相关疑难解决方法(0)

我想将图像从URL保存到SD卡(以备将来使用),然后从SD卡加载该图像,将其用作Google地图的可绘制叠加层.

这是函数的保存部分:

//SAVE TO FILE

String filepath = Environment.getExternalStorageDirectory().getAbsolutePath(); 
String extraPath = "/Map-"+RowNumber+"-"+ColNumber+".png";
filepath += extraPath;

FileOutputStream fos = null;
fos = new FileOutputStream(filepath); 

bmImg.compress(CompressFormat.PNG, 75, fos);

//LOAD IMAGE FROM FILE
Drawable d = Drawable.createFromPath(filepath);
return d;

图像以succuessfully的形式保存到SD卡,但在到达createFromPath()线路时失败.我不明白为什么它会保存到那个目的地但不加载它....

我在点击按钮时从URL加载图像,并将其存储为位图.现在我想知道如何将下载的图像保存到SD卡以及系统中.

我试图通过以下方式实现:

package com.v3.thread.fetchImage;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import android.app.Activity;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.os.Environment;
import android.provider.MediaStore;
import android.util.Log;
import android.view.View;
import android.widget.Button;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;

public class MainThreadActivity extends Activity {
    ImageView imView;
    EditText ed1;
    Bitmap bmImg;
    Button bt, btSave;
    String imageUrl = "";
    int visibilty = 0;

    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle icicle) { …

我要救的ImageView,我与展示setImageURI在SDcard我的Android设备中...

我怎样才能做到这一点？

码:

public class MainActivity extends ActionBarActivity {

ImageView imageView;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    imageView = (ImageView) findViewById(R.id.imageView);

    imageView.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            Intent intent = new Intent();
            intent.setType("image/*");
            intent.setAction(Intent.ACTION_GET_CONTENT);
            startActivityForResult(Intent.createChooser(intent, "Select Image"), 1);
        }
    });
}

@Override
protected void onActivityResult(int reqCode, int resCode, Intent data) {
    if(resCode == RESULT_OK){
        if(reqCode == 1)
            imageView.setImageURI(data.getData());
    }
}

提前致谢.