GridView+pagerViewer 图片浏览，点击全屏，滑动左右切换+删除关闭+拍照

于 2014-07-23 07:46:08 发布
阅读量2k 收藏 2
点赞数
CC 4.0 BY-SA版权
文章标签： 安卓 android
版权声明：本文为博主原创文章，遵循 CC 4.0 BY-SA 版权协议，转载请附上原文出处链接和本声明。
本文链接：https://blog.youkuaiyun.com/lu161513/article/details/38056905
本文介绍了一款基于Android平台的图片浏览与拍摄应用，包括图片浏览、全屏查看及拍照功能实现。应用采用多Activity与自定义Adapter进行交互，支持手势缩放功能，实现了流畅的用户体验。

摘要生成于 C知道 ，由 DeepSeek-R1 满血版支持， 前往体验 >

包结构


BrowsePicActivity.java

package com.example.activity;

import java.io.File;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import com.example.adapter.GridViewImageAdapter;
import com.example.captureimage.R;
import com.example.captureimage.R.layout;
import com.example.help.AppConstant;
import com.example.help.Utils;

import android.R.integer;
import android.app.Activity;
import android.content.Context;
import android.content.Intent;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.BitmapDrawable;
import android.net.Uri;
import android.os.Bundle;
import android.util.TypedValue;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemClickListener;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageSwitcher;
import android.widget.ImageView;
import android.widget.SimpleAdapter;
import android.widget.TableLayout;
import android.widget.TableRow;
import android.widget.Toast;

public class BrowsePicActivity extends Activity {
	private Utils utils;
	private GridView gridView;
	private ArrayList<String> fileNames=new ArrayList<String>();
	private GridViewImageAdapter adapter;
	private int columnWidth;


	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_browse_pic);
		
		gridView=(GridView) findViewById(R.id.grid_view);
		utils=new Utils(this);
		initGridLayout();
		
		fileNames=utils.getFilePaths();
		adapter=new GridViewImageAdapter(BrowsePicActivity.this, fileNames, columnWidth);
		gridView.setAdapter(adapter);
		
		gridView.setOnItemClickListener(new OnItemClickListener() {

			@Override
			public void onItemClick(AdapterView<?> parent, View view,
					int position, long id) {
				// TODO Auto-generated method stub
				
			}
		});
		
		
	}
	
	@Override
	protected void onActivityResult(int requestCode, int resultCode, Intent data) {
		if(resultCode==100){
			this.recreate();
		}
	}


	private void initGridLayout() {
		Resources resources=getResources();
		float padding = TypedValue.applyDimension(TypedValue.COMPLEX_UNIT_DIP,
                AppConstant.GRID_PADDING, resources.getDisplayMetrics());
 
        columnWidth = (int) ((utils.getScreenWidth() - ((AppConstant.NUM_OF_COLUMNS + 1) * padding)) / AppConstant.NUM_OF_COLUMNS);
        
        gridView.setNumColumns(AppConstant.NUM_OF_COLUMNS);
        gridView.setColumnWidth(columnWidth);
        gridView.setStretchMode(GridView.NO_STRETCH);
        gridView.setPadding((int)padding,(int) padding,(int) padding,(int) padding);
        gridView.setHorizontalSpacing((int) padding);
        gridView.setVerticalSpacing((int) padding);
	}

	
}
CapturePicActivity.java 

package com.example.activity;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.lang.reflect.Field;

import com.example.captureimage.R;

import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.DialogInterface.OnClickListener;
import android.graphics.Bitmap;
import android.graphics.Bitmap.CompressFormat;
import android.graphics.BitmapFactory;
import android.graphics.ImageFormat;
import android.graphics.Matrix;
import android.hardware.Camera;
import android.hardware.Camera.AutoFocusCallback;
import android.hardware.Camera.PictureCallback;
import android.hardware.Camera.ShutterCallback;
import android.media.Image;
import android.os.Bundle;
import android.os.Environment;
import android.util.DisplayMetrics;
import android.view.Display;
import android.view.SurfaceHolder;
import android.view.SurfaceHolder.Callback;
import android.view.SurfaceView;
import android.view.View;
import android.view.Window;
import android.view.WindowManager;
import android.widget.EditText;
import android.widget.ImageButton;
import android.widget.ImageView;
import android.widget.Toast;

public class CapturePicActivity extends Activity {
	SurfaceView sView;
	SurfaceHolder surfaceHolder;
	int screenWidth, screenHeight;
	// 定义系统所用的照相机
	Camera camera;
	// 是否在预览中
	boolean isPreview = false;

