如何设置Drawable的ImageResource

Question

我创建了一个网格视图滑动应用程序，我想在其中添加捏缩放功能

我从本教程中找到了这段代码

http://www.c-sharpcorner.com/UploadFile/88b6e5/multi-touch-panning-pinch-zoom-image-view-in-android-using/

//
int[] images = MainActivity.ICONS;
Pinch img = new Pinch(this);
img.setImageResource(images);
img.setMaxZoom(4f);
setContentView(img);
//

在这段代码中

img.setImageResource(image);

这里我想从数组而不是drawable中设置图像资源。

查看我的代码：

MainActivity.java

package com.td.gridview;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewGroup.LayoutParams;
import android.view.ViewTreeObserver;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.RelativeLayout;
import android.widget.TextView;
import android.widget.AdapterView.OnItemClickListener;

public class MainActivity extends Activity {


    private GridView photoGrid;
    private int mPhotoSize, mPhotoSpacing;
    private ImageAdapter imageAdapter;

    // Some items to add to the GRID
    private static final String[] CONTENT = new String[] 
            { 
            "Akon", "Justin Bieber", "AlRight", "Big Sean",
            "Britney Spears", "Hilary", "Micheal Buble", "Akon", "Justin Bieber", "AlRight", "Big Sean",
            "Britney Spears", "Hilary", "Micheal Buble", "Britney Spears", "Hilary", "Micheal Buble", "Akon",
            "Justin Bieber", "AlRight", "Big Sean", "Britney Spears", "Hilary", "Micheal Buble", "Akon",
            "Justin Bieber", "AlRight", "Big Sean", "Britney Spears", "Hilary", "Micheal Buble", "Akon",
            "Justin Bieber", "AlRight", "Big Sean", "Britney Spears", "Hilary", "Micheal Buble", "Britney Spears",
            "Hilary", "Micheal Buble", "Akon", "Justin Bieber", "AlRight", "Big Sean", "Britney Spears", "Hilary",
            "Micheal Buble" 
            };
    static final int[] ICONS = new int[] 
            { 
            R.drawable.cover_akon, R.drawable.cover_justin,
            R.drawable.cover_alright, R.drawable.cover_big_sean, R.drawable.cover_britney, R.drawable.cover_hilary,
            R.drawable.cover_mb, R.drawable.cover_akon, R.drawable.cover_justin, R.drawable.cover_alright,
            R.drawable.cover_big_sean, R.drawable.cover_britney, R.drawable.cover_hilary, R.drawable.cover_mb,
            R.drawable.cover_britney, R.drawable.cover_hilary, R.drawable.cover_mb, R.drawable.cover_akon,
            R.drawable.cover_justin, R.drawable.cover_alright, R.drawable.cover_big_sean, R.drawable.cover_britney,
            R.drawable.cover_hilary, R.drawable.cover_mb, R.drawable.cover_akon, R.drawable.cover_justin,
            R.drawable.cover_alright, R.drawable.cover_big_sean, R.drawable.cover_britney, R.drawable.cover_hilary,
            R.drawable.cover_mb, R.drawable.cover_akon, R.drawable.cover_justin, R.drawable.cover_alright,
            R.drawable.cover_big_sean, R.drawable.cover_britney, R.drawable.cover_hilary, R.drawable.cover_mb,
            R.drawable.cover_britney, R.drawable.cover_hilary, R.drawable.cover_mb, R.drawable.cover_akon,
            R.drawable.cover_justin, R.drawable.cover_alright, R.drawable.cover_big_sean, R.drawable.cover_britney,
            R.drawable.cover_hilary, R.drawable.cover_mb 
            };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);



        // get the photo size and spacing
        mPhotoSize = getResources().getDimensionPixelSize(R.dimen.photo_size);
        mPhotoSpacing = getResources().getDimensionPixelSize(R.dimen.photo_spacing);

        // initialize image adapter
        imageAdapter = new ImageAdapter();

        photoGrid = (GridView) findViewById(R.id.albumGrid);

