Java 创建图像文件,android
我想上传一个图像到我的亚马逊s3服务器。 为此,我需要为我要发送的图像创建一个文件,但不知何故它无法工作: 按钮以选择图像:Java 创建图像文件,android,java,android,image,file-upload,Java,Android,Image,File Upload,我想上传一个图像到我的亚马逊s3服务器。 为此,我需要为我要发送的图像创建一个文件,但不知何故它无法工作: 按钮以选择图像: //When clicked on addimage addImage.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { // To open up a
//When clicked on addimage
addImage.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View v) {
// To open up a gallery browser
Intent intent = new Intent();
intent.setType("image/*");
intent.setAction(Intent.ACTION_GET_CONTENT);
startActivityForResult(Intent.createChooser(intent, "Select Picture"), PICK_IMAGE);
}
单击库中的图像时:
@Override
public void onActivityResult(int requestCode, int resultCode, Intent data) {
super.onActivityResult(requestCode, resultCode, data);
if (requestCode == PICK_IMAGE && resultCode == Activity.RESULT_OK && null != data) {
urimg = data.getData();
String path = getPath(urimg);
//create file of image to upload
images3 = new File(path);
}
}
});
getPath方法:
public String getPath(Uri uri) {
if( uri == null ) {
return null;
}
String[] projection = { MediaStore.Images.Media.DATA };
Cursor cursor = getActivity().getContentResolver().query(uri, projection, null, null, null);
if( cursor != null ){
int column_index = cursor
.getColumnIndexOrThrow(MediaStore.Images.Media.DATA);
cursor.moveToFirst();
return cursor.getString(column_index);
}
return uri.getPath();
}
我得到这个错误:
12-05 01:37:13.857 30611-30611/com.laurenswuyts.witpa E/AndroidRuntime﹕ FATAL EXCEPTION: main
Process: com.laurenswuyts.witpa, PID: 30611
java.lang.RuntimeException: Failure delivering result ResultInfo{who=null, request=65537, result=-1, data=Intent { dat=content://com.android.providers.media.documents/document/image:3000 flg=0x1 }} to activity {com.laurenswuyts.witpa/com.laurenswuyts.witpa.Activities.Events.AddEventActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'char[] java.lang.String.toCharArray()' on a null object reference
at android.app.ActivityThread.deliverResults(ActivityThread.java:3539)
at android.app.ActivityThread.handleSendResult(ActivityThread.java:3582)
at android.app.ActivityThread.access$1300(ActivityThread.java:144)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1327)
at android.os.Handler.dispatchMessage(Handler.java:102)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5221)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'char[] java.lang.String.toCharArray()' on a null object reference
at java.io.File.fixSlashes(File.java:185)
at java.io.File.<init>(File.java:134)
12-05 01:37:13.857 30611-30611/com.laureswuyts.witpa E/AndroidRuntime﹕ 致命异常:主
流程:com.laureswuyts.witpa,PID:30611
java.lang.RuntimeException:未能传递结果ResultInfo{who=null,request=65537,result=-1,data=Intent{dat=content://com.android.providers.media.documents/document/image:3000 flg=0x1}}到活动{com.laureswuyts.witpa/com.laureswuyts.witpa.Activities.Events.AddEventActivity}:java.lang.NullPointerException:尝试对空对象引用调用虚拟方法“char[]java.lang.String.ToCharray()”
位于android.app.ActivityThread.deliverResults(ActivityThread.java:3539)
位于android.app.ActivityThread.handleSendResult(ActivityThread.java:3582)
在android.app.ActivityThread.access$1300(ActivityThread.java:144)
在android.app.ActivityThread$H.handleMessage(ActivityThread.java:1327)
位于android.os.Handler.dispatchMessage(Handler.java:102)
位于android.os.Looper.loop(Looper.java:135)
位于android.app.ActivityThread.main(ActivityThread.java:5221)
位于java.lang.reflect.Method.invoke(本机方法)
位于java.lang.reflect.Method.invoke(Method.java:372)
在com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)上
位于com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
