18

Android ImageViewでタップ&ピンチズームのようなiPhoneを探していました。 Mike Ortizは、TouchImageView で境界を検出する優れた作業を行いました。彼のコードはここにあります。

このコードには 1 つだけ欠けています。つまり、ダブルタップしてズームします。この機能を Mike Ortiz コードに追加するのを手伝ってくれる人はいますか?

4

6 に答える 6

5

Android の ImageView でピンチ ズームして向きを処理する

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.graphics.Paint;
import android.graphics.PointF;
import android.os.Handler;
import android.util.AttributeSet;
import android.util.FloatMath;
import android.util.Log;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.View;
import android.view.GestureDetector.SimpleOnGestureListener;

public class ZoomableImageView extends View {
    private static final String TAG = "ZoomableImageView";       

    private Bitmap imgBitmap = null;

    private int containerWidth;
    private int containerHeight;

    Paint background;   

    //Matrices will be used to move and zoom image
    Matrix matrix = new Matrix();
    Matrix savedMatrix = new Matrix();

    PointF start = new PointF();       

    float currentScale;
    float curX;
    float curY;

    //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;

    //For animating stuff   
    float targetX;
    float targetY;
    float targetScale;
    float targetScaleX;
    float targetScaleY;
    float scaleChange;
    float targetRatio;
    float transitionalRatio;

    float easing = 0.2f;   
    boolean isAnimating = false;

    float scaleDampingFactor = 0.5f;

    //For pinch and zoom
    float oldDist = 1f;   
    PointF mid = new PointF();

    private Handler mHandler = new Handler();       

    float minScale;
    float maxScale = 8.0f;

    float wpRadius = 25.0f;
    float wpInnerRadius = 20.0f;

    float screenDensity;

    private GestureDetector gestureDetector;

    public static final int DEFAULT_SCALE_FIT_INSIDE = 0;
    public static final int DEFAULT_SCALE_ORIGINAL = 1;

    private int defaultScale;

    public int getDefaultScale() {
        return defaultScale;
    }

    public void setDefaultScale(int defaultScale) {
        this.defaultScale = defaultScale;
    }

    public ZoomableImageView(Context context) {
        super(context);       
        setFocusable(true);
        setFocusableInTouchMode(true);

        screenDensity = context.getResources().getDisplayMetrics().density;

        initPaints();
        gestureDetector = new GestureDetector(new MyGestureDetector());       
    }

    public ZoomableImageView(Context context, AttributeSet attrs) {
        super(context, attrs);

        screenDensity = context.getResources().getDisplayMetrics().density;       
        initPaints();
        gestureDetector = new GestureDetector(new MyGestureDetector());

        defaultScale = ZoomableImageView.DEFAULT_SCALE_FIT_INSIDE;
    }

    private void initPaints() {
        background = new Paint();
    }

    @Override
    protected void onSizeChanged(int width, int height, int oldWidth, int oldHeight) {
        super.onSizeChanged(width, height, oldWidth, oldHeight);

        //Reset the width and height. Will draw bitmap and change
        containerWidth = width;
        containerHeight = height;

        if(imgBitmap != null) {
            int imgHeight = imgBitmap.getHeight();
            int imgWidth = imgBitmap.getWidth();

            float scale;
            int initX = 0;
            int initY = 0;           

            if(defaultScale == ZoomableImageView.DEFAULT_SCALE_FIT_INSIDE) {               
                if(imgWidth > containerWidth) {           
                    scale = (float)containerWidth / imgWidth;           
                    float newHeight = imgHeight * scale;           
                    initY = (containerHeight - (int)newHeight)/2;

                    matrix.setScale(scale, scale);
                    matrix.postTranslate(0, initY);
                }
                else {           
                    scale = (float)containerHeight / imgHeight;
                    float newWidth = imgWidth * scale;
                    initX = (containerWidth - (int)newWidth)/2;

                    matrix.setScale(scale, scale);
                    matrix.postTranslate(initX, 0);
                }

                curX = initX;
                curY = initY;

                currentScale = scale;
                minScale = scale;
            }
            else {
                if(imgWidth > containerWidth) {                                   
                    initY = (containerHeight - (int)imgHeight)/2;                   
                    matrix.postTranslate(0, initY);
                }
                else {                               
                    initX = (containerWidth - (int)imgWidth)/2;                   
                    matrix.postTranslate(initX, 0);
                }

                curX = initX;
                curY = initY;

                currentScale = 1.0f;
                minScale = 1.0f;               
            }


            invalidate();           
        }
    }

    @Override
    protected void onDraw(Canvas canvas) {               
        if(imgBitmap != null && canvas != null)
        {                                           
            canvas.drawBitmap(imgBitmap, matrix, background);                                                   
        }
    }

