android webview js交互， 响应webview中的图片点击事件 ,点击（双击）使图片变大，单击退出
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最近碰到个新需求需要点击webview中的图片进行放大显示。
整理了下思路，想到了下面的一个可行的方案。
http://download.csdn.net/detail/zlb_lover/9654404 代码下载地址
http://download.csdn.net/detail/zlb_lover/9654404 代码下载地址
方案思路，
1.在点击图片的时候调用本地的java方法并给出响应的图片地址
2.本地获得图片地址后，开启一个遮罩activity进行显示和处理
第二步的实现很容易实现，关键是第一步的实现，在网页中点击图片不会调用本地的java代码。那么我们需要给这个点击事件加上相应的js函数，让点击事件调用的js函数来调用我们提前准备好的java函数，等我们捕获到图片的url剩下的就好处理了。
关键点就是给普通的html注入我们的js函数，让图片能够响应点击并调用js函数，在通过js函数来调用我们的java函数。听起来好像有点绕，不过也不难，下面我们用代码实现下
1。加载webview的MainActivity.java代码
（1）activity_main.xml
5、在AndroidMainfest.xml中注册，和添加权限
这次实例的主要功能：点击图片在新的activity中展示，对图片能够进行手势操作，包括双指缩放等
效果图
1。加载webview的MainActivity.java代码
package wst.webview;import android.annotation.SuppressLint;import android.app.Activity;import android.content.Context;import android.content.Intent;import android.graphics.Bitmap;import android.os.Bundle;import android.webkit.WebView;import android.webkit.WebViewClient;@SuppressLint("SetJavaScriptEnabled")public class MainActivity extends Activity { /** * * 最近碰到个新需求需要点击webview中的图片进行放大显示。 整理了下思路，想到了下面的一个可行的方案。 方案思路， 1.在点击图片的时候调用本地的java方法并给出响应的图片地址 2.本地获得图片地址后，开启一个遮罩activity进行显示和处理 第二步的实现很容易实现，关键是第一步的实现，在网页中点击图片不会调用本地的java代码。那么我们需要给这个点击事件加上相应的js函数，让点击事件调用的js函数来调用我们提前准备好的java函数，等我们捕获到图片的url剩下的就好处理了。 关键点就是给普通的html注入我们的js函数，让图片能够响应点击并调用js函数，在通过js函数来调用我们的java函数。听起来好像有点绕，不过也不难，下面我们用代码实现下 *///加载webview的activity代码 private WebView contentWebView = null; @SuppressLint("SetJavaScriptEnabled") @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); contentWebView = (WebView) findViewById(R.id.webview); //启用javascript contentWebView.getSettings().setJavaScriptEnabled(true); //这个使我项目的webview的js语法代码。 String ui="<head>\n" + " <style>\n" + " .center_image { width: 100%}\n" + " .hide_image { display: none}\n" + " </style>\n" + " </head><img class='center_image' src='https://img.alicdn.com/imgextra/i4/656010309/TB2OYr1uXXXXXb3XpXXXXXXXXXX_!!656010309.jpg'><img class='center_image' src='https://img.alicdn.com/imgextra/i2/656010309/TB208UcuXXXXXadXpXXXXXXXXXX_!!656010309.jpg'><img class='center_image' src='https://img.alicdn.com/imgextra/i4/656010309/TB20iQsuXXXXXa_XXXXXXXXXXXX_!!656010309.jpg'><img class='center_image' src='https://img.alicdn.com/imgextra/i2/656010309/TB2I8UquXXXXXbZXXXXXXXXXXXX_!!656010309.jpg'><img class='center_image' src='https://img.alicdn.com/imgextra/i4/656010309/TB2nrgAuXXXXXanXXXXXXXXXXXX_!!656010309.jpg'><img class='center_image' src='https://img.alicdn.com/imgextra/i1/656010309/TB2DTMCuXXXXXXZXXXXXXXXXXXX_!!656010309.jpg'><img class='center_image' src='https://img.alicdn.com/imgextra/i2/656010309/TB2B3Y1uXXXXXcjXpXXXXXXXXXX_!!656010309.jpg'><img class='center_image' src='https://img.alicdn.com/imgextra/i3/656010309/TB2KjAguXXXXXXMXpXXXXXXXXXX_!!656010309.jpg'><img class='center_image' src='https://img.alicdn.com/imgextra/i4/656010309/TB2fshcXb75VKBjy0FcXXbAkXXa_!!656010309.jpg'><script>\n" + " var imgs = document.getElementsByClassName('center_image');\n" + " for (var i = 0; i < imgs.length; i++) {\n" + " imgs[i]['index']=i;\n" + " imgs[i].addEventListener('load', function() {\n" + " if (imgs[this.index].naturalWidth < 100) {\n" + " this.className += ' hide_image';\n" + " }\n" + " });\n" + " imgs[i].addEventListener('error', function() {\n" + " this.className += ' hide_image';\n" + " });\n" + " }\n" + " </script>"; //给webView添加js代码 contentWebView.loadData(ui,"text/html","utf-8"); // 添加js交互接口类，并起别名 imagelistner addJavaScriptInterface方式帮助我们从一个网页传递值到Android XML视图（反之亦然）。 