我有图片压缩的一个类你看看哈: import com.xmobileapp.pictureviewer.R; import android.app.Activity; import android.content.Context; import android.graphics.Bitmap; import android.graphics.BitmapFactory; import android.graphics.BlurMaskFilter; import android.graphics.Canvas; import android.graphics.Paint; import android.graphics.Rect; import android.graphics.drawable.Drawable; import android.os.Bundle; import android.os.Handler; import android.util.AttributeSet; import android.view.GestureDetector; import android.view.KeyEvent; import android.view.MotionEvent; import android.view.View; import android.view.Window; import android.view.GestureDetector.SimpleOnGestureListener; import android.widget.Scroller;public class PictureShow extends Activity { private PictureShowUtils mAllImages = new PictureShowUtils(); boolean mLayoutComplete; boolean mPausing = false; PictureSlideView mPictureSlideView; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); requestWindowFeature(Window.FEATURE_CUSTOM_TITLE); setContentView(R.layout.main); mPictureSlideView = (PictureSlideView) findViewById(R.id.grid); mPictureSlideView.requestFocus(); } @Override public boolean onKeyUp(int keyCode, KeyEvent event) { return super.onKeyUp(keyCode, event); } @Override public boolean onKeyDown(int keyCode, KeyEvent event) { int sel = mPictureSlideView.mSelImageIndex; int count = mAllImages.getCount(); switch (keyCode) { case KeyEvent.KEYCODE_DPAD_UP: if (sel >= 1) { sel--; mPictureSlideView.ScrollUp(); } break; case KeyEvent.KEYCODE_DPAD_DOWN: if (sel < count - 1) { sel++; mPictureSlideView.scrollDown(); } break; default: break; } mPictureSlideView.mSelImageIndex = sel; mPictureSlideView.mImageBlockManager.loadSelBlock(sel); mPictureSlideView.invalidate(); return super.onKeyDown(keyCode, event); } @Override public void onPause() { super.onPause(); mPausing = true; } @Override public void onResume() { super.onResume(); mPausing = false; }
public static class PictureSlideView extends View { // 布局信息 class LayoutSpec { LayoutSpec(int cols, int w, int h, int leftEdgePadding, int rightEdgePadding, int intercellSpacing) { mColumns = cols; mCellWidth = w; mCellHeight = h; mLeftEdgePadding = leftEdgePadding; mRightEdgePadding = rightEdgePadding; mCellSpacing = intercellSpacing; } int mColumns; int mCellWidth, mCellHeight; int mLeftEdgePadding, mRightEdgePadding; int mCellSpacing; }; private class ImageBlockManager { private int mBlockCacheFirstBlockNumber = 0; private int mBlockCacheStartOffset = 0; //缩略图缓存 private ImageBlock[] mBlockCache; //选定的缩略图对象 private ImageBlock mSelBlock; //一屏上缩略图的行数 private static final int sRowsPerPage = 4; //缩略图缓存大小参数 private static final int sPagesPreCache = 2; private static final int sPagesPostCache = 2; // 放大预览图的尺寸 private static final int sSelBlockWidth = 200; private static final int sSelBlockHeight = 200; private Bitmap mMissingImageThumbnailBitmap; ImageBlockManager(Context context) { mContext = context; mBlockCache = new ImageBlock[sRowsPerPage * (sPagesPreCache + sPagesPostCache + 1)]; for (int i = 0; i < mBlockCache.length; i++) { mBlockCache[i] = new ImageBlock(); } /* 读取图片 */ loadBlocks(); mSelBlock = new ImageBlock(sSelBlockWidth, sSelBlockHeight); } int blockHeight() { return mCurrentSpec.mCellSpacing + mCurrentSpec.mCellHeight + mCurrentSpec.mCellSpacing; } int blockWidth() { return mCurrentSpec.mCellSpacing + mCurrentSpec.mCellWidth + mCurrentSpec.mCellSpacing; } void loadSelBlock(int pos) { mSelBlock.loadSelImage(pos); } private void paintSelBlock(Canvas canvas) { int pos = mSelImageIndex; if (pos < 0) return; Bitmap b = mSelBlock.mBitmap; if (b == null) { return; } int xPos = 0; int yPos = 0; yPos = mScrollY + mCurrentSpec.mCellSpacing; xPos = mCurrentSpec.mCellWidth + mCurrentSpec.mLeftEdgePadding; canvas.drawBitmap(b, xPos, yPos, mGridViewPaint); } // 获取代表“没有缩略图”的图片对象 public Bitmap getErrorBitmap() { mMissingImageThumbnailBitmap = BitmapFactory.decodeResource( PictureSlideView.this.getResources(), R.drawable.nothumbnail); return mMissingImageThumbnailBitmap; }
接上private void loadBlocks() { ImageBlock[] blocks = mBlockCache; int numBlocks = blocks.length; int first = 0; for (int i = 0; i < numBlocks; i++) { int j = first + i; if (j >= numBlocks) j -= numBlocks; ImageBlock b = blocks[j]; b.mBlockNumber = j; if (b.loadBlock() == 0) break; } } void doDraw(Canvas canvas) { ImageBlockManager.ImageBlock[] blocks = mBlockCache; if (blocks[0] == null) { return; } final int thisHeight = getHeight(); final int height = blocks[0].mBitmap.getHeight(); final int scrollPos = mScrollY; int currentBlock = (scrollPos < 0) ? ((scrollPos - height + 1) / height) : (scrollPos / height); while (true) { final int yPos = currentBlock * height; if (yPos >= scrollPos + thisHeight) { break; } int effectiveOffset = (mBlockCacheStartOffset + (currentBlock++ - mBlockCacheFirstBlockNumber)) % blocks.length; ImageBlock block = blocks[effectiveOffset]; if (block == null) break; Bitmap b = block.mBitmap; if (b == null) { break; } canvas.drawBitmap(b, 0, yPos, mGridViewPaint); } // end of while /* Paint Selection */ paintSelBlock(canvas); }/* end of doDraw */ private class ImageBlock { private static final int mBlurRadius = 5; private static final int mBlockAlpha = 180; private static final int mBorderAlpha = 180; private static final int mSelBorderAlpha = 150; Drawable mCellOutline; Bitmap mBitmap; Canvas mCanvas; Paint mPaint = new Paint(); int mBlockNumber; boolean mIsVisible; ImageBlock() { mBitmap = Bitmap.createBitmap(getWidth(), blockHeight(), Bitmap.Config.ARGB_8888); mCanvas = new Canvas(mBitmap); mPaint.setTextSize(14F); mPaint.setStyle(Paint.Style.FILL); mPaint.setAlpha(mBlockAlpha); mBlockNumber = -1; mCellOutline = PictureSlideView.this.getResources() .getDrawable(android.R.drawable.gallery_thumb); mCellOutline.setAlpha(mBorderAlpha); } ImageBlock(int w, int h) { mBitmap = Bitmap .createBitmap(w, h, Bitmap.Config.ARGB_8888); mCanvas = new Canvas(mBitmap); mPaint.setTextSize(14F); mPaint.setStyle(Paint.Style.FILL); mPaint.setFilterBitmap(true); mPaint.setMaskFilter(new BlurMaskFilter(mBlurRadius, BlurMaskFilter.Blur.NORMAL)); mBlockNumber = -1; mCellOutline = PictureSlideView.this.getResources() .getDrawable(android.R.drawable.gallery_thumb); mCellOutline.setAlpha(mSelBorderAlpha); } private int loadBlock() { int count = mGallery.mAllImages.getCount(); int base = (mBlockNumber * mCurrentSpec.mColumns); for (int col = 0; col < mCurrentSpec.mColumns; col++) { int spacing = mCurrentSpec.mCellSpacing; int leftSpacing = mCurrentSpec.mLeftEdgePadding; final int yPos = spacing; final int xPos = leftSpacing + (col * (mCurrentSpec.mCellWidth + spacing)); int pos = base + col; if (pos >= count) break; Bitmap b = mGallery.mAllImages.getImageAt(pos); if (b == null) { return 0; } drawBlockBitmap(b, xPos, yPos, mCurrentSpec.mCellWidth, mCurrentSpec.mCellHeight); } return 1; } private int loadSelImage(int pos) { final int yPos = 0; final int xPos = 0; Bitmap b = mGallery.mAllImages.getImageAt(pos); drawSelBlockBitmap(b, xPos, yPos, sSelBlockWidth, sSelBlockHeight); return 1; } private void drawBlockBitmap(Bitmap b, int left, int top, int width, int height) { mCanvas.setBitmap(mBitmap); if (b != null) { //根据图片的大小进行裁剪或缩放,形状均为正方形。 