	@Override
	public void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		// 设置全屏
		// requestWindowFeature(Window.FEATURE_NO_TITLE);
		// getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
		// WindowManager.LayoutParams.FLAG_FULLSCREEN);
		setContentView(R.layout.main);
		// 获取窗口管理器
		WindowManager wm = getWindowManager();
		Display display = wm.getDefaultDisplay();
		DisplayMetrics metrics = new DisplayMetrics();
		// 获取屏幕的宽和高
		display.getMetrics(metrics);
		screenWidth = metrics.widthPixels;
		screenHeight = metrics.heightPixels;
		// 获取界面中SurfaceView组件
		sView = (SurfaceView) findViewById(R.id.sView);
		// 设置该Surface不需要自己维护缓冲区
		sView.getHolder().setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS);
		// 获得SurfaceView的SurfaceHolder
		surfaceHolder = sView.getHolder();
		// 为surfaceHolder添加一个回调监听器
		surfaceHolder.addCallback(new Callback() {
			@Override
			public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
			}

			@Override
			public void surfaceCreated(SurfaceHolder holder) {
				// 打开摄像头
				initCamera();
			}

			@Override
			public void surfaceDestroyed(SurfaceHolder holder) {
				// 如果camera不为null ,释放摄像头
				if (camera != null) {
					if (isPreview)
						camera.stopPreview();
					camera.release();
					camera = null;
				}
			}
		});

	}

	private void initCamera() {
		if (!isPreview) {
			// 此处默认打开后置摄像头。
			// 通过传入参数可以打开前置摄像头
			camera = Camera.open(0); // ①
			camera.setDisplayOrientation(90);
		}
		if (camera != null && !isPreview) {
			try {
				Camera.Parameters parameters = camera.getParameters();
				// 设置预览照片的大小
				parameters.setPreviewSize(screenWidth, screenHeight);
				// 设置预览照片时每秒显示多少帧的最小值和最大值
				parameters.setPreviewFpsRange(4, 10);
				// 设置图片格式
				parameters.setPictureFormat(ImageFormat.JPEG);
				// 设置JPG照片的质量
				parameters.set("jpeg-quality", 85);
				// 设置照片的大小
				parameters.setPictureSize(screenWidth, screenHeight);
				// 通过SurfaceView显示取景画面
				camera.setPreviewDisplay(surfaceHolder); // ②
				// 开始预览
				camera.startPreview(); // ③
			} catch (Exception e) {
				e.printStackTrace();
			}
			isPreview = true;
		}
	}

	public void capture(View source) {
		if (camera != null) {
			// 控制摄像头自动对焦后才拍照
			camera.autoFocus(autoFocusCallback); // ④
		}
	}

	AutoFocusCallback autoFocusCallback = new AutoFocusCallback() {
		// 当自动对焦时激发该方法
		@Override
		public void onAutoFocus(boolean success, Camera camera) {
			if (success) {
				// takePicture()方法需要传入3个监听器参数
				// 第1个监听器：当用户按下快门时激发该监听器
				// 第2个监听器：当相机获取原始照片时激发该监听器
				// 第3个监听器：当相机获取JPG照片时激发该监听器
				camera.takePicture(new ShutterCallback() {
					public void onShutter() {
						// 按下快门瞬间会执行此处代码
					}
				}, new PictureCallback() {
					public void onPictureTaken(byte[] data, Camera c) {
						// 此处代码可以决定是否需要保存原始照片信息
					}
				}, myJpegCallback); // ⑤
			}
		}
	};

	PictureCallback myJpegCallback = new PictureCallback() {
		private Bitmap bm;

