我是android的新手，我正在使用app。我需要使用滑动从服务列表中下载URL图像。问题是我的项目在列表中包括两个textviews和imageview所以当我发送图像到项目我得到这个错误“android.widget.RelativeLayout不能强制转换为android.widget.ImageView” 我搜索了很多，我找不到合适的解决方案。 这是我在导航抽屉活动中的代码，称为主页
public class mainpage extends AppCompatActivity
implements NavigationView.OnNavigationItemSelectedListener {
ProgressDialog prgDialog;
private ListView lv;
private String TAG = MainActivity.class.getSimpleName();
ArrayList<HashMap<String, String>> contactList = new ArrayList<HashMap<String, String>>();
String[] img = new String[1000];
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_mainpage);
Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
setSupportActionBar(toolbar);
prgDialog = new ProgressDialog(this);
prgDialog.setMessage("Please wait............");
prgDialog.setCancelable(false);
String serverURL = "server url name";
String url = "images url ";
lv = (ListView) findViewById(R.id.updatelist);
ImageView image = (ImageView) findViewById(R.id.image1);
ImageView imagee = (ImageView) findViewById(R.id.image);
//public Context context;
String[] img = new String[1000];
loader im=new loader(mainpage.this,img);
lv.setAdapter(im);
Picasso.with(getApplication()).load("http://i.imgur.com/DvpvklR.png").into(image);
new LoadService().execute(serverURL);
FloatingActionButton fab = (FloatingActionButton) findViewById(R.id.fab);
fab.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
.setAction("Action", null).show();
}
});
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
ActionBarDrawerToggle toggle = new ActionBarDrawerToggle(
this, drawer, toolbar, R.string.navigation_drawer_open, R.string.navigation_drawer_close);
drawer.setDrawerListener(toggle);
toggle.syncState();
NavigationView navigationView = (NavigationView) findViewById(R.id.nav_view);
navigationView.setNavigationItemSelectedListener(this);
}
@Override
public void onBackPressed() {
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
if (drawer.isDrawerOpen(GravityCompat.START)) {
drawer.closeDrawer(GravityCompat.START);
} else {
super.onBackPressed();
}
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.mainpage, 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();
//noinspection SimplifiableIfStatement
if (id == R.id.action_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
@SuppressWarnings("StatementWithEmptyBody")
@Override
public boolean onNavigationItemSelected(MenuItem item) {
// Handle navigation view item clicks here.
int id = item.getItemId();
android.app.FragmentManager fragmentManager = getFragmentManager();
if (id == R.id.project) {
// Handle the camera action
fragmentManager.beginTransaction().replace(R.id.content_frame, new FirstFragment()).commit();
} else if (id == R.id.newproject) {
fragmentManager.beginTransaction().replace(R.id.content_frame, new SecondFragment()).commit();
} else if (id == R.id.joboffers) {
fragmentManager.beginTransaction().replace(R.id.content_frame, new ThirdFragment()).commit();
} else if (id == R.id.employee) {
fragmentManager.beginTransaction().replace(R.id.content_frame, new FourthFragment()).commit();
} else if (id == R.id.nav_share) {
} else if (id == R.id.nav_send) {
}
DrawerLayout drawer = (DrawerLayout) findViewById(R.id.drawer_layout);
drawer.closeDrawer(GravityCompat.START);
return true;
}
private class LoadService extends AsyncTask<String, Void, Void> {
private final HttpClient Client = new DefaultHttpClient();
private String Content;
private String Error = null;
private final String TAG = null;
private ProgressDialog Dialog = new ProgressDialog(mainpage.this);
//TextView uiUpdate = (TextView) findViewById(R.id.text);
//TextView projectname = (TextView) findViewById(R.id.projectname);
//TextView status = (TextView) findViewById(R.id.status);
//TextView descrip = (TextView) findViewById(R.id.description);
ImageView imagee = (ImageView) findViewById(R.id.image);
String url = "images url";
String[] img = new String[1000];
// lv.setAdapter(new ImageLoader(, img));
protected void onPreExecute() {
// uiUpdate.setText("");
//projectname.setText("");
//status.setText("");
//descrip.setText("hello");
Dialog.setMessage("Loading service..");
Dialog.show();
Dialog.dismiss();
//Dialog.setCancelable(false);
// descrip.setText("bye");
}
protected Void doInBackground(String... urls) {
try {
HttpGet httpget = new HttpGet(urls[0]);
ResponseHandler<String> responseHandler = new BasicResponseHandler();
Content = Client.execute(httpget, responseHandler);
} catch (ClientProtocolException e) {
Error = e.getMessage();
cancel(true);
} catch (IOException e) {
Error = e.getMessage();
cancel(true);
}
return null;
}
protected void onPostExecute(Void unused) {
// Close progress dialog
Dialog.dismiss();
Log.e(TAG, "Raw output "
+ Content);
try {
// Load json data and display
JSONObject json = new JSONObject(Content);
//String responseString = json.getString("name");
JSONArray jre = json.getJSONArray("updates");
//HashMap<String, String> project = new HashMap<String, String>();
for (int j = 0; j < jre.length(); j++) {
JSONObject jobject = jre.getJSONObject(j);
String name11 = jobject.getString("title");
String description = jobject.getString("description");
//String statu = jobject.getString("status");
String image = jobject.getString("image");
