android图片裁剪功能实现详解

一：主布局界面



二：点击控件触发事件后效果图



三：拍照完之后效果图



四：裁剪界面效果图



五：点击相册后返回的图片效果图



六：裁剪完从相册PICK的保存后的效果图



下面直接来看下主控制类代码，如下：

package com.example.photocapture;

//下面来看下裁剪中用到的类，大家详细看下头注释：
/**
* 下面这些注释是下载这个类的时候本来就有的，本来要删除的，但看了下竟然是license，吼吼，
* 好东西，留在注释里，以备不时之用，大家有需要加license的可以到下面的网址找哦
*/

//EPL, Eclipse Public License, V1.0 or later, http://www.eclipse.org/legal //LGPL, GNU Lesser General Public License, V2.1 or later, http://www.gnu.org/licenses/lgpl.html //GPL, GNU General Public License, V2 or later, http://www.gnu.org/licenses/gpl.html //AL, Apache License, V2.0 or later, http://www.apache.org/licenses //BSD, BSD License, http://www.opensource.org/licenses/bsd-license.php /**
* A Base64 encoder/decoder.
*
* <p>
* This class is used to encode and decode data in Base64 format as described in RFC 1521.
*
* <p>
* Project home page: <a href="http://www.source-code.biz/base64coder/java/">www.source-code.biz/base64coder/java</a><br>
* Author: Christian d'Heureuse, Inventec Informatik AG, Zurich, Switzerland<br>
* Multi-licensed: EPL / LGPL / GPL / AL / BSD.
*/

/**
* 这个类在上面注释的网址中有，大家可以自行下载下，也可以直接用这个， 公开的Base64Coder类（不用深究它是怎么实现的，
* 还是那句话，有轮子直接用轮子），好用的要死人了... 小马也很无耻的引用了这个网址下的东东，吼吼...
*
* @Title: Base64Coder.java
* @Package com.xiaoma.piccut.demo
* @Description: TODO
* @author XiaoMa
*/

public class Base64Coder {

// The line separator string of the operating system.
private static final String systemLineSeparator = System
.getProperty("line.separator");

// Mapping table from 6-bit nibbles to Base64 characters.
private static char[] map1 = new char[64];
static {
int i = 0;
for (char c = 'A'; c <= 'Z'; c++)
map1[i++] = c;
for (char c = 'a'; c <= 'z'; c++)
map1[i++] = c;
for (char c = '0'; c <= '9'; c++)
map1[i++] = c;
map1[i++] = '+';
map1[i++] = '/';
}

// Mapping table from Base64 characters to 6-bit nibbles.
private static byte[] map2 = new byte[128];
static {
for (int i = 0; i < map2.length; i++)
map2[i] = -1;
for (int i = 0; i < 64; i++)
map2[map1[i]] = (byte) i;
}

/**
* Encodes a string into Base64 format. No blanks or line breaks are
* inserted.
*
* @param s
*            A String to be encoded.
* @return A String containing the Base64 encoded data.
*/
public static String encodeString(String s) {
return new String(encode(s.getBytes()));
}

/**
* Encodes a byte array into Base 64 format and breaks the output into lines
* of 76 characters. This method is compatible with
* <code>sun.misc.BASE64Encoder.encodeBuffer(byte[])</code>.
*
* @param in
*            An array containing the data bytes to be encoded.
* @return A String containing the Base64 encoded data, broken into lines.
*/
public static String encodeLines(byte[] in) {
return encodeLines(in, 0, in.length, 76, systemLineSeparator);
}

/**
* Encodes a byte array into Base 64 format and breaks the output into
* lines.
*
* @param in
*            An array containing the data bytes to be encoded.
* @param iOff
*            Offset of the first byte in <code>in</code> to be processed.
* @param iLen
*            Number of bytes to be processed in <code>in</code>, starting
*            at <code>iOff</code>.
* @param lineLen
*            Line length for the output data. Should be a multiple of 4.
* @param lineSeparator
*            The line separator to be used to separate the output lines.
* @return A String containing the Base64 encoded data, broken into lines.
*/
public static String encodeLines(byte[] in, int iOff, int iLen,
int lineLen, String lineSeparator) {
int blockLen = (lineLen * 3) / 4;
if (blockLen <= 0)
throw new IllegalArgumentException();
int lines = (iLen + blockLen - 1) / blockLen;
int bufLen = ((iLen + 2) / 3) * 4 + lines * lineSeparator.length();
StringBuilder buf = new StringBuilder(bufLen);
int ip = 0;
while (ip < iLen) {
int l = Math.min(iLen - ip, blockLen);
buf.append(encode(in, iOff + ip, l));
buf.append(lineSeparator);
ip += l;
}
return buf.toString();
}