		@Override
		public void onPictureTaken(byte[] data, Camera camera) {
			// 根据拍照所得的数据创建位图
			bm = BitmapFactory.decodeByteArray(data, 0, data.length);
			Matrix matrix = new Matrix();
			matrix.setRotate(90, bm.getWidth() / 2, bm.getHeight() / 2);
			bm = Bitmap.createBitmap(bm, 0, 0, bm.getWidth(), bm.getHeight(), matrix, true);

			// 加载/layout/save.xml文件对应的布局资源
			View saveDialog = getLayoutInflater().inflate(R.layout.save, null);
			final EditText photoName = (EditText) saveDialog.findViewById(R.id.phone_name);
			// 获取saveDialog对话框上的ImageView组件
			ImageView show = (ImageView) saveDialog.findViewById(R.id.show);
			// 显示刚刚拍得的照片
			show.setImageBitmap(bm);

			// 使用对话框显示saveDialog组件
			new AlertDialog.Builder(CapturePicActivity.this).setView(saveDialog).setPositiveButton("保存", new OnClickListener() {
				@Override
				public void onClick(DialogInterface dialog, int which) {
					if (photoName.length() < 1) {
						try {
							Toast.makeText(CapturePicActivity.this, "请输入文件名", Toast.LENGTH_SHORT).show();
							Field field = dialog.getClass().getSuperclass().getDeclaredField("mShowing");
							field.setAccessible(true);
							field.set(dialog, false);
							dialog.dismiss();
						} catch (NoSuchFieldException e) {
							// TODO Auto-generated catch block
							e.printStackTrace();
						} catch (IllegalAccessException e) {
							// TODO Auto-generated catch block
							e.printStackTrace();
						} catch (IllegalArgumentException e) {
							// TODO Auto-generated catch block
							e.printStackTrace();
						}
					} else {
						try {
							Field field = dialog.getClass().getSuperclass().getDeclaredField("mShowing");
							field.setAccessible(true);
							field.set(dialog, true);
							dialog.dismiss();
							String pathName = Environment.getExternalStorageDirectory() + "/FNST/";
							String fileName = photoName.getText().toString() + ".jpg";
							File path = new File(pathName);
							File file = new File(pathName + fileName);
							System.out.println(pathName + fileName);
							if (!path.exists()) {
								path.mkdir();
								Toast.makeText(getApplicationContext(), "创建目录", Toast.LENGTH_SHORT).show();

							}
							if (!file.exists()) {
								file.createNewFile();
							}

							FileOutputStream outStream = null;

							// 打开指定文件对应的输出流
							outStream = new FileOutputStream(file);
							// 把位图输出到指定文件中
							bm.compress(CompressFormat.JPEG, 100, outStream);
							outStream.close();
						} catch (NoSuchFieldException e) {
							// TODO Auto-generated catch block
							e.printStackTrace();
						} catch (IllegalAccessException e) {
							// TODO Auto-generated catch block
							e.printStackTrace();
						} catch (IllegalArgumentException e) {
							// TODO Auto-generated catch block
							e.printStackTrace();
						} catch (FileNotFoundException e) {
							// TODO Auto-generated catch block
							e.printStackTrace();
						} catch (IOException e) {
							// TODO Auto-generated catch block
							e.printStackTrace();
						}
					}
				}
			}).setNegativeButton("取消", null).show();
			// 重新浏览
			camera.stopPreview();
			camera.startPreview();
			isPreview = true;
		}
	};

	public void browse(View view) {
		Intent intent = new Intent(CapturePicActivity.this, BrowsePicActivity.class);
		startActivity(intent);
		isPreview = false;
	}
}
FullScreenViewActivity.java 

package com.example.activity;

import com.example.adapter.FullScreenImageAdapter;
import com.example.captureimage.R;
import com.example.help.Utils;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Adapter;

public class FullScreenViewActivity extends Activity {
	
	private Utils utils;
	private FullScreenImageAdapter adapter;
	private ViewPager viewPager;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_fullscreenview_pic);
		
		viewPager=(ViewPager) findViewById(R.id.pager);
		utils=new Utils(this);
		Intent intent=getIntent();
		int position=intent.getIntExtra("position", 0);
		
		adapter=new FullScreenImageAdapter(FullScreenViewActivity.this, utils.getFilePaths());
		viewPager.setAdapter(adapter);
		viewPager.setCurrentItem(position);
		