    //Checks and sets the target image x and y co-ordinates if out of bounds
    private void checkImageConstraints() {
        if(imgBitmap == null) {
            return;
        }

        float[] mvals = new float[9];
        matrix.getValues(mvals);

        currentScale = mvals[0];

        if(currentScale < minScale) {                               
            float deltaScale = minScale / currentScale;                   
            float px = containerWidth/2;
            float py = containerHeight/2;           
            matrix.postScale(deltaScale, deltaScale, px, py);
            invalidate();
        }       

        matrix.getValues(mvals);
        currentScale = mvals[0];
        curX = mvals[2];
        curY = mvals[5];

        int rangeLimitX = containerWidth - (int)(imgBitmap.getWidth() * currentScale);
        int rangeLimitY = containerHeight - (int)(imgBitmap.getHeight() * currentScale);


        boolean toMoveX = false;
        boolean toMoveY = false;   

        if(rangeLimitX < 0) {
            if(curX > 0) {
                targetX = 0;
                toMoveX = true;
            }
            else if(curX < rangeLimitX) {
                targetX = rangeLimitX;
                toMoveX = true;
            }
        }
        else {
            targetX = rangeLimitX / 2;
            toMoveX = true;
        }

        if(rangeLimitY < 0) {
            if(curY > 0) {
                targetY = 0;
                toMoveY = true;
            }
            else if(curY < rangeLimitY) {
                targetY = rangeLimitY;
                toMoveY = true;
            }
        }
        else {
            targetY = rangeLimitY / 2;
            toMoveY = true;
        }

        if(toMoveX == true || toMoveY == true) {
            if(toMoveY == false) {
                targetY = curY;
            }
            if(toMoveX == false) {
                targetX = curX;
            }           

            //Disable touch event actions
            isAnimating = true;
            //Initialize timer           
            mHandler.removeCallbacks(mUpdateImagePositionTask);
            mHandler.postDelayed(mUpdateImagePositionTask, 100);
        }
    }       


    @Override
    public boolean onTouchEvent(MotionEvent event) {       
        if(gestureDetector.onTouchEvent(event)) {
            return true;
        }

        if(isAnimating == true) {
            return true;
        }

        //Handle touch events here       
        float[] mvals = new float[9];
        switch(event.getAction() & MotionEvent.ACTION_MASK) {
        case MotionEvent.ACTION_DOWN:
            if(isAnimating == false) {
                savedMatrix.set(matrix);
                start.set(event.getX(), event.getY());           
                mode = DRAG;               
            }
        break;

        case MotionEvent.ACTION_POINTER_DOWN:
            oldDist = spacing(event);           
            if(oldDist > 10f) {
                savedMatrix.set(matrix);
                midPoint(mid, event);
                mode = ZOOM;
            }
        break;

        case MotionEvent.ACTION_UP:
        case MotionEvent.ACTION_POINTER_UP:
            mode = NONE;

            matrix.getValues(mvals);
            curX = mvals[2];
            curY = mvals[5];
            currentScale = mvals[0];

            if(isAnimating == false) {                                       
                checkImageConstraints();
            }
        break;

        case MotionEvent.ACTION_MOVE:           
            if(mode == DRAG && isAnimating == false) {
                matrix.set(savedMatrix);
                float diffX = event.getX() - start.x;
                float diffY = event.getY() - start.y;

                matrix.postTranslate(diffX, diffY);

                matrix.getValues(mvals);
                curX = mvals[2];
                curY = mvals[5];
                currentScale = mvals[0];
            }
            else if(mode == ZOOM && isAnimating == false) {
                float newDist = spacing(event);               
                if(newDist > 10f) {
                    matrix.set(savedMatrix);
                    float scale = newDist / oldDist;                   
                    matrix.getValues(mvals);
                    currentScale = mvals[0];

                    if(currentScale * scale <= minScale) {
                        matrix.postScale(minScale/currentScale, minScale/currentScale, mid.x, mid.y);
                    }                   
                    else if(currentScale * scale >= maxScale) {
                        matrix.postScale(maxScale/currentScale, maxScale/currentScale, mid.x, mid.y);
                    }
                    else {
                        matrix.postScale(scale, scale, mid.x, mid.y);
                    }


                    matrix.getValues(mvals);
                    curX = mvals[2];
                    curY = mvals[5];
                    currentScale = mvals[0];                                       
                }
            }

        break;                               
        }

        //Calculate the transformations and then invalidate
        invalidate();
        return true;
    }

    private float spacing(MotionEvent event) {
        float x = event.getX(0) - event.getX(1);
        float y = event.getY(0) - event.getY(1);
        return FloatMath.sqrt(x * x + y * y);
    }

    private void midPoint(PointF point, MotionEvent event) {
        float x = event.getX(0) + event.getX(1);
        float y = event.getY(0) + event.getY(1);
        point.set(x/2, y/2);
    }

    public void setImageBitmap(Bitmap b) {       
        if(b != null) {
            imgBitmap = b;               

            containerWidth = getWidth();
            containerHeight = getHeight();

            int imgHeight = imgBitmap.getHeight();
            int imgWidth = imgBitmap.getWidth();

            float scale;
            int initX = 0;
            int initY = 0;

            matrix.reset();

