Here is simple solution:
The new data on the server: https://dl.dropboxusercontent.com/u/31298901/demo/demo_image.txt
The AndroidManifest.xml file
<uses-permission android:name="android.permission.INTERNET" />
<application
android:allowBackup="true"
android:icon="@mipmap/ic_launcher"
android:label="@string/app_name"
android:supportsRtl="true"
android:theme="@style/AppTheme">
<activity android:name=".MainActivity">
<intent-filter>
<action android:name="android.intent.action.MAIN" />
<category android:name="android.intent.category.LAUNCHER" />
</intent-filter>
</activity>
</application>
MainActivity class
public class MainActivity extends AppCompatActivity {
GridView gridView;
MyGridAdapter myGridAdapter;
private static String DATA_URL = "https://dl.dropboxusercontent.com/u/31298901/demo/demo_image.txt";
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
gridView = (GridView) findViewById(R.id.gridview);
getData();
}
private void getData(){
RequestQueue queue = Volley.newRequestQueue(this);
StringRequest stringRequest = new StringRequest(Request.Method.GET, DATA_URL, new Response.Listener<String>() {
@Override
public void onResponse(String response) {
try {
JSONObject jsonObject = new JSONObject(response);
JSONArray allImageArray = jsonObject.optJSONArray("images");
if(allImageArray != null && allImageArray.length() > 0){
ArrayList<ImageObject> imageObjects = new ArrayList<>();
for(int i = 0; i < allImageArray.length();i++){
JSONObject jsonItem = allImageArray.optJSONObject(i);
imageObjects.add(new ImageObject(jsonItem));
}
myGridAdapter= new MyGridAdapter(MainActivity.this, imageObjects);
runOnUiThread(new Runnable() {
@Override
public void run() {
gridView.setAdapter(myGridAdapter);
}
});
}
} catch (Exception e){
}
}
}, new Response.ErrorListener() {
@Override
public void onErrorResponse(VolleyError error) {
}
});
stringRequest.setRetryPolicy(new DefaultRetryPolicy(6000, DefaultRetryPolicy.DEFAULT_MAX_RETRIES, DefaultRetryPolicy.DEFAULT_BACKOFF_MULT));
queue.add(stringRequest);
}
}
The layout for MainActivity activity_layout.xml
<?xml version="1.0" encoding="utf-8"?>
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.android.vad.gridview.MainActivity">
<GridView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/gridview"
android:columnWidth="120dp"
android:verticalSpacing="10dp"
android:numColumns="auto_fit">
</GridView>
</RelativeLayout>
GridAdapter.java
public class MyGridAdapter extends BaseAdapter{
private Context context;
private ArrayList<ImageObject> imageObjects;
private LayoutInflater mLayoutInflate;
public MyGridAdapter (Context context, ArrayList<ImageObject> imageObjects){
this.context = context;
this.imageObjects = imageObjects;
this.mLayoutInflate = LayoutInflater.from(context);
}
public int getCount() {
if(imageObjects != null) return imageObjects.size();
return 0;
}
@Override
public Object getItem(int position) {
if(imageObjects != null && imageObjects.size() > position) return imageObjects.get(position);
return null;
}
@Override
public long getItemId(int position) {
if(imageObjects != null && imageObjects.size() > position) return imageObjects.get(position).getId();
return 0;
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder viewHolder = null;
if (convertView == null) {
viewHolder = new ViewHolder();
convertView = mLayoutInflate.inflate(R.layout.imageitem, parent,
false);
viewHolder.imageView = (ImageView) convertView.findViewById(R.id.image);
convertView.setTag(viewHolder);
} else {
viewHolder = (ViewHolder) convertView.getTag();
}
ImageObject imageObject = (ImageObject) getItem(position);
if(imageObject != null) {
Glide
.with(context)
.load(imageObject.getImageUrl())
.centerCrop()
.crossFade()
.into(viewHolder.imageView);
}
return convertView;
}
private class ViewHolder {
public ImageView imageView;
}
}
imageitem.xml
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
android:orientation="vertical" android:layout_width="80dp"
android:layout_height="120dp">
<ImageView
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/image"/>
</LinearLayout>
ImageObject.java
public class ImageObject {
private int id;
private String imageUrl;
public ImageObject(){
}
public ImageObject(JSONObject jsonObject){
if(jsonObject == null) return;
this.id = jsonObject.optInt("id");
this.imageUrl = jsonObject.optString("imageUrl");
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getImageUrl() {
return imageUrl;
}
public void setImageUrl(String imageUrl) {
this.imageUrl = imageUrl;
}
}
Dependencies in gradle build
dependencies {
compile fileTree(dir: 'libs', include: ['*.jar'])
testCompile 'junit:junit:4.12'
compile 'com.android.support:appcompat-v7:23.4.0'
compile 'com.github.bumptech.glide:glide:3.7.0'
compile 'com.mcxiaoke.volley:library:1.0.19'
}