int w = width; int h = height; int bw = b.getWidth(); int bh = b.getHeight(); int deltaW = bw - w; int deltaH = bh - h; if (deltaW < 10 && deltaH < 10) { int halfDeltaW = deltaW / 2; int halfDeltaH = deltaH / 2; android.graphics.Rect src = new android.graphics.Rect( 0 + halfDeltaW, 0 + halfDeltaH, bw - halfDeltaW, bh - halfDeltaH); android.graphics.Rect dst = new android.graphics.Rect( left, top, left + w, top + h); mCanvas.drawBitmap(b, src, dst, mPaint); } else { int l = (bw - w) / 2; int t = (bh - h) / 2; android.graphics.Rect src = new android.graphics.Rect( l, t, l + w, t + h); android.graphics.Rect dst = new android.graphics.Rect( left, top, left + w, top + h); mCanvas.drawBitmap(b, src, dst, mPaint); } } else { //如果缩略图不能获得,则使用默认的错误图片代替 Bitmap error = mImageBlockManager.getErrorBitmap(); int w = error.getWidth(); int h = error.getHeight(); Rect source = new Rect(0, 0, w, h); int l = (w - w) / 2 + left; int t = (h - h) / 2 + top; Rect dest = new Rect(l, t, l + w, t + h); mCanvas.drawBitmap(error, source, dest, mPaint); } int[] stateSet = EMPTY_STATE_SET; paintBorder(stateSet, left, top, left + width, top + height); }
接上: //绘制选定的图片 private void drawSelBlockBitmap(Bitmap b, int left, int top, int width, int height) { mCanvas.setBitmap(mBitmap); mBitmap.eraseColor(0); if (b != null) { //根据目标正方形的尺寸调整图片大小 int w = width; int h = height; int bw = b.getWidth(); int bh = b.getHeight(); int deltaW = bw - w; int deltaH = bh - h; if (deltaW < 10 && deltaH < 10) { int halfDeltaW = deltaW / 2; int halfDeltaH = deltaH / 2; android.graphics.Rect src = new android.graphics.Rect( 0 + halfDeltaW, 0 + halfDeltaH, bw - halfDeltaW, bh - halfDeltaH); android.graphics.Rect dst = new android.graphics.Rect( left, top, left + w, top + h); mCanvas.drawBitmap(b, src, dst, mPaint); } else { int l = (bw - w) / 2; int t = (bh - h) / 2; android.graphics.Rect src = new android.graphics.Rect( l, t, l + w, t + h); android.graphics.Rect dst = new android.graphics.Rect( left, top, left + w, top + h); mCanvas.drawBitmap(b, src, dst, mPaint); } } else { // 如果没有获取到图片,则填充代表"图片不存在"的默认图片 Bitmap error = mImageBlockManager.getErrorBitmap(); int w = error.getWidth(); int h = error.getHeight(); Rect source = new Rect(0, 0, w, h); int l = (w - w) / 2 + left; int t = (h - h) / 2 + top; Rect dest = new Rect(l, t, l + w, t + h); mCanvas.drawBitmap(error, source, dest, mPaint); } int[] stateSet = EMPTY_STATE_SET; paintBorder(stateSet, left + 1, top + 1, left + width - 1, top + height - 1); } //绘制边框 private void paintBorder(int[] stateSet, int l, int t, int r, int b) { mCellOutline.setState(stateSet); mCanvas.setBitmap(mBitmap); mCellOutline.setBounds(l, t, r, b); mCellOutline.draw(mCanvas); } }// end of class ImageBlock } // end of class ImageBlockManager
这个就算recycle也没用了...
我觉得你可以这样,创建一张全局的bitmap(当然要按最大的创建),然后每个图片读取都按照字节的方式读出来,之后set个体这个全局的bitmap,显示的时候就显示这个全局的,一个用完就清空一下,在读取另一张,这样保证只有一个bitmap在占用内存....