            if(defaultScale == ZoomableImageView.DEFAULT_SCALE_FIT_INSIDE) {               
                if(imgWidth > containerWidth) {           
                    scale = (float)containerWidth / imgWidth;           
                    float newHeight = imgHeight * scale;           
                    initY = (containerHeight - (int)newHeight)/2;

                    matrix.setScale(scale, scale);
                    matrix.postTranslate(0, initY);
                }
                else {           
                    scale = (float)containerHeight / imgHeight;
                    float newWidth = imgWidth * scale;
                    initX = (containerWidth - (int)newWidth)/2;

                    matrix.setScale(scale, scale);
                    matrix.postTranslate(initX, 0);
                }

                curX = initX;
                curY = initY;

                currentScale = scale;
                minScale = scale;
            }
            else {
                if(imgWidth > containerWidth) {
                    initX = 0;
                    if(imgHeight > containerHeight) {                       
                        initY = 0;
                    }
                    else {                       
                        initY = (containerHeight - (int)imgHeight)/2;
                    }

                    matrix.postTranslate(0, initY);
                }
                else {                               
                    initX = (containerWidth - (int)imgWidth)/2;
                    if(imgHeight > containerHeight) {
                        initY = 0;
                    }
                    else {
                        initY = (containerHeight - (int)imgHeight)/2;
                    }
                    matrix.postTranslate(initX, 0);
                }

                curX = initX;
                curY = initY;

                currentScale = 1.0f;
                minScale = 1.0f;               
            }

            invalidate();           
        }
        else {
            Log.d(TAG, "bitmap is null");
        }
    }

    public Bitmap getPhotoBitmap() {       
        return imgBitmap;
    }


    private Runnable mUpdateImagePositionTask = new Runnable() {
        public void run() {       
            float[] mvals;

            if(Math.abs(targetX - curX) < 5 && Math.abs(targetY - curY) < 5) {
                isAnimating = false;
                mHandler.removeCallbacks(mUpdateImagePositionTask);

                mvals = new float[9];
                matrix.getValues(mvals);

                currentScale = mvals[0];
                curX = mvals[2];
                curY = mvals[5];

                //Set the image parameters and invalidate display
                float diffX = (targetX - curX);
                float diffY = (targetY - curY);

                matrix.postTranslate(diffX, diffY);
            }
            else {
                isAnimating = true;
                mvals = new float[9];
                matrix.getValues(mvals);

                currentScale = mvals[0];
                curX = mvals[2];
                curY = mvals[5];

                //Set the image parameters and invalidate display
                float diffX = (targetX - curX) * 0.3f;
                float diffY = (targetY - curY) * 0.3f;

                matrix.postTranslate(diffX, diffY);               
                mHandler.postDelayed(this, 25);               
            }

            invalidate();           
        }
    };

    private Runnable mUpdateImageScale = new Runnable() {
        public void run() {           
            float transitionalRatio = targetScale / currentScale;           
            float dx;
            if(Math.abs(transitionalRatio - 1) > 0.05) {
                isAnimating = true;               
                if(targetScale > currentScale) {                                       
                    dx = transitionalRatio - 1;
                    scaleChange = 1 + dx * 0.2f;

                    currentScale *= scaleChange;

                    if(currentScale > targetScale) {
                        currentScale = currentScale / scaleChange;
                        scaleChange = 1;
                    }
                }
                else {                                   
                    dx = 1 - transitionalRatio;                   
                    scaleChange = 1 - dx * 0.5f;
                    currentScale *= scaleChange;

                    if(currentScale < targetScale) {
                        currentScale = currentScale / scaleChange;
                        scaleChange = 1;
                    }
                }


                if(scaleChange != 1) {
                    matrix.postScale(scaleChange, scaleChange, targetScaleX, targetScaleY);               
                    mHandler.postDelayed(mUpdateImageScale, 15);
                    invalidate();
                }
                else {
                    isAnimating = false;
                    scaleChange = 1;                   
                    matrix.postScale(targetScale/currentScale, targetScale/currentScale, targetScaleX, targetScaleY);
                    currentScale = targetScale;
                    mHandler.removeCallbacks(mUpdateImageScale);
                    invalidate();
                    checkImageConstraints();
                }               
            }
            else {
                isAnimating = false;
                scaleChange = 1;               
                matrix.postScale(targetScale/currentScale, targetScale/currentScale, targetScaleX, targetScaleY);
                currentScale = targetScale;
                mHandler.removeCallbacks(mUpdateImageScale);
                invalidate();
                checkImageConstraints();
            }                               
        }
    };

