我正在尝试使用github simple 示例的okHttp 但是我有这个错误..检查下面的logcat
09-23 09:29:29.566 13750-13750/com.justedhak.www.test E/AndroidRuntime﹕ FATAL EXCEPTION: main
java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.justedhak.www.test/com.justedhak.www.test.MainActivity}: java.lang.ClassCastException: com.justedhak.www.test.MainActivity cannot be cast to android.app.Activity
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1983)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
at android.app.ActivityThread.access$600(ActivityThread.java:130)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4745)
at java.lang.reflect.Method.invokeNative(Native Method)
at java.lang.reflect.Method.invoke(Method.java:511)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:786)
at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:553)
at dalvik.system.NativeStart.main(Native Method)
Caused by: java.lang.ClassCastException: com.justedhak.www.test.MainActivity cannot be cast to android.app.Activity
at android.app.Instrumentation.newActivity(Instrumentation.java:1053)
at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1974)
at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2084)
at android.app.ActivityThread.access$600(ActivityThread.java:130)
at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1195)
at android.os.Handler.dispatchMessage(Handler.java:99)
at android.os.Looper.loop(Looper.java:137)
at android.app.ActivityThread.main(ActivityThread.java:4745)
at java.lang.reflect.Method.invokeNative(Native Method)
这是显而易见的
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.justedhak.www.test" >
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:theme="@style/AppTheme" >
<activity
android:name=".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>
</application>
</manifest>
主要活动
import com.squareup.okhttp.OkHttpClient;
import com.squareup.okhttp.Request;
import com.squareup.okhttp.Response;
import java.io.IOException;
public class MainActivity {
OkHttpClient client = new OkHttpClient();
String run(String url) throws IOException {
Request request = new Request.Builder()
.url(url)
.build();
Response response = client.newCall(request).execute();
return response.body().string();
}
public static void main(String[] args) throws IOException {
MainActivity example = new MainActivity();
String response = example.run("https://raw.github.com/square/okhttp/master/README.md");
System.out.println(response);
}
}
修改
package com.example.justedhak;
import java.io.ByteArrayOutputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.util.ArrayList;
import java.util.Calendar;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.net.Uri;
import android.os.Bundle;
import android.view.View;
import android.widget.ArrayAdapter;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Spinner;
import android.widget.Toast;
public class AddImage extends Activity {
InputStream inputStream;
String categorie;
String caption;
// private Bitmap bmp;
ImageView imageview;
@Override
public void onCreate(Bundle icicle) {
super.onCreate(icicle);
setContentView(R.layout.main);
//get values
EditText captionetxt = (EditText) findViewById(R.id.caption);
caption = captionetxt.getText().toString();
//spinner
Spinner dropdown = (Spinner)findViewById(R.id.spinner1);
String[] items = new String[]{"Lebanese jokes", "Student Jokes", "Quotes"};
ArrayAdapter<String> adapter = new ArrayAdapter<String>(this, android.R.layout.simple_spinner_item, items);
dropdown.setAdapter(adapter);
categorie = dropdown.getSelectedItem().toString();
imageview = (ImageView) findViewById(R.id.imageView);
Intent intent = getIntent();
String selectedImage= intent.getStringExtra("imagePath");
Uri fileUri = Uri.parse(selectedImage);
InputStream imageStream = null;
try {
imageStream = getContentResolver().openInputStream(fileUri);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
Bitmap bmp = BitmapFactory.decodeStream(imageStream);
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bmp.compress(Bitmap.CompressFormat.JPEG, 30, stream);
byte[] byteArray = stream.toByteArray();
Bitmap bitmap = BitmapFactory.decodeByteArray(byteArray, 0, byteArray.length);
imageview.setImageBitmap(bitmap);
}
public void onclick(View view)
{
Toast.makeText(AddImage.this, "Uploading Image", Toast.LENGTH_LONG).show();
upload();
Intent i = new Intent(this,
MainActivity.class);
startActivity(i);
}
public void upload()
{
Calendar thisCal = Calendar.getInstance();
thisCal.getTimeInMillis();
// android.util.Log.i("Time Class ", " Time value in millisecinds "+ thisCal);
// Bitmap bitmap = BitmapFactory.decodeResource(getResources(),R.drawable.ic_launcher);
// ByteArrayOutputStream stream = new ByteArrayOutputStream();
// bmp.compress(Bitmap.CompressFormat.PNG, 90, stream); //compress to which format you want.
