Pinching Zoom für Textansicht

Question

Ich möchte Pinching-Funktionalität (vergrößern/verkleinern) für die Textansicht.

Ich habe schon zu viele Tutorials verweisen aber keine fruchtbare ..bitte Hilfe mich immer, wenn jemand es getan haben, oder weiß, wie es zu tun ....

Kann ich es auch mit Taste wie hinein- und herauszoomen und/oder mit 2-Finger-Pinching?

jede mögliche Hilfe würde geschätzt .. dank

nicht funktionierenden Code:

setContentView(R.layout.main); 
    mainView =(LinearLayout)findViewById(R.id.linearLayout); 

    Button buttonZoomOut = (Button)findViewById(R.id.buttonZoomOut); 
    Button buttonNormal = (Button)findViewById(R.id.buttonNormal); 
    Button buttonZoomIn = (Button)findViewById(R.id.buttonZoomIn); 

    buttonZoomOut.setOnClickListener(new View.OnClickListener() {  
    public void onClick(View v) { 
    zoom(0.5f,0.5f,new PointF(0,0));  
    } 
    }); 
    buttonNormal.setOnClickListener(new OnClickListener() { 

    public void onClick(View v) { 
    zoom(1f,1f,new PointF(0,0)); 
    } 
    }); 
    buttonZoomIn.setOnClickListener(new View.OnClickListener() { 

    public void onClick(View v) { 
    zoom(2f,2f,new PointF(0,0)); 
    } 
    }); 
} 

/** zooming is done from here */ 
public void zoom(Float scaleX,Float scaleY,PointF pivot){ 
    mainView.setPivotX(pivot.x); 
    mainView.setPivotY(pivot.y); 
    mainView.setScaleX(scaleX); 
    mainView.setScaleY(scaleY); 
} 

Answer 1

Wenn Sie Fingerklemm implementieren möchten, können Sie diese sample code von Google-Entwickler Blog sehen.

Ich habe es vorher versucht. Es funktioniert und ist gut zum Lernen.

Answer 2

Sie können folgenden Code versuchen .... Es konvertiert TextView zu Bild n Thene können Sie es zoomen.

public class Temp erweitert Aktivität implementiert OnTouchListener {

private static final String TAG = "Touch"; 

private static final float MIN_ZOOM = 1.0f; 

private static final float MAX_ZOOM = 5.0f; 

// 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; 

// public static Arraylist str;

@Override 
public void onCreate(Bundle savedInstanceState) { 

    super.onCreate(savedInstanceState); 

TextView tv = new TextView(this); 
    LinearLayout.LayoutParams layoutParamsForText = new LinearLayout.LayoutParams(
      width,height); 
    tv.setLayoutParams(layoutParamsForText); 

    Bitmap testB; 

    testB = Bitmap.createBitmap(width, height, Bitmap.Config.ARGB_8888); 
    Canvas c = new Canvas(testB); 
    tv.layout(0, 0, width, height); 
    tv.draw(c); 

    ImageView view = (ImageView) findViewById(R.id.test_X); 
    view.setLayoutParams(layoutParamsForText); 
    view.setBackgroundColor(Color.WHITE); 
    view.setImageBitmap(testB); 
    view.setMaxHeight(height); 
    view.setMaxWidth(width); 
    // ImageView view = (ImageView) findViewById(R.id.test_X); 

    // view.setLayoutParams(new GridView.LayoutParams(85, 85)); 

    view.setScaleType(ImageView.ScaleType.FIT_CENTER); 

    view.setOnTouchListener(this); 
} 

public boolean onTouch(View v, MotionEvent event) { 

    ImageView view = (ImageView) v; 

    view.setScaleType(ImageView.ScaleType.MATRIX); 

    float scale; 

    // Dump touch event to log 

    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"); 

     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: // 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) { // movement of first finger 

      matrix.set(savedMatrix); 

      if (view.getLeft() >= -392) { 

       matrix.postTranslate(event.getX() - start.x, event.getY() 
         - start.y); 

      } 

     } 

     else if (mode == ZOOM) { // pinch zooming 

      float newDist = spacing(event); 

      Log.d(TAG, "newDist=" + newDist); 

      if (newDist > 5f) { 

       matrix.set(savedMatrix); 

       scale = newDist/oldDist; /* 
              * thinking i need to play 
              * around with this value to 
              * limit it 
              */ 

       matrix.postScale(scale, scale, mid.x, mid.y); 

      } 

     } 

     break; 

    } 

    // Perform the transformation 

    view.setImageMatrix(matrix); 

    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); 

} 

/** 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("]"); 

    Log.d(TAG, sb.toString()); 

}