	}
}
FullScreenViewActivity.java 

package com.example.activity;

import com.example.adapter.FullScreenImageAdapter;
import com.example.captureimage.R;
import com.example.help.Utils;

import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.support.v4.view.ViewPager;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.Adapter;

public class FullScreenViewActivity extends Activity {
	
	private Utils utils;
	private FullScreenImageAdapter adapter;
	private ViewPager viewPager;

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_fullscreenview_pic);
		
		viewPager=(ViewPager) findViewById(R.id.pager);
		utils=new Utils(this);
		Intent intent=getIntent();
		int position=intent.getIntExtra("position", 0);
		
		adapter=new FullScreenImageAdapter(FullScreenViewActivity.this, utils.getFilePaths());
		viewPager.setAdapter(adapter);
		viewPager.setCurrentItem(position);
		
	}
}
FullScreenImageAdapter.java 

package com.example.adapter;

import java.io.File;
import java.util.ArrayList;

import com.example.captureimage.R;

import android.R.integer;
import android.app.Activity;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.BitmapFactory.Options;
import android.support.v4.view.PagerAdapter;
import android.support.v4.view.ViewPager;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.RelativeLayout;

public class FullScreenImageAdapter extends PagerAdapter {
	private Activity activity;
	private ArrayList<String> fileNames;
	private LayoutInflater inflater;

	public FullScreenImageAdapter(Activity activity, ArrayList<String> fileNames) {
		super();
		this.activity = activity;
		this.fileNames = fileNames;
	}

	@Override
	public int getCount() {
		// TODO Auto-generated method stub
		return fileNames.size();
	}

	@Override
	public boolean isViewFromObject(View view, Object object) {
		// TODO Auto-generated method stub
		return view == ((RelativeLayout) object);
	}

	@Override
	public Object instantiateItem(ViewGroup container, int position) {
		ImageView imageView;
		Button btnClose;
		Button btnDelete;
		final String fileName=fileNames.get(position);

		inflater = (LayoutInflater) activity
				.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
		View viewLayout = inflater.inflate(R.layout.fullscreen_image,
				container, false);
		imageView = (ImageView) viewLayout.findViewById(R.id.imgDisplay);
		btnClose = (Button) viewLayout.findViewById(R.id.btnClose);
		btnDelete=(Button) viewLayout.findViewById(R.id.btnDelete);
		
		BitmapFactory.Options options = new BitmapFactory.Options();
		options.inPreferredConfig = Bitmap.Config.ARGB_8888;
		Bitmap bitmap = BitmapFactory.decodeFile(fileName,options);
		imageView.setImageBitmap(bitmap);

		btnClose.setOnClickListener(new OnClickListener() {
			@Override
			public void onClick(View v) {
				activity.finish();
			}
		});
		
		btnDelete.setOnClickListener(new OnClickListener() {			
			@Override
			public void onClick(View v) {
				File file=new File(fileName);
				file.delete();
				activity.setResult(100);
				activity.finish();
			}
		});
		
		((ViewPager) container).addView(viewLayout);
		return viewLayout;
	}
	
	@Override
	public void destroyItem(ViewGroup container,int position,Object object){
		 ((ViewPager) container).removeView((RelativeLayout) object);
	}

}
GridViewImageAdapter.java 

package com.example.adapter;

import java.io.File;
import java.io.FileInputStream;
import java.util.ArrayList;

import com.example.activity.BrowsePicActivity;
import com.example.activity.FullScreenViewActivity;

import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;

public class GridViewImageAdapter extends BaseAdapter {
	private Activity activity;
	private ArrayList<String> filePaths=new ArrayList<String>();
	private int imageWidth;
	
	public GridViewImageAdapter(Activity activity,ArrayList<String> filePaths,int imageWidth) {
		this.activity=activity;
		this.filePaths=filePaths;
		this.imageWidth=imageWidth;
		}
	