contentWebView.addJavascriptInterface(new JavascriptInterface(this), "imagelistner"); contentWebView.setWebViewClient(new MyWebViewClient()); } // 注入js函数监听 private void addImageClickListner() { // 这段js函数的功能就是，遍历所有的img，并添加onclick函数，函数的功能是在图片点击的时候调用本地java接口并传递url过去 contentWebView.loadUrl("javascript:(function(){" + "var objs = document.getElementsByTagName(\"img\"); " + "for(var i=0;i<objs.length;i++) " + "{" + " objs[i].onclick=function() " + " { " + " window.imagelistner.openImage(this.src); " + " } " + "}" + "})()"); } // js通信接口 public class JavascriptInterface { private Context context; public JavascriptInterface(Context context) { this.context = context; } public void openImage(String img) { System.out.println(img); Intent intent = new Intent(); intent.putExtra("image", img); intent.setClass(context, ShowWebImageActivity.class); context.startActivity(intent); System.out.println(img); } } private class MyWebViewClient extends WebViewClient { //在点击请求的是链接是才会调用，重写此方法返回true表明点击网页里面的链接还是在当前的webview里跳转，不跳到浏览器那边。 @Override public boolean shouldOverrideUrlLoading(WebView view, String url) { return super.shouldOverrideUrlLoading(view, url); } //在页面加载结束时调用。 @Override public void onPageFinished(WebView view, String url) { view.getSettings().setJavaScriptEnabled(true); super.onPageFinished(view, url); // html加载完成之后，添加监听图片的点击js函数 addImageClickListner(); } //在页面加载开始时调用。 @Override public void onPageStarted(WebView view, String url, Bitmap favicon) { view.getSettings().setJavaScriptEnabled(true); super.onPageStarted(view, url, favicon); } @Override public void onReceivedError(WebView view, int errorCode, String description, String failingUrl) { super.onReceivedError(view, errorCode, description, failingUrl); } }}2、展示图片的ShowWebImage.java代码
package wst.webview;import android.app.Activity;import android.graphics.drawable.BitmapDrawable;import android.graphics.drawable.Drawable;import android.os.Bundle;import android.util.Log;import android.widget.TextView;import java.io.IOException;import java.io.InputStream;import java.net.URL;public class ShowWebImageActivity extends Activity { /** * 在一个activity中销毁指定activity */ public static ShowWebImageActivity showWebImageActivity; private TextView imageTextView = null; private String imagePath = null; private ZoomableImageView imageView = null; @Override protected void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); showWebImageActivity=this; setContentView(R.layout.show_webimage); this.imagePath = getIntent().getStringExtra("image"); /*this.imageTextView = (TextView) findViewById(R.id.show_webimage_imagepath_textview); imageTextView.setText(this.imagePath);*/ imageView = (ZoomableImageView) findViewById(R.id.show_webimage_imageview); try { imageView.setImageBitmap(((BitmapDrawable) ShowWebImageActivity.loadImageFromUrl(this.imagePath)).getBitmap()); } catch (IOException e) { e.printStackTrace(); } } public static Drawable loadImageFromUrl(String url) throws IOException { URL m = new URL(url); InputStream i = (InputStream) m.getContent(); Drawable d = Drawable.createFromStream(i, "src"); return d; } @Override protected void onDestroy() { super.onDestroy(); Log.i("zlb","zlb==="); }}3、自定义的ZooMableImageView.java类，
