如何通過點擊一個圖像到全屏和縮放顯示？

Question

我見過很多關於這個問題的答案。但是這些都不適合我。我只是想知道如何通過點擊/觸摸到全屏視圖來顯示和immageview縮略圖，並且它可以放大縮小。

謝謝

Answer 1

而不是使用ImageView類TouchImageView，足額 屏幕

public class TouchImageView extends ImageView { 

    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(ScaleType.MATRIX); 

     setOnTouchListener(new 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 = MeasureSpec.getSize(widthMeasureSpec); 
     viewHeight = 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(); 
    } 
}