ios 调用writeToFile将图片保存到本地一直失败的解决方案

Posted 2023-05-06

参考技术A 该问题纠结了我半天时间。。。查了很多资料，最后才发现调用writeToFile返回false的原因。在此附上解决方案：

NSData *imageData = UIImageJPEGRepresentation(currentImage, 1.0f);//currentImage是传过来的UIImage

NSString *inewImageName=[self getImagePath:imageName];//imageName为图片名称

BOOL operation = [imageData writeToFile:newImageName options:NSAtomicWrite error:&error];

方法：

- (NSString*)getImagePath:(NSString *)name

 NSArray *path = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);

 NSString *docPath = [path objectAtIndex:0];

 NSFileManager *fileManager = [NSFileManager defaultManager];

 NSString *finalPath = [docPath stringByAppendingPathComponent:name];

 // Remove the filename and create the remaining path

[fileManager createDirectoryAtPath:[finalPath stringByDeletingLastPathComponent] withIntermediateDirectories:YES attributes:nil error:nil];//stringByDeletingLastPathComponent是关键

 return finalPath;



希望能帮助大家解决问题哈~

Android下载图片/调用系统相机拍照显示并保存到本地

package com.example.testhttpget;

import java.io.BufferedReader;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.InputStreamReader;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.HttpClient;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.DefaultHttpClient;

import android.app.Activity;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Bundle;
import android.os.Environment;
import android.os.Handler;
import android.os.Message;
import android.provider.MediaStore;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.ImageView;
import android.widget.TextView;


public class MainActivity extends Activity {

	ImageView iamgeview = null;
	
	Handler myHandler = new Handler() {  
        public void handleMessage(Message msg) {   
             switch (msg.what) {   
                  case 1:   
                	  iamgeview.setImageBitmap((Bitmap)msg.obj);
                       break;   
             }   
             super.handleMessage(msg);   
        }   
   };  
	
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        
        final TextView hello = (TextView)findViewById(R.id.hello);
        iamgeview = (ImageView)findViewById(R.id.imageview);
        
        // 子线程网络下载图片
        new Thread(){
        	public void run(){
        		String imgurl = "http://photocdn.sohu.com/20111123/Img326603573.jpg";
        		HttpGet mHttpGet = new HttpGet(imgurl);
        		
//        		 HttpGet mHttpGet = new HttpGet("http://image.baidu.com/search/detail?ct=503316480&z=0&ipn=d&word=%E7%86%8A%E7%8" +
//        		 		"C%AB&step_word=&hs=0&pn=0&spn=0&di=28270682580&pi=&rn=1&tn=baiduimagedetail&is=0%2C0&istype=0&ie=utf-8&oe=utf-8&in=&cl=2&lm=-1&st=undefined&cs=404637145%2C3982267385&os=3438506744%2C3869227355&simid=0%2C0&adpicid=0&ln=1975&fr=&fmq=1475036112689_R&fm=&ic=undefined&s=undefined&se=&sme=&tab=0&width=&height=&face=undefined&ist=&jit=&cg=&bdtype=11&oriquery=&objurl=http%3A%2F%2Fpic4.40017.cn%2Fscenery%2Fdestination%2F2016%2F07%2F17%2F16%2FNylDjq.jpg" );
        		 HttpClient mHtppClient = new DefaultHttpClient();
        		 try{
        			 // 发送get请求并获得相应对象
        			HttpResponse httpRespose = mHtppClient.execute(mHttpGet);
        			// 取得消息实体
        			HttpEntity entrie = httpRespose.getEntity();
        			 // 从消息实体取得输入流
        			InputStream inputstream = entrie.getContent();
        			// 将输入流转化成BufferedReader
        			BufferedReader bufferReader = new BufferedReader(
        					new InputStreamReader(inputstream));
        			String result = "";
        			String line = "";
        			
//        			for(;(line = bufferReader.readLine())!=null;){
//        				result += line ;
//        			}
//        			hello.setText(result);
        			
        			Bitmap bitmap = BitmapFactory.decodeStream(inputstream);  
        			
        			saveImg2SDcard(bitmap,"/WebTakePhone.jpg");
        			
        			Message msg = new Message(); 
        			msg.obj = bitmap;
        			msg.what = 1;
        			myHandler.sendMessage(msg);
        		 }catch(Exception e){
//        			 hello.setText("请求错误"+e.toString());
        		 };
        	}
        }.start();
        
        // 调用系统相机拍照并保存图片、展示图片
        findViewById(R.id.takephotos).setOnClickListener(new OnClickListener() {
			
			@Override
			public void onClick(View v) {
				// 调用系统相机
				Intent intent = new Intent(MediaStore.ACTION_IMAGE_CAPTURE);
		        startActivityForResult(intent,1);
			}
		});
    }

    @Override
   	protected void onActivityResult(int requestCode, int resultCode, Intent data) {
   		super.onActivityResult(requestCode, resultCode, data);
   		if(resultCode == Activity.RESULT_OK){
   			Bundle bundle = (Bundle)data.getExtras();
   			Bitmap bitmap = (Bitmap)bundle.get("data");
   			
   			saveImg2SDcard(bitmap,"/systemTakePhone.jpg");
   		}
   	}
    
    private void saveImg2SDcard(Bitmap bitmap,String fileName) {
    	FileOutputStream fos;
			try {
				if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) { 
					fos = new FileOutputStream(Environment.getExternalStorageDirectory().getAbsoluteFile()+fileName);
				}else{
					fos = new FileOutputStream(getFilesDir()+fileName);
				}
				bitmap.compress(Bitmap.CompressFormat.JPEG, 100, fos);
				iamgeview.setImageBitmap(bitmap);
			} catch (FileNotFoundException e) {
				e.printStackTrace();
			}
	}

	@Override
    public boolean onCreateOptionsMenu(Menu menu) {
        // Inflate the menu; this adds items to the action bar if it is present.
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
}