原因:java.lang.NullPointerException:尝试对空对象引用调用虚拟方法“char[]java.lang.String.toCharArray()”
位于java.io.File.fixSlashes(File.java:185)
在java.io.File.(File.java:134)
要保存图像时,请使用此类保存图像
import java.io.FileOutputStream;
import java.text.SimpleDateFormat;
import java.util.Date;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;
import android.graphics.Canvas;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;
import android.os.Environment;
import android.util.Log;
public class SaveImageIntoDrawable {
public static String savedImagePath = "" ;
public static Bitmap drawableToBitmap (Drawable drawable) {
if (drawable instanceof BitmapDrawable) {
return ((BitmapDrawable)drawable).getBitmap();
}
Bitmap bitmap = Bitmap.createBitmap(drawable.getIntrinsicWidth(), drawable.getIntrinsicHeight(), Config.ARGB_8888);
Canvas canvas = new Canvas(bitmap);
drawable.setBounds(0, 0, canvas.getWidth(), canvas.getHeight());
drawable.draw(canvas);
return bitmap;
}
public static void saveBitmapIntoDrawable(Bitmap bitmap, Context object) {
try {
String timeStamp = new SimpleDateFormat("ddMMyyyy_HHmm").format(new Date());
savedImagePath = Environment.getExternalStorageDirectory() + "/imagename"+timeStamp+".png" ;
FileOutputStream out = new FileOutputStream(savedImagePath);
Log.i(object.getFilesDir().getAbsolutePath(), "complete-path");
bitmap.compress(Bitmap.CompressFormat.PNG, 90, out);
out.close();
} catch (Exception err) {
err.printStackTrace();
Log.i("Error in SaveImageIntoDrawable ", "Error");
}
}
}
并使用此类发布您的图像:
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Dictionary;
import java.util.Enumeration;
import java.util.List;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.entity.BufferedHttpEntity;
import org.apache.http.entity.mime.HttpMultipartMode;
import org.apache.http.entity.mime.MultipartEntity;
import org.apache.http.entity.mime.content.FileBody;
import org.apache.http.entity.mime.content.StringBody;
import org.apache.http.impl.client.DefaultHttpClient;
import org.json.JSONObject;
import android.app.ProgressDialog;
import android.content.Context;
import android.os.AsyncTask;
import android.util.Log;
import com.secondhandbooks.util.ConvertStreamIntoString;
import com.secondhandbooks.util.SaveImageIntoDrawable;
public abstract class BaseAsync_Post extends AsyncTask<String, String, InputStream>
{
Context context ;
private HttpPost httppost;
String url ;
Dictionary<String, String> dictionary ;
public BaseAsync_Post(String url , Dictionary<String, String> dictionary, Context context) {
this.url = url ;
this.dictionary = dictionary;
this.context = context ;
Enumeration<String> enumeration = dictionary.keys() ;
showLogs("constructor") ;
while ( enumeration.hasMoreElements() )
{
showLogs( enumeration.nextElement() ) ;
}
}
@Override
abstract protected void onPreExecute() ;
@Override
abstract protected void onPostExecute(InputStream result) ;
@Override
protected InputStream doInBackground(String... params) {
// TODO Auto-generated method stub
// TODO Auto-generated method stub
InputStream is = null;
HttpClient httpclient = new DefaultHttpClient();
httppost = new HttpPost(url);
MultipartEntity entity = new MultipartEntity(HttpMultipartMode.BROWSER_COMPATIBLE);
try
{
List<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>(50);
Enumeration<String> enumeration = dictionary.keys() ;
while ( enumeration.hasMoreElements() )
{
String key = enumeration.nextElement() ;
if ( key.equals("file") )
{
final File file = new File(SaveImageIntoDrawable.savedImagePath);
if ( file.isFile() )
{
showLogs("is file");
}
else
{
showLogs("no-file");
}
FileBody fb = new FileBody(file);
entity.addPart(key, fb);
}
else
{
