Question

我正在制作应用，其中图像可以放大和缩小，所以我使用矩阵比例类型但有些图像不适合屏幕（不能使用scaletype fit xy）。如何在不改变缩放比例的情况下将图像适合全屏

   import android.annotation.SuppressLint;
   import android.app.Activity;
   import android.graphics.Matrix;
   import android.graphics.PointF;
   import android.os.Bundle;
   import android.util.FloatMath;
   import android.view.MotionEvent;
   import android.view.View;
   import android.widget.ImageView;
   import android.widget.ImageView.ScaleType;
   import android.widget.RelativeLayout;
   public class MainActivity extends Activity {
    ImageView imageDetail;
    Matrix matrix = new Matrix();
    Matrix savedMatrix = new Matrix();
    PointF startPoint = new PointF();
    PointF midPoint = new PointF();
    public RelativeLayout myL;

    float oldDist = 1f;
    static final int NONE = 0;
    static final int DRAG = 1;
    static final int ZOOM = 2;
    int mode = NONE;
    /** Called when the activity is first created. */
    @Override public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.activity_main);
            imageDetail = (ImageView) findViewById(R.id.imageView1);
            imageDetail.setScaleType(ScaleType.FIT_XY);
            /** * set on touch listner on image */
    imageDetail.setOnTouchListener(new View.OnTouchListener()
    { @Override public boolean onTouch(View v, MotionEvent event) {
        //imageDetail.setScaleType(ScaleType.MATRIX);
        ImageView view = (ImageView) v;
        System.out.println("matrix=" + savedMatrix.toString());
        switch (event.getAction() & MotionEvent.ACTION_MASK) {
        case MotionEvent.ACTION_DOWN: savedMatrix.set(matrix);
        startPoint.set(event.getX(), event.getY());
        mode = DRAG;
        break;
        case MotionEvent.ACTION_POINTER_DOWN:
            oldDist = spacing(event);
        if (oldDist > 10f) {
            savedMatrix.set(matrix);
            midPoint(midPoint, event);
            mode = ZOOM;
            } 
        break;
        case MotionEvent.ACTION_UP:
            case MotionEvent.ACTION_POINTER_UP:
                mode = NONE;
                break;
                case MotionEvent.ACTION_MOVE:

                     if (mode == ZOOM) {
                        float newDist = spacing(event);
            if (newDist > 10f) {
            matrix.set(savedMatrix);
            float scale = newDist / oldDist;                          
            matrix.postScale(scale,    scale, midPoint.x, midPoint.y);
            }
                        }
                    break;
                    }
        view.setImageMatrix(matrix); return true;
        }
    @SuppressLint
    ("FloatMath") 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);
        } });
    }
}

这是XML

 <RelativeLayout
      xmlns:android="http://schemas.android.com/apk/res/android"
      xmlns:tools="http://schemas.android.com/tools"
      android:layout_width="match_parent" 
      android:layout_height="match_parent" >

     <ImageView
           android:id="@+id/imageView1"
           android:layout_width="fill_parent"
           android:layout_height="fill_parent"
           android:scaleType="matrix"
           android:src="@drawable/k13"
            />
    </RelativeLayout>

使imageView适合屏幕而不更改scaletype属性

0 个答案: