捏放大和圖像視圖的拖動遠離屏幕？

Question

我需要拖拽縮放圖像視圖。我瀏覽了互聯網，並從here獲得代碼。它運行良好，但是當我縮放更多時，它會超出屏幕。我想保持屏幕內的縮放和拖動。我嘗試了以下方法，但對我無效。

我將imageview的Tanslate屬性設置爲：
matrix.setTranslate(width/2, height/2);
其中寬度和高度是屏幕寬度和高度。

我試圖檢查此條件，但它從來沒有幫助過我：

case MotionEvent.ACTION_MOVE: 

    if (mode == DRAG) { 

    int newX = event.getX() - start.x; 
    int newY = event.getY() - start.y; 
    if ((newX <= 0 || newX >= screenWidth) || 
      (newY <= 0 || newY >= screenHeight)) 
     break; 

    matrix.set(savedMatrix); 
    matrix.postTranslate(newX, newY); 

完整的源代碼：

public class Touch extends Activity { 

// 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; 

// Widgets 

private Gallery galleryIcons; 
private Intent intent; 
private ImageLoader imageloader = null; 
private String filePath = null; 
private Uri myUri = null; 
private Bitmap preview_bitmap = null; 
private Utils utils = null; 
private ImageView imgRawBg; 
private View adminIcons = null; 
private View icon_cost_description = null; 
public ProgressDialog mProgressDialog; 
public ProgressDialog mProgDiagSndToServer; 
private String uploadStatus = null; 

private Activity activity; 
private InputStream is; 
private ImageView imgIcon; 
private TextView txtImgMetaTitle; 
private TextView txtImgTitle; 
private TextView txtImgDesc; 
private TextView btnImgPrice; 
private TextView btnImgCancel; 
private Dialog inAppDialog; 
private TextView txtTitle; 
private Button btnBuyIcon; 
private Button btnCancelDialog; 
protected int mIconIndex = 0; 
private View yesOrNoConfirmation; 
private ImageButton btnOkConfirm; 
private ImageButton btnCancel; 
private ImageView imgToDragAndPan; 
private FrameLayout saveImage; 
private File imageFile; 
private File photo; 
private boolean serverUploadException = false; 
private String uploadPhotoID = null; 

static int height; 
static int width; 

private static final float MIN_ZOOM = 1.0f; 
private static final float MAX_ZOOM = 5.0f; 

// Menus and its properties 

private static final int CHANGE_TOUCH_MODE_MENU_ID = Menu.FIRST; 
private static final int SAVE_PROCESSED_IMAGE = 3; 
public static final boolean Debugging = false; 

@Override 
public void onCreate(Bundle savedInstanceState) { 
    super.onCreate(savedInstanceState); 
    requestWindowFeature(Window.FEATURE_NO_TITLE); 
    getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, 
      WindowManager.LayoutParams.FLAG_FULLSCREEN); 
    setContentView(R.layout.dragview); 

    DisplayMetrics metrics = new DisplayMetrics(); 
    getWindowManager().getDefaultDisplay().getMetrics(metrics); 
    height = metrics.heightPixels; 
    width = metrics.widthPixels; 

    setupViews(); 

    imgToDragAndPan.setOnTouchListener(new View.OnTouchListener() { 

     public boolean onTouch(View v, MotionEvent rawEvent) { 
      WrapMotionEvent event = WrapMotionEvent.wrap(rawEvent); 
      ImageView view = (ImageView) v; 

      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) { 

       int newX = event.getX() - start.x; 
    int newY = event.getY() - start.y; 
    if ((newX <= 0 || newX >= screenWidth) || 
     (newY <= 0 || newY >= screenHeight)) 
    break; 


        matrix.set(savedMatrix); 
        matrix.postTranslate(newX, newY); 

        // 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; 
     } 
    }); 

    matrix.setTranslate(width/2, height/2); 
    // matrix.setTranslate(1f, 1f); 

    imgToDragAndPan.setImageMatrix(matrix); 

    BitmapFactory.Options options = new BitmapFactory.Options(); 
    options.inSampleSize = 4; 
    preview_bitmap = BitmapFactory.decodeStream(is, null, options); 

    galleryIcons = (Gallery) findViewById(R.id.galleryIcons); 
    galleryIcons.setOnItemClickListener(new OnItemClickListener() { 
     public void onItemClick(AdapterView<?> arg0, View arg1, int index, 
       long arg3) { 
      mIconIndex = index; 
      if (SplashScreen.adminIcons.get(index).getPaymentType() 
        .equals("0")) { 

       imageloader.DisplayImage(SplashScreen.adminIcons.get(index) 
         .getLargeIcons(), imgToDragAndPan); 
       imgToDragAndPan.setVisibility(View.VISIBLE); 
       adminIcons.setVisibility(View.VISIBLE); 
       icon_cost_description.setVisibility(View.GONE); 