   /** Show an event in the LogCat view, for debugging */
   private void dumpEvent(MotionEvent event) {
      String names[] = { "DOWN", "UP", "MOVE", "CANCEL", "OUTSIDE", "POINTER_DOWN", "POINTER_UP", "7?", "8?", "9?" };
      StringBuilder sb = new StringBuilder();
      int action = event.getAction();
      int actionCode = action & MotionEvent.ACTION_MASK;
      sb.append("event ACTION_").append(names[actionCode]);
      if (actionCode == MotionEvent.ACTION_POINTER_DOWN || actionCode == MotionEvent.ACTION_POINTER_UP) {
         sb.append("(pid ").append(action >> MotionEvent.ACTION_POINTER_ID_SHIFT);
         sb.append(")");
      }
      sb.append("[");

      for (int i = 0; i < event.getPointerCount(); i++) {
         sb.append("#").append(i);
         sb.append("(pid ").append(event.getPointerId(i));
         sb.append(")=").append((int) event.getX(i));
         sb.append(",").append((int) event.getY(i));
         if (i + 1 < event.getPointerCount())
            sb.append(";");
      }
      sb.append("]");
   }

   class MyGestureDetector extends SimpleOnGestureListener {
        @Override
        public boolean onDoubleTap(MotionEvent event) {           
            if(isAnimating == true) {
                return true;
            }

            scaleChange = 1;
            isAnimating = true;
            targetScaleX = event.getX();
            targetScaleY = event.getY();

            if(Math.abs(currentScale - maxScale) > 0.1) {           
                targetScale = maxScale;
            }
            else {
                targetScale = minScale;
            }
            targetRatio = targetScale / currentScale;
            mHandler.removeCallbacks(mUpdateImageScale);
            mHandler.post(mUpdateImageScale);           
            return true;
        }

        @Override
        public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX, float velocityY) {
            return super.onFling(e1, e2, velocityX, velocityY);
        }

        @Override
        public boolean onDown(MotionEvent e) {
            return false;
        }
    }
}
于 2013-09-17T08:21:24.563 に答える
3

ここでは、ピンチによるズームとダブルタップによるズームの両方で機能します。

import android.annotation.TargetApi;
import android.content.Context;
import android.content.res.Configuration;
import android.graphics.*;
import android.graphics.drawable.Drawable;
import android.net.Uri;
import android.os.Build.VERSION;
import android.os.Build.VERSION_CODES;
import android.os.Bundle;
import android.os.Parcelable;
import android.util.AttributeSet;
import android.util.Log;
import android.view.GestureDetector;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.View;
import android.view.animation.AccelerateDecelerateInterpolator;
import android.widget.OverScroller;
import android.widget.Scroller;
import androidx.appcompat.widget.AppCompatImageView;

public class TouchImageView extends AppCompatImageView {

    private static final String DEBUG = "DEBUG";

    //
    // SuperMin and SuperMax multipliers. Determine how much the image can be
    // zoomed below or above the zoom boundaries, before animating back to the
    // min/max zoom boundary.
    //
    private static final float SUPER_MIN_MULTIPLIER = .75f;
    private static final float SUPER_MAX_MULTIPLIER = 1.25f;

    //
    // Scale of image ranges from minScale to maxScale, where minScale == 1
    // when the image is stretched to fit view.
    //
    private float normalizedScale;

    //
    // Matrix applied to image. MSCALE_X and MSCALE_Y should always be equal.
    // MTRANS_X and MTRANS_Y are the other values used. prevMatrix is the matrix
    // saved prior to the screen rotating.
    //
    private Matrix matrix, prevMatrix;

    private static enum State {NONE, DRAG, ZOOM, FLING, ANIMATE_ZOOM}

    ;
    private State state;

    private float minScale;
    private float maxScale;
    private float superMinScale;
    private float superMaxScale;
    private float[] m;

    private Context context;
    private Fling fling;

    private ScaleType mScaleType;

    private boolean imageRenderedAtLeastOnce;
    private boolean onDrawReady;

    private ZoomVariables delayedZoomVariables;

    //
    // Size of view and previous view size (ie before rotation)
    //
    private int viewWidth, viewHeight, prevViewWidth, prevViewHeight;

    //
    // Size of image when it is stretched to fit view. Before and After rotation.
    //
    private float matchViewWidth, matchViewHeight, prevMatchViewWidth, prevMatchViewHeight;

    private ScaleGestureDetector mScaleDetector;
    private GestureDetector mGestureDetector;
    private GestureDetector.OnDoubleTapListener doubleTapListener = null;
    private OnTouchListener userTouchListener = null;
    private OnTouchImageViewListener touchImageViewListener = null;

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

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

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

    private void sharedConstructing(Context context) {
        super.setClickable(true);
        this.context = context;
        mScaleDetector = new ScaleGestureDetector(context, new ScaleListener());
        mGestureDetector = new GestureDetector(context, new GestureListener());
        matrix = new Matrix();
        prevMatrix = new Matrix();
        m = new float[9];
        normalizedScale = 1;
        if (mScaleType == null) {
            mScaleType = ScaleType.FIT_CENTER;
        }
        minScale = 1;
        maxScale = 3;
        superMinScale = SUPER_MIN_MULTIPLIER * minScale;
        superMaxScale = SUPER_MAX_MULTIPLIER * maxScale;
        setImageMatrix(matrix);
        setScaleType(ScaleType.MATRIX);
        setState(State.NONE);
        onDrawReady = false;
        super.setOnTouchListener(new PrivateOnTouchListener());
    }