import com.xmobileapp.pictureviewer.R;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.BlurMaskFilter;
import android.graphics.Canvas;
import android.graphics.Paint;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.os.Bundle;
import android.os.Handler;
import android.util.AttributeSet;
import android.view.GestureDetector;
import android.view.KeyEvent;
import android.view.MotionEvent;
import android.view.View;
import android.view.Window;
import android.view.GestureDetector.SimpleOnGestureListener;
import android.widget.Scroller;public class PictureShow extends Activity { private PictureShowUtils mAllImages = new PictureShowUtils();
boolean mLayoutComplete;
boolean mPausing = false;
PictureSlideView mPictureSlideView; /** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);
setContentView(R.layout.main);
mPictureSlideView = (PictureSlideView) findViewById(R.id.grid);
mPictureSlideView.requestFocus();
} @Override
public boolean onKeyUp(int keyCode, KeyEvent event) {
return super.onKeyUp(keyCode, event);
} @Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
int sel = mPictureSlideView.mSelImageIndex;
int count = mAllImages.getCount(); switch (keyCode) {
case KeyEvent.KEYCODE_DPAD_UP:
if (sel >= 1) {
sel--;
mPictureSlideView.ScrollUp();
}
break;
case KeyEvent.KEYCODE_DPAD_DOWN:
if (sel < count - 1) {
sel++;
mPictureSlideView.scrollDown();
} break;
default:
break;
} mPictureSlideView.mSelImageIndex = sel; mPictureSlideView.mImageBlockManager.loadSelBlock(sel);
mPictureSlideView.invalidate(); return super.onKeyDown(keyCode, event);
} @Override
public void onPause() {
super.onPause();
mPausing = true;
} @Override
public void onResume() {
super.onResume();
mPausing = false;
}
public static class PictureSlideView extends View {
// 布局信息
class LayoutSpec {
LayoutSpec(int cols, int w, int h, int leftEdgePadding,
int rightEdgePadding, int intercellSpacing) {
mColumns = cols;
mCellWidth = w;
mCellHeight = h;
mLeftEdgePadding = leftEdgePadding;
mRightEdgePadding = rightEdgePadding;
mCellSpacing = intercellSpacing;
} int mColumns;
int mCellWidth, mCellHeight;
int mLeftEdgePadding, mRightEdgePadding;
int mCellSpacing;
}; private class ImageBlockManager { private int mBlockCacheFirstBlockNumber = 0;
private int mBlockCacheStartOffset = 0;
//缩略图缓存
private ImageBlock[] mBlockCache;
//选定的缩略图对象
private ImageBlock mSelBlock;
//一屏上缩略图的行数
private static final int sRowsPerPage = 4;
//缩略图缓存大小参数
private static final int sPagesPreCache = 2;
private static final int sPagesPostCache = 2;
// 放大预览图的尺寸
private static final int sSelBlockWidth = 200;
private static final int sSelBlockHeight = 200; private Bitmap mMissingImageThumbnailBitmap; ImageBlockManager(Context context) {
mContext = context; mBlockCache = new ImageBlock[sRowsPerPage * (sPagesPreCache + sPagesPostCache + 1)];
for (int i = 0; i < mBlockCache.length; i++) {
mBlockCache[i] = new ImageBlock();
} /* 读取图片 */
loadBlocks(); mSelBlock = new ImageBlock(sSelBlockWidth, sSelBlockHeight); } int blockHeight() {
return mCurrentSpec.mCellSpacing + mCurrentSpec.mCellHeight
+ mCurrentSpec.mCellSpacing;
} int blockWidth() {
return mCurrentSpec.mCellSpacing + mCurrentSpec.mCellWidth
+ mCurrentSpec.mCellSpacing;
} void loadSelBlock(int pos) {
mSelBlock.loadSelImage(pos);
} private void paintSelBlock(Canvas canvas) {
int pos = mSelImageIndex;
if (pos < 0)
return; Bitmap b = mSelBlock.mBitmap;
if (b == null) {
return;
} int xPos = 0;
int yPos = 0; yPos = mScrollY + mCurrentSpec.mCellSpacing; xPos = mCurrentSpec.mCellWidth + mCurrentSpec.mLeftEdgePadding; canvas.drawBitmap(b, xPos, yPos, mGridViewPaint);