      } else { 
       imgToDragAndPan.setVisibility(View.GONE); 
       adminIcons.setVisibility(View.GONE); 
       icon_cost_description.setVisibility(View.VISIBLE); 
       imageloader.DisplayImage(SplashScreen.adminIcons.get(index) 
         .getSmallIcons(), imgIcon); 
       txtImgMetaTitle.setText(SplashScreen.adminIcons.get(index) 
         .getName()); 
       txtImgTitle.setText(SplashScreen.adminIcons.get(index) 
         .getName()); 
       txtImgDesc.setText(SplashScreen.adminIcons.get(index) 
         .getDescription()); 
       btnImgPrice.setText(SplashScreen.adminIcons.get(index) 
         .getPrice()); 
       btnImgCancel.setText(Constant.cancel); 
      } 
     } 
    }); 

    btnImgCancel.setOnClickListener(new View.OnClickListener() { 
     public void onClick(View v) { 
      adminIcons.setVisibility(View.VISIBLE); 
      icon_cost_description.setVisibility(View.GONE); 
     } 
    }); 

    btnImgPrice.setOnClickListener(new View.OnClickListener() { 
     public void onClick(View v) { 
      ShowBuyDialog(); 
     } 
    }); 

    btnOkConfirm.setOnClickListener(new View.OnClickListener() { 
     public void onClick(View v) { 
      if (utils.isConnectingToInternet(Touch.this)) { 
       new UploadImagesToServer().execute(); 
      } else { 
       utils.showToast(getApplicationContext(), 
         Constant.noNetworkConnection); 
      } 
     } 
    }); 

    btnCancel.setOnClickListener(new View.OnClickListener() { 
     public void onClick(View v) { 
      imgToDragAndPan.setEnabled(true); 
      adminIcons.setVisibility(View.VISIBLE); 
      icon_cost_description.setVisibility(View.GONE); 
      yesOrNoConfirmation.setVisibility(View.GONE); 
     } 
    }); 

    activity.runOnUiThread(new Runnable() { 
     public void run() { 
      mProgressDialog = ProgressDialog.show(Touch.this, 
        "Please wait...", "Loading.."); 

      File photo = new File(myUri.getPath()); 
      preview_bitmap = utils.decodeFile(photo); 
      imgRawBg.setImageBitmap(preview_bitmap); 
      galleryIcons.setAdapter(new AdminIconsAdapter(Touch.this, 
        SplashScreen.adminIcons)); 

      if (mProgressDialog.isShowing() && mProgressDialog != null) { 
       mProgressDialog.dismiss(); 
      } 
     } 
    }); 
} 

public boolean onCreateOptionsMenu(Menu menu) { 
    super.onCreateOptionsMenu(menu); 
    menu.add(0, CHANGE_TOUCH_MODE_MENU_ID, 0, "Show/Hide"); 
    menu.add(0, SAVE_PROCESSED_IMAGE, 0, "Save Image"); 
    return true; 
} 

public boolean onPrepareOptionsMenu(Menu menu) { 

    if (yesOrNoConfirmation.isShown()) { 
     menu.findItem(SAVE_PROCESSED_IMAGE).setVisible(false); 
     menu.findItem(CHANGE_TOUCH_MODE_MENU_ID).setVisible(false); 
    } else { 
     menu.findItem(SAVE_PROCESSED_IMAGE).setVisible(true); 
     menu.findItem(CHANGE_TOUCH_MODE_MENU_ID).setVisible(true); 
    } 
    return super.onPrepareOptionsMenu(menu); 
} 

public boolean onOptionsItemSelected(MenuItem item) { 
    switch (item.getItemId()) { 
    case CHANGE_TOUCH_MODE_MENU_ID: { 

     if (adminIcons.isShown()) { 
      adminIcons.setVisibility(View.GONE); 
     } else { 
      adminIcons.setVisibility(View.VISIBLE); 
     } 
     return true; 
    } 
    case SAVE_PROCESSED_IMAGE: { 
     imgToDragAndPan.setEnabled(false); 
     adminIcons.setVisibility(View.GONE); 
     icon_cost_description.setVisibility(View.GONE); 
     saveProcessedImage(); 
     processedImgHandler.sendEmptyMessageDelayed(0, 500); 
    } 
    } 
    return super.onOptionsItemSelected(item); 
} 

Handler processedImgHandler = new Handler() { 
    @Override 
    public void handleMessage(Message msg) { 
     preview_bitmap = utils.decodeFile(imageFile); 
     yesOrNoConfirmation.setVisibility(View.VISIBLE); 
     super.handleMessage(msg); 
    } 
}; 

private void saveProcessedImage() { 

    photo = new File(Environment.getExternalStorageDirectory() 
      + "/Mashallah", "photoToShare.png"); 