    @Override
    public void setOnTouchListener(OnTouchListener l) {
        userTouchListener = l;
    }

    public void setOnTouchImageViewListener(OnTouchImageViewListener l) {
        touchImageViewListener = l;
    }

    public void setOnDoubleTapListener(GestureDetector.OnDoubleTapListener l) {
        doubleTapListener = l;
    }

    @Override
    public void setImageResource(int resId) {
        super.setImageResource(resId);
        savePreviousImageValues();
        fitImageToView();
    }

    @Override
    public void setImageBitmap(Bitmap bm) {
        super.setImageBitmap(bm);
        savePreviousImageValues();
        fitImageToView();
    }

    @Override
    public void setImageDrawable(Drawable drawable) {
        super.setImageDrawable(drawable);
        savePreviousImageValues();
        fitImageToView();
    }

    @Override
    public void setImageURI(Uri uri) {
        super.setImageURI(uri);
        savePreviousImageValues();
        fitImageToView();
    }

    @Override
    public void setScaleType(ScaleType type) {
        if (type == ScaleType.FIT_START || type == ScaleType.FIT_END) {
            throw new UnsupportedOperationException("TouchImageView does not support FIT_START or FIT_END");
        }
        if (type == ScaleType.MATRIX) {
            super.setScaleType(ScaleType.MATRIX);

        } else {
            mScaleType = type;
            if (onDrawReady) {
                //
                // If the image is already rendered, scaleType has been called programmatically
                // and the TouchImageView should be updated with the new scaleType.
                //
                setZoom(this);
            }
        }
    }

    @Override
    public ScaleType getScaleType() {
        return mScaleType;
    }

    /**
     * Returns false if image is in initial, unzoomed state. False, otherwise.
     *
     * @return true if image is zoomed
     */
    public boolean isZoomed() {
        return normalizedScale != 1;
    }

    /**
     * Return a Rect representing the zoomed image.
     *
     * @return rect representing zoomed image
     */
    public RectF getZoomedRect() {
        if (mScaleType == ScaleType.FIT_XY) {
            throw new UnsupportedOperationException("getZoomedRect() not supported with FIT_XY");
        }
        PointF topLeft = transformCoordTouchToBitmap(0, 0, true);
        PointF bottomRight = transformCoordTouchToBitmap(viewWidth, viewHeight, true);

        float w = getDrawable().getIntrinsicWidth();
        float h = getDrawable().getIntrinsicHeight();
        return new RectF(topLeft.x / w, topLeft.y / h, bottomRight.x / w, bottomRight.y / h);
    }

    /**
     * Save the current matrix and view dimensions
     * in the prevMatrix and prevView variables.
     */
    private void savePreviousImageValues() {
        if (matrix != null && viewHeight != 0 && viewWidth != 0) {
            matrix.getValues(m);
            prevMatrix.setValues(m);
            prevMatchViewHeight = matchViewHeight;
            prevMatchViewWidth = matchViewWidth;
            prevViewHeight = viewHeight;
            prevViewWidth = viewWidth;
        }
    }

    @Override
    public Parcelable onSaveInstanceState() {
        Bundle bundle = new Bundle();
        bundle.putParcelable("instanceState", super.onSaveInstanceState());
        bundle.putFloat("saveScale", normalizedScale);
        bundle.putFloat("matchViewHeight", matchViewHeight);
        bundle.putFloat("matchViewWidth", matchViewWidth);
        bundle.putInt("viewWidth", viewWidth);
        bundle.putInt("viewHeight", viewHeight);
        matrix.getValues(m);
        bundle.putFloatArray("matrix", m);
        bundle.putBoolean("imageRendered", imageRenderedAtLeastOnce);
        return bundle;
    }

    @Override
    public void onRestoreInstanceState(Parcelable state) {
        if (state instanceof Bundle) {
            Bundle bundle = (Bundle) state;
            normalizedScale = bundle.getFloat("saveScale");
            m = bundle.getFloatArray("matrix");
            prevMatrix.setValues(m);
            prevMatchViewHeight = bundle.getFloat("matchViewHeight");
            prevMatchViewWidth = bundle.getFloat("matchViewWidth");
            prevViewHeight = bundle.getInt("viewHeight");
            prevViewWidth = bundle.getInt("viewWidth");
            imageRenderedAtLeastOnce = bundle.getBoolean("imageRendered");
            super.onRestoreInstanceState(bundle.getParcelable("instanceState"));
            return;
        }

        super.onRestoreInstanceState(state);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        onDrawReady = true;
        imageRenderedAtLeastOnce = true;
        if (delayedZoomVariables != null) {
            setZoom(delayedZoomVariables.scale, delayedZoomVariables.focusX, delayedZoomVariables.focusY, delayedZoomVariables.scaleType);
            delayedZoomVariables = null;
        }
        super.onDraw(canvas);
    }

    @Override
    public void onConfigurationChanged(Configuration newConfig) {
        super.onConfigurationChanged(newConfig);
        savePreviousImageValues();
    }

    /**
     * Get the max zoom multiplier.
     *
     * @return max zoom multiplier.
     */
    public float getMaxZoom() {
        return maxScale;
    }