/**
* Encodes a byte array into Base64 format. No blanks or line breaks are
* inserted in the output.
*
* @param in
*            An array containing the data bytes to be encoded.
* @return A character array containing the Base64 encoded data.
*/
public static char[] encode(byte[] in) {
return encode(in, 0, in.length);
}

/**
* Encodes a byte array into Base64 format. No blanks or line breaks are
* inserted in the output.
*
* @param in
*            An array containing the data bytes to be encoded.
* @param iLen
*            Number of bytes to process in <code>in</code>.
* @return A character array containing the Base64 encoded data.
*/
public static char[] encode(byte[] in, int iLen) {
return encode(in, 0, iLen);
}

/**
* Encodes a byte array into Base64 format. No blanks or line breaks are
* inserted in the output.
*
* @param in
*            An array containing the data bytes to be encoded.
* @param iOff
*            Offset of the first byte in <code>in</code> to be processed.
* @param iLen
*            Number of bytes to process in <code>in</code>, starting at
*            <code>iOff</code>.
* @return A character array containing the Base64 encoded data.
*/
public static char[] encode(byte[] in, int iOff, int iLen) {
int oDataLen = (iLen * 4 + 2) / 3; // output length without padding
int oLen = ((iLen + 2) / 3) * 4; // output length including padding
char[] out = new char[oLen];
int ip = iOff;
int iEnd = iOff + iLen;
int op = 0;
while (ip < iEnd) {
int i0 = in[ip++] & 0xff;
int i1 = ip < iEnd ? in[ip++] & 0xff : 0;
int i2 = ip < iEnd ? in[ip++] & 0xff : 0;
int o0 = i0 >>> 2;
int o1 = ((i0 & 3) << 4) | (i1 >>> 4);
int o2 = ((i1 & 0xf) << 2) | (i2 >>> 6);
int o3 = i2 & 0x3F;
out[op++] = map1[o0];
out[op++] = map1[o1];
out[op] = op < oDataLen ? map1[o2] : '=';
op++;
out[op] = op < oDataLen ? map1[o3] : '=';
op++;
}
return out;
}

/**
* Decodes a string from Base64 format. No blanks or line breaks are allowed
* within the Base64 encoded input data.
*
* @param s
*            A Base64 String to be decoded.
* @return A String containing the decoded data.
* @throws IllegalArgumentException
*             If the input is not valid Base64 encoded data.
*/
public static String decodeString(String s) {
return new String(decode(s));
}

/**
* Decodes a byte array from Base64 format and ignores line separators, tabs
* and blanks. CR, LF, Tab and Space characters are ignored in the input
* data. This method is compatible with
* <code>sun.misc.BASE64Decoder.decodeBuffer(String)</code>.
*
* @param s
*            A Base64 String to be decoded.
* @return An array containing the decoded data bytes.
* @throws IllegalArgumentException
*             If the input is not valid Base64 encoded data.
*/
public static byte[] decodeLines(String s) {
char[] buf = new char[s.length() + 3];
int p = 0;
for (int ip = 0; ip < s.length(); ip++) {
char c = s.charAt(ip);
if (c != ' ' && c != '\r' && c != '\n' && c != '\t')
buf[p++] = c;
}
while ((p % 4) != 0)
buf[p++] = '0';

return decode(buf, 0, p);
}

/**
* Decodes a byte array from Base64 format. No blanks or line breaks are
* allowed within the Base64 encoded input data.
*
* @param s
*            A Base64 String to be decoded.
* @return An array containing the decoded data bytes.
* @throws IllegalArgumentException
*             If the input is not valid Base64 encoded data.
*/
public static byte[] decode(String s) {
return decode(s.toCharArray());
}

/**
* Decodes a byte array from Base64 format. No blanks or line breaks are
* allowed within the Base64 encoded input data.
*
* @param in
*            A character array containing the Base64 encoded data.
* @return An array containing the decoded data bytes.
* @throws IllegalArgumentException
*             If the input is not valid Base64 encoded data.
*/
public static byte[] decode(char[] in) {
return decode(in, 0, in.length);
}

