize - contentSize;

        } else {

            minTrans = viewSize - contentSize;

            maxTrans = 0;

        }

        if (trans < minTrans)

            return -trans + minTrans;

        if (trans > maxTrans)

            return -trans + maxTrans;

        return 0;

    }

    float getFixDragTrans(float delta, float viewSize, float contentSize) {

        if (contentSize <= viewSize) {

            return 0;

        }

        return delta;

    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {

        super.onMeasure(widthMeasureSpec, heightMeasureSpec);

        viewWidth = View.MeasureSpec.getSize(widthMeasureSpec);

        viewHeight = View.MeasureSpec.getSize(heightMeasureSpec);

        //
        // Rescales image on rotation
        //
        if (oldMeasuredHeight == viewWidth && oldMeasuredHeight == viewHeight

                || viewWidth == 0 || viewHeight == 0)

            return;

        oldMeasuredHeight = viewHeight;

        oldMeasuredWidth = viewWidth;

        if (saveScale == 1) {

            //Fit to screen.

            float scale;

            Drawable drawable = getDrawable();

            if (drawable == null || drawable.getIntrinsicWidth() == 0 || drawable.getIntrinsicHeight() == 0)

                return;

            int bmWidth = drawable.getIntrinsicWidth();

            int bmHeight = drawable.getIntrinsicHeight();

            Log.d("bmSize", "bmWidth: " + bmWidth + " bmHeight : " + bmHeight);

            float scaleX = (float) viewWidth / (float) bmWidth;

            float scaleY = (float) viewHeight / (float) bmHeight;

            scale = Math.min(scaleX, scaleY);

            matrix.setScale(scale, scale);

            // Center the image

            float redundantYSpace = (float) viewHeight - (scale * (float) bmHeight);

            float redundantXSpace = (float) viewWidth - (scale * (float) bmWidth);

            redundantYSpace /= (float) 2;

            redundantXSpace /= (float) 2;

            matrix.postTranslate(redundantXSpace, redundantYSpace);

            origWidth = viewWidth - 2 * redundantXSpace;

            origHeight = viewHeight - 2 * redundantYSpace;

            setImageMatrix(matrix);

        }

        fixTrans();

    }
}

5. Don't forget to give Internet Permission in Manifest

________________________________________________________________________

Happy Coding...

Comments

Popular posts from this blog

Add custom font in Android using Calligraphy library

Are you fed up of Custom Views to set fonts? Or traversing the ViewTree to find TextViews? Sometime we want some other font for our Android application then you can add custom font in Android using Calligraphy library . Dependency Include the dependency Download (.aar) dependencies { compile ‘uk.co.chrisjenx:calligraphy:2.2.0’ } Add Fonts Add your custom fonts to assets/ . All font definitions are relative to this path. On Assets you should right-click New Directory, call it "fonts". In the finder put the .ttf  or .otf  font files in there. Create Class Create a class that extends Application and write this code public class App extends Application { @Override public void onCreate() { super.onCreate(); CalligraphyConfig.initDefault(new CalligraphyConfig.Builder() .setDefaultFontPath("your font path") .setFontAttrId(...

Bluetooth Chat Application - Android Tutorial

In this tutorial, we will see about how to design an Android layout for chat application using Chat Bubbles  and the main part is chat via Bluetooth . Main objective of this post is to give an idea about how to allow two-way text chat over Bluetooth in android. Bubbles: Chat bubbles are background image that expands horizontally and vertically as required based on the message posted. Bubbles are Nine-patch Images. Image Nine-patch Image In creating Android chat bubbles, nine-patch image plays a crucial role.  Nine-patch image  is a bitmap which stretches to fit the content posted in the View where it is applied as a background. A NinePatch drawable is a standard PNG image that includes an extra 1-pixel-wide border. It must be saved with the extension  .9.png , and saved into the  res/drawable/  directory of your project. The border is used to define the stretchable and static areas of the image. You indicate a stretchable section ...