} // 获取代表“没有缩略图”的图片对象
public Bitmap getErrorBitmap() {
mMissingImageThumbnailBitmap = BitmapFactory.decodeResource(
PictureSlideView.this.getResources(),
R.drawable.nothumbnail); return mMissingImageThumbnailBitmap;
}
ImageBlock[] blocks = mBlockCache;
int numBlocks = blocks.length;
int first = 0; for (int i = 0; i < numBlocks; i++) {
int j = first + i;
if (j >= numBlocks)
j -= numBlocks;
ImageBlock b = blocks[j];
b.mBlockNumber = j;
if (b.loadBlock() == 0)
break;
} } void doDraw(Canvas canvas) {
ImageBlockManager.ImageBlock[] blocks = mBlockCache;
if (blocks[0] == null) {
return;
} final int thisHeight = getHeight();
final int height = blocks[0].mBitmap.getHeight();
final int scrollPos = mScrollY;
int currentBlock = (scrollPos < 0) ? ((scrollPos - height + 1) / height)
: (scrollPos / height); while (true) { final int yPos = currentBlock * height;
if (yPos >= scrollPos + thisHeight) {
break;
} int effectiveOffset = (mBlockCacheStartOffset + (currentBlock++ - mBlockCacheFirstBlockNumber))
% blocks.length; ImageBlock block = blocks[effectiveOffset];
if (block == null)
break; Bitmap b = block.mBitmap;
if (b == null) {
break;
}
canvas.drawBitmap(b, 0, yPos, mGridViewPaint);
} // end of while /* Paint Selection */
paintSelBlock(canvas); }/* end of doDraw */ private class ImageBlock { private static final int mBlurRadius = 5;
private static final int mBlockAlpha = 180;
private static final int mBorderAlpha = 180;
private static final int mSelBorderAlpha = 150; Drawable mCellOutline; Bitmap mBitmap;
Canvas mCanvas;
Paint mPaint = new Paint(); int mBlockNumber;
boolean mIsVisible; ImageBlock() { mBitmap = Bitmap.createBitmap(getWidth(), blockHeight(),
Bitmap.Config.ARGB_8888);
mCanvas = new Canvas(mBitmap); mPaint.setTextSize(14F);
mPaint.setStyle(Paint.Style.FILL);
mPaint.setAlpha(mBlockAlpha); mBlockNumber = -1;
mCellOutline = PictureSlideView.this.getResources()
.getDrawable(android.R.drawable.gallery_thumb);
mCellOutline.setAlpha(mBorderAlpha); } ImageBlock(int w, int h) { mBitmap = Bitmap
.createBitmap(w, h, Bitmap.Config.ARGB_8888);
mCanvas = new Canvas(mBitmap); mPaint.setTextSize(14F);
mPaint.setStyle(Paint.Style.FILL);
mPaint.setFilterBitmap(true);
mPaint.setMaskFilter(new BlurMaskFilter(mBlurRadius,
BlurMaskFilter.Blur.NORMAL)); mBlockNumber = -1;
mCellOutline = PictureSlideView.this.getResources()
.getDrawable(android.R.drawable.gallery_thumb);
mCellOutline.setAlpha(mSelBorderAlpha); } private int loadBlock() { int count = mGallery.mAllImages.getCount();
int base = (mBlockNumber * mCurrentSpec.mColumns); for (int col = 0; col < mCurrentSpec.mColumns; col++) { int spacing = mCurrentSpec.mCellSpacing;
int leftSpacing = mCurrentSpec.mLeftEdgePadding;
final int yPos = spacing;
final int xPos = leftSpacing
+ (col * (mCurrentSpec.mCellWidth + spacing)); int pos = base + col;
if (pos >= count)
break; Bitmap b = mGallery.mAllImages.getImageAt(pos);
if (b == null) {
return 0;
}
drawBlockBitmap(b, xPos, yPos, mCurrentSpec.mCellWidth, mCurrentSpec.mCellHeight);
} return 1;
} private int loadSelImage(int pos) { final int yPos = 0;
final int xPos = 0; Bitmap b = mGallery.mAllImages.getImageAt(pos);
drawSelBlockBitmap(b, xPos, yPos, sSelBlockWidth,
sSelBlockHeight); return 1;
} private void drawBlockBitmap(Bitmap b, int left, int top,
int width, int height) {
mCanvas.setBitmap(mBitmap); if (b != null) {
//根据图片的大小进行裁剪或缩放,形状均为正方形。
int w = width;
int h = height; int bw = b.getWidth();
int bh = b.getHeight(); int deltaW = bw - w;
