무효화 호출을 사용해야합니까? 그렇다면 어디에서?

Question

뷰를 보여주는 액티비티가 있는데 뷰 내에 캔버스가 그려져있는 경우 캔버스를 드래그/줌할 수있는 ontouch 기능이 있습니다. 그러나 디버깅 할 때 캔버스의 움직임이 없으면 제대로 작동하는 것처럼 보입니다. 무효화를해야한다고 생각합니다. 그렇죠? 그렇다면 어디에서 불러야합니까?

도움을 주셔서 감사합니다. 화면을 원하는 경우에 대한

Touch.java

package org.example.touch; 

import android.app.Activity; 
import android.content.Context; 
import android.graphics.Matrix; 
import android.graphics.PointF; 
import android.os.Bundle; 
import android.util.FloatMath; 
import android.util.Log; 
import android.view.MotionEvent; 
import android.view.View; 
import android.view.View.OnTouchListener; 
import android.widget.ImageView; 

public class Touch extends Activity implements OnTouchListener { 
    private static final String TAG = "Touch"; 
    // 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 void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 
     setContentView(R.layout.main); 
     GridView view = new GridView(this); 
     setContentView(view); 
     // ImageView view = (ImageView) findViewById(R.id.imageView); 
     view.setOnTouchListener(this); 

     // ... 
     // Work around a Cupcake bug 
     matrix.setTranslate(1f, 1f); 
     view.setImageMatrix(matrix); 

    } 

    @Override 
    public boolean onTouch(View v, MotionEvent rawEvent) { 
     WrapMotionEvent event = WrapMotionEvent.wrap(rawEvent); 
     // ... 
     GridView view = (GridView) 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()); 
     Log.d(TAG, "mode=DRAG"); 
     mode = DRAG; 
     break; 
     case MotionEvent.ACTION_POINTER_DOWN: 
     oldDist = spacing(event); 
     Log.d(TAG, "oldDist=" + oldDist); 
     if (oldDist > 10f) { 
      savedMatrix.set(matrix); 
      midPoint(mid, event); 
      mode = ZOOM; 
      Log.d(TAG, "mode=ZOOM"); 
     } 
     break; 
     case MotionEvent.ACTION_UP: 
     case MotionEvent.ACTION_POINTER_UP: 
     mode = NONE; 
     Log.d(TAG, "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); 
      Log.d(TAG, "newDist=" + newDist); 
      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(WrapMotionEvent 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()); 
    } 

    /** 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); 
    } 
} 

하고 뷰, GridView.java

package org.example.touch; 

import android.app.Activity; 
import android.os.Bundle; 

import android.view.View; 
import android.content.Context; 
import android.graphics.Canvas; 
import android.graphics.Color; 
import android.graphics.Paint; 
import android.graphics.Paint.Style; 
import android.view.Display; 
import android.graphics.Path; 
import android.graphics.Bitmap; 
import android.graphics.Matrix; 
import android.graphics.Bitmap.Config; 
import android.widget.ImageView; 


public class GridView extends ImageView { 

    private int canvasWidth; 
    private int canvasHeight; 

    // private Config config; 
    // private Bitmap bitmap; 
    // private Canvas canvas; 

    public GridView(Context context) { 
     super(context); 




    // config = Bitmap.Config.ARGB_8888; 
    // bitmap = Bitmap.createBitmap(canvasWidth, canvasHeight, config); 
    // canvas = new Canvas(bitmap); 

    } 


public void onDraw(Canvas canvas){ 
    super.onDraw(canvas); 

    canvasWidth = canvas.getWidth(); 
    canvasHeight = canvas.getHeight(); 

    Paint paint = new Paint(); 
    paint.setStyle(Paint.Style.FILL); 

    paint.setColor(Color.WHITE); 
    canvas.drawPaint(paint); 


    canvas.drawRect(0, 0, (float)canvasWidth, (float)canvasHeight, paint); 

    int Grid_size = canvasWidth/32; 


    paint.setStyle(Style.STROKE); 
     paint.setColor(Color.RED); 
     for (int i = 1; i < 100; i++) {     
       canvas.drawLine((Grid_size*i), 10, (Grid_size*i), 10+(Grid_size*10), paint);    
       }     
     paint.setColor(Color.RED); 
      for (int i = 1; i < 12; i++) {         
        canvas.drawLine(10, (Grid_size*i), (Grid_size*99), (Grid_size*i), paint); 
      } 
      final int FS= 500;     //Sampling Frequency 
      final int WIN=FS*20; 

      //create a test sine wave 
      short[]wave = new short[WIN]; 
      int frequency = 1; 
      int amplitude = 40; 
      for (int n=0; n<WIN; n++) 
       wave[n] = (short) (60.0+amplitude*Math.sin(6.282*frequency*n/FS)); 

      //To display the waveform 

      Path path2 = new Path(); 
      path2.moveTo(10, 60); 

      for (float x2=1; x2<WIN; x2++) 
       path2.lineTo(10+(3*x2/50), wave[(int) x2]); 
      Paint paint3 = new Paint(); 
      paint3.setColor(Color.BLACK); 
      paint3.setStyle(Style.STROKE); 
      canvas.drawPath(path2, paint3); 
} 


//public void invalidate(); 

public void setImageMatrix(Matrix matrix) { 
    super.setImageMatrix(matrix); 

}} 

Answer 1

전화 무효가 다시 그려야합니다. 끊임없이 업데이트하고 싶다면 onDraw 단계가 끝날 때 호출 할 수 있습니다. 당신이 확대 된 후

만 화면이 필요하면

다시 그립니다하기 위해 다음 줌 기능이