如何在 Android 中将类传递给 ImageSwitcher？

Question

我正在使用 ImageSwitcher 来显示图片列表。当用户从 A.class 中的 Listview 中选择一个项目时，将调用 ImageSwitcher 并且用户查看图片。如果在列表中单击第 1 项，则应将一组特定的可绘制对象传递给图像切换器。如果单击列表中的第 2 项，则会显示一组不同的图片。我一直在努力解决如何将可绘制对象从 A.class 传递到 ImageSwitcher。

总之： 我想将一类可绘制对象从 A.class 传递到 ImageSwitcher，这样，如果单击项目 1，

private Integer[] mThumb = {R.Drawable.pic1, R.Drawable.pic2, R.Drawable.pic3}

则在 ImageSwitcher 中： 如果单击项目 2，我希望在 ImageSwitcher 中： private Integer[] mThumb = [R. Drawable.pic6, R.Drawable.pic7, R.Drawable.pic8}

从发送活动中，到目前为止我已经尝试了使用 putExtra 的许多排列putIntegralArrayExtra 等等。我确信这个问题的答案非常基本。我是java新手，并且仍在（缓慢）学习。感谢您的帮助！

这是图像切换器的代码，因此您可以明白我所说的 int[] mThumb 的含义：

public class ImageSwitch1 extends Activity implements
        AdapterView.OnItemSelectedListener, ViewSwitcher.ViewFactory, OnTouchListener {


    Matrix matrix = new Matrix();
    Matrix eventMatrix = new Matrix();

    final static int NONE = 0;
    final static int DRAG = 1;
    final static int ZOOM = 2;
    int touchState = NONE;




    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        requestWindowFeature(Window.FEATURE_NO_TITLE);

        setContentView(R.layout.imageswitcher);


        mSwitcher = (ImageSwitcher) findViewById(R.id.switcher);
        mSwitcher.setFactory(this);
        mSwitcher.setInAnimation(AnimationUtils.loadAnimation(this,
                android.R.anim.fade_in));
        mSwitcher.setOutAnimation(AnimationUtils.loadAnimation(this,
                android.R.anim.fade_out));


        Gallery g = (Gallery) findViewById(R.id.gallery);
        g.setAdapter(new ImageAdapter(this));
        g.setOnItemSelectedListener(this);


    }


    public void onItemSelected(AdapterView parent, View v, int position, long id) {
        mSwitcher.setImageResource(mImage[position]);
        final TextView tv = (TextView)findViewById(R.id.SwitcherText);
        tv.setText(mText[position]);    



    }  



    public void onNothingSelected(AdapterView parent) {
    }

    public View makeView() {
        ImageView i = new ImageView(this);
        i.setScaleType(ScaleType.MATRIX);
        i.setBackgroundColor(0xFF000000);
        i.setScaleType(ImageView.ScaleType.FIT_CENTER);
        i.setLayoutParams(new ImageSwitcher.LayoutParams(LayoutParams.MATCH_PARENT,
                LayoutParams.MATCH_PARENT));
        i.setOnTouchListener(this);
        return i;
    }
    final static float MIN_DIST = 50;
    static float eventDistance = 0;
    static float centerX =0, centerY = 0;
    public boolean onTouch(View v, MotionEvent event) {
        ImageView i = (ImageView) v;
        switch (event.getAction() & MotionEvent.ACTION_MASK) {
        case MotionEvent.ACTION_DOWN:
        //primary touch event starts: remember touch down location
        touchState = DRAG;
        centerX = event.getX(0);
        centerY = event.getY(0);
        eventMatrix.set(matrix);
        break;
        case MotionEvent.ACTION_POINTER_DOWN:
        //secondary touch event starts: remember distance and center
        eventDistance = calcDistance(event);
        calcMidpoint(centerX, centerY, event);
        if (eventDistance > MIN_DIST) {
        eventMatrix.set(matrix);
        touchState = ZOOM;
        }
        break;
        case MotionEvent.ACTION_MOVE:
            if (touchState == DRAG) {
            //single finger drag, translate accordingly
            matrix.set(eventMatrix);
            matrix.setTranslate(event.getX(0) - centerX,
            event.getY(0) - centerY);
            } else if (touchState == ZOOM) {
            //multi-finger zoom, scale accordingly around center
            float dist = calcDistance(event);
            if (dist > MIN_DIST) {
            matrix.set(eventMatrix);
            float scale = dist / eventDistance;
            matrix.postScale(scale, scale, centerX, centerY);
            }
            }
            // Perform the transformation
            i.setImageMatrix(matrix);
            break;
            case MotionEvent.ACTION_UP:
            case MotionEvent.ACTION_POINTER_UP:
            touchState = NONE;
            break;
            }
            return true;
            }
            private float calcDistance(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 calcMidpoint(float centerX, float centerY,
            MotionEvent event) {
            centerX = (event.getX(0) + event.getX(1))/2;
            centerY = (event.getY(0) + event.getY(1))/2;
            }    