int deltaH = bh - h; if (deltaW < 10 && deltaH < 10) {
int halfDeltaW = deltaW / 2;
int halfDeltaH = deltaH / 2;
android.graphics.Rect src = new android.graphics.Rect(
0 + halfDeltaW, 0 + halfDeltaH, bw
- halfDeltaW, bh - halfDeltaH);
android.graphics.Rect dst = new android.graphics.Rect(
left, top, left + w, top + h);
mCanvas.drawBitmap(b, src, dst, mPaint);
} else {
int l = (bw - w) / 2;
int t = (bh - h) / 2; android.graphics.Rect src = new android.graphics.Rect(
l, t, l + w, t + h);
android.graphics.Rect dst = new android.graphics.Rect(
left, top, left + w, top + h);
mCanvas.drawBitmap(b, src, dst, mPaint); }
} else {
//如果缩略图不能获得,则使用默认的错误图片代替
Bitmap error = mImageBlockManager.getErrorBitmap();
int w = error.getWidth();
int h = error.getHeight();
Rect source = new Rect(0, 0, w, h);
int l = (w - w) / 2 + left;
int t = (h - h) / 2 + top;
Rect dest = new Rect(l, t, l + w, t + h);
mCanvas.drawBitmap(error, source, dest, mPaint); }
int[] stateSet = EMPTY_STATE_SET; paintBorder(stateSet, left, top, left + width, top + height);
}
//绘制选定的图片
private void drawSelBlockBitmap(Bitmap b, int left, int top,
int width, int height) {
mCanvas.setBitmap(mBitmap);
mBitmap.eraseColor(0); if (b != null) {
//根据目标正方形的尺寸调整图片大小
int w = width;
int h = height; int bw = b.getWidth();
int bh = b.getHeight(); int deltaW = bw - w;
int deltaH = bh - h; if (deltaW < 10 && deltaH < 10) {
int halfDeltaW = deltaW / 2;
int halfDeltaH = deltaH / 2;
android.graphics.Rect src = new android.graphics.Rect(
0 + halfDeltaW, 0 + halfDeltaH, bw
- halfDeltaW, bh - halfDeltaH);
android.graphics.Rect dst = new android.graphics.Rect(
left, top, left + w, top + h);
mCanvas.drawBitmap(b, src, dst, mPaint);
} else {
int l = (bw - w) / 2;
int t = (bh - h) / 2; android.graphics.Rect src = new android.graphics.Rect(
l, t, l + w, t + h);
android.graphics.Rect dst = new android.graphics.Rect(
left, top, left + w, top + h);
mCanvas.drawBitmap(b, src, dst, mPaint); }
} else {
// 如果没有获取到图片,则填充代表"图片不存在"的默认图片
Bitmap error = mImageBlockManager.getErrorBitmap();
int w = error.getWidth();
int h = error.getHeight();
Rect source = new Rect(0, 0, w, h);
int l = (w - w) / 2 + left;
int t = (h - h) / 2 + top;
Rect dest = new Rect(l, t, l + w, t + h);
mCanvas.drawBitmap(error, source, dest, mPaint); }
int[] stateSet = EMPTY_STATE_SET; paintBorder(stateSet, left + 1, top + 1, left + width - 1,
top + height - 1);
} //绘制边框
private void paintBorder(int[] stateSet, int l, int t, int r,
int b) {
mCellOutline.setState(stateSet);
mCanvas.setBitmap(mBitmap);
mCellOutline.setBounds(l, t, r, b);
mCellOutline.draw(mCanvas); } }// end of class ImageBlock } // end of class ImageBlockManager
private Context mContext;
// 主界面的Activity
private PictureShow mGallery;
// 用于绘图的Paint对象
private Paint mGridViewPaint = new Paint();
private ImageBlockManager mImageBlockManager;
private LayoutSpec mCurrentSpec;
private int mScrollY = 0;
// 滑动对象
private Scroller mScroller = new Scroller(getContext());
// 用于判断用户动作的GestureDetector对象
private GestureDetector mGestureDetector;
// 选中图片的索引值
private int mSelImageIndex = 0; private void init(Context context) {
mContext = context;
mGridViewPaint.setColor(0xFF000000);
mGallery = (PictureShow) context; setVerticalScrollBarEnabled(true); mGestureDetector = new GestureDetector(
new SimpleOnGestureListener() { @Override
public boolean onDown(MotionEvent e) {
int touchSelIndex = computeSelImageIndex(e); if (touchSelIndex >= 0)
mImageBlockManager.loadSelBlock(touchSelIndex); invalidate(); return true;
} @Override
public void onShowPress(MotionEvent e) {