package wst.webview;/* * * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. *//* * This class is based upon the file ImageViewTouchBase.java which can be found at: * https://dl-ssl.google.com/dl/googlesource/git-repo/repo * * Copyright (C) 2009 The Android Open Source Project */import android.annotation.SuppressLint;import android.content.Context;import android.graphics.Bitmap;import android.graphics.Canvas;import android.graphics.Matrix;import android.graphics.Paint;import android.os.Build;import android.os.SystemClock;import android.util.AttributeSet;import android.view.GestureDetector;import android.view.MotionEvent;import android.view.ScaleGestureDetector;import android.view.View;import android.view.animation.Animation;import android.view.animation.TranslateAnimation;//写一个类继承View实现图片的放大，和缩放。@SuppressLint("NewApi")public class ZoomableImageView extends View { // Statics static final float sPanRate = 7; static final float sScaleRate = 1.25F; static final int sPaintDelay = 250; static final int sAnimationDelay = 500; // This is the base transformation which is used to show the image // initially. The current computation for this shows the image in // it's entirety, letterboxing as needed. One could chose to // show the image as cropped instead. // // This matrix is recomputed when we go from the thumbnail image to // the full size image. private Matrix mBaseMatrix = new Matrix(); // This is the supplementary transformation which reflects what // the user has done in terms of zooming and panning. // // This matrix remains the same when we go from the thumbnail image // to the full size image. private Matrix mSuppMatrix = new Matrix(); // This is the final matrix which is computed as the concatentation // of the base matrix and the supplementary matrix. private Matrix mDisplayMatrix = new Matrix(); // A replacement ImageView matrix private Matrix mMatrix = new Matrix(); // Used to filter the bitmaps when hardware acceleration is not enabled private Paint mPaint; // Temporary buffer used for getting the values out of a matrix. private float[] mMatrixValues = new float[9]; // The current bitmap being displayed. private Bitmap mBitmap; // Dimensions for the view private int mThisWidth = -1, mThisHeight = -1; // The max zoom for the view, determined programatically private float mMaxZoom; // If not null, calls setImageBitmap when onLayout is triggered private Runnable mOnLayoutRunnable = null; // Stacked to the internal queue to invalidate the view private Runnable mRefresh = null; // Stacked to the internal queue to scroll the view private Runnable mFling = null; // The time of the last draw operation private double mLastDraw = 0; // Scale and gesture listeners for the view private ScaleGestureDetector mScaleDetector; private GestureDetector mGestureDetector; // Programatic entry point public ZoomableImageView(Context context) { super(context); init( context ); } // XML entry point public ZoomableImageView(Context context, AttributeSet attrs) { super(context, attrs); init( context ); } // Setup the view private void init( Context context) { mPaint = new Paint(); mPaint.setDither(true); mPaint.setFilterBitmap(true); mPaint.setAntiAlias(true); // Setup the refresh runnable mRefresh = new Runnable() { @Override public void run() { postInvalidate(); } }; // Setup the gesture and scale listeners mScaleDetector = new ScaleGestureDetector( context, new ScaleListener() ); mGestureDetector = new GestureDetector(context, new MyGestureListener()); // Force hardware acceleration if( Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB ) setLayerType(View.LAYER_TYPE_HARDWARE, null); } // Get the bitmap for the view public Bitmap getImageBitmap(){ return mBitmap; } // Free the bitmaps and matrices public void clear(){ if(mBitmap!