/**
* Decodes a byte array from Base64 format. No blanks or line breaks are
* allowed within the Base64 encoded input data.
*
* @param in
*            A character array containing the Base64 encoded data.
* @param iOff
*            Offset of the first character in <code>in</code> to be
*            processed.
* @param iLen
*            Number of characters to process in <code>in</code>, starting
*            at <code>iOff</code>.
* @return An array containing the decoded data bytes.
* @throws IllegalArgumentException
*             If the input is not valid Base64 encoded data.
*/
public static byte[] decode(char[] in, int iOff, int iLen) {
if (iLen % 4 != 0)
throw new IllegalArgumentException(
"Length of Base64 encoded input string is not a multiple of 4.");
while (iLen > 0 && in[iOff + iLen - 1] == '=')
iLen--;
int oLen = (iLen * 3) / 4;
byte[] out = new byte[oLen];
int ip = iOff;
int iEnd = iOff + iLen;
int op = 0;
while (ip < iEnd) {
int i0 = in[ip++];
int i1 = in[ip++];
int i2 = ip < iEnd ? in[ip++] : 'A';
int i3 = ip < iEnd ? in[ip++] : 'A';
if (i0 > 127 || i1 > 127 || i2 > 127 || i3 > 127)
throw new IllegalArgumentException(
"Illegal character in Base64 encoded data.");
int b0 = map2[i0];
int b1 = map2[i1];
int b2 = map2[i2];
int b3 = map2[i3];
if (b0 < 0 || b1 < 0 || b2 < 0 || b3 < 0)
throw new IllegalArgumentException(
"Illegal character in Base64 encoded data.");
int o0 = (b0 << 2) | (b1 >>> 4);
int o1 = ((b1 & 0xf) << 4) | (b2 >>> 2);
int o2 = ((b2 & 3) << 6) | b3;
out[op++] = (byte) o0;
if (op < oLen)
out[op++] = (byte) o1;
if (op < oLen)
out[op++] = (byte) o2;
}
return out;
}

// Dummy constructor.
private Base64Coder() {
}

} // end class Base64Coder

package com.example.photocapture;

import java.io.File;
import android.app.Activity;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.net.Uri;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.ImageButton;
import android.widget.ImageView;
/**
* @Title: PicCutDemoActivity.java
* @Package com.xiaoma.piccut.demo
* @Description: 图片裁剪功能测试
* @author XiaoMa
*/
public class MainActivity extends Activity implements OnClickListener {

private ImageButton ib = null;
private ImageView iv = null;
private Button btn = null;
private String tp = null;

/** Called when the activity is first created. */
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//初始化
init();
}

/**
* 初始化方法实现
*/
private void init() {
ib = (ImageButton) findViewById(R.id.imageButton1);
iv = (ImageView) findViewById(R.id.imageView1);
btn = (Button) findViewById(R.id.button1);
ib.setOnClickListener(this);
iv.setOnClickListener(this);
btn.setOnClickListener(this);
}

/**
* 控件点击事件实现
*
* 因为有朋友问不同控件的背景图裁剪怎么实现，
* 我就在这个地方用了三个控件，只为了自己记录学习
* 大家觉得没用的可以跳过啦
*/
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.imageButton1:
ShowPickDialog();
break;
case R.id.imageView1:
ShowPickDialog();
break;
case R.id.button1:
ShowPickDialog();
break;

default:
break;
}
}

/**
* 选择提示对话框
*/
private void ShowPickDialog() {
new AlertDialog.Builder(this)
.setTitle("设置头像...")
.setNegativeButton("相册", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.dismiss();
/**
* 刚开始，我自己也不知道ACTION_PICK是干嘛的，后来直接看Intent源码，
* 可以发现里面很多东西，Intent是个很强大的东西，大家一定仔细阅读下
*/
Intent intent = new Intent(Intent.ACTION_PICK, null);

/**
* 下面这句话，与其它方式写是一样的效果，如果：
* intent.setData(MediaStore.Images.Media.EXTERNAL_CONTENT_URI);
* intent.setType(""image/*");设置数据类型
* 如果朋友们要限制上传到服务器的图片类型时可以直接写如："image/jpeg 、 image/png等的类型"
* 这个地方小马有个疑问，希望高手解答下：就是这个数据URI与类型为什么要分两种形式来写呀？有什么区别？
*/
intent.setDataAndType(
MediaStore.Images.Media.EXTERNAL_CONTENT_URI,
"image/*");
startActivityForResult(intent, 1);

}
})
.setPositiveButton("拍照", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int whichButton) {
dialog.dismiss();
/**
* 下面这句还是老样子，调用快速拍照功能，至于为什么叫快速拍照，大家可以参考如下官方
* 文档，you_sdk_path/docs/guide/topics/media/camera.html
* 我刚看的时候因为太长就认真看，其实是错的，这个里面有用的太多了，所以大家不要认为
* 官方文档太长了就不看了，其实是错的，这个地方小马也错了，必须改正
*/
Intent intent = new Intent(
MediaStore.ACTION_IMAGE_CAPTURE);
//下面这句指定调用相机拍照后的照片存储的路径
intent.putExtra(MediaStore.EXTRA_OUTPUT, Uri
.fromFile(new File(Environment
.getExternalStorageDirectory(),
"xiaoma.jpg")));
startActivityForResult(intent, 2);
}
}).show();
}