String total = url + image;
img[j] = total;
HashMap<String, String> contact = new HashMap<>();
// adding each child node to HashMap key => value
contact.put("title", name11);
contact.put("description", description);
contact.put(url+image,total);
//contact.put("status", statu);
contactList.add(contact);
}
} catch (JSONException e) {
e.printStackTrace();
}
// uiUpdate.setText( Content);
ListAdapter adapter = new SimpleAdapter(mainpage.this, contactList, R.layout.item, new String[]{"title", "description"}, new int[]{R.id.title, R.id.description});
//ImageLoader im=new ImageLoader(mainpage.this,img);
lv.setAdapter(adapter);
}
}
public class loader extends ArrayAdapter {
public Context context;
private LayoutInflater inflater;
private String[] img;
public loader(Context context, String[] img) {
super(context, R.layout.item, img);
this.context = context;
this.img = img;
inflater = LayoutInflater.from(context);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// ImageView imgshow = (ImageView) findViewById(R.id.image1);
RecyclerView.ViewHolder holder;
if (null == convertView) {
convertView = inflater.inflate(R.layout.item, parent, false);
}
Glide.with(context)
.load(img[position]) // THE ERROR IS HERE
.into((ImageView) convertView);
return convertView;
}
}
}
这是我的item.xml
<RelativeLayout
xmlns:app="http://schemas.android.com/apk/res-auto"
android:orientation="vertical" android:layout_width="match_parent"
android:layout_height="match_parent"
android:background="@color/gray4">
<TextView
android:text="TextView"
android:layout_width="300dp"
android:layout_height="wrap_content"
android:id="@+id/title"
android:textSize="25dp"
android:layout_weight="0.22" />
<TextView
android:text="TextView"
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/description"
android:textSize="18dp"
android:layout_below="@+id/title"
android:layout_weight="0.54" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:srcCompat="@drawable/back"
android:id="@+id/imageview" />
我的主页
<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:app="http://schemas.android.com/apk/res-auto"
xmlns:tools="http://schemas.android.com/tools"
android:id="@+id/content_mainpage"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="0dp"
android:paddingLeft="0dp"
android:paddingRight="0dp"
android:paddingTop="0dp"
app:layout_behavior="@string/appbar_scrolling_view_behavior"
tools:context="commyc.example.blu_ray91111.timslinesoluation.mainpage"
tools:showIn="@layout/app_bar_mainpage">
<FrameLayout
android:layout_width="match_parent"
android:layout_height="match_parent"
android:id="@+id/content_frame"
android:layout_centerHorizontal="true"
android:layout_alignParentTop="true">
<TextView
android:text="our news "
android:layout_width="wrap_content"
android:layout_height="wrap_content"
android:id="@+id/textView19"
android:textSize="24sp"
android:textColor="@color/colorAccent" />
<ImageView
android:layout_width="wrap_content"
android:layout_height="wrap_content"
app:srcCompat="@mipmap/back5"
android:id="@+id/image1" />
<ListView
android:layout_width="wrap_content"
android:id="@+id/updatelist"
android:layout_height="400dp"
android:layout_marginTop="63dp"
android:layout_alignParentTop="true"
android:layout_alignParentStart="true" />
</FrameLayout>
</RelativeLayout>
答案 0 :(得分：0)
这是一个解决方案：
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// ImageView imgshow = (ImageView) findViewById(R.id.image1);
RecyclerView.ViewHolder holder;
if (null == convertView) {
convertView = inflater.inflate(R.layout.item, parent, false);
}
ImageView imageView = (ImageView) convertView.findViewById(R.id.imageview)
Glide.with(context)
.load(img[position]) // THE ERROR IS HERE
.into(imageView);
return convertView;
}
答案 1 :(得分：0)
以下是您无法在getView方法
中访问imageview的解决方案访问imageview在你的getView（）
中试试ImageView imgshow = (ImageView) convertView.findViewById(R.id.image1);
convertiview是布局的参考，然后你可以在使用之后访问imageview。希望这会有所帮助。:)
答案 2 :(得分：0)
public class loader extends ArrayAdapter {
public Context context;
private LayoutInflater inflater;
private String[] img;
public loader(Context context, String[] img) {
super(context, R.layout.item, img);
this.context = context;
this.img = img;
inflater = LayoutInflater.from(context);
}
@Override
public View getView(int position, View convertView, ViewGroup parent) {
// ImageView imgshow = (ImageView) findViewById(R.id.image1);
RecyclerView.ViewHolder holder;
ImageView imgshow;
if (null == convertView) {
convertView = inflater.inflate(R.layout.item, parent, false);
imgshow = (ImageView) convertView.findViewById(R.id.image1);
}
Glide.with(context)
.load("http://phone.tmsline.com/images/upload/"+img[position]) // THE ERROR IS HERE
.into(imgshow);
Log.e("image_url,"http://phone.tmsline.com/images/upload/"+img[position]);
return convertView;
}
Try this code....
答案 3 :(得分：0)
问题是通过在适配器中执行以下操作：
Glide.with(context)
.load(img[position]) // THE ERROR IS HERE
.into((ImageView) convertView);
您正在尝试在布局item.xml的根视图中加载图像，并且该布局的根是RelativeLayout，因此错误“android.widget.RelativeLayout无法转换为android.widget.ImageView”
您应该通过
检索子图像ViewImageView imageView = (ImageView) convertView.findViewById(R.id.imageview)
然后你可以这样做：
Glide.with(context)
.load(img[position]) // THE ERROR IS HERE
.into(imageView);