=null) mBitmap = null; } // When the layout is calculated, set the @Override protected void onLayout(boolean changed, int left, int top, int right, int bottom) { 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()); } } // Translate a given point through a given matrix. static private void translatePoint(Matrix matrix, float [] xy) { matrix.mapPoints(xy); } // Identical to the setImageMatrix method in ImageView public void setImageMatrix(Matrix m){ if (m != null && m.isIdentity()) { m = null; } // don't invalidate unless we're actually changing our matrix if (m == null && !this.mMatrix.isIdentity() || m != null && !this.mMatrix.equals(m)) { this.mMatrix.set(m); invalidate(); } } // Sets the bitmap for the image and resets the base public void setImageBitmap(final Bitmap bitmap) { final int viewWidth = getWidth(); 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(); // Set the image to fit the screen zoomTo(zoomDefault()); } // Unchanged from ImageViewTouchBase // Center as much as possible in one or both axis. Centering is // defined as follows: if the image is scaled down below the // view's dimensions then center it (literally). If the image // is scaled larger than the view and is translated out of view // then translate it back into view (i.e. eliminate black bars). 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()); } // Unchanged from ImageViewTouchBase protected float getValue(Matrix matrix, int whichValue) { matrix.getValues(mMatrixValues); return mMatrixValues[whichValue]; } // Get the scale factor out of the matrix. protected float getScale(Matrix matrix) { // If the bitmap is set return the scale if(mBitmap!=null) return getValue(matrix, Matrix.MSCALE_X); // Otherwise return the default value of 1 else return 1f; } // Returns the current scale of the view public float getScale() { return getScale(mSuppMatrix); } // Setup the base matrix so that the image is centered and scaled properly. 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; } matrix.setScale(scale, scale); matrix.postTranslate( (viewWidth - ((float)bitmap.getWidth() * scale))/2F, (viewHeight - ((float)bitmap.getHeight() * scale))/2F); } // Combine the base matrix and the supp matrix to make the final matrix. protected Matrix getImageViewMatrix() { mDisplayMatrix.set(mBaseMatrix); mDisplayMatrix.postConcat(mSuppMatrix); return mDisplayMatrix; } // Sets the maximum zoom, which is a scale relative to the base matrix. It is calculated to show // the image at 400% zoom regardless of screen or image orientation. If in the future we decode // the full 3 megapixel image, rather than the current 1024x768, this should be changed down to // 200%. 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; } // Tries to make best use of the space by zooming the picture 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); } // Unchanged from ImageViewTouchBase protected void zoomTo(float scale, float centerX, float centerY) { if (scale > mMaxZoom) { scale = mMaxZoom; } float oldScale = getScale(); float deltaScale = scale / oldScale; mSuppMatrix.postScale(deltaScale, deltaScale, centerX, centerY); setImageMatrix(getImageViewMatrix()); center(true, true, false); } // Unchanged from ImageViewTouchBase 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(); // Setup the zoom runnable 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); } } }); } // Unchanged from ImageViewTouchBase public void zoomTo(float scale) { float width = getWidth(); float height = getHeight(); zoomTo(scale, width/2F, height/2F); } // Unchanged from ImageViewTouchBase protected void zoomIn() { zoomIn(sScaleRate); } // Unchanged from ImageViewTouchBase protected void zoomOut() { zoomOut(sScaleRate); } // Unchanged from ImageViewTouchBase protected void zoomIn(float rate) { if (getScale() >= mMaxZoom) { return; // Don't let