編輯:關於Android編程
ZoomImageView.java:
復制代碼 代碼如下:
/**
* @author gongchaobin
*
* 自定義可伸縮的ImageView
*/
public class ZoomImageView extends View{
/** 畫筆類 **/
private Paint mPaint;
private Runnable mRefresh = null;
/** 縮放手勢監聽類 **/
private ScaleGestureDetector mScaleDetector;
/** 手勢識別類 **/
private GestureDetector mGestureDetector;
/** 當前被渲染的Bitmap **/
private Bitmap mBitmap;
private int mThisWidth = -1, mThisHeight = -1;
private Runnable mOnLayoutRunnable = null;
private Matrix mBaseMatrix = new Matrix();
private Matrix mDisplayMatrix = new Matrix();
private Matrix mSuppMatrix = new Matrix();
private Matrix mMatrix = new Matrix();
/** 最大的拉伸比例 **/
private float mMaxZoom;
private float[] mMatrixValues = new float[9];
private Runnable mFling = null;
private double mLastDraw = 0;
static final int sPaintDelay = 250;
public ZoomImageView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
// TODO Auto-generated constructor stub
init();
}
public ZoomImageView(Context context, AttributeSet attrs) {
super(context, attrs);
// TODO Auto-generated constructor stub
init();
}
public ZoomImageView(Context context) {
super(context);
// TODO Auto-generated constructor stub
init();
}
private void init() {
mPaint = new Paint();
// 圖像抖動處理
mPaint.setDither(true);
// 過濾優化操作 加快顯示
mPaint.setFilterBitmap(true);
// 去掉鋸齒
mPaint.setAntiAlias(true);
/** 刷新線程 **/
mRefresh = new Runnable() {
@Override
public void run() {
postInvalidate();
}
};
mScaleDetector = new ScaleGestureDetector(getContext(),new ScaleListener());
mGestureDetector = new GestureDetector(getContext(),new MyGestureListener());
// 判斷是否是新的API 開啟硬件加速
if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB) {
setLayerType(View.LAYER_TYPE_HARDWARE, null);
}
}
public Bitmap getImageBitmap() {
return mBitmap;
}
/** 回收Bitmap **/
public void clear() {
if(mBitmap != null && !mBitmap.isRecycled()) {
mBitmap.recycle();
mBitmap = null;
}
}
@Override
protected void onLayout(boolean changed, int left, int top, int right,
int bottom) {
// TODO Auto-generated method stub
super.onLayout(changed, left, top, right, bottom);
mThisWidth = right - left;
mThisHeight = bottom - top;
Runnable r = mOnLayoutRunnable;
if (r != null) {
mOnLayoutRunnable = null;
r.run();
}
if (mBitmap != null) {
setBaseMatrix(mBitmap, mBaseMatrix);
setImageMatrix(getImageViewMatrix());
}
}
private void setBaseMatrix(Bitmap bitmap, Matrix matrix) {
float viewWidth = getWidth();
float viewHeight = getHeight();
matrix.reset();
float widthScale = Math.min(viewWidth / (float)bitmap.getWidth(), 1.0f);
float heightScale = Math.min(viewHeight / (float)bitmap.getHeight(), 1.0f);
float scale;
if (widthScale > heightScale) {
scale = heightScale;
} else {
scale = widthScale;
}
/** 算取比例 進行平移 **/
matrix.setScale(scale, scale);
matrix.postTranslate(
(viewWidth - ((float)bitmap.getWidth() * scale))/2F,
(viewHeight - ((float)bitmap.getHeight() * scale))/2F);
}
protected Matrix getImageViewMatrix() {
mDisplayMatrix.set(mBaseMatrix);
mDisplayMatrix.postConcat(mSuppMatrix);
return mDisplayMatrix;
}
public void setImageMatrix(Matrix m){
/** Matrix是否為空並是否定義 **/
if (m != null && m.isIdentity()) {
m = null;
}
if (m == null && !this.mMatrix.isIdentity() || m != null && !this.mMatrix.equals(m)) {
this.mMatrix.set(m);
invalidate();
}
}
static private void translatePoint(Matrix matrix, float [] xy) {
matrix.mapPoints(xy);
}
/**
* 設置Bitmap
*
* @param bitmap
*/
public void setImageBitmap(final Bitmap bitmap) {
final int viewWidth = getWidth();
// 開啟硬件加速
if( Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB && bitmap!=null && bitmap.getHeight()>1800 )
setLayerType(View.LAYER_TYPE_SOFTWARE, null);
if (viewWidth <= 0) {
mOnLayoutRunnable = new Runnable() {
public void run() {
setImageBitmap(bitmap);
}
};
return;
}
if (bitmap != null) {
setBaseMatrix(bitmap, mBaseMatrix);
this.mBitmap = bitmap;
} else {
mBaseMatrix.reset();
this.mBitmap = bitmap;
}
mSuppMatrix.reset();
setImageMatrix(getImageViewMatrix());
mMaxZoom = maxZoom();
zoomTo(zoomDefault());
}
public void zoomTo(float scale) {