@Override
protected void onActivityResult(int requestCode, int resultCode, Intent data) {
switch (requestCode) {
// 如果是直接从相册获取
case 1:
startPhotoZoom(data.getData());
break;
// 如果是调用相机拍照时
case 2:
File temp = new File(Environment.getExternalStorageDirectory()
+ "/xiaoma.jpg");
startPhotoZoom(Uri.fromFile(temp));
break;
// 取得裁剪后的图片
case 3:
/**
* 非空判断大家一定要验证，如果不验证的话，
* 在剪裁之后如果发现不满意，要重新裁剪，丢弃
* 当前功能时，会报NullException，小马只
* 在这个地方加下，大家可以根据不同情况在合适的
* 地方做判断处理类似情况
*
*/
if(data != null){
setPicToView(data);
}
break;
default:
break;

}
super.onActivityResult(requestCode, resultCode, data);
}

/**
* 裁剪图片方法实现
* @param uri
*/
public void startPhotoZoom(Uri uri) {
/*
* 至于下面这个Intent的ACTION是怎么知道的，大家可以看下自己路径下的如下网页
* yourself_sdk_path/docs/reference/android/content/Intent.html
* 直接在里面Ctrl+F搜：CROP ，之前小马没仔细看过，其实安卓系统早已经有自带图片裁剪功能,
* 是直接调本地库的，小马不懂C C++  这个不做详细了解去了，有轮子就用轮子，不再研究轮子是怎么
* 制做的了...吼吼
*/
Intent intent = new Intent("com.android.camera.action.CROP");
intent.setDataAndType(uri, "image/*");
//下面这个crop=true是设置在开启的Intent中设置显示的VIEW可裁剪
intent.putExtra("crop", "true");
// aspectX aspectY 是宽高的比例
intent.putExtra("aspectX", 1);
intent.putExtra("aspectY", 1);
// outputX outputY 是裁剪图片宽高
intent.putExtra("outputX", 150);
intent.putExtra("outputY", 150);
intent.putExtra("return-data", true);
startActivityForResult(intent, 3);
}

/**
* 保存裁剪之后的图片数据
* @param picdata
*/
private void setPicToView(Intent picdata) {
Bundle extras = picdata.getExtras();
if (extras != null) {
Bitmap photo = extras.getParcelable("data");
Drawable drawable = new BitmapDrawable(photo);

/**
* 下面注释的方法是将裁剪之后的图片以Base64Coder的字符方式上
* 传到服务器，QQ头像上传采用的方法跟这个类似
*/

/*ByteArrayOutputStream stream = new ByteArrayOutputStream();
photo.compress(Bitmap.CompressFormat.JPEG, 60, stream);
byte[] b = stream.toByteArray();
// 将图片流以字符串形式存储下来

tp = new String(Base64Coder.encodeLines(b));
这个地方大家可以写下给服务器上传图片的实现，直接把tp直接上传就可以了，
服务器处理的方法是服务器那边的事了，吼吼

如果下载到的服务器的数据还是以Base64Coder的形式的话，可以用以下方式转换
为我们可以用的图片类型就OK啦...吼吼
Bitmap dBitmap = BitmapFactory.decodeFile(tp);
Drawable drawable = new BitmapDrawable(dBitmap);
*/
ib.setBackgroundDrawable(drawable);
iv.setBackgroundDrawable(drawable);
}
}

}

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context=".MainActivity" >

<TextView
android:id="@+id/textView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:text="@string/hello_world" />

<Button
android:id="@+id/button1"
style="?android:attr/buttonStyleSmall"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignLeft="@+id/textView1"
android:layout_alignParentBottom="true"
android:layout_marginBottom="42dp"
android:text="Button" />

<ImageView
android:id="@+id/imageView1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_below="@+id/textView1"
android:layout_centerHorizontal="true"
android:layout_marginTop="68dp"
android:src="@drawable/ic_launcher" />

<ImageButton
android:id="@+id/imageButton1"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:layout_alignTop="@+id/button1"
android:layout_toRightOf="@+id/imageView1"
android:src="@drawable/ic_launcher" />

</RelativeLayout>

Base64算法大家可以参考我转载的另一篇文章，其作用有详细解释。