the user zoom into the molecular level. } if (mBitmap == null) { return; } float width = getWidth(); float height = getHeight(); mSuppMatrix.postScale(rate, rate, width/2F, height/2F); setImageMatrix(getImageViewMatrix()); } // Unchanged from ImageViewTouchBase protected void zoomOut(float rate) { if (mBitmap == null) { return; } float width = getWidth(); float height = getHeight(); Matrix tmp = new Matrix(mSuppMatrix); tmp.postScale(1F/sScaleRate, 1F/sScaleRate, width/2F, height/2F); if (getScale(tmp) < 1F) { mSuppMatrix.setScale(1F, 1F, width/2F, height/2F); } else { mSuppMatrix.postScale(1F/rate, 1F/rate, width/2F, height/2F); } setImageMatrix(getImageViewMatrix()); center(true, true, false); } // Unchanged from ImageViewTouchBase protected void postTranslate(float dx, float dy) { mSuppMatrix.postTranslate(dx, dy); } // Fling a view by a distance over time 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 ); } // Gradually slows down a fling velocity private float easeOut( float time, float start, float end, float duration){ return end * ( ( time = time / duration - 1 ) * time * time + 1 ) + start; } // Custom draw operation to draw the bitmap using mMatrix @Override protected void onDraw(Canvas canvas) { // Check if the bitmap was ever set if(mBitmap!=null && !mBitmap.isRecycled() ){ // If the current version is above Gingerbread and the layer type is // hardware accelerated, the paint is no longer needed if( Build.VERSION.SDK_INT >= Build.VERSION_CODES.HONEYCOMB && getLayerType() == View.LAYER_TYPE_HARDWARE ){ canvas.drawBitmap(mBitmap, mMatrix, null); }else{ // Check if the time between draws has been met and draw the bitmap if( (System.currentTimeMillis()-mLastDraw) > sPaintDelay ){ canvas.drawBitmap(mBitmap, mMatrix, mPaint); mLastDraw = System.currentTimeMillis(); } // Otherwise draw the bitmap without the paint and resubmit a new request else{ canvas.drawBitmap(mBitmap, mMatrix, null); removeCallbacks(mRefresh); postDelayed(mRefresh, sPaintDelay); } } } } // Adjusts the zoom of the view class ScaleListener extends ScaleGestureDetector.SimpleOnScaleGestureListener { @Override public boolean onScale( ScaleGestureDetector detector ) { // Check if the detector is in progress in order to proceed if(detector!=null && detector.isInProgress() ){ try{ // Grab the scale float targetScale = getScale() * detector.getScaleFactor(); // Correct for the min scale targetScale = Math.min( maxZoom(), Math.max( targetScale, 1.0f) ); // Zoom and invalidate the view zoomTo( targetScale, detector.getFocusX(), detector.getFocusY() ); invalidate(); return true; }catch(IllegalArgumentException e){ e.printStackTrace(); } } return false; } } // Handles taps and scrolls of the view private class MyGestureListener extends GestureDetector.SimpleOnGestureListener { /** * 对WebView的图片进行单击，以/单击退出ShowWebImageActiviyt,回到架子WebView所在的MainActivity。 */ @Override public boolean onSingleTapConfirmed(MotionEvent e) { //单击退出ShowWebImageActiviyt,回到架子WebView所在的MainActivity。 ShowWebImageActivity.showWebImageActivity.finish(); return true; } @Override public boolean onScroll(MotionEvent e1, MotionEvent e2, float distanceX, float distanceY) { // Skip if there are multiple points of contact if ( (e1!=null&&e1.getPointerCount() > 1) || (e2!=null&&e2.getPointerCount() > 1) || (mScaleDetector!=null && mScaleDetector.isInProgress()) ) return false; // Scroll the bitmap if ( getScale() > zoomDefault() ) { removeCallbacks(mFling); postTranslate(-distanceX, -distanceY); center(true, true, false); } // Default case return true; } /** * 对webView的图片进行双击，时图片放大，如果图片已经放大，再进行双击时，图片缩小为原状。 */ @Override public boolean onDoubleTap(MotionEvent e) { // If the zoom is over 1x, reset to 1x if ( getScale() > zoomDefault() ){ zoomTo(zoomDefault()); } // If the zoom is default, zoom into 2x else zoomTo(zoomDefault()*3, e.getX(), e.getY(),200); // Always true as double tap was performed return true; } @Override public boolean onFling( MotionEvent e1, MotionEvent e2, float velocityX, float velocityY ) { 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){ } return super.onFling( e1, e2, velocityX, velocityY ); } } @Override public boolean onTouchEvent(MotionEvent event) { // If the bitmap was set, check the scale and gesture detectors if(mBitmap!=null){ // Check the scale detector mScaleDetector.onTouchEvent( event ); // Check the gesture detector if(!mScaleDetector.isInProgress()) mGestureDetector.onTouchEvent( event ); } // Default case return true; }}4，布局文件（两个）
（1）activity_main.xml
<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical" > <WebView android:id="@+id/webview" android:layout_width="fill_parent" android:layout_height="fill_parent" android:layout_weight="9" /></LinearLayout>(2)showimageweb.xml
<?xml version="1.0" encoding="utf-8"?><LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" android:layout_width="fill_parent" android:layout_height="fill_parent" android:orientation="vertical" > <!-- TODO 默认占位图 --> <wst.webview.ZoomableImageView android:id="@+id/show_webimage_imageview" android:layout_width="fill_parent" android:layout_height="fill_parent" android:scaleType="matrix" android:src="@drawable/icon" /> <TextView android:id="@+id/show_webimage_imagepath_textview" android:layout_width="fill_parent" android:layout_height="wrap_content" android:gravity="center" android:textColor="#ffff0000" /></LinearLayout>
5、在AndroidMainfest.xml中注册，和添加权限
<?xml version="1.0" encoding="utf-8"?><manifest xmlns:android="http://schemas.android.com/apk/res/android" package="wst.webview" android:versionCode="1" android:versionName="1.0" > <application android:icon="@drawable/icon" android:label="@string/app_name" > <activity android:name="wst.webview.MainActivity" android:label="@string/app_name" > <intent-filter> <action android:name="android.intent.action.MAIN" /> <category android:name="android.intent.category.LAUNCHER" /> </intent-filter> </activity> <activity android:name=".ShowWebImageActivity" android:configChanges="orientation" android:label="@string/app_name" android:screenOrientation="portrait" android:theme="@style/Transparent" > </activity> </application> <uses-permission android:name="android.permission.INTERNET" /></manifest>
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- android webview js交互， 响应webview中的图片点击事件 ,点击（双击）使图片变大，单击退出
- android webview js交互， 响应webview中的图片点击事件
- android webview js交互， 响应webview中的图片点击事件
- android webview js交互， 响应webview中的图片点击事件
- android webview js交互， 响应webview中的图片点击事件
- android webview js交互， 响应webview中的图片点击事件
- android webview js交互， 响应webview中的图片点击事件
- android webview js交互， 响应webview中的图片点击事件
- android webview js交互， 响应webview中的图片点击事件
- android webview js交互， 响应webview中的图片点击事件
- android webview js交互， 响应webview中的图片点击事件 .
- android webview js交互， 响应webview中的图片点击事件
- android webview js交互， 响应webview中的图片点击事件
- android webview js交互， 响应webview中的图片点击事件
- android webview js交互， 响应webview中的图片点击事件
- android webview js交互， 响应webview中的图片点击事件
- 响应webview中的图片点击事件 （android webview js交互）
- Android WebView JS交互之响应WebView中的图片点击事件
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- android webview js交互， 响应webview中的图片点击事件 ,点击（双击）使图片变大，单击退出
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