        //start sent image to full screen             

        /**
         * On Click event for Single Gridview Item
         * */
        photoGrid.setOnItemClickListener(new OnItemClickListener() {
            @Override
            public void onItemClick(AdapterView<?> parent, View v,
                    int position, long id) {

                // Sending image id to FullScreenActivity
                Intent i = new Intent(getApplicationContext(), SwipeActivity.class);
                // passing array index
                i.putExtra("id", position);
                startActivity(i);
            }
        });
        //end sent image to full screen

        // set image adapter to the GridView
        photoGrid.setAdapter(imageAdapter);

        // get the view tree observer of the grid and set the height and numcols dynamically
        photoGrid.getViewTreeObserver().addOnGlobalLayoutListener(new ViewTreeObserver.OnGlobalLayoutListener() {
            @Override
            public void onGlobalLayout() {
                if (imageAdapter.getNumColumns() == 0) {
                    final int numColumns = (int) Math.floor(photoGrid.getWidth() / (mPhotoSize + mPhotoSpacing));
                    if (numColumns > 0) {
                        final int columnWidth = (photoGrid.getWidth() / numColumns) - mPhotoSpacing;
                        imageAdapter.setNumColumns(numColumns);
                        imageAdapter.setItemHeight(columnWidth);

                    }
                }
            }
        });
    }

    // ///////// ImageAdapter class /////////////////
    public class ImageAdapter extends BaseAdapter {
        private LayoutInflater mInflater;
        private int mItemHeight = 0;
        private int mNumColumns = 0;
        private RelativeLayout.LayoutParams mImageViewLayoutParams;

        public ImageAdapter() {
            mInflater = (LayoutInflater) getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            mImageViewLayoutParams = new RelativeLayout.LayoutParams(LayoutParams.MATCH_PARENT,
                    LayoutParams.MATCH_PARENT);
        }

        public int getCount() {
            return CONTENT.length;
        }

        // set numcols
        public void setNumColumns(int numColumns) {
            mNumColumns = numColumns;
        }

        public int getNumColumns() {
            return mNumColumns;
        }

        // set photo item height
        public void setItemHeight(int height) {
            if (height == mItemHeight) {
                return;
            }
            mItemHeight = height;
            mImageViewLayoutParams = new RelativeLayout.LayoutParams(LayoutParams.MATCH_PARENT, mItemHeight);
            notifyDataSetChanged();
        }

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

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

        public View getView(final int position, View view, ViewGroup parent) {

            if (view == null)
                view = mInflater.inflate(R.layout.photo_item, null);

            ImageView cover = (ImageView) view.findViewById(R.id.cover);
            TextView title = (TextView) view.findViewById(R.id.title);

            cover.setLayoutParams(mImageViewLayoutParams);

            // Check the height matches our calculated column width
            if (cover.getLayoutParams().height != mItemHeight) {
                cover.setLayoutParams(mImageViewLayoutParams);
            }

            cover.setImageResource(ICONS[position % ICONS.length]);
            title.setText(CONTENT[position % CONTENT.length]);

            return view;
        }
    }

}

SwipActivity.java

package com.td.gridview;

import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;

public class SwipeActivity extends Activity 
{   

  @Override
  public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.swipe_view);

 // get intent data
    Intent i = getIntent();

    // Selected image id
    int position = i.getExtras().getInt("id");

    ViewPager viewPager = (ViewPager) findViewById(R.id.view_pager);
    ImagePagerAdapter adapter = new ImagePagerAdapter();
    viewPager.setAdapter(adapter);
    viewPager.setCurrentItem(position);

    //
    int[] images = MainActivity.ICONS;
    Pinch img = new Pinch(this);
    img.setImageResource(images);   
    img.setMaxZoom(4f);
    setContentView(img);
    //

  }

  private class ImagePagerAdapter extends PagerAdapter 
  {
      int[] icons = MainActivity.ICONS;    