	@Override
	public int getCount() {
		// TODO Auto-generated method stub
		return filePaths.size();
	}

	@Override
	public Object getItem(int position) {
		// TODO Auto-generated method stub
		return filePaths.get(position);
	}

	@Override
	public long getItemId(int position) {
		// TODO Auto-generated method stub
		return position;
	}

	@Override
	public View getView(int position, View convertView, ViewGroup parent) {
		ImageView imageView;
		if(convertView==null){
			imageView=new ImageView(activity);
		}else{
			imageView = (ImageView) convertView;
		}
		Bitmap image=decodeFile(filePaths.get(position),imageWidth,imageWidth);
		imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
		imageView.setLayoutParams(new GridView.LayoutParams(imageWidth,
                imageWidth));
        imageView.setImageBitmap(image);
		//imageView.setOnClickListener(new OnImageClickListener(position));
		
		return imageView;
	}
	
	/*class OnImageClickListener implements OnClickListener {
		int postion;
		
		public OnImageClickListener(int position) {
			this.postion=position;
		}

		@Override
		public void onClick(View v) {
			// on selecting grid view image
            // launch full screen activity
			Intent intent=new Intent(activity,FullScreenViewActivity.class);
			intent.putExtra("position", postion);
			activity.startActivity(intent);
			activity.startActivityForResult(intent, 100);
		}
		
	}*/
	
	/*
     * Resizing image size
     */

	private Bitmap decodeFile(String filePath, int WIDTH, int HEIGHT) {
		try {
			File f = new File(filePath);
			 
            BitmapFactory.Options o = new BitmapFactory.Options();
            o.inJustDecodeBounds = true;
            BitmapFactory.decodeStream(new FileInputStream(f), null, o);
 
            final int REQUIRED_WIDTH = WIDTH;
            final int REQUIRED_HIGHT = HEIGHT;
            int scale = 1;
            while (o.outWidth / scale / 2 >= REQUIRED_WIDTH
                    && o.outHeight / scale / 2 >= REQUIRED_HIGHT)
                scale *= 2;
 
            BitmapFactory.Options o2 = new BitmapFactory.Options();
            o2.inSampleSize = scale;
            return BitmapFactory.decodeStream(new FileInputStream(f), null, o2);
            
		} catch (Exception e) {
			// TODO: handle exception
		}
		
		return null;
	}

}
AppConstant.java 

package com.example.help;

import java.util.Arrays;
import java.util.List;

public class AppConstant {

	// Number of columns of Grid View
	public static final int NUM_OF_COLUMNS = 3;

	// Gridview image padding
	public static final int GRID_PADDING = 8; // in dp

	// SD card image directory
	public static final String PHOTO_ALBUM = "FNST";

	// supported file formats
	public static final List<String> FILE_EXTN = Arrays.asList("jpg", "jpeg",
			"png");
}
Utils.java 

package com.example.help;

import java.io.File;
import java.util.ArrayList;
import java.util.Locale;

import android.app.AlertDialog;
import android.content.Context;
import android.graphics.Point;
import android.view.Display;
import android.view.WindowManager;
import android.widget.Toast;

public class Utils {

	private Context _context;

	// constructor
	public Utils(Context context) {
		this._context = context;
	}

	/*
	 * Reading file paths from SDCard
	 */
	public ArrayList<String> getFilePaths() {
		ArrayList<String> filePaths = new ArrayList<String>();

		File directory = new File(
				android.os.Environment.getExternalStorageDirectory()
						+ File.separator + AppConstant.PHOTO_ALBUM);

		// check for directory
		if (directory.isDirectory()) {
			// getting list of file paths
			File[] listFiles = directory.listFiles();

			// Check for count
			if (listFiles.length > 0) {

				// loop through all files
				for (int i = 0; i < listFiles.length; i++) {

					// get file path
					String filePath = listFiles[i].getAbsolutePath();