    private ImageSwitcher mSwitcher;

    public class ImageAdapter extends BaseAdapter {
        public ImageAdapter(Context c) {
            mContext = c;
        }

        public int getCount() {

        return mThumb.length;

        }

        public Object getItem(int position) {
            return position;
        }

        public long getItemId(int position) {
            return position;
        }

        public View getView(int position, View convertView, ViewGroup parent) {
            ImageView im = new ImageView(mContext);
            im.setImageResource(mThumb[position]);
            im.setAdjustViewBounds(true);
            im.setLayoutParams(new Gallery.LayoutParams(
            LayoutParams.WRAP_CONTENT, LayoutParams.WRAP_CONTENT));
            im.setBackgroundResource(R.drawable.picture_frame);


            return im;
        }
        private Context mContext;
    }




  //these are the little pictures  
    private Integer[] mThumb = {
         R.drawable.lp_image1_thumb, R.drawable.lp_image2_thumb, R.drawable.lp_image3_thumb,
         R.drawable.lp_image4_thumb, R.drawable.lp_image5_thumb, R.drawable.lp_image6_thumb,
         R.drawable.lp_image7_thumb, R.drawable.lp_image8_thumb, R.drawable.lp_image9_thumb,
         R.drawable.lp_image10_thumb};

Answer 1

这个想法是你必须为列表视图中选定的项目创建一个索引（你可以使用listview.selectedItem）并实现侦听器来进行图像切换。

当用户从 A.class 中的 Listview 中选择一个项目时，将调用 ImageSwitcher...如果在列表中单击项目 1，则应将一组特定的可绘制对象传递给图像切换器。

实现ListView.setOnItemSelectedListener。你已经拥有了。

用户查看图片

实现OnTouchListener。你也已经有了它，但你必须添加图像切换。您可以使用滑动技术切换它，然后检查索引以了解您必须加载哪一组图片。只需为所选图片集中的当前图像提供 INDEX2 即可。

更新您的代码，然后我会指导您。

Answer 2

这是我的做法，它可以工作，尽管它可能相当笨重：

发送活动：

if(position == 0)
{
int[] mThumb =
 {
 R.drawable.lp_image1,R.drawable.lp_image2, R.drawable.lp_image3, R.drawable.lp_image4,R.drawable.lp_image5, R.drawable.lp_image6, R.drawable.lp_image7,R.drawable.lp_image8,R.drawable.lp_image9
    }; 
myIntent = new Intent(view.getContext(), LP.class);
b.putIntArray("mImage", mImage);
b.putInt("i", 0);
}

接收活动：

Bundle b=this.getIntent().getExtras();
int[] mThumb = b.getIntArray("mThumbSent");
ImageAdapter adapter = new ImageAdapter(this, mThumb);

可以在任何需要的地方重复此代码，以从发送活动中引入 int[]