使用多個圖像的Android圖像動畫

Question

我正在尋找一個動畫自由的代碼，它將幫助我使用一組圖像（水平旋轉約60張圖像）來完成360度動畫。此外圖像在SDCARD中，而不是在應用程序中。

謝謝

Answer 1

可以創建自定義視圖，並重寫的onDraw（Canvas）的方法和繪製所希望的圖象的位圖。

您可以跟蹤當前度數的「方向」，並使用Canvas.drawBitmap（Bitmap，Matrix，Paint）計算應在哪個位置顯示哪個位置。

下面是根據手機方向移動一個圖像的示例。

import android.content.Context; 
import android.graphics.Bitmap; 
import android.graphics.Bitmap.Config; 
import android.graphics.BitmapFactory; 
import android.graphics.BitmapFactory.Options; 
import android.graphics.Canvas; 
import android.graphics.Color; 
import android.graphics.Matrix; 
import android.graphics.Paint; 
import android.graphics.PixelFormat; 
import android.graphics.Rect; 
import android.util.AttributeSet; 
import android.util.Log; 
import android.view.MotionEvent; 
import android.view.SurfaceView; 
import android.view.View; 
import android.view.View.OnTouchListener; 

public class SkySurfaceView extends SurfaceView implements OnTouchListener { 

    private static final String TAG = SkySurfaceView.class.getSimpleName(); 
    private double viewPortX, viewPortY; 
    private int starX, starY; 
    private Bitmap target; 
    private int targetWidth, targetHeight; 
    private int vpWidth, vpHeight; 
    private Matrix skyMatrix, skyMatrix2; 
    private Matrix skyMatrix3; 
    private Bitmap star; 
    private Paint paint; 
    private Rect touchRect, touchRect2, touchRect3; 

    public SkySurfaceView(Context context, AttributeSet attr) { 
     super(context, attr); 
     viewPortX = viewPortY = 0; 
     skyMatrix = new Matrix(); 
     skyMatrix2 = new Matrix(); 
     skyMatrix3 = new Matrix(); 

     paint = new Paint(); 
     paint.setStrokeWidth(1); 
     paint.setDither(true); 

     paint.setColor(Color.RED); 
     Options opt = new Options(); 
     opt.inSampleSize = 2; 
     opt.inScaled = false; 
     opt.inPreferredConfig = Config.RGB_565; 
     star = BitmapFactory.decodeResource(getResources(), R.drawable.star, 
              opt); 
     touchRect = new Rect(0, 0, star.getWidth(), star.getHeight()); 
     touchRect2 = new Rect(0, 0, star.getWidth(), star.getHeight()); 
     touchRect3 = new Rect(0, 0, star.getWidth(), star.getHeight()); 

     this.setWillNotDraw(true); 
     setLayerType(View.LAYER_TYPE_HARDWARE, null); 
     this.setOnTouchListener(this); 
     getHolder().setFormat(PixelFormat.RGB_565); 
    } 

    public void setTarget(Bitmap b) { 
     target = b; 

     targetHeight = target.getHeight(); 
     targetWidth = target.getWidth(); 
    } 

    public void init() { 

     this.starX = (int) (vpWidth * Math.random()) + vpWidth; 
     this.starY = (int) ((vpHeight - star.getHeight()) * Math.random()); 
     Log.i(TAG, "drawn star on " + starX + "," + starY); 
     Canvas c = new Canvas(); 
     Log.i(TAG, 
       "target dimension is " + target.getWidth() + "x" 
       + target.getHeight()); 
     Bitmap bitmap = Bitmap.createBitmap(target.getWidth(), 
              target.getHeight(), Config.RGB_565); 
     c.setBitmap(bitmap); 
     c.drawBitmap(target, 0, 0, paint); 
     c.drawBitmap(star, starX, starY, paint); 
     c.drawBitmap(star, starX - targetWidth, starY, paint); 
     target.recycle(); 
     setTarget(bitmap); 
     setWillNotDraw(false); 

    } 

    @Override 
    public boolean performClick() { 
     super.performClick(); 
     return false; 
    } 

    /** 
    * 
    * @param x 
    *   - [-1:1] 
    * @param y 
    *   - [-1:1] 
    */ 
    public void setViewPort(double x, double y) { 

     viewPortX = x; 
     viewPortY = y; 

     int tempX = (int) (targetWidth * (viewPortX)); 
     int tempY = (int) (targetHeight * (viewPortY - 1)); 

     tempY = Math.max(tempY, -(targetHeight - vpHeight)/2); 
     tempY = Math.min(tempY, +(targetHeight - vpHeight/2)); 

     Log.i(TAG, 
       String.format("%d %d , %d %d, %d %d", tempX, tempY, tempX 
          - targetWidth, tempY, tempX + targetWidth, tempY)); 

     skyMatrix.reset(); 
     skyMatrix.postTranslate(tempX, tempY); 
     skyMatrix2.reset(); 
     skyMatrix2.postTranslate(tempX - targetWidth, tempY); 
     skyMatrix3.reset(); 
     skyMatrix3.postTranslate(tempX + targetWidth, tempY); 

     int xx = (tempX + starX); 
     while (xx < targetWidth) { 
      xx += targetWidth; 
     } 
     touchRect.offsetTo(xx % targetWidth, (tempY + starY) % targetHeight); 
     touchRect2.offsetTo(xx % targetWidth - targetWidth, (tempY + starY) 
          % targetHeight); 
     touchRect3.offsetTo(xx % targetWidth + targetWidth, (tempY + starY) 
          % targetHeight); 
     postInvalidate(); 
    } 

    public void setViewportSize(int x, int y) { 
     vpWidth = x; 
     vpHeight = y; 
    } 

    @Override 
    protected void onDraw(Canvas c) { 
     super.onDraw(c); 
     c.drawBitmap(target, skyMatrix, paint); 
     c.drawBitmap(target, skyMatrix2, paint); 
     c.drawBitmap(target, skyMatrix3, paint); 
    } 

    @Override 
    public boolean onTouch(View v, MotionEvent event) { 
     float ex = event.getX(); 
     float ey = event.getY(); 

     Log.i(TAG, "touched " + ex + " " + ey); 
     if (touchRect.contains((int) ex, (int) ey)) { 
      if (listener != null) { 
       listener.onCaptured(); 
      } 
     } else if (touchRect2.contains((int) ex, (int) ey)) { 
      if (listener != null) { 
       listener.onCaptured(); 
      } 
     } else if (touchRect3.contains((int) ex, (int) ey)) { 
      if (listener != null) { 
       listener.onCaptured(); 
      } 
     } 

     return false; 
    } 


    public void setListener(OnStarCaptureListener listener) { 
     this.listener = listener; 
    } 

} 

在這個例子中，「target」是一個天空圖像。每當setViewPort被調用時，（x和y [-1：1]），圖像的繪圖矩陣被更新，並且調用「invalidate（）」。 onDraw（）方法調用將使用偏移量繪製「目標」。