無法放大巴士路線圖

Question

我有巴士路線圖作爲圖像。 使用變焦控制器將圖像縮小，但在 沒有放大請看看我的代碼，讓我知道做的改變使得它的工作.. 我正在開發的薑餅即，API我的應用程序10

import android.os.Bundle; 
import android.app.Activity; 
import android.view.Menu; 
import android.view.View; 
import android.widget.ImageView; 
import android.widget.RelativeLayout; 
import android.widget.ZoomControls; 

public class Busmaps extends Activity { 

ImageView img; 
ZoomControls zoom; 

@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.busmaps); 

    img = (ImageView) findViewById(R.id.imageViewmaps1); 
    zoom = (ZoomControls) findViewById(R.id.zoomControls1); 

    zoom.setOnZoomInClickListener(new View.OnClickListener() { 

    @Override 
    public void onClick(View v) { 
     // TODO Auto-generated method stub 

     int w = img.getWidth(); 
     int h = img.getHeight(); 

     RelativeLayout.LayoutParams params = 
      new RelativeLayout.LayoutParams(w + 50, h + 50); 
     params.addRule(RelativeLayout.CENTER_IN_PARENT); 

     img.setLayoutParams(params); 
    } 
    }); 

     zoom.setOnZoomOutClickListener(new View.OnClickListener() { 

    @Override 
    public void onClick(View v) { 
     // TODO Auto-generated method stub 

     int w = img.getWidth(); 
     int h = img.getHeight(); 

     RelativeLayout.LayoutParams params = 
      new RelativeLayout.LayoutParams(w - 50, h - 50); 
     params.addRule(RelativeLayout.CENTER_IN_PARENT); 

     img.setLayoutParams(params); 
    } 
    }); 
    } 

    @Override 
    public boolean onCreateOptionsMenu(Menu menu) { 
    getMenuInflater().inflate(R.menu.bus_map_zoom, menu); 
    return true; 
    } 
    } 

我的XML說，對公交路線圖像： -

<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/imageViewmaps1" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:layout_centerHorizontal="true" 
    android:layout_centerVertical="true" 
    android:src="@drawable/map" /> 

    <ZoomControls 
    android:id="@+id/zoomControls1" 
    android:layout_width="wrap_content" 
    android:layout_height="wrap_content" 
    android:layout_alignParentBottom="true" 
    android:layout_centerHorizontal="true" 
    /> 

    </RelativeLayout> 

我應該如何讓我的變焦控制工作都放大和縮小。

Answer 1

public class Busmap extends Activity implements OnTouchListener 
{ 
private static final String TAG = "Touch"; 
@SuppressWarnings("unused") 
private static final float MIN_ZOOM = 1f,MAX_ZOOM = 1f; 

// These matrices will be used to scale points of the image 
Matrix matrix = new Matrix(); 
Matrix savedMatrix = new Matrix(); 

// The 3 states (events) which the user is trying to perform 
static final int NONE = 0; 
static final int DRAG = 1; 
static final int ZOOM = 2; 
int mode = NONE; 

// these PointF objects are used to record the point(s) the user is touching 
PointF start = new PointF(); 
PointF mid = new PointF(); 
float oldDist = 1f; 

/** Called when the activity is first created. */ 
@Override 
public void onCreate(Bundle savedInstanceState) 
{ 
    super.onCreate(savedInstanceState); 
    setContentView(R.layout.busmaps); 
    ImageView view = (ImageView) findViewById(R.id.imageViewmaps1); 
    view.setOnTouchListener(this); 
} 

@Override 
public boolean onTouch(View v, MotionEvent event) 
{ 
    ImageView view = (ImageView) v; 
    view.setScaleType(ImageView.ScaleType.MATRIX); 
    float scale; 

    dumpEvent(event); 
    // Handle touch events here... 

    switch (event.getAction() & MotionEvent.ACTION_MASK) 
    { 
     case MotionEvent.ACTION_DOWN: // first finger down only 
              savedMatrix.set(matrix); 
              start.set(event.getX(), event.getY()); 
              Log.d(TAG, "mode=DRAG"); // write to LogCat 
              mode = DRAG; 
              break; 

     case MotionEvent.ACTION_UP: // first finger lifted 

     case MotionEvent.ACTION_POINTER_UP: // second finger lifted 

              mode = NONE; 
              Log.d(TAG, "mode=NONE"); 
              break; 

     case MotionEvent.ACTION_POINTER_DOWN: // first and second finger down 

              oldDist = spacing(event); 
              Log.d(TAG, "oldDist=" + oldDist); 
              if (oldDist > 5f) { 
               savedMatrix.set(matrix); 
               midPoint(mid, event); 
               mode = ZOOM; 
               Log.d(TAG, "mode=ZOOM"); 
              } 
              break; 

     case MotionEvent.ACTION_MOVE: 

              if (mode == DRAG) 
              { 
               matrix.set(savedMatrix); 
               matrix.postTranslate(event.getX() - start.x, event.getY() - start.y); // create the transformation in the matrix of points 
              } 
              else if (mode == ZOOM) 
              { 
               // pinch zooming 
               float newDist = spacing(event); 
               Log.d(TAG, "newDist=" + newDist); 
               if (newDist > 5f) 
               { 
                matrix.set(savedMatrix); 
                scale = newDist/oldDist; // setting the scaling of the 
                       // matrix...if scale > 1 means 
                       // zoom in...if scale < 1 means 
                       // zoom out 
                matrix.postScale(scale, scale, mid.x, mid.y); 
               } 
              } 
              break; 
    } 

    view.setImageMatrix(matrix); // display the transformation on screen 

    return true; // indicate event was handled 
} 



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); 
} 

Answer 2

請用以下內容替換您的放大和縮小（ZoomOut）聽衆：

zoom.setOnZoomInClickListener(new OnClickListener() { 

    @Override 
    public void onClick(View v) { 
     // TODO Auto-generated method stub 

     float x = img.getScaleX(); 
     float y = img.getScaleY(); 

     img.setScaleX((float) (x+1)); 
     img.setScaleY((float) (y+1)); 
    } 
}); 

    zoom.setOnZoomOutClickListener(new View.OnClickListener() { 

    @Override 
    public void onClick(View v) { 
     // TODO Auto-generated method stub 


     float x = img.getScaleX(); 
     float y = img.getScaleY(); 

     img.setScaleX((float) (x-1)); 
     img.setScaleY((float) (y-1)); 
    } 
}); 
} 

替代選項，其中有在建變焦控制器Web視圖加載圖像。

如下：

String page = "<html><body><center><img src=\""+path to your image+"\"/></center></body></html>"; 
    webView.loadDataWithBaseURL("fake",page, "text/html", "UTF-8",""); 

如果你不想使用生成的Web視圖縮放控制器，那麼你可以把你自己的按鈕，並在應用放大和縮小的Web視圖如下：

webView.setInitialScale(ZOOM_LEVEL);