    /**
     * Set the max zoom multiplier. Default value: 3.
     *
     * @param max max zoom multiplier.
     */
    public void setMaxZoom(float max) {
        maxScale = max;
        superMaxScale = SUPER_MAX_MULTIPLIER * maxScale;
    }

    /**
     * Get the min zoom multiplier.
     *
     * @return min zoom multiplier.
     */
    public float getMinZoom() {
        return minScale;
    }

    /**
     * Get the current zoom. This is the zoom relative to the initial
     * scale, not the original resource.
     *
     * @return current zoom multiplier.
     */
    public float getCurrentZoom() {
        return normalizedScale;
    }

    /**
     * Set the min zoom multiplier. Default value: 1.
     *
     * @param min min zoom multiplier.
     */
    public void setMinZoom(float min) {
        minScale = min;
        superMinScale = SUPER_MIN_MULTIPLIER * minScale;
    }

    /**
     * Reset zoom and translation to initial state.
     */
    public void resetZoom() {
        normalizedScale = 1;
        fitImageToView();
    }

    /**
     * Set zoom to the specified scale. Image will be centered by default.
     *
     * @param scale
     */
    public void setZoom(float scale) {
        setZoom(scale, 0.5f, 0.5f);
    }

    /**
     * Set zoom to the specified scale. Image will be centered around the point
     * (focusX, focusY). These floats range from 0 to 1 and denote the focus point
     * as a fraction from the left and top of the view. For example, the top left
     * corner of the image would be (0, 0). And the bottom right corner would be (1, 1).
     *
     * @param scale
     * @param focusX
     * @param focusY
     */
    public void setZoom(float scale, float focusX, float focusY) {
        setZoom(scale, focusX, focusY, mScaleType);
    }

    /**
     * Set zoom to the specified scale. Image will be centered around the point
     * (focusX, focusY). These floats range from 0 to 1 and denote the focus point
     * as a fraction from the left and top of the view. For example, the top left
     * corner of the image would be (0, 0). And the bottom right corner would be (1, 1).
     *
     * @param scale
     * @param focusX
     * @param focusY
     * @param scaleType
     */
    public void setZoom(float scale, float focusX, float focusY, ScaleType scaleType) {
        //
        // setZoom can be called before the image is on the screen, but at this point,
        // image and view sizes have not yet been calculated in onMeasure. Thus, we should
        // delay calling setZoom until the view has been measured.
        //
        if (!onDrawReady) {
            delayedZoomVariables = new ZoomVariables(scale, focusX, focusY, scaleType);
            return;
        }

        if (scaleType != mScaleType) {
            setScaleType(scaleType);
        }
        resetZoom();
        scaleImage(scale, viewWidth / 2, viewHeight / 2, true);
        matrix.getValues(m);
        m[Matrix.MTRANS_X] = -((focusX * getImageWidth()) - (viewWidth * 0.5f));
        m[Matrix.MTRANS_Y] = -((focusY * getImageHeight()) - (viewHeight * 0.5f));
        matrix.setValues(m);
        fixTrans();
        setImageMatrix(matrix);
    }

    /**
     * Set zoom parameters equal to another TouchImageView. Including scale, position,
     * and ScaleType.
     *
     * @param
     */
    public void setZoom(TouchImageView img) {
        PointF center = img.getScrollPosition();
        setZoom(img.getCurrentZoom(), center.x, center.y, img.getScaleType());
    }

    /**
     * Return the point at the center of the zoomed image. The PointF coordinates range
     * in value between 0 and 1 and the focus point is denoted as a fraction from the left
     * and top of the view. For example, the top left corner of the image would be (0, 0).
     * And the bottom right corner would be (1, 1).
     *
     * @return PointF representing the scroll position of the zoomed image.
     */
    public PointF getScrollPosition() {
        Drawable drawable = getDrawable();
        if (drawable == null) {
            return null;
        }
        int drawableWidth = drawable.getIntrinsicWidth();
        int drawableHeight = drawable.getIntrinsicHeight();

        PointF point = transformCoordTouchToBitmap(viewWidth / 2, viewHeight / 2, true);
        point.x /= drawableWidth;
        point.y /= drawableHeight;
        return point;
    }

    /**
     * Set the focus point of the zoomed image. The focus points are denoted as a fraction from the
     * left and top of the view. The focus points can range in value between 0 and 1.
     *
     * @param focusX
     * @param focusY
     */
    public void setScrollPosition(float focusX, float focusY) {
        setZoom(normalizedScale, focusX, focusY);
    }

    /**
     * Performs boundary checking and fixes the image matrix if it
     * is out of bounds.
     */
    private void fixTrans() {
        matrix.getValues(m);
        float transX = m[Matrix.MTRANS_X];
        float transY = m[Matrix.MTRANS_Y];

        float fixTransX = getFixTrans(transX, viewWidth, getImageWidth());
        float fixTransY = getFixTrans(transY, viewHeight, getImageHeight());

        if (fixTransX != 0 || fixTransY != 0) {
            matrix.postTranslate(fixTransX, fixTransY);
        }
    }

    /**
     * When transitioning from zooming from focus to zoom from center (or vice versa)
     * the image can become unaligned within the view. This is apparent when zooming
     * quickly. When the content size is less than the view size, the content will often
     * be centered incorrectly within the view. fixScaleTrans first calls fixTrans() and
     * then makes sure the image is centered correctly within the view.
     */
    private void fixScaleTrans() {
        fixTrans();
        matrix.getValues(m);
        if (getImageWidth() < viewWidth) {
            m[Matrix.MTRANS_X] = (viewWidth - getImageWidth()) / 2;
        }

        if (getImageHeight() < viewHeight) {
            m[Matrix.MTRANS_Y] = (viewHeight - getImageHeight()) / 2;
        }
        matrix.setValues(m);
    }

    private 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;
    }

    private float getFixDragTrans(float delta, float viewSize, float contentSize) {
        if (contentSize <= viewSize) {
            return 0;
        }
        return delta;
    }

    private float getImageWidth() {
        return matchViewWidth * normalizedScale;
    }

    private float getImageHeight() {
        return matchViewHeight * normalizedScale;
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        Drawable drawable = getDrawable();
        if (drawable == null || drawable.getIntrinsicWidth() == 0 || drawable.getIntrinsicHeight() == 0) {
            setMeasuredDimension(0, 0);
            return;
        }

        int drawableWidth = drawable.getIntrinsicWidth();
        int drawableHeight = drawable.getIntrinsicHeight();
        int widthSize = MeasureSpec.getSize(widthMeasureSpec);
        int widthMode = MeasureSpec.getMode(widthMeasureSpec);
        int heightSize = MeasureSpec.getSize(heightMeasureSpec);
        int heightMode = MeasureSpec.getMode(heightMeasureSpec);
        viewWidth = setViewSize(widthMode, widthSize, drawableWidth);
        viewHeight = setViewSize(heightMode, heightSize, drawableHeight);

        //
        // Set view dimensions
        //
        setMeasuredDimension(viewWidth, viewHeight);

        //
        // Fit content within view
        //
        fitImageToView();
    }

    /**
     * If the normalizedScale is equal to 1, then the image is made to fit the screen. Otherwise,
     * it is made to fit the screen according to the dimensions of the previous image matrix. This
     * allows the image to maintain its zoom after rotation.
     */
    private void fitImageToView() {
        Drawable drawable = getDrawable();
        if (drawable == null || drawable.getIntrinsicWidth() == 0 || drawable.getIntrinsicHeight() == 0) {
            return;
        }
        if (matrix == null || prevMatrix == null) {
            return;
        }

        int drawableWidth = drawable.getIntrinsicWidth();
        int drawableHeight = drawable.getIntrinsicHeight();

        //
        // Scale image for view
        //
        float scaleX = (float) viewWidth / drawableWidth;
        float scaleY = (float) viewHeight / drawableHeight;

        switch (mScaleType) {
            case CENTER:
                scaleX = scaleY = 1;
                break;

            case CENTER_CROP:
                scaleX = scaleY = Math.max(scaleX, scaleY);
                break;

            case CENTER_INSIDE:
                scaleX = scaleY = Math.min(1, Math.min(scaleX, scaleY));

            case FIT_CENTER:
                scaleX = scaleY = Math.min(scaleX, scaleY);
                break;

            case FIT_XY:
                break;

            default:
                //
                // FIT_START and FIT_END not supported
                //
                throw new UnsupportedOperationException("TouchImageView does not support FIT_START or FIT_END");

        }

        //
        // Center the image
        //
        float redundantXSpace = viewWidth - (scaleX * drawableWidth);
        float redundantYSpace = viewHeight - (scaleY * drawableHeight);
        matchViewWidth = viewWidth - redundantXSpace;
        matchViewHeight = viewHeight - redundantYSpace;
        if (!isZoomed() && !imageRenderedAtLeastOnce) {
            //
            // Stretch and center image to fit view
            //
            matrix.setScale(scaleX, scaleY);
            matrix.postTranslate(redundantXSpace / 2, redundantYSpace / 2);
            normalizedScale = 1;

        } else {
            //
            // These values should never be 0 or we will set viewWidth and viewHeight
            // to NaN in translateMatrixAfterRotate. To avoid this, call savePreviousImageValues
            // to set them equal to the current values.
            //
            if (prevMatchViewWidth == 0 || prevMatchViewHeight == 0) {
                savePreviousImageValues();
            }

            prevMatrix.getValues(m);

            //
            // Rescale Matrix after rotation
            //
            m[Matrix.MSCALE_X] = matchViewWidth / drawableWidth * normalizedScale;
            m[Matrix.MSCALE_Y] = matchViewHeight / drawableHeight * normalizedScale;

            //
            // TransX and TransY from previous matrix
            //
            float transX = m[Matrix.MTRANS_X];
            float transY = m[Matrix.MTRANS_Y];