// up in oncreate
Intent intent = getIntent();
String selectedImage= intent.getStringExtra("imagePath");
Uri fileUri = Uri.parse(selectedImage);
System.out.println(fileUri);
InputStream imageStream = null;
try {
imageStream = getContentResolver().openInputStream(fileUri);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
Bitmap bmp = BitmapFactory.decodeStream(imageStream);
ByteArrayOutputStream stream = new ByteArrayOutputStream();
bmp.compress(Bitmap.CompressFormat.JPEG, 30, stream);
byte[] byteArray = stream.toByteArray();
Bitmap bitmap = BitmapFactory.decodeByteArray(byteArray, 0, byteArray.length);
imageview.setImageBitmap(bitmap);
int width = bitmap.getWidth();
int height = bitmap.getHeight();
System.out.println(width);
System.out.println(height);
getResizedBitmap( bitmap, 200);
try {
stream.close();
stream = null;
} catch (IOException e) {
e.printStackTrace();
}
String image_str = Base64.encodeBytes(byteArray);
final ArrayList<NameValuePair> nameValuePairs = new ArrayList<NameValuePair>();
nameValuePairs.add(new BasicNameValuePair("image",image_str));
nameValuePairs.add(new BasicNameValuePair("caption",caption));
nameValuePairs.add(new BasicNameValuePair("name","je"));
nameValuePairs.add(new BasicNameValuePair("categorie",categorie));
Thread t = new Thread(new Runnable() {
@Override
public void run() {
try{
HttpClient httpclient = new DefaultHttpClient();
HttpPost httppost = new HttpPost("http://justedhak.comlu.com/images/upload_image.php");
httppost.setEntity(new UrlEncodedFormEntity(nameValuePairs));
HttpResponse response = httpclient.execute(httppost);
final String the_string_response = convertResponseToString(response);
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(AddImage.this, "Response " + the_string_response, Toast.LENGTH_LONG).show();
}
});
}catch(final Exception e){
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(AddImage.this, "ERROR " + e.getMessage(), Toast.LENGTH_LONG).show();
}
});
System.out.println("Error in http connection "+e.toString());
}
}
});
t.start();
}
public String convertResponseToString(HttpResponse response) throws IllegalStateException, IOException{
String res = "";
StringBuffer buffer = new StringBuffer();
inputStream = response.getEntity().getContent();
final int contentLength = (int) response.getEntity().getContentLength(); //getting content length…..
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(AddImage.this, "contentLength : " + contentLength, Toast.LENGTH_LONG).show();
}
});
if (contentLength < 0){
}
else{
byte[] data = new byte[512];
int len = 0;
try
{
while (-1 != (len = inputStream.read(data)) )
{
buffer.append(new String(data, 0, len)); //converting to string and appending to stringbuffer…..
}
}
catch (IOException e)
{
e.printStackTrace();
}
try
{
inputStream.close(); // closing the stream…..
}
catch (IOException e)
{
e.printStackTrace();
}
res = buffer.toString(); // converting stringbuffer to string…..
runOnUiThread(new Runnable() {
@Override
public void run() {
Toast.makeText(AddImage.this, "Result : res", Toast.LENGTH_LONG).show();
}
});
//System.out.println("Response => " + EntityUtils.toString(response.getEntity()));
}
return res;
}
public Bitmap getResizedBitmap(Bitmap image, int maxSize) {
int width = image.getWidth();
int height = image.getHeight();
float bitmapRatio = (float)width / (float) height;
if (bitmapRatio > 0) {
width = maxSize;
height = (int) (width / bitmapRatio);
} else {
height = maxSize;
width = (int) (height * bitmapRatio);
}
return Bitmap.createScaledBitmap(image, width, height, true);
}
}
答案 0 :(得分：1)
link中的GetExample不是活动。
import android.util.Log;
import com.squareup.okhttp.OkHttpClient;
import com.squareup.okhttp.Request;
import com.squareup.okhttp.Response;
import java.io.IOException;
public class MainActivity extends Activity {
private static final String TAG = "MainActivity";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.your_layout);
try {
String response = getResponse("https://raw.github.com/square/okhttp/master/README.md");
Log.d(TAG, response);
} catch (IOException ioe) {
Log.e(TAG, ioe.getMessage());
}
}
private String getResponse(String url) throws IOException {
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder()
.url(url)
.build();
Response response = client.newCall(request).execute();
return response.body().string();
}
}
请确保在顶部和其他所需导入中包含正确的包名称。这是未经测试的代码。
答案 1 :(得分：1)
您需要在AsyncTask中调用以下行：
OkHttpClient client = new OkHttpClient();
Request request = new Request.Builder()
.url(url)
.build();
Response response = client.newCall(request).execute();
return response.body().string();
它对我有用