					// check for supported file extension
					if (IsSupportedFile(filePath)) {
						// Add image path to array list
						filePaths.add(filePath);
					}
				}
			} else {
				// image directory is empty
				Toast.makeText(
						_context,
						AppConstant.PHOTO_ALBUM
								+ " is empty. Please load some images in it !",
						Toast.LENGTH_LONG).show();
			}

		} else {
			AlertDialog.Builder alert = new AlertDialog.Builder(_context);
			alert.setTitle("Error!");
			alert.setMessage(AppConstant.PHOTO_ALBUM
					+ " directory path is not valid! Please set the image directory name AppConstant.java class");
			alert.setPositiveButton("OK", null);
			alert.show();
		}

		return filePaths;
	}

	/*
	 * Check supported file extensions
	 * 
	 * @returns boolean
	 */
	private boolean IsSupportedFile(String filePath) {
		String ext = filePath.substring((filePath.lastIndexOf(".") + 1),
				filePath.length());

		if (AppConstant.FILE_EXTN
				.contains(ext.toLowerCase(Locale.getDefault())))
			return true;
		else
			return false;

	}

	/*
	 * getting screen width
	 */
	public int getScreenWidth() {
		int columnWidth;
		WindowManager wm = (WindowManager) _context
				.getSystemService(Context.WINDOW_SERVICE);
		Display display = wm.getDefaultDisplay();

		final Point point = new Point();
		try {
			display.getSize(point);
			
		} catch (java.lang.NoSuchMethodError ignore) { // Older device
			point.x = display.getWidth();
			point.y = display.getHeight();
		}
		columnWidth = point.x;
		return columnWidth;
	}
}
button_background.xml 

<?xml version="1.0" encoding="utf-8"?>
<shape xmlns:android="http://schemas.android.com/apk/res/android"
    android:shape="rectangle" >
    <corners android:radius="3dp" />
    <solid android:color="#000000" />
    <stroke
        android:width="2px"
        android:color="#ffffff" />
</shape>
activity_browse_pic.xml 

<GridView xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/grid_view"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent"
    android:numColumns="auto_fit"
    android:gravity="center"
    android:stretchMode="columnWidth"
    android:background="#000000"> 
</GridView>
activity_fullscreenview_pic.xml 

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical" >

    <android.support.v4.view.ViewPager
        android:id="@+id/pager"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent" />

</LinearLayout>
fullscreen_image.xml 

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent" >

    <ImageView
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:scaleType="fitCenter"
        android:id="@+id/imgDisplay"
         />

    <Button
        android:id="@+id/btnClose"
        android:layout_width="wrap_content"
        android:layout_height="30dp"
        android:layout_alignParentRight="true"
        android:layout_alignParentTop="true"
        android:layout_marginRight="15dp"
        android:layout_marginTop="15dp"
        android:background="@drawable/button_background"
        android:paddingBottom="2dp"
        android:paddingTop="2dp"
        android:text="Close"
        android:textColor="#ffffff" />
    
    <Button
        android:id="@+id/btnDelete"
        android:layout_width="wrap_content"
        android:layout_height="30dp"
        android:layout_alignParentLeft="true"
        android:layout_alignParentTop="true"
        android:layout_marginLeft="15dp"
        android:layout_marginTop="15dp"
        android:background="@drawable/button_background"
        android:paddingBottom="2dp"
        android:paddingTop="2dp"
        android:text="Delete"
        android:textColor="#ffffff" />

</RelativeLayout>

添加一个手势缩放

package com.example.view;

import android.content.Context;
import android.graphics.Matrix;
import android.graphics.PointF;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.util.Log;
import android.view.MotionEvent;
import android.view.ScaleGestureDetector;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;

public class TouchImageView 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 TouchImageView(Context context) {
		super(context);
		sharedConstructing(context);
	}

	public TouchImageView(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();
	}
}












lu161513
关注
评论 2
添加红包

请填写红包祝福语或标题

个

红包个数最小为10个

元

红包金额最低5元

当前余额3.43元 前往充值 >
需支付：10.00元
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付元
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明：

1.余额是钱包充值的虚拟货币，按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载，可以购买VIP、付费专栏及课程。

余额充值