    @Override
    public int getCount() 
    {
      return icons.length;
    }

    @Override
    public boolean isViewFromObject(View view, Object object) 
    {
      return view == ((ImageView) object);
    }

    @Override
    public Object instantiateItem(ViewGroup container, int position) 
    {
      Context context = SwipeActivity.this;
      ImageView imageView = new ImageView(context);
//      int padding = context.getResources().getDimensionPixelSize(
//          R.dimen.padding_large);
//      imageView.setPadding(padding, padding, padding, padding);
      imageView.setScaleType(ImageView.ScaleType.CENTER_INSIDE);
      imageView.setImageResource(icons[position]);
      ((ViewPager) container).addView(imageView, 0);
      return imageView;
    }

    @Override
    public void destroyItem(ViewGroup container, int position, Object object) 
    {
      ((ViewPager) container).removeView((ImageView) object);
    }
  }
}

Pinch.java

package com.td.gridview;

import android.content.Context;

import android.graphics.Matrix;

import android.graphics.PointF;

import android.graphics.drawable.Drawable;

import android.support.v4.view.ViewPager;
import android.util.AttributeSet;

import android.util.Log;

import android.view.MotionEvent;
import android.view.ViewGroup;

import android.view.ScaleGestureDetector;

import android.view.View;

import android.widget.ImageView;



public class Pinch extends ImageView {



    Matrix 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 last = new PointF();

    PointF start = new PointF();

    float minScale = 1f;

    float maxScale = 3f;

    float[] m;



    int viewWidth, viewHeight;

    static final int CLICK = 3;

    float saveScale = 1f;

    protected float origWidth, origHeight;

    int oldMeasuredWidth, oldMeasuredHeight;



    ScaleGestureDetector mScaleDetector;



    Context context;



    public Pinch(Context context) {

        super(context);

        sharedConstructing(context);

    }



    public Pinch(Context context, AttributeSet attrs) {

        super(context, attrs);

        sharedConstructing(context);

    }



    private void sharedConstructing(Context context) {

        super.setClickable(true);

        this.context = context;

        mScaleDetector = new ScaleGestureDetector(context, new ScaleListener());

        matrix = new Matrix();

        m = new float[9];

        setImageMatrix(matrix);

        setScaleType(ScaleType.MATRIX);



        setOnTouchListener(new OnTouchListener() {



            @Override

            public boolean onTouch(View v, MotionEvent event) {

                mScaleDetector.onTouchEvent(event);

                PointF curr = new PointF(event.getX(), event.getY());



                switch (event.getAction()) {

                    case MotionEvent.ACTION_DOWN:

                       last.set(curr);

                        start.set(last);

                        mode = DRAG;

                        break;



                    case MotionEvent.ACTION_MOVE:

                        if (mode == DRAG) {

                            float deltaX = curr.x - last.x;

                            float deltaY = curr.y - last.y;

                            float fixTransX = getFixDragTrans(deltaX, viewWidth, origWidth * saveScale);

                            float fixTransY = getFixDragTrans(deltaY, viewHeight, origHeight * saveScale);

                            matrix.postTranslate(fixTransX, fixTransY);

                            fixTrans();

                            last.set(curr.x, curr.y);

                        }

                        break;



                    case MotionEvent.ACTION_UP:

                        mode = NONE;

                        int xDiff = (int) Math.abs(curr.x - start.x);

                        int yDiff = (int) Math.abs(curr.y - start.y);

                        if (xDiff < CLICK && yDiff < CLICK)

                            performClick();

                        break;



                    case MotionEvent.ACTION_POINTER_UP:

                        mode = NONE;

                        break;

                }



                setImageMatrix(matrix);

                invalidate();

                return true; // indicate event was handled

            }



        });

    }



    public void setMaxZoom(float x) {

        maxScale = x;

    }



    private class ScaleListener extends ScaleGestureDetector.SimpleOnScaleGestureListener {