super.onShowPress(e);
}
});
} public PictureSlideView(Context context, AttributeSet attrs,
int defStyle) {
super(context, attrs, defStyle);
init(context);
} public PictureSlideView(Context context, AttributeSet attrs) {
super(context, attrs);
init(context);
} public PictureSlideView(Context context) {
super(context);
init(context);
} @Override
public void onLayout(boolean changed, int left, int top, int right,
int bottom) {
super.onLayout(changed, left, top, right, bottom); if (mGallery.isFinishing() || mGallery.mPausing) {
return;
} mCurrentSpec = new LayoutSpec(1, 100, 100, 8, 8, 10);
mGallery.mLayoutComplete = true; /* Create Image Manager */
if (mImageBlockManager == null) {
mImageBlockManager = new ImageBlockManager(mContext);
} } @Override
public boolean onTouchEvent(android.view.MotionEvent ev) { mGestureDetector.onTouchEvent(ev);
return true;
} int computeSelImageIndex(android.view.MotionEvent ev) { int spacing = mCurrentSpec.mCellSpacing;
int leftSpacing = mCurrentSpec.mLeftEdgePadding;
int bh = mImageBlockManager.blockHeight(); int x = (int) ev.getX();
int y = (int) ev.getY();
int maxHeight = bh * 4; if (y > maxHeight)
return -1; int row = (mScrollY + y - spacing)
/ (mCurrentSpec.mCellHeight + spacing);
int col = Math.min(mCurrentSpec.mColumns - 1, (x - leftSpacing)
/ (mCurrentSpec.mCellWidth + spacing));
return (row * mCurrentSpec.mColumns) + col;
} void ScrollUp() {
mScroller.startScroll(0, mScrollY, 0, -mImageBlockManager
.blockHeight(), 20);
computeScroll();
} void scrollDown() {
mScroller.startScroll(0, mScrollY, 0, mImageBlockManager
.blockHeight(), 20);
computeScroll();
}
//计算滑动
@Override
public void computeScroll() {
if (mScroller != null) {
boolean more = mScroller.computeScrollOffset();
scrollTo(0, (int) mScroller.getCurrY()); if (more)
postInvalidate();
else {
mScroller.forceFinished(true);
}
} else {
super.computeScroll();
} } @Override
public void scrollBy(int x, int y) {
scrollTo(x, mScrollY + y);
} @Override
public void scrollTo(int x, int y) {
mScrollY = y;
super.scrollTo(x, y);
}
public void onDraw(Canvas canvas) {
super.onDraw(canvas);
if (mImageBlockManager != null)
mImageBlockManager.doDraw(canvas);
} } // end of PictureSlideView}
Bitmap resizeBmp = null;
BitmapFactory.Options opts = new BitmapFactory.Options();
// 数字越大读出的图片占用的heap越小 不然总是溢出
if (f.length() < 20480) { // 0-20k
opts.inSampleSize = 1;
} else if (f.length() < 51200) { // 20-50k
opts.inSampleSize = 1;
} else if (f.length() < 307200) { // 50-300k
opts.inSampleSize = 1;
} else if (f.length() < 819200) { // 300-800k
opts.inSampleSize = 1;
} else if (f.length() < 1048576) { // 800-1024k
opts.inSampleSize = 1;
} else {
opts.inSampleSize = 1;
}
resizeBmp = BitmapFactory.decodeFile(f.getPath(), opts);
return resizeBmp;
}
public static Bitmap fitSizePic() {
File file = new File(path);
Bitmap bitMap = Util.fitSizePic(file);
Bitmap resizeBmp = null;
BitmapFactory.Options opts = new BitmapFactory.Options();
// 数字越大读出的图片占用的heap越小 不然总是溢出
if (f.length() < 20480) { // 0-20k
opts.inSampleSize = 1;
} else if (f.length() < 51200) { // 20-50k
opts.inSampleSize = 2;
} else if (f.length() < 307200) { // 50-300k
opts.inSampleSize = 4;
} else if (f.length() < 819200) { // 300-800k
opts.inSampleSize = 6;
} else if (f.length() < 1048576) { // 800-1024k
opts.inSampleSize = 8;
} else {
opts.inSampleSize = 10;
}
resizeBmp = BitmapFactory.decodeFile(f.getPath(), opts);
return resizeBmp;
}
1、修改android底层的内存限制放开内存
2、用楼上的做法进行缩放, opts.inSampleSize = 2;表明缩放为原图的长宽各一半用弱引用引用图片,保证及时的回收。。
调用了也不会立即执行垃圾回收的!
要记住,Java和C++不一样的垃圾回收虽好,但有时却很头疼