entity.addPart(key, new StringBody(dictionary.get(key)));
}
}
httppost.setEntity(entity);
HttpResponse response = httpclient.execute(httppost);
HttpEntity entity1 = response.getEntity();
BufferedHttpEntity bufHttpEntity = new BufferedHttpEntity(entity1);
is = bufHttpEntity.getContent();
} catch (ClientProtocolException e) {
e.printStackTrace();
showLogs("ClientProtocolException");
} catch (IOException e) {
e.printStackTrace();
showLogs("IOException");
}
return is;
}
public String getString(JSONObject json, String TAG) {
String returnParseData = "";
try {
Object aObj = json.get(TAG);
if (aObj instanceof Boolean) {
returnParseData = Boolean.toString(json.getBoolean(TAG));
} else if (aObj instanceof Integer) {
returnParseData = Integer.toString(json.getInt(TAG));
} else if (aObj instanceof String) {
returnParseData = json.getString(TAG);
} else {
returnParseData = json.getString(TAG);
}
} catch (Exception err) {
err.printStackTrace();
returnParseData = "";
}
return returnParseData;
}
public String getIntintoString(JSONObject json, String TAG) {
int returnParseData = -1;
try {
returnParseData = json.getInt(TAG) ;
} catch (Exception err) {
err.printStackTrace();
returnParseData = -1;
}
return Integer.toString(returnParseData) ;
}
public void showLogs ( String msg )
{
Log.e("HTTP-POST", msg) ;
}
}
导入java.io.File;
导入java.io.IOException;
导入java.io.InputStream;
导入java.util.ArrayList;
导入java.util.Dictionary;
导入java.util.Enumeration;
导入java.util.List;
导入org.apache.http.HttpEntity;
导入org.apache.http.HttpResponse;
导入org.apache.http.NameValuePair;
导入org.apache.http.client.ClientProtocolException;
导入org.apache.http.client.HttpClient;
导入org.apache.http.client.methods.HttpPost;
导入org.apache.http.entity.BufferedHttpEntity;
导入org.apache.http.entity.mime.HttpMultipartMode;
导入org.apache.http.entity.mime.MultipartEntity;
导入org.apache.http.entity.mime.content.FileBody;
导入org.apache.http.entity.mime.content.StringBody;
导入org.apache.http.impl.client.DefaultHttpClient;
导入org.json.JSONObject;
导入android.app.ProgressDialog;
导入android.content.Context;
导入android.os.AsyncTask;
导入android.util.Log;
导入com.secondhandbooks.util.ConvertStreamIntoString;
导入com.secondhandbooks.util.SaveImageIntoDrawable;
公共抽象类BaseAsync\u Post扩展了AsyncTask
{
语境;
私有HttpPost HttpPost;
字符串url;
字典;
public BaseAsync_Post(字符串url、字典字典、上下文){
this.url=url;
这本字典=字典;
this.context=上下文;
枚举=dictionary.keys();
展示日志(“建造商”);
while(枚举.hasMoreElements())
{
showLogs(enumeration.nextElement());
}
}
@凌驾
抽象受保护的void onPreExecute();
@凌驾
抽象受保护的void onPostExecute(InputStream结果);
@凌驾
受保护的InputStream doInBackground(字符串…参数){
//TODO自动生成的方法存根
//TODO自动生成的方法存根
InputStream=null;
HttpClient HttpClient=新的DefaultHttpClient();
httppost=新的httppost(url);
MultipartEntity=新的MultipartEntity(HttpMultipartMode.BROWSER_兼容);
尝试
{
List nameValuePairs=新的ArrayList(50);
枚举=dictionary.keys();
while(枚举.hasMoreElements())
{
String key=enumeration.nextElement();
if(key.equals(“文件”))
{
最终文件=新文件(SaveImageIntoDrawable.savedImagePath);
if(file.isFile())
{
显示日志(“is文件”);
}
其他的
{
显示日志(“无文件”);
}
FileBody fb=新的FileBody(文件);
实体。添加部分(键,fb);
}
其他的
{
addPart(key,newstringbody(dictionary.get(key));
}
}
httppost.setEntity(实体);
HttpResponse response=httpclient.execute(httppost);
HttpEntity entity1=response.getEntity();
BufferedHttpEntity bufHttpEntity=新的BufferedHttpEntity(entity1);
is=bufhttpenty.getContent();
}捕获(客户端协议例外e){
e、 printStackTrace();
显示日志(“客户端协议例外”);
}捕获(IOE异常){
e、 printStackTrace();
显示日志(“IOException”);
}
回报是;
}
公共字符串getString(JSONObject json,字符串标记){
字符串returnParseData=“”;
试一试{
对象aObj=json.get(标记);
if(aObj instanceof Boolean){
returnParseData=Boolean.toString(json.getBoolean(TAG));
}else if(aObj instanceof Integer){