增加了图片放大缩小功能,一共用到三个类。MainActivity仅作为添加fragment用,其全部代码如:
package com.example.ex_1213_mypic;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
import android.view.Menu;
public class MainActivity extends FragmentActivity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
addFragment();//添加片段
}
private void addFragment() {
FragmentManager fm = getSupportFragmentManager();
FragmentTransaction ft = fm.beginTransaction();
MyFragment myFragment = new MyFragment();
ft.add(R.id.fl_replace, myFragment);
ft.commit();
}
@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;
}
}
mainActivity添加完fragment就放寒假了。
先在fragment的xml里添加两张默认图片:
得到所需图片地址,并通过AsyncTask执行下载,将下载完的图片放进声明出来的bitmapList中,全部下载完成后再初始化控件:
package com.example.ex_1213_mypic;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.ArrayList;
import android.content.Intent;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.ImageView;
public class MyFragment extends Fragment implements OnClickListener{
String [] urlList = {
"http://7qn7nu.com1.z0.glb.clouddn.com/77.jpg",
"http://7qn7nu.com1.z0.glb.clouddn.com/u=3516622004,3632540994&fm=59.jpg"
};
private View layout;
ArrayList<Bitmap> bitmapList = new ArrayList<Bitmap>();
public MyFragment() {
// Required empty public constructor
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
if(layout == null){
layout = getActivity().getLayoutInflater().inflate(R.layout.fragment_my, null);
initBitmap();//下载图片
}else{
ViewGroup parent = (ViewGroup) layout.getParent();
parent.removeView(layout);
}
return layout;
}
private int index;
private void initBitmap() {
MyAsync myAsync = new MyAsync();
if(index < 2){
//下载图片
myAsync.execute(urlList[index]);
}else{
initView();//初始化控件
}
}
AsyncTask下载过程:
class MyAsync extends AsyncTask<String, Void, Bitmap>{
@Override
protected Bitmap doInBackground(String... params) {
URL url;
Bitmap bitmap = null;
try {
url = new URL(params[0]);
//URLConnection con=url.openConnection();
HttpURLConnection con=(HttpURLConnection) url.openConnection();
con.setDoInput(true);
con.connect();
InputStream is=con.getInputStream();
bitmap=BitmapFactory.decodeStream(is);
is.close();
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return bitmap;
}
@Override
protected void onPostExecute(Bitmap bitmap) {
// TODO Auto-generated method stub
super.onPostExecute(bitmap);
if (bitmap != null) {
if(index < 2){
bitmapList.add(bitmap);
index++;
initBitmap();
}
}
}
}
将下载完成的bitmap显示到控件中:
private void initView() {
ImageView img1 = (ImageView) layout.findViewById(R.id.imageView1);
ImageView img2 = (ImageView) layout.findViewById(R.id.imageView2);
img1.setImageBitmap(bitmapList.get(0));
img2.setImageBitmap(bitmapList.get(1));
img1.setOnClickListener(this);
img2.setOnClickListener(this);
}
这样就可以将网络上的图片正常显示到APP里了,记得添加权限:
<uses-permission android:name="android.permission.INTERNET"/>
最后fragment的图片传到MyTouchActivity里。首先在MyTouchActivity写一个方法用来接收图片:
public void getBitmapInfo(Bitmap bitmap, int position){
this.bitmap = bitmap;
this.position = position;
}
执行图片的点击事件时,先new 出MyTouchActivity对象并调用上面所写方法传入图片:
//传出对应的图片到MytouchActivity,同时从当前activity跳转到MytouchActivity
private void initClickBitmap(int x) {
Intent intent = new Intent();
MyTouchActivity touchActivity = new MyTouchActivity();
if(bitmapList.size() > x){
touchActivity.getBitmapInfo(bitmapList.get(x), x);
intent.setClass(getActivity(), MyTouchActivity.class);
startActivity(intent);
}
}
@Override
public void onClick(View v) {
switch (v.getId()) {
case R.id.imageView1:
initClickBitmap(0);
break;
case R.id.imageView2:
initClickBitmap(1);
break;
default:
break;
}
}
在MyTouch里将接收到的bitmap显示出来就可以了。
简单写一个例子,供有需要的朋友参考,新手上路,不足之处请大侠们海涵并多指教哈~