        @Override

        public boolean onScaleBegin(ScaleGestureDetector detector) {

            mode = ZOOM;

            return true;

        }



        @Override

        public boolean onScale(ScaleGestureDetector detector) {

            float mScaleFactor = detector.getScaleFactor();

            float origScale = saveScale;

            saveScale *= mScaleFactor;

            if (saveScale > maxScale) {

                saveScale = maxScale;

                mScaleFactor = maxScale / origScale;

            } else if (saveScale < minScale) {

                saveScale = minScale;

                mScaleFactor = minScale / origScale;

            }



            if (origWidth * saveScale <= viewWidth || origHeight * saveScale <= viewHeight)

                matrix.postScale(mScaleFactor, mScaleFactor, viewWidth / 2, viewHeight / 2);

            else

                matrix.postScale(mScaleFactor, mScaleFactor, detector.getFocusX(), detector.getFocusY());



            fixTrans();

            return true;

        }

    }



    void fixTrans() {

        matrix.getValues(m);

        float transX = m[Matrix.MTRANS_X];

        float transY = m[Matrix.MTRANS_Y];



        float fixTransX = getFixTrans(transX, viewWidth, origWidth * saveScale);

        float fixTransY = getFixTrans(transY, viewHeight, origHeight * saveScale);



        if (fixTransX != 0 || fixTransY != 0)

            matrix.postTranslate(fixTransX, fixTransY);

    }



    float getFixTrans(float trans, float viewSize, float contentSize) {

        float minTrans, maxTrans;



        if (contentSize <= viewSize) {

            minTrans = 0;

            maxTrans = viewSize - contentSize;

        } else {

            minTrans = viewSize - contentSize;

            maxTrans = 0;

        }



        if (trans < minTrans)

            return -trans + minTrans;

        if (trans > maxTrans)

            return -trans + maxTrans;

        return 0;

    }



    float getFixDragTrans(float delta, float viewSize, float contentSize) {

        if (contentSize <= viewSize) {

            return 0;

        }

        return delta;

    }



    @Override

    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {

        super.onMeasure(widthMeasureSpec, heightMeasureSpec);

        viewWidth = MeasureSpec.getSize(widthMeasureSpec);

        viewHeight = MeasureSpec.getSize(heightMeasureSpec);



        //

        // Rescales image on rotation

        //

        if (oldMeasuredHeight == viewWidth && oldMeasuredHeight == viewHeight

                || viewWidth == 0 || viewHeight == 0)

            return;

        oldMeasuredHeight = viewHeight;

        oldMeasuredWidth = viewWidth;



        if (saveScale == 1) {

            //Fit to screen.

            float scale;



            Drawable drawable = getDrawable();

            if (drawable == null || drawable.getIntrinsicWidth() == 0 || drawable.getIntrinsicHeight() == 0)

                return;

            int bmWidth = drawable.getIntrinsicWidth();

            int bmHeight = drawable.getIntrinsicHeight();



            Log.d("bmSize", "bmWidth: " + bmWidth + " bmHeight : " + bmHeight);



            float scaleX = (float) viewWidth / (float) bmWidth;

            float scaleY = (float) viewHeight / (float) bmHeight;

            scale = Math.min(scaleX, scaleY);

            matrix.setScale(scale, scale);



            // Center the image

            float redundantYSpace = (float) viewHeight - (scale * (float) bmHeight);

            float redundantXSpace = (float) viewWidth - (scale * (float) bmWidth);

            redundantYSpace /= (float) 2;

            redundantXSpace /= (float) 2;



            matrix.postTranslate(redundantXSpace, redundantYSpace);



            origWidth = viewWidth - 2 * redundantXSpace;

            origHeight = viewHeight - 2 * redundantYSpace;

            setImageMatrix(matrix);

        }

        fixTrans();

    }

}

Answer 1

替换这一行

imageView.setImageResource(icons[position]);

通过

 imageView.setImageResource(MainActivity.ICONS[position]);

Answer 2

试试这个

img.setImageResource(images[position]);