图片浏览器

一：Mainactivity的配置

importAndroid.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Handler;
import android.os.Message;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.text.TextUtils;
import android.view.View;
import android.widget.EditText;
import android.widget.ImageView;
import android.widget.Toast;

import Java.io.InputStream;
import java.NET.HttpURLConnection;
import java.net.URI;
import java.Net.URL;


public class MainActivity extends AppCompatActivity {
    protected static final intCHANGE_UI=1;
    protected static final intERROR=2;
    private EditText et_path;
    private ImageView iv;
    private Handler handler=newHandler(){
        public voidhandleMessage(android.os.Message msg){
            if(msg.what==CHANGE_UI){
                Bitmap bitmap=(Bitmap) msg.obj;
                iv.setImageBitmap(bitmap);
            }
            else if(msg.what==ERROR){
                Toast.makeText(MainActivity.this,"显示图片错误",0).show();
            }
        };
    };


    @Override
    protected voidonCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        et_path=(EditText) findViewById(R.id.et_path);
        iv=(ImageView) findViewById(R.id.iv);
    }
    public voidclick(View view){
        finalString path=et_path.getText().toString().trim();
        if (TextUtils.isEmpty(path)){
            Toast.makeText(this,"图片路径不能为空",0).show();
        }else{
            newThread() {
                privateHttpURLConnectionconn;
                privateBitmap bitmap;

                public voidrun() {
                    try{
                        URL url =new URL(path);
                        conn= (HttpURLConnection) url.openConnection();
                        conn.setRequestMethod("GET");
                        conn.setConnectTimeout(5000);
                        conn.setRequestProperty("User-Agent","Mozilla/4.0(compatible;MSIE 6.0;Windows NT 5.1;"+ "SV1;.NET4.OC;.NET4.OE;NET CLR 2.0.502727;"+ ".NET CLR 3.0.4506.2152;.NET  CLR 3.5.30729;Shuame)");
                        intcode = conn.getResponseCode();
                        if(code == 200) {
                            InputStream is =conn.getInputStream();
                            bitmap= BitmapFactory.decodeStream(is);
                            Message msg =new Message();
                            msg.what= CHANGE_UI;
                            msg.obj= bitmap;
                            handler.sendMessage(msg);

                        }else {
                            Message msg =new Message();
                            msg.what= ERROR;
                            handler.sendMessage(msg);
                        }


                    }catch (Exception e) {
                        e.printStackTrace();
                        Message msg =new Message();
                        msg.what= ERROR;
                        handler.sendMessage(msg);
                    }
                };
            }.start();
        }
            }
        }

二：activity_main.xml的配置

第三步：AndroidMinafest.xml的配置