            //
            // Width
            //
            float prevActualWidth = prevMatchViewWidth * normalizedScale;
            float actualWidth = getImageWidth();
            translateMatrixAfterRotate(Matrix.MTRANS_X, transX, prevActualWidth, actualWidth, prevViewWidth, viewWidth, drawableWidth);

            //
            // Height
            //
            float prevActualHeight = prevMatchViewHeight * normalizedScale;
            float actualHeight = getImageHeight();
            translateMatrixAfterRotate(Matrix.MTRANS_Y, transY, prevActualHeight, actualHeight, prevViewHeight, viewHeight, drawableHeight);

            //
            // Set the matrix to the adjusted scale and translate values.
            //
            matrix.setValues(m);
        }
        fixTrans();
        setImageMatrix(matrix);
    }

    /**
     * Set view dimensions based on layout params
     *
     * @param mode
     * @param size
     * @param drawableWidth
     * @return
     */
    private int setViewSize(int mode, int size, int drawableWidth) {
        int viewSize;
        switch (mode) {
            case MeasureSpec.EXACTLY:
                viewSize = size;
                break;

            case MeasureSpec.AT_MOST:
                viewSize = Math.min(drawableWidth, size);
                break;

            case MeasureSpec.UNSPECIFIED:
                viewSize = drawableWidth;
                break;

            default:
                viewSize = size;
                break;
        }
        return viewSize;
    }


    ........

参照: https://gist.github.com/myinnos/e14b750be9503a2b2611f5a5a74a9e6c

SOF は 30000 文字に制限されているため、コードの最後の行を見落とす可能性があります。上記のリンクからクラスを受講してください。

次のように XML で使用します。

<com.mypackagename.TouchImageView
            android:id="@+id/productImage"
            android:layout_width="match_parent"
            android:layout_height="match_parent"
            android:scaleType="fitCenter"/>
于 2019-01-13T18:58:24.613 に答える
-1

シングルタップ リスナーによるズーム可能なイメージビュー

import android.content.Context;
import android.graphics.Rect;
import android.graphics.RectF;
import android.util.AttributeSet;
import android.view.MotionEvent;
import android.view.View;

import it.sephiroth.android.library.imagezoom.ImageViewTouch;

public class MyZoomableImageViewTouch extends ImageViewTouch
{

    static final float SCROLL_DELTA_THRESHOLD = 1.0f;

    public MyZoomableImageViewTouch(Context context, AttributeSet attrs, int defStyle)
    {
        super(context, attrs, defStyle);
        init();
    }

    public MyZoomableImageViewTouch(Context context, AttributeSet attrs) {
         super(context, attrs);
         init();
    }

    public MyZoomableImageViewTouch(Context context)
    {
        super(context);
        init();
    }

    private void init() {
        View.OnTouchListener listener = new View.OnTouchListener() {
            @Override
            public boolean onTouch(View v, MotionEvent event) {
                 if (getScale() > 1f) {
                 getParent().requestDisallowInterceptTouchEvent(true);
                 } else {
                 getParent().requestDisallowInterceptTouchEvent(false);
                 }
                 return false;
            }
           };
           setOnTouchListener(listener);
           setDisplayType(DisplayType.FIT_TO_SCREEN);
     }

     @Override
    protected float onDoubleTapPost(float scale, float maxZoom) {
        if (scale != 1f) {
           mDoubleTapDirection = 1;
           return 1f;
       }
       if (mDoubleTapDirection == 1) {
            mDoubleTapDirection = -1;
          if ((scale + (mScaleFactor * 2)) <= maxZoom) {
              return scale + mScaleFactor;
          }   else {
              mDoubleTapDirection = -1;
              return maxZoom;
          }
        } else {
          mDoubleTapDirection = 1;
          return 1f;
       }
  }

    @Override
    public boolean canScroll(int direction) {
       RectF bitmapRect = getBitmapRect();
       updateRect(bitmapRect, mScrollRect);
       Rect imageViewRect = new Rect();
       getGlobalVisibleRect(imageViewRect);

       if (null == bitmapRect) {
          return false;
       }

       if (Math.abs(bitmapRect.right - imageViewRect.right) < SCROLL_DELTA_THRESHOLD) {
           if (direction < 0) {
                return false;
           }
       }

       if (Math.abs(bitmapRect.left - mScrollRect.left) <  SCROLL_DELTA_THRESHOLD) {
           if (direction > 0) {
               return false;
           }
       }
       return true;
   }

   @Override
   public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY)
   {
        if (getScale() == 1f) return false;
        if (distanceX != 0 && !canScroll((int) -distanceX)) {
             getParent().requestDisallowInterceptTouchEvent(false);
             return false;
        } else {
             getParent().requestDisallowInterceptTouchEvent(true);
             mUserScaled = true;
             scrollBy(-distanceX, -distanceY);
            invalidate();
            return true;
       }
   }
}

シングルタップにはこの方法を使用します

    imageView.setSingleTapListener(new ImageViewTouch.OnImageViewTouchSingleTapListener()
    {
        @Override
        public void onSingleTapConfirmed()
        {
        }
     }
于 2017-03-24T12:05:47.537 に答える