    // create bitmap screen capture 
    Bitmap bitmap = null; 
    View v1 = saveImage.getRootView(); 
    v1.setDrawingCacheEnabled(true); 
    bitmap = Bitmap.createBitmap(v1.getDrawingCache()); 
    v1.setDrawingCacheEnabled(false); 
    OutputStream outStream = null; 
    imageFile = new File(photo.getAbsolutePath()); 

    try { 
     outStream = new FileOutputStream(photo.getAbsolutePath()); 
     bitmap.compress(Bitmap.CompressFormat.PNG, 100, outStream); 
     outStream.flush(); 
     outStream.close(); 

    } catch (FileNotFoundException e) { 

    } catch (IOException e) { 

    } 
} 

private void setupViews() { 
    utils = new Utils(); 
    intent = getIntent(); 
    imageloader = new ImageLoader(Touch.this); 
    activity = this; 
    filePath = intent.getStringExtra("filePath"); 
    myUri = Uri.parse(filePath); 
    imgToDragAndPan = (ImageView) findViewById(R.id.imgToDrag); 
    imgRawBg = (ImageView) findViewById(R.id.imgbg); 

    // imgToDragAndPan.getLayoutParams().height = height; 
    // imgToDragAndPan.getLayoutParams().width = width; 
    // imgToDragAndPan.setMaxHeight(height); 
    // imgToDragAndPan.setMaxWidth(width); 
    // 
    // imgRawBg.getLayoutParams().height = height; 
    // imgRawBg.getLayoutParams().width = width; 
    // imgRawBg.setMaxHeight(height); 
    // imgRawBg.setMaxWidth(width); 

    icon_cost_description = (View) findViewById(R.id.icon_cost_description); 
    adminIcons = (View) findViewById(R.id.adminIcons); 
    yesOrNoConfirmation = (View) findViewById(R.id.confirm_yes_or_no); 
    saveImage = (FrameLayout) findViewById(R.id.saveImage); 

    // Icon_cost_description 

    imgIcon = (ImageView) findViewById(R.id.imgIcon); 
    txtImgMetaTitle = (TextView) findViewById(R.id.txtImgMetaTitle); 
    txtImgTitle = (TextView) findViewById(R.id.txtImgTitle); 
    txtImgDesc = (TextView) findViewById(R.id.txtImgDesc); 
    btnImgPrice = (TextView) findViewById(R.id.btnImgPrice); 
    btnImgCancel = (TextView) findViewById(R.id.btnImgCancel); 

    // Confirm_yes_no layout 

    btnOkConfirm = (ImageButton) findViewById(R.id.btnOkConfirm); 
    btnCancel = (ImageButton) findViewById(R.id.btnCancel); 

    // Setting visibility 

    imgToDragAndPan.setVisibility(View.INVISIBLE); 
    yesOrNoConfirmation.setVisibility(View.GONE); 
    icon_cost_description.setVisibility(View.GONE); 

} 




/** Determine the space between the first two fingers */ 
private float spacing(WrapMotionEvent 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, WrapMotionEvent event) { 
    float x = event.getX(0) + event.getX(1); 
    float y = event.getY(0) + event.getY(1); 
    point.set(x/2, y/2); 
} 

} 

Answer 1

嘗試使用event.getRawX()和getRawY();

和比較語句檢查如果drag是比屏幕寬度或高度。它應該是一些像

int newX = event.getRawX();//or +/- the current width of the element under drag 
int newY = event.getRawY(); 
if ((newX <= 0 || newX >= screenWidth) || 
     (newY <= 0 || newY >= screenHeight)) 
    break; 

請檢查是否有幫助。

Answer 2

試試這個，

我要給你一個解決方案，我希望它會爲你工作，

try to use TouchImageView instead of ImageView in Layout.because touchimageview have property that zooming in or out itself 

https://github.com/MikeOrtiz/TouchImageView from this link you learn how to use touchimageview... 

<com.luminous.pick.TouchImageView 
       android:id="@+id/img2" 
       android:layout_width="match_parent" 
       android:layout_height="match_parent" /> 

Then After implement onDragListener of imageview so you can get DRAG And Drop of Imageview easily... 

@Override 
public boolean onDrag(View v, DragEvent event) { 

    switch (event.getAction()) { 

     case DragEvent.ACTION_DROP: 

      ImageView target = (ImageView) v; 
      ImageView dragged = (ImageView) event.getLocalState(); 

      Drawable target_draw = target.getDrawable(); 
      Drawable dragged_draw = dragged.getDrawable(); 

      dragged.setImageDrawable(target_draw); 
      target.setImageDrawable(dragged_draw); 

    } 
    return true; 
} 

我希望你很快解決您的問題....