java - 可点击图片

Question

我正在尝试在我的 android 应用程序中编写一个可使用以下代码重新缩放的图像

    package million.tyler;

    import android.content.Intent;
    import android.graphics.Matrix;
    import android.graphics.PointF;
    import android.net.Uri;
    import android.util.FloatMath;
    import android.view.MotionEvent;
    import android.view.View;
    import android.view.View.OnTouchListener;
    import android.widget.ImageView;
    import android.widget.Toast;

    public class Touch implements OnTouchListener {

     // These matrices will be used to move and zoom image
     Matrix matrix = new Matrix();
     Matrix savedMatrix = new 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 start = new PointF();
     PointF mid = new PointF();
     float oldDist = 1f;


     @Override
     public boolean onTouch(View v, MotionEvent event) {
      ImageView view = (ImageView) v;
      // Dump touch event to log
      dumpEvent(event);

      // Handle touch events here...
      switch (event.getAction() & MotionEvent.ACTION_MASK) {
      case MotionEvent.ACTION_DOWN:
       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;
       break;
      case MotionEvent.ACTION_MOVE:
       if (mode == DRAG) {
                // ...    
        matrix.set(savedMatrix);
        matrix.postTranslate(event.getX() - start.x, event.getY() - start.y);    
       } else if (mode == ZOOM) {
        float newDist = spacing(event);
        if (newDist > 10f) {
         matrix.set(savedMatrix);
         float scale = newDist / oldDist;
         matrix.postScale(scale, scale, mid.x, mid.y);
        }
       }
       break;
      }

      view.setImageMatrix(matrix);
      return true; // indicate event was handled
     }

     /** 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("]");
     }

     /** Determine the space between the first two fingers */
     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);
     }

     /** Calculate the mid point of the first two fingers */
     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);
     }

除此之外，我还希望图片在不同地区都可以点击。有点像 html 中的图像映射。我是编码新手，因此非常感谢您的帮助。

Answer 1

这可以通过指定图像的特定坐标来实现，就像用户点击(0,0 到 100,100)触发某个事件一样。

或者还有另一种做事方式。您可以使用 webview 而不是 imageview 来加载图像。您可以简单地为图像制作 HTML map ，然后可以执行不同的功能。此外，您还可以在您的 android 代码中获取 javascript 事件... 更多的自己去探索...:P