float width = getWidth();
float height = getHeight();
zoomTo(scale, width/2F, height/2F);
}
protected void zoomTo(float scale, float centerX, float centerY) {
if (scale > mMaxZoom) {
scale = mMaxZoom;
}
float oldScale = getScale();
float deltaScale = scale / oldScale;
/** 根據某個中心點按照比例縮放 **/
mSuppMatrix.postScale(deltaScale, deltaScale, centerX, centerY);
setImageMatrix(getImageViewMatrix());
center(true, true, false);
}
/**
* 計算中心位置
*
* @param vertical
* @param horizontal
* @param animate
*/
protected void center(boolean vertical, boolean horizontal, boolean animate) {
if (mBitmap == null)
return;
Matrix m = getImageViewMatrix();
float [] topLeft = new float[] { 0, 0 };
float [] botRight = new float[] { mBitmap.getWidth(), mBitmap.getHeight() };
translatePoint(m, topLeft);
translatePoint(m, botRight);
float height = botRight[1] - topLeft[1];
float width = botRight[0] - topLeft[0];
float deltaX = 0, deltaY = 0;
if (vertical) {
int viewHeight = getHeight();
if (height < viewHeight) {
deltaY = (viewHeight - height)/2 - topLeft[1];
} else if (topLeft[1] > 0) {
deltaY = -topLeft[1];
} else if (botRight[1] < viewHeight) {
deltaY = getHeight() - botRight[1];
}
}
if (horizontal) {
int viewWidth = getWidth();
if (width < viewWidth) {
deltaX = (viewWidth - width)/2 - topLeft[0];
} else if (topLeft[0] > 0) {
deltaX = -topLeft[0];
} else if (botRight[0] < viewWidth) {
deltaX = viewWidth - botRight[0];
}
}
postTranslate(deltaX, deltaY);
if (animate) {
Animation a = new TranslateAnimation(-deltaX, 0, -deltaY, 0);
a.setStartTime(SystemClock.elapsedRealtime());
a.setDuration(250);
setAnimation(a);
}
setImageMatrix(getImageViewMatrix());
}
protected void postTranslate(float dx, float dy) {
mSuppMatrix.postTranslate(dx, dy);
}
public float getScale() {
return getScale(mSuppMatrix);
}
protected float getScale(Matrix matrix) {
if(mBitmap!=null)
return getValue(matrix, Matrix.MSCALE_X);
else
return 1f;
}
protected float getValue(Matrix matrix, int whichValue) {
matrix.getValues(mMatrixValues);
return mMatrixValues[whichValue];
}
/**
* 計算最大的拉伸比例
*
* @return
*/
protected float maxZoom() {
if (mBitmap == null)
return 1F;
float fw = (float) mBitmap.getWidth() / (float)mThisWidth;
float fh = (float) mBitmap.getHeight() / (float)mThisHeight;
float max = Math.max(fw, fh) * 16;
return max;
}
/**
* 原始顯示比例
*
* @return
*/
public float zoomDefault() {
if (mBitmap == null)
return 1F;
float fw = (float)mThisWidth/(float)mBitmap.getWidth();
float fh = (float)mThisHeight/(float)mBitmap.getHeight();
return Math.max(Math.min(fw, fh),1);
}
protected void zoomTo(final float scale, final float centerX, final float centerY, final float durationMs) {
final float incrementPerMs = (scale - getScale()) / durationMs;
final float oldScale = getScale();
final long startTime = System.currentTimeMillis();
post(new Runnable() {
public void run() {
long now = System.currentTimeMillis();
float currentMs = Math.min(durationMs, (float)(now - startTime));
float target = oldScale + (incrementPerMs * currentMs);
zoomTo(target, centerX, centerY);
if (currentMs < durationMs) {
post(this);
}
}
});
}
protected void scrollBy( float distanceX, float distanceY, final float durationMs ){
final float dx = distanceX;
final float dy = distanceY;
final long startTime = System.currentTimeMillis();
mFling = new Runnable() {
float old_x = 0;
float old_y = 0;
public void run()
{
long now = System.currentTimeMillis();
float currentMs = Math.min( durationMs, now - startTime );
float x = easeOut( currentMs, 0, dx, durationMs );
float y = easeOut( currentMs, 0, dy, durationMs );
postTranslate( ( x - old_x ), ( y - old_y ) );
center(true, true, false);
old_x = x;
old_y = y;
if ( currentMs < durationMs ) {
post( this );
}
}
};
post( mFling );
}
private float easeOut( float time, float start, float end, float duration){
return end * ( ( time = time / duration - 1 ) * time * time + 1 ) + start;
}
@Override
protected void onDraw(Canvas canvas) {
// TODO Auto-generated method stub
if(mBitmap!=null && !mBitmap.isRecycled() ){
if( Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB && getLayerType() == View.LAYER_TYPE_HARDWARE ){
canvas.drawBitmap(mBitmap, mMatrix, null);
}else{
if( (System.currentTimeMillis()-mLastDraw) > sPaintDelay ){
canvas.drawBitmap(mBitmap, mMatrix, mPaint);
mLastDraw = System.currentTimeMillis();
}
else{
canvas.drawBitmap(mBitmap, mMatrix, null);
removeCallbacks(mRefresh);
postDelayed(mRefresh, sPaintDelay);
}
}
}
}
/**
* @author Administrator
*
* 手勢縮放監聽
*/
class ScaleListener extends ScaleGestureDetector.SimpleOnScaleGestureListener {
@Override
public boolean onScale(ScaleGestureDetector detector) {
// TODO Auto-generated method stub
Log.i("ZoomImageView", "onScale");
if(detector!=null && detector.isInProgress()){
try{
float targetScale = getScale() * detector.getScaleFactor();
targetScale = Math.min(maxZoom(), Math.max(targetScale, 1.0f) );
zoomTo(targetScale, detector.getFocusX(), detector.getFocusY() );
invalidate();
return true;
}catch(IllegalArgumentException e){
e.printStackTrace();
}
}
return false;
}
};
/**
* @author Administrator
*
* 手勢識別監聽
*/
class MyGestureListener extends GestureDetector.SimpleOnGestureListener {
@Override
public boolean onScroll(MotionEvent e1, MotionEvent e2,
float distanceX, float distanceY) {
// TODO Auto-generated method stub
Log.i("ZoomImageView", "onScroll");
if((e1 != null && e1.getPointerCount() > 1) || (e2 != null && e2.getPointerCount() > 1)
|| (mScaleDetector != null && mScaleDetector.isInProgress())){
return false;
}
if(getScale() > zoomDefault() ) {
removeCallbacks(mFling);
postTranslate(-distanceX, -distanceY);
center(true, true, false);
}
return true;
}
@Override
public boolean onFling(MotionEvent e1, MotionEvent e2, float velocityX,
float velocityY) {
Log.i("ZoomImageView", "onFling");
// TODO Auto-generated method stub
if ((e1!=null && e1.getPointerCount() > 1) || ( e2!=null && e2.getPointerCount() > 1))
return false;
if (mScaleDetector.isInProgress())
return false;
try{
float diffX = e2.getX() - e1.getX();
float diffY = e2.getY() - e1.getY();
if ( Math.abs( velocityX ) > 800 || Math.abs( velocityY ) > 800 ) {
scrollBy( diffX / 2, diffY / 2, 300 );
invalidate();
}
}catch(NullPointerException e){
e.printStackTrace();
}
return super.onFling( e1, e2, velocityX, velocityY );
}
@Override
public boolean onDoubleTap(MotionEvent e) {
// TODO Auto-generated method stub
Log.i("ZoomImageView", "onDoubleTap");
if ( getScale() > zoomDefault() ){
zoomTo(zoomDefault());
}
else
zoomTo(zoomDefault()*3, e.getX(), e.getY(),200);
return true;
}
@Override
public boolean onSingleTapConfirmed(MotionEvent e) {
// TODO Auto-generated method stub
Log.i("ZoomImageView", "onSingleTapConfirmed");
// 設置點擊事件
if(mImageTouchedListener != null) {
mImageTouchedListener.onImageTouched();
return false;
}
return super.onSingleTapConfirmed(e);
}
}
@Override
public boolean onTouchEvent(MotionEvent event) {
// TODO Auto-generated method stub
if(mBitmap != null) {
mScaleDetector.onTouchEvent(event);
if(!mScaleDetector.isInProgress()) {
mGestureDetector.onTouchEvent(event);
}
}
return true;
};
/**
*
* @author Administrator
*
* 點擊接口
*/
private onImageTouchedListener mImageTouchedListener;
public interface onImageTouchedListener {
void onImageTouched();
}
public void setOnImageTouchedListener(onImageTouchedListener listener ){
this.mImageTouchedListener = listener;
}
xml布局:
復制代碼 代碼如下:
<com.example.pay.ZoomImageView
android:scaleType="matrix"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:id="@+id/zommImageView"
/>
activity調用方法:
復制代碼 代碼如下:
mZoomImageView = (ZoomImageView) findViewById(R.id.zommImageView);
mZoomImageView.setImageBitmap(BitmapFactory.decodeResource(getResources(), R.drawable.ic_launcher));
mZoomImageView.setOnImageTouchedListener(new onImageTouchedListener() {
@Override
public void onImageTouched() {
// TODO Auto-generated method stub
Toast.makeText(MainActivity.this, "11111", Toast.LENGTH_LONG).show();
}
});
主活動的布局文件 activity_main.xml android:layout_width=fill_parent and
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